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RADI

LARIA

VOLUME 20

SEPTEMBER 2002

NEWSLETTER OF THE INTERNATIONAL ASSOCIATION OF RADIOLARIAN PALEONTOLOGISTS ISSN: 0297.5270

INTERRAD International Association of Radiolarian Paleontologists A Research Group of the International Paleontological Association

Officers of the Association President

Past President

PETER BAUMBARTNER

JOYCE R. BLUEFORD

Lausanne, Switzerland [email protected]

[email protected]

California, USA

Secretary

Treasurer

JONATHAN AITCHISON

ELSPETH URQUHART

Department of Earth Sciences University of Hong Kong Pokfulam Road, Hong Kong SAR, CHINA Tel: (852) 2859 8047 Fax: (852) 2517 6912 e-mail: [email protected]

JOIDES Office Department of Geology and Geophysics University of Miami - RSMAS 4600 Rickenbacker Causeway Miami FL 33149 Florida U.S.A. Tel: 1-305-361-4668 Fax: 1-305-361-4632 Email: [email protected]

Working Group Chairmen Paleozoic

Cenozoic

PATRICIA, WHALEN, U.S.A.

ANNIKA SANFILIPPO California, U.S.A.

[email protected]

[email protected]

Mesozoic

Recent

RIE S. HORI Matsuyama, JAPAN

DEMETRIO BOLTOVSKOY Buenos Aires, ARGENTINA

[email protected]

[email protected]

I N T E R R A D is an international non-profit organization for researchers interested in all aspects of radiolarian taxonomy, palaeobiology, morphology, biostratigraphy, biology, ecology and paleoecology. INTERRAD is a Research Group of the International Paleontological Association (IPA). Since 1978 members of INTERRAD meet every three years to present papers and exchange ideas and materials INTERRAD M EMBERSHIP: The international Association of Radiolarian Paleontologists is open to any one interested on receipt of subscription. The actual fee US $ 15 per year. Membership queries and subscription send to Treasurer. Changes of address can be sent to the Secretary. B IBLIOGRAPHIES: The bibliographies are produced by the Secretary. Any suggestion, reprints of articles and details of omission should be sent to him directly. Please send reprints of any radiolarian article to the Secretary this facilitate the edition of forthcoming bibliographies.

RADIOLARIA Newsletter of the International Association of Radiolarian Paleontologists ISSN: 0297-5270

VOLUME 20

SEPTEMBER 2002

Editor: Jonathan Aitchison

CONTENTS

EDITORS NOTE .....................................................................................................................................2 THE PLIENSBACHIAN TO AALENIAN WORKING GROUP T/J BOUNDARY WORKING GROUP PALEOZOIC WORKING GROUP

S. Gorican and E.S. Carter.....3 E. S. Carter and Rie S. Hori.....4 Patricia Whalen.....5

LATE CRETACEOUS – EARLY PALEOGENE WORKING GROUP – UPDATE Chris Hollis.....6 RADIOLARIAN BIBLIOGRAPHY 2001-2002

Jonathan Aitchison.....7

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EDITORS NOTE

Another year has passed since the last issue of RADIOLARIA. Doubtless many of you are looking forward to our next meeting being organized by Peter and colleagues in Laussanne. I hope to see you all there.

Without your contributions many would lose touch of what is happening in the rad world. Unless I get around to producing another issue before the meeting next year this will be my last time as secretary of Interrad and editor of this newsletter. I wish my successor my joy in continuing this tradition.

Thanks to all of you who contributed copies or details of publications, working group reports and other material to this rather slim issue.

Regards

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Jonathan Aitchison

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THE PLIENSBACHIAN TO AALENIAN WORKING GROUP Spela Gorican and Elizabeth Carter

The Pliensbachian – Aalenian Working Group was formed in 2000 and the first meeting was held in July 2001 in Ljubljana with six members in attendance: Beth Carter, Paulian Dumitrica, Spela Gorican, Rie Hori, Luis O’Dogherty and Patricia Whalen. The purpose of the group is to produce a catalogue and a zonation (similar to that of Baumgartner et al. 1995) for the Pliensbachian, Toarcian and Aalenian. Zonation of these stages is essential to span the missing interval between the well established Hettangian to Sinemurian (Carter et al. 1998) and Middle Jurassic to Lower Cretaceous (Baumgartner et al. 1995) radiolarian biozones.

The systematics of 280 taxa has been agreed upon thus far and will be included in the catalogue. Each taxon will be presented with an up-to-date synonymy, original and subsequent definitions, remarks, and data on geographic distribution. Plates will illustrate the holotype and sufficient other specimens from different paleogeographic realms to clearly illustrate intraspecific variability. The biochronological scale will integrate radiolarian-occurrence data from measured sections in the Circum-Pacific belt (Baja California, Oregon, British Columbia, Japan) and the Tethyan realm (Oman, Turkey, Slovenia, Austria). Jean Guex will be involved in calculating the range chart (protoreferential) using the BioGraph computer program which is based on the Unitary Association Method (UA). Calibration for this new zonation will be based on ammonites co-occurring with radiolarians in Queen Charlotte Islands (British Columbia). The first draft of the zonation will be presented at the 6th ISJS meeting in Palermo; the final version is planned for end 2003.

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T/J BOUNDARY WORKING GROUP Elizabeth S. Carter and Rie S. Hori Studies of the Triassic/Jurassic boundary at Kennecott Point and Kunga Island in Queen Charlotte Islands continue. Fieldwork in the summer of 2000 focused on finely detailed sampling of the isotope and radiolarian successions across the boundary interval at both localities. Closely spaced ash beds right around the boundary were collected for age dating and a system of permanent markers was put in place at Kunga Island. A paper discussing the relationship between the observed negative isotope anomaly and the end-Triassic radiolarian extinction was published in a recent issue of Science (Ward et al. 2001) (see bibliography this publication for reference and abstract). In other news, IGCP 458 - Triassic-Jurassic Boundary Events, was established in 2001 with funding scheduled for 2001-2005. The leaders of this project are Jozsef Pálfy (Hungary), Steven Hesselbo (UK) and Chris McRoberts (USA). Several Interrad members (Beth Carter, Jean Guex, Rie Hori, Keisuke Ishida, Atsushi Matsuoka, and Kagan Tekin) are currently involved in this project. If any others are interested, please contact Jozsef Pálfy ([email protected]). At the first Workshop of Project 458 in Taunton, England, October 2001, our Queen Charlotte Islands group (Haggart et al. - see bibliography this issue) presented a poster reporting multidisciplinary results. An abstract on the radiolarian fauna was submitted also. Updated results on T-J boundary sections in Queen Charlotte Islands will be presented at the 6th.Jurassic Symposium in Palermo, Sicily this coming September 2002. News of T/J boundary study from Japan: Rie Hori is reexamining radiolarian biostratigraphy at the T/J boundary in the Inuyama area for detail comparison with recent radiolarian data from Queen Charlotte provided by Beth Carter and, together with a student, is studying geochemical analysis in the boundary layers. Preliminary results suggest an influence of impact ejecta existing in the T/J boundary strata. A. Matsuoka, and N. Suzuki are also summarizing radiolarian data at the T/J boundary from Philippine and Japan as co-working project. These results will be discussed at the workshop, Okinawa Is., November 2002. We would be pleased if other workers concerned with radiolarians around the T-J boundary would please send news of their activities to either E.S. Carter of R.S. Hori for inclusion in the next Working Group Report in RADIOLARIA.

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PALEOZOIC WORKING GROUP Dear Paleozoic Colleagues, We look forward to hearing about your research activities and recent publications. If you would take the time to complete the following questionnaire, the editor can include it in the next version of this newsletter. Please send contributions via email. Thank you. Patricia Whalen EMAIL OR FAX: Email: [email protected] FAX: 501-253-2031 MAIL: Dr. Patricia Whalen, Department of Geosciences, University of Arkansas, Fayetteville, 118 Ozark Hall, Fayetteville, AR 72701, U.S.A 1. NAME: 2. ADDRESS: 3. PHONE: 4. FAX: 5. EMAIL: 6. OCCUPATION: For the next three questions, 7-9, it would be very helpful if you wrote a short paragraph describing the highlights of your research and field work - what you are really excited about. Also important are the projects that you are supervising with your graduate students and post-docs. Don't let this form cramp your style - just let us know what you have been doing! 7. CURRENT RESEARCH INTERESTS/PROJECTS, INCLUDING THE WORK OF YOUR GRADUATE STUDENTS AND POST-DOCS: 8. NEWS AND ANNOUNCEMENTS: 9. FIELD WORK, TRAVEL AND CONFERENCES: 10: RECENT PUBLICATIONS:

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LATE CRETACEOUS – EARLY PALEOGENE WORKING GROUP - UPDATE Members Yoshiaki Aita, Marta Bak, Peter Baumgartner, Kjell Bjørklund, Chuck Blome, Taniel Danelian, Paulian Dumitrica, Valesca Portilla Eilert, John Gregory, Chris Hollis, Donna Hull, Liu Jianbing, Kiyoshi Kawabata, Irina Khokhlova, Hsin Yi Ling, Marta Marcucci, Atsushi Matsuoka, Cathy Nigrini, Akiko Nishimura, Irina Popova, Mensi Rela, Toyasaburo Sakai, Annika Sanfilippo, Tatiana Shikova, Torstein Steiger, Osamu Takahashi, Elspeth Urquhart, Valentina Vishnevskaya. Co-chairs Hollis and Sanfilippo Aim of working group: The aim of this working group is to co-ordinate research effort in Late Cretaceous-Eocene radiolarians in order to (1) better understand radiolarian evolution through the CretaceousCenozoic transition and (2) to improve the utility of radiolarians as guides to environmental changes across the K/T and P/E boundaries. The first step towards achieving this aim is the integration of regional biozonations, which requires consistency in the identification of key species. To assist in the consistent application of species concepts, we intend to establish a web-based taxonomic database of regional key species. The primary focus is latest Cretaceous (Campanian) to early Eocene, but we encourage all researchers studying Late Cretaceous and Paleogene radiolarians to contribute to the database. Progress: There has been limited progress on the items identified for action at INTERRAD 2000, i.e. initiation of a taxonomic database; translation of Kozlova monograph, and development of an IGCP proposal. The working group agreed to establish a taxonomic database via two web sites: Jane Dolven’s “Radiolaria.org” (www.radiolaria.org) and Radworld (Nigrini, Caulet & Sanfilippo: http://www.mnhn.fr/mnhn/geo/radworld/radworldsite/radsearch.html). Jane’s website is useful for downloading preliminary data, including photographs from regional collections, which may require discussion and modification. Radworld is useful for collating original descriptions and illustrations. Both web sites are now up and running and working group members are encouraged to contribute. Jean-Pierre Caulet has found time to translate parts of the Kozlova monograph into English, notably descriptions of plagiacanthid and archipilid taxa and the Paleogene biozonation. Chris Hollis has been following up various ideas for IGCP proposal but has not yet investigated the potential for a project on “radiolarians as indicators of past productivity changes” with an emphasis on episodes of major global changes in the Late Cretaceous and early Cenozoic. IGCP support is still seen as a good way to promote the working group – but may need to be discussed again in 2003. Current research activities Dumitrica: Late Cretaceous of Oman, Romania and Italy Eilert: Late Cretaceous, Brazil Hollis: Paleocene of ODP Site 1121 (Leg 181); Paleocene-Eocene transition in Clarence Valley, Marlborough, New Zealand; review of global biosiliceous sedimentation patterns through the PaleoceneEocene transition as part of NSF BIOPE program. Sanfilippo: Eocene of ODP Leg 199

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Bibliography - 2001-2002

B IBLIOGRAPHY 2001-2002 Jonathan Aitchison

This compilation contains 130 references, mostly covering the 2001-2002 period. This list of publications has been possible thanks to the collaboration of colleagues who have sent their articles and I am grateful to all who have done this.

AFANASIEVA, M. S. 2002. A New Classification of Paleozoic Radiolaria. Paleontological Journal 36 (2), 14-29.

paleoceanographic history. In: ( M A T S U O K A , A. eds). Paleoceanography of the Panthalassa-Tethys Invitation t o Global Field Science Topics in Paleontology 2 . 1-16. Paleontological Society of Japan.

A new classification of Paleozoic Radiolaria is developed. The subphylum Radiolaria includes two classes, i.e., Pheodaria and Polycystina. The class Polycystina is composed of the following seven orders: Sphaerellaria Haeckel, 1881, Stauraxonaria Afanasieva, 2000, Aculearia Afanasieva, 1999, Albaillellaria Deflandre, 1953, emend. Afanasieva, 1999, Pylomaria Afanasieva, 1999, Nassellaria* Ehrenberg, 1847, and Collodaria* Haeckel, 1881 (* unknown in the Paleozoic). The diagnoses of 87 radiolarian taxa are given, among them five orders, 18 superfamilies, 28 families, and 36 subfamilies.

ANDO, A., KODAMA, K. & KOJIMA, S. 2001. Low-latitude and Southern Hemisphere origin of Anisian (Triassic) bedded chert in the Inuyama area, Mino Terrane, central Japan. Journal of Geophysical Research, B, Solid Earth and Planets 106 (2), 1973-1986. B A K , K., B A K , M. & PA U L , Z. 2001. Barnasiowka radiolarian shale formation; a new lithostratigraphic unit i n the upper Cenomanian-lowermost Turonian of the Polish Outer Carpathians (Silesian Series). Annales Societatis Geologorum Poloniae 71 (2), 75-103.

A F A N A S I E V A , M. S. & MI K H A I L O V A , M. V. 2001. The Domanik Formation of the Timan–Pechora Basin: Radiolarians, Biostratigraphy, and Sedimentation Conditions. Stratigraphy and Geological Correlation 9 (5), 419-440.

B AKHTEEV, M. K., PALECHEK, T. N., TIKHOMIROVA, S. R. & M OROZOV, O. A. 2002. Campanian Radiolarians from the Northern Part of the Valaginskii Ridge (Eastern Kamchatka). Stratigraphy and Geological Correlation 1 0 (4), 365-374.

A diverse radiolarian assemblage of 127 species was studied for the first time from the middle Frasnian Domanik Formation of the Timan–Pechora province. The availability of sponge spicules, acritarchs, and rhizomorphs is proved. After a detailed analysis of macerated radiolarians, three subassemblages (lower Rdm-1, middle Rdm-2, upper Rdm-3) of substantially different quantitative and qualitative composition were distinguished in the Moskovistella allbororum–Ceratoikiscum ukhtensis radiolarian assemblage. Echinate species of Aculearia prevail over spherical Sphaerellaria forms, and this suggests a relatively cold conditions in bottom water mass. Cyclically changing taphocoenoses testify to significant ecological rearrangements during the Domanik time. A new interpretation of depositional conditions for Domanik Formation sediments in the southern Timan–Pechora basin of Russia i s presented.

The allochthonous northwestern and central tectonic sheets of the Valaginskii Group have been studied in the eastern Kamchatka. Cherty rocks of the Poputnaya and Golubaya sequences yield here abundant radiolarians. The results of radiolarian analysis imply that both sequences accumulated concurrently in the late Campanian time. Data on taxonomic composition, morphology, and abundance rates of radiolarian taxa from the Valaginskii Ridge suggest that some of their assemblages populated an ecotone between the highlatitude and temperate zones:The allochthonous northwestern and central tectonic sheets of the Valaginskii Group have been studied in the eastern Kamchatka. Cherty rocks of the Poputnaya and Golubaya sequences yield here abundant radiolarians. The results of radiolarian analysis imply that both sequences accumulated concurrently in the late Campanian time. Data on taxonomic composition, morphology, and abundance rates of radiolarian taxa from the Valaginskii Ridge suggest that some of their assemblages populated an ecotone between the high-latitude and temperate zones.

AIELLO, I. W. & HAGSTRUM, J. T. 2001. Paleomagnetism and paleogeography of Jurassic radiolarian cherts from the Northern Apennines of Italy. Geological Society o f America Bulletin 113 (4), 469-481. Oriented samples of Jurassic radiolarian chert were collected from the Tuscan domain (continental margin) and the Ligurid domain (oceanic) of the northern Apennines for paleomagnetic study to determine the paleogeographic origins of these rocks. The oceanic rocks are all thermochemically overprinted by a mostly reversedpolarity component of magnetization (B) that was likely acquired during late Miocene regional uplift of the northern Apennines. This component also dominates the lower brittle chert of the Tuscan Cherts, but disappears upsection in the more clay-rich and ductile siliceous maristones. In addition, the Tuscan Cherts retain an inferred primary magnetization (C), isolated at temperatures between 560 and 660 °C, which passes a fold test and shows a polarity stratigraphy. This component indicates a paleolatitude of 11° ± 4°N, and a counterclockwise vertical-axis rotation of 29° ± 9° with respect to the southern Alps of Italy, of 49° ± 8° with respect to Africa, and of 91° ± 8° with respect to Eurasia. Our results suggest that the Tuscan domain was farther south than other deepwater continental margin sections of Adria, and that transcurrent faulting might have played a significant role in the orogenic evolution of the northern Apennines.

BARTOLINI, A. & LARSON, R. L. 2001. Pacific Microplate and the Pangea supercontinent in the Early to Middle Jurassic. Geology (Boulder) 29 (8), 735-738. New biostratigraphic data based on radiolarians recovered from deep within the oceanic crustal section of Ocean Drilling Program Hole 801C in the western Pacific, along with existing radiometric information, date this oceanic crust as late Bajocian-early Bathonian (170-165 Ma). The overlying basal sediments at Hole 801C are essentially identical in age (middle Bathonian, 164-162 Ma) to the basal sediments at Deep Sea Drilling Program Hole 534A in the central Atlantic. We estimate the time of formation of the Pacific plate as 175-170 Ma and the time of initial separation of the Pangea supercontinent in the central Atlantic as 190-180 Ma. We also identify a time of extensive subduction-zone magmatism (175159 Ma) at the eastern and western edges of Pangea. We suggest that the initial plate separation of Pangea increased subduction rates at its outer margins and altered the plate boundaries in the Pacific superocean, leading to formation of the Pacific plate.

AITA, Y., SAKAI, T., TAKEMURA, A., et al. 2001. Unlocking the radiolarian record from the Mesozoic terranes of New Zealand: Investigating the southern high latitude 7

Bibliography - 2001-2002

Radiolaria 20 deviations occur only for events "b1 " and "g". Furthermore, the long-term fluctuations in C. davisiana abundances have been studied in a sediment core covering the last 700 kyr. Based on biostratigraphic extinction levels, ages for early Brunhes C. davisiana events have been estimated. Major C. davisiana abundance maxima occur approximately every 100 ka in conjunction with glacial/interglacial cycles over the entire record.

B ILL, M., O, D. L., GUEX, J., et al. 2001. Radiolarite ages i n Alpine-Mediterranean ophiolites; constraints on the oceanic spreading and the Tethys-Atlantic connection. Geological Society of America Bulletin 113 (1), 129-143. The history of continental breakup and oceanic spreading of the Alpine Tethys is defined by a revision of isotopic and biochronologic ages of 65 stratigraphic sections located in the Alps, Apennines, Betic Cordillera, Rif, and central Atlantic and a reinterpretation of the stratigraphic sequences of surpraophiolitic radiolarites. The biochronology of radiolarites is revised by using the deterministic approach known as the unitary association method. During the early Bajocian (unitary association zone, UAZ 3) radiolarite sedimentation began at the continental margin. Biochronologic ages determined in the lowermost radiolarites in basinal sequences of Tethyan margins are synchronous and mark a regional change in sedimentation regime in the Alpine Tethys. The onset of oceanic spreading of the Alpine Tethys is dated by isotopic methods as Bajocian, and i s consistent with the timing of the structural evolution of the continental margins. The earliest fragments of Tethyan oceanic crust are characterized by the associations of ophiolites with deepsea sediments, and coarse reworked sediments including platform and continental basement fragments. The earliest ophiolites also show geochemical affinities with synrift and transitional midoceanic-ridge basalts. The oldest radiolarites on oceanic crust are so far dated as Bathonian (UAZ 6) and are located in the Gets nappe (western Alps), in the Balagne nappe (Corsica), and in the central Atlantic (Deep Sea Drilling Project [DSDP]; Site 534A). The oldest remnants of Alpine Tethyan crust have been identified in weakly metamorphosed cover nappes that occupy an external tectonic position in the Alpine orogenic belts, as compared to the main ophiolitic sutures. Thus, the older relics of oceanic lithosphere were the first to be accreted and transported onto the foreland during the collision. Siliceous sedimentation during the early Bajocian i s correlated with westward deep-water circulation in the Alpine Tethys related to the opening of deep seaways between Laurasia and Gondwana. In the central Atlantic no radiolarites, but thin radiolarian-rich layers, were deposited during the earliest Bathonian (UAZ 6). The similarity between radiolarian faunal assemblages and ages in the Northern Alps, Gets nappe, Betic Cordillera, and Site 534 (DSDP Leg 76) suggest a Middle Jurassic connection between the Alpine Tethys and central Atlantic. Biochronologic and isotopic ages currently indicate that oceanic spreading of the Alpine Tethys began during the Bajocian and continued until the Kimmeridgian.

B UCKMAN , S. & AITCHISON, J. C. 2001. Middle Ordovician (Llandeilan) radiolarians from West Junggar, Xinjiang, China. Micropaleontology 47 (4), 359-367. A distinctive long-spined Inaniguttid dominated radiolarian fauna i s present in cherts of the Kekesayi terrane in west Junggar, Xinjiang Province, China. This fauna contains moderately well preserved specimens of Protoceratoikiscum clarksoni on which the presence of caveal ribs and patagial tissue can be observed. Characteristics of the fauna are similar to others of correlative late Middle Ordovician (Llandeilan) age known from Scotland (U.K.) suggesting that Protoceratoikiscum clarksoni may be biostratigraphically useful.

C ARTER, E. S. 2001. Extinction and recovery of radiolarians at the Triassic-Jurassic boundary in Queen Charlotte Islands: implications for global productivity collapse (eds). p. IGCP SW England Workshop, 13-17 October, Abstracts 7. The mass extinction and recovery of radiolarians at the T-J boundary is documented in thick, continuous sections at two localities in Queen Charlotte Islands: Kunga Island and Kennecott Point. Radiolarians are abundant throughout both sequences; accessory faunas include conodonts, and rare ammonites of late Rhaetian and early Hettangian age. The Rhaetian radiolarian fauna is rich and diverse, composed largely of spumellarian and nassellarian genera originating in the late Carnian and Norian. Many distinctive new species arise in the Rhaetian even in the upper beds. Over 65 described species are present at the base of the Globolaxtorum tozeri Zone (the topmost radiolarian zone of the Triassic) on Kunga Island. The abrupt disappearance of this fauna takes place over an interval of ~5 m with over 45 species disappearing in the topmost 1.5 m. Above this level, the fauna is entirely changed. Lower Hettangian beds contain a low diversity fauna composed of simple spumellarians with irregular meshwork and primitive rod-like spines; nassellarians are comparatively rare and unusually small. These radiolarians are assigned to the lower Hettangian Canoptum merum Zone, which i s equivalent to the North American Psilocerras assemblage of the ammonoid standard zonal sequence. Less than twenty genera survive the T-J boundary in Queen Charlotte Islands but not all are present in the lower Hettangian. About half continue to radiate in the Lower Jurassic and beyond, while others are rare and soon disappear. Only about 10 species survive the boundary and nearly all die out in the Hettangian. The faunal sequence at Kennecott Point is similar to Kunga Island, but scarcity of well preserved faunas in tuffaceous boundary beds makes the numbers less striking. Eleven new genera appear in the lower Hettangian and about 30 species gradually accrue from these and other surviving genera; there are no extinctions. Several more genera appear in the middle and upper Hettangian and species diversity gradually rises. Nassellarian diversity increases dramatically in the Sinemurian (especially among multicyrtids), with 65 species recorded by the end of the stage. Throughout this time analogous morphological changes are recognized in the spumellarian population: meshwork becomes more regular, and the simple rod-like spines give way to the more advanced tri-radiate type. The pattern of extinction and recovery seen in radiolarians from Queen Charlotte Islands parallels trends seen in T-J boundary faunas from Japan. This suggests that the end-Triassic microplankton extinction may have been worldwide in extent, a factor likely to affect other groups higher in the food chain.

B RAGIN , N., BRAGINA , L., TUNOGLU, C. & TEKIN, U. K. 2001. The Cenomanian (late Cretaceous) radiolarians from the Tomalar formation, Central Pontides, Northern Turkey. Geologica Carpathica 52 (6), 349-360. The lower part of the Late Cretaceous Tomalar Formation (Devrekani Basin, Central Pontides, northern Turkey) i s characterized by the presence of light-green ribbon cherts and cherty mudstones (approximately 10 m thick) with abundant wellpreserved Radiolaria. The presence and coexistence of such taxa as Acaeniotyle macrospina, Archaeospongoprunum salumi, Becus horridus, Cavaspongia euganea, Dactyliodiscus longispinus, Halesium sexangulum, Hexapyramis pantanellii, Pessagnobrachia irregularis, Pyramispongia glascockensis, Savaryella quadra, Vitorfus brustolensis, Novixitus dengoi, N. weyli, Phalangites telum and others clearly indicate the Cenomanian age. The Tomalar Formation covers the whole Upper Cretaceous due to the presence of Maastrichtian planktonic Foraminifera from the upper part of this formation. The radiolarian assemblage of the Tomalar Formation correlates well with the coeval fauna of the Western Mediterranean.

BRATHAUER, U., ABELMANN, A., GERSONDE, R., et al. 2001. Calibration of Cycladophora davisiana events versus oxygen isotope stratigraphy in the subantarctic Atlantic Ocean; a stratigraphic tool for carbonate-poor Quaternary sediments. Marine Geology 175 (1-4), 167-181.

C ARTER , E. S. 2002. Micropaleontology of radiolarians Proceedings of INTERRAD IX Introduction. Micropaleontology 48, II-II.

We calibrated the Cycladophora davisiana abundances versus oxygen isotope stratigraphy back to 220 ka for the subantarctic Atlantic Ocean. The relative abundances of C. davisiana and ∂ (su1 8 O measurements of benthic and planktic foraminifera have been determined in two sediment cores. Oxygen isotope stratigraphy has been used to date the C. davisiana records and to assign SPECMAP ages to the C. davisiana events. Comparisons with an existing calibration from the subantarctic Indian Ocean show, that the C. davisiana events "b2 , c1 , c2 , d, e1 , e2 , e3 , f, h, i 1 and i 2 " occur synchronous within the errors of the oxygen isotope stratigraphy in the Indian and the Atlantic sectors of the Southern Ocean. Larger

CHIARI, M., MARCUCCI, M. & PRELA, M. 2002. New species of Jurassic radiolarians in the sedimentary cover of ophiolites in the Mirdita area, Albania. Micropaleontology 48, 61-87. 8

Radiolaria 20

Bibliography - 2001-2002

Well-preserved radiolarian faunas have been extracted from twelve sections in Middle and Upper Jurassic cherts of the sedimentary cover of ophiolites in the Mirdita area of northern Albania. The radiolarians are late Bajocian-early Oxfordian in age. Thirty-two radiolarian species are illustrated; thirteen species are described as new, the remainder are discussed informally. The ranges of all taxa are correlated with the Unitary Association Zones (UAZ) of Baumgartner et al. (1995b).

foraminiferal dissolution indices in the Somali Basin. Marine Geology 182 (3-4), 325-349. Two sediment traps moored off Somalia in 1992-1993 collected similar settling fluxes of carbonate and siliceous shells formed by various plankton groups. Planktic foraminifera showed large seasonal variations, with more than 74% of the total planktic foraminifera flux collected during the SW monsoon (summer upwelling), when Globigerina bulloides was dominating along with Globigerinita glutinata and Neogloboquadrina dutertrei . The intermonsoon and NE monsoon assemblages were dominated by Globigerinoides ruber. We used the trap records as our 'no dissolution' reference for comparison with three boxcore recorders in order to quantify the carbonate dissolution along a depth transect. Dissolution increases downslope, from Station 905 to 907 and 915 at depths of 1567 in, 2807 in and 4035 in, respectively. The carbonate fraction of the sediment at Station 915, which is located near the CCD, is the most affected by dissolution, with more than 97% of the planktic foraminifera dissolved. Here, the planktic foraminifera assemblage is strongly modified, with thick walled species such as N. dutertrei, Globorotalia tumida and Pulleniatina obliquiloculata as the most resistant. It i s not representative of the settling assemblage. The planktic foraminiferal assemblages of the sediment surface at Stations 905 and 907 remain similar to the trap assemblages and the foraminifera are well preserved, although only 25% of foraminifera are apparently preserved at Station 905 and 8% at Station 907. Those numbers are surprisingly low and infer that only a small fraction of the foraminiferal carbonate production is buried and removed from the carbon cycle. This discrepancy between the export and buried flux is partly be due to (bio)mechanical destruction by benthic processes and to supralysoclinal dissolution, due to metabolic CO2 generated by the benthic organisms. Another important factor is the interannual variability of the productivity, well known in the Arabian Sea. The calibration of commonly used foraminiferal dissolution indices (percentage of foraminiferal fragments, percentage of resistant species, foraminiferal dissolution index (FDX)) to our data only shows reliable results for high dissolution levels ( > 97%). Off Somalia the most accurate of the proxies is the percentage of foraminiferal fragments compared to the other methods tested, i.e., FDX, planktic foraminiferal loss (L), percentage of radiolarians and diatoms, percentage of benthic foraminifera. The species assemblage appears to be not significantly modified by dissolution unless the estimated shell loss is high, > 92% of the arriving shells in our samples. This level i s expressed in the percentage of fragmentation, the percentage of radiolarians and diatoms, the percentage of resistant foraminifera species, and FDX as 80%, 35%, 25% and 1.8, respectively. The relative abundance of Globigerina bulloides is a valid SW monsoon/upwelling proxy only when dissolution is moderate ( < 92%). Globigerina bulloides and Globigerinoides ruber have similar burial efficiencies and susceptibilities to dissolution. Thus, the ratio G. bulloides/G. ruber is a valid proxy for past changes in the intensity of the SW monsoon even in the strongly dissolved samples. In Our sediment record the ratio G. bulloides/G. ruber indicates that the SW monsoon was stronger in the recent past than in 1992-93.

C LUZEL , D., AITCHISON, J. C. & PICARD , C. 2001. Tectonic accretion and underplating of mafic terranes in the late Eocene intraoceanic fore-arc of New Caledonia (Southwest Pacific); geodynamic implications. Tectonophysics 3 4 0 (1-2), 23-59. This paper deals with the tectonic events that result in the accretion of mafic terranes in the fore-arc region and a close juxtaposition of ultramafic rocks, low grade and high-grade mafic terranes in many collisional orogens. The example is taken from New Caledonia where tectonic accretion, subduction, underplating and obduction of mafic terranes took place during the late Eocene in an intra-oceanic forearc setting. The late Eocene tectonic complex comprised three major terranes: an overlying ultramafic, mainly harzburgitic allochthon named the Ophiolitic Nappe, an intermediate mafic, mainly basaltic off-scraped melange, composed of kilometrescale slices of oceanic upper crust, called the Poya Terrane, parts of which have been metamorphosed into an eclogite/blueschist facies complex, the Pouebo Terrane; and a lower, continental basement formed by the Norkolk Ridge terranes. Based upon exhaustive sampling of the mafic terranes and field surveys, our tectonic, micropaleontologic and geochemical data reveal that Poya and Pouebo terranes rocks originally formed within one single Campanian to late Paleocene oceanic basin, floored by tholeiitic basalt associated with some minor seamount-related intraplate alkali basalt. The tholeiitic basalt displays a continuous range of compositions spanning between "undepleted" and "depleted" endmembers; the former being volumetrically predominant. The overall geochemical and isotopic features indicate an origin from a prominently heterogeneous mantle source during the opening of a marginal basin, the South Loyalty Basin, which almost completely disappeared during Eocene convergence. The opening of this basin originally located to the east of the Norfolk Ridge was synchronous with that of Tasman Sea basin as a consequence of oceanward migration of the west-dipping Pacific subduction zone. Establishing the origin of the ultramafic Ophiolitic Nappe is beyond the scope of this paper; however, it appears to be genetically unrelated to the mafic Poya and Pouebo terranes. Although it was located in the Late Eocene fore-arc, the Ophiolitic Nappe and the corresponding oceanic lithosphere originated before the Late Cretaceous, to the east of the South Loyalty Basin in a back-arc setting; or alternatively in a much older, trapped basin. For reasons that remain unclear, a new east-dipping subduction started in the Eocene and consumed most of the South Loyalty Basin, forming the intra-oceanic Loyalty Arc. Due to a changing subduction regime (underplating of the Diahot Terrane?), the mafic slices that now form the Poya Terrane were tectonically accreted in the Loyalty fore-arc region and remained under low pressure-low temperature conditions (possibly at the subsurface) until the Norfolk Ridge reached the subduction zone diachronously. This resulted in the final obduction of the fore-arc area. The two-step obduction involved first the mafic complex forming the Poya Terrane and thereafter the lithospheric mantle that now forms the Ophiolitic Nappe. In contrast, pieces of the accretionary complex were dragged down into the subduction zone, underplated at depth ca. 70 km and metamorphosed into hightemperature eclogite to form the Pouebo Terrane metamorphics that display the same geochemical features as the Poya Terrane basalt. A mid-to-late Eocene syntectonic piggy-back sedimentary basin (the Nepoui flysch basin) mainly filled with mafic clastic material and shallow water carbonates that record the progressive uplift of the fore-arc region due to the accretion and underplating of mafic ocean-related and other material. In contrast, a slightly younger foreland basin located upon the Norfolk Ridge (the Priabonian Bourail Flysch basin) received a massive input of detrital material derived from the Norfolk Ridge itself and a time-increasing amount of mafic, Poya-derived material that recorded the first step of obduction. Thereafter, the Bourail Flysch was overthrust by the Poya Terrane and finally by the Ophiolitic Nappe. At the same time, buoyancydriven uplift and exhumation of the high-pressure metamorphics.

C ORTESE , G. & A BELMANN, A. 2002. Radiolarian-based paleotemperatures during the last 160 kyr at ODP Site 1089 (Southern Ocean, Atlantic Sector). Palaeogeography Palaeoclimatology Palaeoecology 182 (3-4), 259-286. Two cores, Site 1089 (ODP Leg 177) and PS2821-1, recovered from the same location (40°56'S; 9°54'E) at the Subtropical Front (STF) in the Atlantic Sector of the Southern Ocean, provide a highresolution climatic record, with an average temporal resolution of less than 600 yr. A multi-proxy approach was used to produce an age model for Core PS2821-1, and to correlate the two cores. Both cores document the last climatic cycle, from Marine Isotopic Stage 6 (MIS 6, ca. 160 kyr BP, ka) to present. Summer sea-surface temperatures (SSSTs) have been estimated, with a standard error of ca. +/-1.16°C, for the down core record by using Q-mode factor analysis (Imbrie and Kipp method). The paleotemperatures show a 7°C warming at Termination II (last interglacial, transition from MIS 6 to MIS 5). This transition from glacial to interglacial paleotemperatures (with maximum temperatures ca. 3°C warmer than present at the core location) occurs earlier than the corresponding shift in ∂1 8O values for benthic foraminifera from the same core; this suggests a lead of Southern Ocean paleoteraperature changes compared to the global ice-volume changes, as indicated by the benthic isotopic record. The climatic evolution of the record continues with a progressive temperature

C ONAN , S. M. H., IVANOVA, E. M. & BRUMMER, G. J. A. 2002. Quantifying carbonate dissolution and calibration of

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deterioration towards MIS 2. High-frequency, millennial-scale climatic instability has been documented for MIS 3 and part of MIS 4, with sudden temperature variations of almost the same magnitude as those observed at the transitions between glacial and interglacial times. These changes occur during the same time interval as the Dansgaard-Oeschger cycles recognized in the ∂ 1 8O(ice) record of the GRIP and GISP ice cores from Greenland, and seem to be connected to rapid changes in the STF position in relation to the core location. Sudden cooling episodes ('Younger Dryas (YD)-type' and 'Antarctic Cold Reversal (ACR)-type' of events) have been recognized for both Termination I (ACR-I and YD-I events) and II (ACR-II and YD-II events), and imply that our core i s located in an optimal position in order to record events triggered by phenomena occurring in both hemispheres. Spectral analysis of our SSST record displays strong analogies, particularly for high, suborbital frequencies, to equivalent records from Vostok (Antarctica) and from the Subtropical North Atlantic ocean. This implies that the climatic variability of widely separated areas (the Antarctic continent, the Subtropical North Atlantic, and the Subantarctic South Atlantic) can be strongly coupled and co-varying at millennial time scales (a few to 10-ka periods), and eventually induced by the same triggering mechanisms. Climatic variability has also been documented for supposedly warm and stable interglacial intervals (MIS 1 and 5), with several cold events which can be correlated to other Southern Ocean and North Atlantic sediment records.

This paper presents new radiolarian biostratigraphic and igneous/metamorphic geochemical data for a Mesozoic volcanic–sedimentary mélange on the island of Evia (Euboea or Evvoia), eastern Greece. This mélange includes dismembered thrust sheets and blocks of radiolarian chert and basalt. Biostratigraphic age data show that radiolarites interbedded with basalt-derived, coarse clastic sediments near the base of a coherent succession were deposited in Middle and Late Triassic time (Late Ladinian–Carnian, Norian?). Geochemical evidence shows that associated extrusive rocks, of inferred Triassic age, range from ‘enriched’ alkaline basalts, to ‘transitional’ basalts, and more ‘depleted’ mid-ocean ridge-type basalts. Amphibolite facies metabasalts from the metamorphic sole of the over-riding Evia ophiolite exhibit similar chemical compositions. Both the basalts and the meta-basalts commonly show an apparent subduction-related influence (e.g. relative Nb depletion) that may have been inherited from a previous subduction event in the region. The basalts are interpreted to have erupted during Middle–Late Triassic time (Late Ladinian–Carnian), related to initial opening of a Neotethyan ocean basin adjacent to a rifted continental margin. Radiolarites located stratigraphically higher in the coherent succession studied are dated as Middle Jurassic (Late Bathonian–Early Callovian). Similaraged radiolarites are depositionally associated with ophiolitic rocks (including boninites), in some other areas of Greece and Albania. During initial ocean basin closure (Bajocian–Bathonian) the adjacent shallow-water carbonate platform (Pelagonian zone) disintegrated to form basins in which siliceous sediments were deposited and highs on which shallow-water carbonates continued to accumulate. This facies differentiation is seen as a response to crustal flexure as the Neotethyan ocean began to close. The over-riding Pagondas Mélange and other similar units in the region are interpreted as accretionary prisms related to subduction of Neotethyan oceanic crust in Middle–Late Jurassic time. These mélanges were emplaced, probably diachronously during Oxfordian–Kimmeridgian time, when the passive margin collapsed, creating a foredeep ahead of advancing thrust sheets of mélange and ophiolites.

C ORTESE , G., BJØRKLUND, K. R. & DOLVEN , J. K. in press. Polycystine Radiolarians in the Greenland-IcelandNorwegian (GIN) Seas: Species and assemblage distribution. Sarsia. Cluster Analysis and Q-mode Factor Analysis have been applied to polycystine radiolarians census data from 160 coretop samples. This allowed us to recognize four faunal assemblages in the GIN Seas, each related to different oceanographic conditions. A regression equation for deriving paleotemperatures from these assemblages has also been developed. The standard error of estimate for this equation is ± 1.2 °C. The relative abundance of the species having the higher loadings in the coretop assemblages has been mapped, in order to identify and analyse water mass and environmental requirements for these species. Cluster Analysis has also been performed on the same dataset, providing results which are in good harmony with those derived by Q-mode Factor Analysis.

D E N G , X. & U NDERWOOD , M. B. 2001. Abundance of smectite and the location of a plate-boundary fault, Barbados accretionary prism. Geological Society o f America Bulletin 113 (4), 495-507. Isolating the respective roles of factors responsible for the initiation and localization of fault zones remains one of the more important goals of research in neotectonics. The frontal decollement zone of the northern Barbados accretionary prism provides several important clues as to how the interwoven variables of clay mineralogy, fluid flow, chemical interactions, and sediment physical properties affect strain localization. This plate-boundary fault is centered at a lithologic contact between Miocene claystone and fine-grained Oligocene turbidites. The fault zone is nearly 40 m thick (at Ocean Drilling Program Site 948), and its upper part passes through smectite-rich deposits. A sharp minimum in percent smectite and a maximum in percent illite mark the base of the decollement. There is a consistent increase in percent smectite with distance above the base of the decollement, but the top of the decollement is poorly defined by clay mineralogy. The intrinsic mechanical weakness of strata with abundant smectite-group clays probably influences where the fault tip propagates into the undeformed stratigraphy of the Atlantic abyssal plain. A second inherited parameter is the local abundance of radiolarians, which contribute to higher than normal porosities. Sediment shear strength also decreases because pore pressure within the fault zone is significantly greater than hydrostatic. The principal cause of excess pore pressure seems to be updip fluid advection; in theory, however, decreases in pore-fluid salinity and porosity collapse should increase the amount of physicochemical stress generated by expandable clay minerals. The imported fluid is unusually low in salinity because it has migrated from zones of deeper seated dehydration reactions. If fresher pore water migrates to the propagating tip of the decollement, its arrival should increase smectite swelling and reduce the shear strength of the mudstone even more. The location and evolution of the decollement, therefore, are controlled by a complicated interplay of static factors inherited from the abyssal Atlantic stratigraphy and dynamic factors associated with episodic fluid flow and changing fluid chemistry.:Isolating the respective roles of factors responsible for the initiation and localization of fault zones remains one of the more important goals of research in neotectonics. The frontal decollement zone of the northern Barbados accretionary prism provides several important clues as to how the interwoven variables of clay mineralogy, fluid flow, chemical interactions, and sediment physical properties affect strain localization. This plate-boundary fault is centered at a lithologic contact between Miocene claystone and fine-grained Oligocene turbidites. The fault zone is nearly 40 m

DANELIAN, T. & JOHNSON, K. G. 2001. Patterns of biotic change in Middle Jurassic to Early Cretaceous Tethyan Radiolaria. Marine Micropaleontology 43 (3-4), 239-260. The rate of taxic turnover of nearly 400 radiolarian species/subspecies is analyzed in order to document long term biotic change of plankton during the Middle Jurassic to Early Cretaceous (Aalenian to Aptian). The pattern and dynamic of diversity change is described using four indices: rate of species first and last occurrence, rate of diversification and rate of turnover. Plots of cumulative sampling effort suggest that the analyzed data represent an adequate sample of total standing diversity for most examined stages. Rates of species first occurrence exceed rates of last occurrence for most of the Middle Jurassic, except for the middle Bajocian. In contrast, the Late Jurassic was a time of decreasing radiolarian diversity and the Kimmeridgian records the lowest rate of diversification. It i s followed by a dramatic increase in first occurrences near the Jurassic-Cretaceous boundary with as a result the highest rate of diversification recorded in the late Tithonian. Regional radiolarian diversity was stable throughout most of the Early Cretaceous. A stratigraphic permutation test was performed to assess the influence of uneven sampling on the observed pattern of taxic turnover and identified the intervals for which randomly obtained patterns are significantly different from the observed pattern. The Kimmeridgian and late Tithonian events coincide with substantial climate-derived perturbations in water cycling, nutrient supply and oceanic productivity. They point to a negative relationship between radiolarian macroevolution and changes in the state of nutrient availability, although further work is needed to refine the temporal resolution of this relationship and to explore ecological aspects of its causal link with respect to radiolarian evolution.

D ANELIAN , T. & ROBERTSON , A. H. F. 2001. Neotethyan evolution of eastern Greece (Pagondas Melange, Evia Island) inferred from radiolarian biostratigraphy and the geochemistry of associated extrusive rocks. Geological Magazine 138 (3), 345-363. 10

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Bibliography - 2001-2002

thick (at Ocean Drilling Program Site 948), and its upper part passes through smectite-rich deposits. A sharp minimum in percent smectite and a maximum in percent illite mark the base of the decollement. There is a consistent increase in percent smectite with distance above the base of the decollement, but the top of the decollement is poorly defined by clay mineralogy. The intrinsic mechanical weakness of strata with abundant smectite-group clays probably influences where the fault tip propagates into the undeformed stratigraphy of the Atlantic abyssal plain. A second inherited parameter is the local abundance of radiolarians, which contribute to higher than normal porosities. Sediment shear strength also decreases because pore pressure within the fault zone is significantly greater than hydrostatic. The principal cause of excess pore pressure seems to be updip fluid advection; in theory, however, decreases in pore-fluid salinity and porosity collapse should increase the amount of physicochemical stress generated by expandable clay minerals. The imported fluid is unusually low in salinity because it has migrated from zones of deeper seated dehydration reactions. If fresher pore water migrates to the propagating tip of the decollement, its arrival should increase smectite swelling and reduce the shear strength of the mudstone even more. The location and evolution of the decollement, therefore, are controlled by a complicated interplay of static factors inherited from the abyssal Atlantic stratigraphy and dynamic factors associated with episodic fluid flow and changing fluid chemistry.

We have examined the history of the elevated primary productivity associated with the Benguela Current upwelling system off southwest Africa using sediments from 7.5 to 4.8 Ma at Ocean Drilling Program Site 1085 in the middle Cape Basin. Sedimentation rates are low until 6.9 Ma. Low accumulation rates of benthic foraminifers and organic carbon indicate that biological productivity was also low. Paleoproductivity dramatically increased at 6.7-6.5 Ma and was highly variable until 4.8 Ma with productivity maxima during cooler periods. The presence of radiolarian opal only between 5.8 and 5.2 Ma suggests an interlude of silica-rich intermediate water in the Cape Basin. The onset of heightened productivity under the Benguela Current is mirrored by similar increases reported between 6.9 and 6.7 Ma in the tropical eastern Pacific, the western and northern Pacific, and the Indian Ocean. The similarity between the patterns at Site 1085 and in the Pacific and Indian Oceans suggests that the dramatic productivity increase off southwest Africa is part of a global response to paleoceanographic changes.

DIESTER, H. L., MEYERS, P. A., VIDAL, L., et al. 2002b. Sand fraction, carbonate, and organic carbon contents of late Miocene sediments from Site 1085, middle Cape Basin. In: (BERGER WOLFGANG, H., WEFER, G., et al. eds). Proceedings of the Ocean Drilling Program, scientific results, Benguela Current; covering Leg 175 of the cruises of the drilling vessel JOIDES Resolution; Las Palmas, Canary Islands, t o Cape Town, South Africa; sites 1075-1087; 9 August-8 October 1997. Texas A&M University, Ocean Drilling Program. College Station, TX, United States

D I S TEFANO, P., GALACZ, A., MALLARINO, G., et al. 2002. Birth and early evolution of a Jurassic escarpment: Monte Kumeta, Western Sicily. Facies 46, 273-298.

Site 1085 is located on the continental rise of southwest Africa at a water depth of 1713 m off the mouth of the Orange River in the Cape Basin. The site is part of the suite of locations drilled during Leg 175 on the Africa margin to reconstruct the onset and evolution of the elevated biological productivity associated with the Benguela Current upwelling system (Wefer, Berger, Richter, et al., 1998). Three sediment samples were collected per section from Cores 170-1085A-28H through 45X (251-419 mbsf) to provide a survey of the sediment record of paleoproductivity from the middle late Miocene to the early Pliocene (~8.7-4.7 Ma), which is a period that includes the postulated northward migration and intensification of the Benguela Current and the establishment of modern circulation off southwest Africa (Siesser, 1980; Diester-Haass et al., 1992; Berger et al., 1998). Core 170-1085A-30H (270-279 mbsf) had essentially no recovery; this coring gap was filled with samples from Cores 170-1085B-29H and 30H (261-280 mbsf). The results of measurements of multiple paleoproductivity proxies are summarized in this report. Included in these proxies are the radiolarian, foraminiferal, and echinoderm components of the sandsized sediment fraction. Opal skeletons of radiolarians (no diatoms were found) relate to paleoproductivity and water mass chemistry (Summerhayes et al., 1995; Lange and Berger, 1993; Nelson et al., 1995). The accumulation rates of benthic foraminifers are useful proxies for paleoproductivity (Herguera and Berger, 1991; Nees, 1997; Schmiedl and Mackensen, 1997) because these fauna subsist on organic matter exported from the photic zone. Echinoderms also depend mainly on food supply from the photic zone (Gooday and Turley, 1990), and their accumulation rates are an additional paleoproductivity proxy. Concentrations of calcium carbonate (CaCO3) and organic carbon in sediment samples are fundamental measures of paleoproductivity (e.g., Meyers, 1997). In addition, organic matter atomic carbon/nitrogen (C/N) ratios and 13C values can be used to infer the origin of the organic matter contained within the sediments and to explore some of the factors affecting its preservation and accumulation (Meyers, 1994).Site 1085 is located on the continental rise of southwest Africa at a water depth of 1713 m off the mouth of the Orange River in the Cape Basin. The site is part of the suite of locations drilled during Leg 175 on the Africa margin to reconstruct the onset and evolution of the elevated biological productivity associated with the Benguela Current upwelling system (Wefer, Berger, Richter, et al., 1998). Three sediment samples were collected per section from Cores 170-1085A-28H through 45X (251-419 mbsf) to provide a survey of the sediment record of paleoproductivity from the middle late Miocene to the early Pliocene (~8.7-4.7 Ma), which is a period that includes the postulated northward migration and intensification of the Benguela Current and the establishment of modern circulation off southwest Africa (Siesser, 1980; Diester-Haass et al., 1992; Berger et al., 1998). Core 170-1085A-30H (270-279 mbsf) had essentially no recovery; this coring gap was filled with samples from Cores 170-1085B-29H and 30H (261-280 mbsf). The results of measurements of multiple paleoproductivity proxies are summarized in this report. Included in these proxies are the

The accurate reconstruction of the facies architecture in the Jurassic succession of Monte Kumeta, coupled with a detailed biostratigraphy, allow to define dynamics and genetic factors controlling the conversion of a Bahamian-type carbonate platform to a pelagic escarpment. A change from tidalites to oolites i.e. from the restricted, interior lagoon to a more open-marine sandy depositional environment, records the establishment of a basin south of the Monte Kumeta sector in late Hettangian-Sinemurian times. The oolitic limestones are overlain by earliest Carixian bioclastic grainstones and packstones with micritized grains and by wackestones with radiolarians and sponge spicules, organized in thin sand prisms. The decrease of carbonate productivity indicated by these sediments records the dissection of the platform and the subsequent isolation of a submarine topographic high in the Monte Kumeta sector. Though based only on indirect evidence, it i s suggested that a tectonically controlled scarp must have existed between the Monte Kumeta "high" and the basin. Progressive northward retreat of this scarp resulted in the conversion of a shallow platform sector into a gradually steepening slope, along which the distribution of sediments was controlled by repeated tectonic and gravity-induced modifications of the topography of the substrate. Vertical and lateral changes and geometrical relationships of the recognized lithofacies suggest that they were deposited on a stepped surface brought about mainly by, repeatedly reactivated basin ward dipping normal faults. This scenario i s clearly reflected by the relationship of platform strata and the overlying encrinites of Carixian/ Domerian age. The encrinite bodies show again a prismatic geometry, becoming thicker towards the south and filling the first generation of neptunian dykes. The top of the encrinites is marked by a peculiar jagged dissolution surface with dm-scale pinnacles capped by a thick ferromanganese crust. The formation of this peculiar surface could have been controlled by complex changes in water chemistry probably related to the Early Toarcian anoxic event. The crust itself is dissected by faults of decimetres to metres of throw, sometimes organized into smallscale positive flower structures. In the hollows/depressions of this highly articulated substrate pelagic sediments of Bajocian to Oxfordian age were deposited. They display a clearly onlapping relationship to the encrinites and to the carbonate platform beds. Their thickness rarely exceeds 4 to 5 meters and they are present also as neptunian dykes filling a dense network of fissures. During Late Callovian and Oxfordian times synsedimentary tectonics has intensified resulting in an increase of the inclination of the slope. This led to more and more abundant, gravitationally controlled deformations (slumping and sliding) of semi-lithified and unlithified sediments along the Monte Kumeta escarpment.

DIESTER, H. L., MEYERS, P. A. & VIDAL, L. 2002a. The late Miocene onset of high productivity in the Benguela Current upwelling system as part of a global pattern. Marine Geology 180 (1-4), 87-103.

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radiolarian, foraminiferal, and echinoderm components of the sandsized sediment fraction. Opal skeletons of radiolarians (no diatoms were found) relate to paleoproductivity and water mass chemistry (Summerhayes et al., 1995; Lange and Berger, 1993; Nelson et al., 1995). The accumulation rates of benthic foraminifers are useful proxies for paleoproductivity (Herguera and Berger, 1991; Nees, 1997; Schmiedl and Mackensen, 1997) because these fauna subsist on organic matter exported from the photic zone. Echinoderms also depend mainly on food supply from the photic zone (Gooday and Turley, 1990), and their accumulation rates are an additional paleoproductivity proxy. Concentrations of calcium carbonate (CaCO3) and organic carbon in sediment samples are fundamental measures of paleoproductivity (e.g., Meyers, 1997). In addition, organic matter atomic carbon/nitrogen (C/N) ratios and 13C values can be used to infer the origin of the organic matter contained within the sediments and to explore some of the factors affecting its preservation and accumulation (Meyers, 1994).

Polycystine radiolarians are used to reconstruct summer sea surface temperatures (SSST) for the Late Pleistocene-Holocene (600-13,400 14C yrs. BP) in the Norwegian Sea. At 13,200 14C yrs. BP, SSST was close to the average Holocene SSST (~12°C). It then gradually dropped to 7.1°C in the Younger Dryas. At the Younger Dryas-Holocene transition (~10,000 14C years BP), SSST increased to 12°C in ca. 530 years. Four abrupt cooling events, with temperature drops of up to 2.1°C, are recognized during the Holocene: at 9,340, 7,100 (“8,200 calendar yrs. event”), 6,400 and 1,650 14C yrs. BP. Radiolarian SSSTs and the isotopic signal from the GISP2 ice core are strongly coupled, stressing the importance of the Norwegian Sea as a mediator of heat/precipitation exchange between the North Atlantic, the atmosphere, and the Greenland ice sheet. Radiolarian and diatom derived SSST display similarities, with the former not showing the recently reported Holocene cooling trend.

D ONG, W. Q., LAL, D., RANSOM, B., et al. 2001. Marine biogeochemistries of Be and Al: A study based o n cosmogenic Be-10, Be and Al in marine calcite, aragonite, and opal. Proceedings of the Indian Academy of SciencesEarth and Planetary Sciences 110 (2), 95-102.

DIESTER, H. L. & ZAHN, R. 2001. Paleoproductivity increase at the Eocene-Oligocene climatic transition; ODP/ DSDP sites 763 and 592. Palaeogeography, Palaeoclimatology, Palaeoecology 172 (1-2), 153-170. During the late Eocene-early Oligocene period of rapid climate change (across Oxygen isotope shift Oi-1) productivity showed major changes in the region around Australia (DSDP Site 592 off New Zealand, ODP Site 763 off NW Australia). We estimated paleoproductivity at these sites using benthic foraminiferal accumulation rates, as well as accumulation rates of siliceous and other calcareous microfossils, and carbon isotope data. In the Eocene productivity was generally higher at Site 763, where it reached 4 maxima, but dropped at about 34.3 Ma. At both sites productivity increased strongly at Oi-1 (as recognized in the oxygen isotopic record at the sites), and fluctuated during the early Oligocene at higher levels than in the Eocene. We attribute the difference in Eocene productivity to differences in oceanographic settings: Site 592 was probably under a N-S flowing western boundary current of the Pacific gyre, whereas Site 763 showed periodic high productivity as a result of local upwelling. This upwelling occurred when a warm, N-S flowing current (proto-Leeuwin current) replaced the cold, S-N flowing eastern boundary current of the Indian Ocean gyre. Upwelling ended at the opening of the Tasman Sea. The earliest Oligocene increase in productivity occurred at many other locations in the Southern Oceans, and is accompanied by a strong increase in carbon isotopic values, indicating increased burial of organic matter on a global scale. This productivity increase as well as the increased burial indicates that the oceanic carbon cycle may have been part of the climate change in the earliest Oligocene.

The geochemical behaviors of Be and Al in ocean waters have been successfully studied in recent years using natural, cosmogenic, radioactive Be-10 and Al-26 as tracers. The present day dissolved concentrations and distribution of the stable and radioactive isotopes of Be and Al in ocean waters have revealed their short residence times and appreciable effects of exchange fluxes at the coastal and ocean-sediment interfaces. It follows that concentrations of these particle-active elements must have varied in the past with temporal changes in climate, biological productivity and aeolian flux of continental detritus to the oceans. We therefore investigated the feasibility of extending the measurements of Be and At isotope concentrations in marine systems to the 103 -106 y BP time scale. We report here the discovery of significant amounts of intrinsic Be and Al in marine foraminiferal calcite and coral aragonite, and of Al in opal (radiolarians) and aragonite (coral), which makes it possible to determine Be-10/Be and Al-26/Al in oceans in the past. We also report measured Be-10/Be-9 in foraminiferal calcite in Pacific Ocean cores, which reveal that the concentrations and ratios of the stable and cosmogenic isotopes of Be and Al have varied significantly in the past 30 ky. The implications of these results are discussed.

DUMITRICA, P. 2001. On the status of the radiolarian genera Gonosphaera Jorgensen and Excentroconcha Mast. Revue de Micropaleontologie 44 (3), 191-198. The study of the initial skeleton of Gonosphaera JORGENSEN proves that this genus is not a nassellarian taxon as initially and later considered, but an entactinarian radiolarian belonging to the family Excentroconchidae. It has an initial spicule with a median bar, two apical spines, four basal spines, two basal arches connecting the basal spines on both sides of MB, and a transversal antapical arch connecting medially the two basal arches and bearing two antapical spines. The genus Excentroconcha MAST has the same type of initial skeleton as Gonosphaera and could be considered a junior synonym of the latter. The diagnosis of the family Excentroconchidae and of the two genera is discussed and emended.

D O L V E N , J. K. & BJ O R K L U N D , K. R. 2001. An early Holocene peak occurrence and recent distribution of Rhizoplegma boreale (Radiolaria); a biomarker in the Norwegian Sea. Marine Micropaleontology 4 2 (1-2), 2544. Several sediment cores in the Norwegian Sea reveal, in the early Preboreal, abundance peaks of up to 14% of Rhizoplegma boreale (Cleve). These peaks generally coincide with a transition from cold to warm water radiolarian assemblages and a high number of diatom valves (Chaetoceros sp.), indicating highly productive surface waters. The R. boreale peak represents an ecological event caused by an influx of North Atlantic Water, and can potentially be used as a chrono-stratigraphic marker within the eastern part of the Norwegian Sea. In core HM 79-6.2 the R. boreale peak reaches 9.2%, and is found between two 1 4C-dated ash layers. We estimated the age of the R. boreale peak to be 9880+ or -55 yr BP by linear interpolation between datum points. The characteristic stratigraphical distribution of R. boreale was used to establish a better age model for the studied section. Rhizoplegma boreale has been mapped in surface sediment samples from the Iceland Sea, the Norwegian Sea and the Norwegian fjords. An oceanic form with six and a neritic form with eight radial spines were found in these areas. Recent distribution of Rhizoplegma boreale is mainly confined to the Nordic Seas (Greenland, Iceland, and Norwegian Seas), the North Pacific (including the Bering Sea and Sea of Okhotsk) and in the Southern ocean. The highest occurrence of R. boreale is found in areas with high primary production and mixing of water masses.

DUMITRICA, P. & ZUGEL, P. 2002. Mendacastrum n. gen. and Domuzdagia n. gen., two Jurassic spherical Spumellaria (Radiolaria) with hagiastrid medullary shell. Micropaleontology 48, 23-34. Two new spumellarian radiolarian genera, Mendacastrum and Domuzdagia, are described from the lower Tithonian and lower Pliensbachian respectively. Both have a spherical cortical shell of actinommid type and a spherical or subspherical double medullary shell with the inner medullary shell of hagiastrid s.l. type. The inner medullary shell of M e n d a c a s t r u m is of dactyliosphaerid or higumastrid s. sit. type, whereas that of D o m u z d a g i a is of angulobracchiid type. Since they cannot be assigned to any described Mesozoic pyloniacean families, they are considered as type genera of two new families: Mendacastridae and Domuzdagiidae respectively.

DUMOULIN, J. A., HARRIS, A. G., YOUNG, L. E. & BLOME, C. D. 2001. Sedimentologic and paleontologic constraints o n setting and age of the Red Dog Zn-Pb-Ag massive sulfide deposit, western Brooks Range, Alaska. In: (A NONYMOUS

DOLVEN, J. K., CORTESE, G. & BJØRKLUND, K. R. in press. A high-resolution radiolarian derived paleotemperature record for the Late Pleistocene-Holocene in the Norwegian Sea. Paleoceanography. 12

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Bibliography - 2001-2002 Australia moved northward from Antarctica. Initially, the site was at the far eastern end of the restricted Australo-Antarctic Gulf and separated from the Pacific Ocean by the Tasmanian land bridge. Plate movements and related margin subsidence led to its Neogene location in open water facing a broad Southern Ocean. The primary objectives were to core and log (1) a prograding detrital sequence, formed during Eocene opening of the ocean south of Australia, for its paleoceanographic, paleoclimatic, and biotic history, (2) an Oligocene to present-day pelagic carbonate sequence for better understanding of the evolution of the Southern Ocean during its expansion in the Cenozoic and for high-resolution paleoclimatic studies, and (3) a Cenozoic sequence for high-resolution biostratigraphic studies.

eds). Geological Society of America, 2001 annual meeting Abstracts 33(6): 272. Geological Society of America (GSA). Boulder, CO, United States. 2001. The upper Kuna Formation (Lisburne Group) in northwest Alaska hosts the giant Red Dog and related Zn-Pb-Ag massive sulfide deposits; our studies of Kuna sedimentology and paleontology constrain the setting, age, and thermal history of these deposits. The upper Kuna in the Red Dog area (Ikalukrok unit) is mainly finely laminated, black siliceous shale and mudstone, locally rich in sponge spicules and radiolarians. Mean total organic carbon (TOC) content is 4.6 wt %. Locally abundant carbonate layers are of two types: calcareous radiolarite (calcite-replaced radiolarians in a carbonate matrix) and fine to coarse sand-sized calcareous lithic turbidites. Turbidites (2 cm to >4 m thick) were derived from a mix of shallowand deep-water sources; they consist of carbonate (50%), quartz (5-30%), and other non-carbonate material (20-50%), including mud, lithic clasts, and phosphatic grains. Some turbidites lack carbonate. Similar lithofacies occur in the Kuna and related units approximately 120-200 km to the east (Howard Pass quadrangle), where TOC contents average 3.7 wt % and P2 O (sub 5) values reach 7.7 wt %. Sedimentologic, faunal, and geochemical data suggest that Kuna deposition in the Red Dog and Howard Pass areas took place mainly in basin and slope settings characterized by anoxic or dysaerobic bottom waters and locally high organic productivity (possibly related to upwelling). Conodonts and radiolarians indicate an age range of Osagean-Chesterian (late Early-Late Mississippian) for the Ikalukrok. Carbonate input into the Ikalukrok basin occurred chiefly during middle Osagean (Sc. anchoralis-Do. latus Zone) and late Meramecian-early Chesterian time, and ceased when adjacent carbonate platforms drowned. Conodont color alteration indices (CAI) for the Kuna in the Red Dog area are mostly 3.0 or 3.5, indicating temperatures of at least 120-200°C; tectonic burial and (or) an elevated geothermal gradient are needed to explain these CAI values.

EXON, N. F., KENNETT, J. P., MALONE, M. J., et al. 2001b. Site 1169. In: (EXON NEVILLE, F., KENNETT JAMES, P., et al. eds). Proceedings of the Ocean Drilling Program, initial reports, the Tasmanian Gateway, Cenozoic climatic and oceanographic development; covering Leg 189 of the cruises of the drilling vessel JOIDES Resolution; Hobart, Tasmania, to Sydney, Australia; sites 1168-1172, 1 1 March-6 May 2000. Texas A & M University, Ocean Drilling Program. College Station, TX, United States Site 1169 is located in deep water (3568 m) in a flat plain on the western part of the South Tasman Rise (STR), 400 km south of Tasmania. It lies 30 km east of the ridge of the Tasman Fracture Zone (TFZ) that rises 400 m above the plain. The site is ~100 km south of the Subtropical Front (Subtropical Convergence). At Site 1169 we planned to penetrate open-ocean carbonate oozes deposited from the Miocene onward as Australia moved northward from Antarctica. In the early Miocene (20 Ma), the site was at 55°S compared to its present latitude of 47°S. The primary objective was to core a complete upper Neogene sequence with high sedimentation rates in northern subantarctic waters for high-resolution biostratigraphic and paleoclimate investigations.

E D E R , V. G., KR A S A V C H I K O V , V. O., ZA N I N , Y. N. & Z AMIRAILOVA, A. G. 2001. Organic carbon versus major elements relationship in rocks of the Bazhenov Formation, western Siberia. Lithology and Mineral Resources 3 6 (3), 236-242.

E XON , N. F., KENNETT , J. P., MALONE , M. J., et al. 2001c. Site 1170. In: (EXON NEVILLE, F., KENNETT JAMES, P., et al. eds). Proceedings of the Ocean Drilling Program, initial reports, the Tasmanian Gateway, Cenozoic climatic and oceanographic development; covering Leg 189 of the cruises of the drilling vessel JOIDES Resolution; Hobart, Tasmania, to Sydney, Australia; sites 1168-1172, 1 1 March-6 May 2000. Texas A & M University, Ocean Drilling Program. College Station, TX, United States

A close relation of the organic carbon (Corg) content with major has been established for rocks of the Upper Jurassic-Lower Cretaceous Bazhenov Formation. Applying the method of multiple linear regression, it has been demonstrated that the C org content in rocks of the Bazhenov Formation is stringently controlled by its bulk chemical composition. This inference is consistent with the existing ideas regarding a close interrelation between the following main components of rocks: organic carbon and authigenic quartz formed on remains of Radiolaria; pyrite formed in a highly reducing medium of Corg-rich sediments; and terrigenous clayey material diluting the authigenic siliceous-carbonaceous-pyritic matrix. These components chiefly determine the spectrum of major elements in the Bazhenov Formation. The establishment of the close relation between the Corg content and the group of major elements refutes the suggestion of some authors that siliceous material was supplied to nonlithified sediments of the Bazhenov sea by hydrothermal solutions, because this mechanism would have inevitably upset geochemical relations between elements in the studied rocks.

Site 1170 is located in deep water (2704 m) on the flat western part of the South Tasman Rise (STR), 400 km south of Tasmania and 40 km east of Site 1169. It is 10 km west of a fault scarp, ~500 m high and trending north-south, that separates the lower western and higher central blocks of the STR. The site lies within present-day northern subantarctic surface waters, ~150 km south of the Subtropical Front and well north of the Subantarctic Front. The primary objectives of Site 1170 were to core and log (1) an Eocene detrital section deposited during early rifting between the STR and Antarctica to ascertain marine paleoenvironmental conditions before and leading into the initial marine connection that developed between the southern Indian and Pacific Oceans as the Tasmanian gateway opened during the mid-Paleogene, (2) an Oligocene to Holocene pelagic carbonate sequence to document the paleoceanographic and paleoclimatic responses to the opening of the Tasmanian gateway and subsequent expansion of the Southern Ocean, and (3) an upper Neogene sequence to construct a highresolution subantarctic biostratigraphy and a high-resolution record of paleoclimatic change.

E XON , N. F., KENNETT , J. P., MALONE , M. J., et al. 2001a. Site 1168. In: (EXON NEVILLE, F., KENNETT JAMES, P., et al. eds). Proceedings of the Ocean Drilling Program, initial reports, the Tasmanian Gateway, Cenozoic climatic and oceanographic development; covering Leg 189 of the cruises of the drilling vessel JOIDES Resolution; Hobart, Tasmania, to Sydney, Australia; sites 1168-1172, 1 1 March-6 May 2000. Texas A & M University, Ocean Drilling Program. College Station, TX, United States

E XON , N. F., KENNETT , J. P., MALONE , M. J., et al. 2001d. Site 1171. In: (EXON NEVILLE, F., KENNETT JAMES, P., et al. eds). Proceedings of the Ocean Drilling Program, initial reports, the Tasmanian Gateway, Cenozoic climatic and oceanographic development; covering Leg 189 of the cruises of the drilling vessel JOIDES Resolution; Hobart, Tasmania, to Sydney, Australia; sites 1168-1172, 1 1 March-6 May 2000. Texas A & M University, Ocean Drilling Program. College Station, TX, United States

Site 1168 is located in middle bathyal water depths (2463 m) on the 4° slope of the western margin of Tasmania (70 km from coast) in a 25-km-wide strike-slip basin between upthrown northwesttrending ridges of Cretaceous rocks. The western Tasmania onshore margin was uplifted during the late Paleocene and early Eocene (O'Sullivan and Kohn, 1997), and this uplift and the strike-slip motion were probably coeval. The site is 80 km southeast of Deep Sea Drilling Project (DSDP) Site 282, which is located in deeper water and on a structural high. It lies north of the oceanographic Subtropical Front. Site 1168 was planned to penetrate marine rift to open-margin sediments deposited from the Eocene onward as

Site 1171 is located in lower bathyal water depths of ~2150 m on a gentle southwesterly slope on the southernmost South Tasman Rise (STR), ~550 km south of Tasmania and 270 km southeast of Site

13

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Radiolaria 20

1170. At 48°30´S, Site 1171 lies in subantarctic waters between the Subtropical Convergence and the Subantarctic Front. In this area, very strong surface and bottom currents are associated with the Antarctic Circumpolar Current. The major objectives were to (1) core and log an Oligocene to Holocene pelagic carbonate section to evaluate expected major paleoceanographic and paleoclimatic effects resulting from the opening of the Tasmanian Gateway near the time of the Eocene/Oligocene boundary and later development of deep Antarctic Circumpolar Current flow; (2) core and log an expected underlying detrital sedimentary Eocene sequence to evaluate paleoenvironmental conditions during rifting of the STR from Antarctica; and (3) obtain high-resolution sedimentary records from critical subantarctic latitudes to better understand the role of the Southern Ocean in climate changes during the Neogene.

of Simao, however, is characterized by low SiO2 content, low ratios of MnO/TiO2 (0.27) and high ratios of Al/(Al+Fe+Mn) (0.49) and Ce/Ce*(0.88), which imply that the chert was deposited in continental margin basin. The basalts from the both areas belong to tholeiite series, and the chemical compositions of their major, rare earth and trace elements show the characteristics of MORB. These results evidence that there are volcanic rocks and chert sequences representing pelagic basin and oceanic basin near continent. These sequences and the formerly reported island-arc volcanic rock sequences imply that the Daxinshan Formation in the Lancangjiang belt represents a sedimentary assemblage formed in active continental margin basin.

FENG, Q. L., ZHANG, Z. F. & YE, M. 2001c. Middle Triassic radiolarian fauna southwest Y u n n a n , China. Micropaleontology 47 (3), 173-204.

E XON , N. F., KENNETT , J. P., MALONE , M. J., et al. 2001e. Site 1172. In: (EXON NEVILLE, F., KENNETT JAMES, P., et al. eds). Proceedings of the Ocean Drilling Program, initial reports, the Tasmanian Gateway, Cenozoic climatic and oceanographic development; covering Leg 189 of the cruises of the drilling vessel JOIDES Resolution; Hobart, Tasmania, to Sydney, Australia; sites 1168-1172, 1 1 March-6 May 2000. Texas A & M University, Ocean Drilling Program. College Station, TX, United States

A highly diverse radiolarian fauna of Anisian age has been recovered from an 11m continuous succession of siliceous rocks with tuffs and mudstones in the Changning-Menglian belt of southwestern Yunnan, China. Seventy-three radiolarian species and subspecies, among which, six new species, one new subspecies and 36 unidentified species, are included in the investigation. The 6 new species and 1 new subspecies are Triassocampe goricani, Triassocampe dumitricai, Triassocampe coronata inflata, Triassocampe relica, Archaeospongoprunum muyinense. Neopaurinella deweveri and Neopaurinella kozuri . Based on morphological comparison and stratigraphical range, some possible evolutionary relations are suggested. Four radiolarian zones, namely, Triassocampe deweveri Zone (late Anisian), Triassocampe coronata coronata Zone (middle Anisian), Triassocampe coronata inflata Zone (middle Anisian), and Triassocampe dumitricai Zone (early Anisian) are established. The Early Triassic radiolarian fauna in this area has a very low diversity and mainly consists of survivors of the Permian radiolarians. The recovery of the Triassic radiolarian fauna takes place in early Anisian. In this period, the multicyrtid nassellarians are moderately diverse and characterized by having a slender shell with weak constriction among segments: the spumellarian species are characterized by having needle-like main spines. In the middle and late Anisian, the shells of the multicyrtid nassellarians became strong with developed constrictions between segments, and both the spumellarians with needle-like spines and the spumellarians with three-bladed spines are diverse.

Site 1172 is located in a water depth of ~2620 m on the flat western side of the East Tasman Plateau (ETP), ~170 km southeast of Tasmania. At 44°S, the site lies in cool subtropical waters just north of the Subtropical Front in an area where both the Subtropical Front and the East Australian Current have had variable influence through time. The primary objectives of coring and logging at Site 1172 were to obtain in the far southwest Pacific (1) an Oligocene to Holocene pelagic carbonate section under long-term influence of the East Australian Current to construct moderate to highresolution paleoceanographic and biostratigraphic records, (2) an Eocene siliciclastic sediment sequence for better understanding of paleoceanographic and paleoclimatic conditions before Antarctic Circumpolar Current development, and (3) an Eocene-Oligocene transitional sequence to determine the effects of the initial opening of the Tasmanian Gateway on the paleoceanography of the Pacific Tasmanian margin and to compare and contrast (4) changing paleoenvironmental and paleoceanographic conditions on each side of Tasmania as the Tasmanian Seaway opened and the Antarctic Circumpolar Current developed. This site was also expected to provide valuable information about the tectonic history of the ETP, including evolution of an inferred volcanic hot spot in the Eocene.

FERRIERE, J., BONNEAU, M., CARIDROIT, M., et al. 2001. Les nappes tertiaires du Paikon (zone du Vardar, Macedoine, Grece); arguments stratigraphiques pour une nouvelle interpretation structurale. Comptes Rendus de l'Academie des Sciences, Serie II. Sciences de la Terre et des Planetes 332 (11), 695-702.

F ENG , Q., ZHANG , Z., GU , S. & YE , M. 2001a. Radiolarian fauna from the Permian-Triassic transition in southwestern China. Dizhi Keji Qingbao = Geological Science and Technology Information 20 (3), 31-34.

Several interpretations concerning the structures of the Paikon mountains (Greece) have been proposed. Our new results (Upper Jurassic to Lower Cretaceous Radiolaria, Jurassic Gastropoda...), some of them from metamorphic series (Ellipsactinies and Rudistes in the Lower Unit), give new constraints to build the palaeogeography and the tectonic history. These data permitted to define new series (e.g., the Lakka series) and reconstruct most of the others (e.g., the series of the lower units). Their palaeogeographic similarities are detailed and a new hierarchy of the tectonic contacts is settled (fundamental tectonic contacts or simple disharmonic structures). In that way, it appears that the Gola Tchouka window is the main one in the Paikon massive (Tertiary nappes) under another major unit (Elefterochori unit), which i s simply buckled by secondary faults.

The aim of this article is to present the recent research development about the radiolarian faunas during the PermianTriassic transition. Over 90% of the late Changxingian radiolarian species disappeared at the end-Permian and only a few species that could be found in both shallow limestones and pelagic cherts survived successfully into the Triassic. The survival period spans Griesbachian to Smithian and the recovery period, Spathian, and Radiolaria began to radiate from Anisian stage. The radiation of the Middle Triassic radiolarians was intensively controlled by anoxia event.

FENG, Q. L., GU, S. Z. & DING, M. H. 2001b. Early Triassic Radiolarians from Sangzhi, Hunnan. Acta Micropaleontologica Sinica 18 (3), 249-253.

G A S T , R. J. & CA R O N , D. A. 2001. Photosymbiotic associations in planktonic foraminifera and radiolaria. Hydrobiologia 461, 1-7.

F ENG , Q. L., SHEN , S. Y., LIU , B. P., et al. 2002. Permian radiolarians, chert and basalt from the Daxinshan Formation in Lancangjiang belt of southwestern Yunnan, China. Science in China Series D-Earth Sciences 4 5 (1), 63-71.

Foraminifera, radiolaria and acantharia are relatively large (> 1 mm in most cases) unicellular eukaryotes that occur in pelagic oceanic communities. Commonly referred to as planktonic sarcodines, these organisms often harbor algal symbionts. The symbionts have been described as dinoflagellates, chrysophytes and prasinophytes based upon their morphology either in the host or as free-living organisms in culture. To investigate the molecular taxonomic affiliations of the algae, and to determine the sequence variability between symbionts from individual hosts, we examined the small subunit ribosomal DNA sequences from symbionts isolated from planktonic foraminifera and radiolaria. The symbionts that we analyzed included dinoflagellates, prasinophytes and prymnesiophytes. We have,

The stratigraphical sequences composed of chert and basalt were found in the Daxinshan area of Simao and the Manbie area of Jinghong, southwestern Yunnan. The Middle Permian to ealiest Late Permian radiolarians, such as Follicucullus and Pseudoalbaillella, have been identified from the chert. The chert from the Manbie area of Jinghong is characterized by high SiO2 content (over 92%), large ratios of MnO/TiO2 (2.15) and low ratios of Al/(Al+Fe+Mn) (less than or equal to0.1) and Ce/Ce*(0.4), which indicate that the chert was deposited in pelagic basin. The chert from the Daxinshan area

14

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Bibliography - 2001-2002

through our studies of planktonic sarcodine symbioses, and through comparison with other symbiotic associations (corals and lichens), observed that taxonomically distinct lineages of symbiotic algae are not uncommon. How do such different algae share the function of symbiosis, while other, more related algae, do not? We propose that there are commonalties that exist between symbiotic algae that confer symbiotic 'competence', and the way to begin the search for these is to utilize the different algal symbiont lineages.

with over 45 species disappearing in the topmost 1.5 m. Above this level, the fauna is entirely changed. Lower Hettangian beds contain a low diversity fauna composed of simple spumellarians with irregular meshwork and primitive rod-like spines; nassellarians are comparatively rare and unusually small. These radiolarians are assigned to the lower Hettangian Canoptum merum Zone, which i s equivalent to the North American Psilocerras assemblage of the ammonoid standard zonal sequence. Less than twenty genera survive the T-J boundary in Queen Charlotte Islands but not all are present in the lower Hettangian. About half continue to radiate in the Lower Jurassic and beyond, while others are rare and soon disappear. Only about 10 species survive the boundary and nearly all die out in the Hettangian. The faunal sequence at Kennecott Point is similar to Kunga Island, but scarcity of well preserved faunas in tuffaceous boundary beds makes the numbers less striking. Eleven new genera appear in the lower Hettangian and about 30 species gradually accrue from these and other surviving genera; there are no extinctions. Several more genera appear in the middle and upper Hettangian and species diversity gradually rises. Nassellarian diversity increases dramatically in the Sinemurian (especially among multicyrtids), with 65 species recorded by the end of the stage. Throughout this time analogous morphological changes are recognized in the spumellarian population: meshwork becomes more regular, and the simple rod-like spines give way to the more advanced tri-radiate type. The pattern of extinction and recovery seen in radiolarians from Queen Charlotte Islands parallels trends seen in T-J boundary faunas from Japan. This suggests that the end-Triassic microplankton extinction may have been worldwide in extent, a factor likely to affect other groups higher in the food chain.

GRANT-MACKIE, J. A., AITA, Y., BALME, B. E., et al. 2000. Jurassic palaeobiogeography of Australia. Memoir of the Association of Australasian Palaeontologists 23, 311-354. G U E X , J. 2001. Increasing involution and Cope's rule. Bulletin de la Societe Vaudoise des Sciences Naturelles 8 7 (4), 373-379. In this paper, we demonstrate that Cope's rule merely describes the particular case where volume increase is strictly coupled with the linear dimension of the organisms. Allometries which are frequently observed in the evolution of the organisms' morphology mean that their size, volume and surface can vary independently. The consequences of this can be summarized as follows. Volume increase not coupled with an increase of the linear dimension of the organisms generates increasing involution and/or elongation in shelly cephalopods, forams and radiolarians. Increasing of the biomineralizing surface not coupled with volume increase generates increasing complexity in the sutures and growth lines in ammonites and an increase in the complexity and number of chambers in forams.

H A L A M I C , J., MA R C H I G , V. & G O R I C A N , S. 2001. Geochemistry of Triassic radiolarian cherts in NorthWestern Croatia. Geologica Carpathica 52 (6), 327-342.

H A D A , S., IS H I I , K. I ., L ANDIS , C. A., et al. 2001. Kurosegawa Terrane in Southwest Japan; disrupted remnants of a Gondwana-derived terrane. In: (HADA, S., YOSHIDA, M., et al. eds). Crustal evolution in South and Southeast Asia. Gondwana Research. 4/1: 27-38

The analysed Triassic (Illyrian, Lower Fassanian, Upper Carnian) radiolarian cherts on Zumberak, Ivanscica, Kalnik and Medvednica Mts (NW Croatia) are rocks with high SiO2 content (mean >90 %) and the major part of silica is of biogenic origin. Besides this siliceous component, two others stand out in the radiolarian cherts. One of them is detritic (terrigenous input) and it consists mainly of Al, Ti, K, Zr, Hf, Cr, Th, Rb, Nb and Sc. The other, hydrothermal one, is composed of Fe, Mn, P, Cu, Pb, Zn, Ni, Co and Sr. The terrigenous component is a significant REE carrier. The radiolarian cherts on Kalnik and Medvednica Mts show a positive Ce-anomaly (Ce/Ce*) which indicates a sedimentation in a narrow trough relatively close to the continent. The negative Ce-anomaly on Zumberak and Ivanscica Mts suggests a reduced terrigenous input. The radiolarian cherts in the last mentioned areas are sedimented directly onto the dolomites and limestones of the carbonate platform. This means that the terrigenous input was probably weaker, because of the width of the disintegrated carbonate platform (larger distance to the continent) or because of a topographically higher position (bypass of fine terrigenous material) with respect to Medvednica and Kalnik.

The Kurosegawa Terrane is an anomalous, disrupted, Paleozoic and Mesozoic lithotectonic assemblage characterized by fragments of continent and continental margins. It is located in Southwest Japan where it lies between two Mesozoic subduction complex terranes. The Kurosegawa Terrane is an exotic and far-travelled geologic entity with respect to its present position. Limestones of the Kurosegawa Terrane formed along a continental margin yield fusulinacean fossils Cancellina, Colania and Lepidolina. Accordingly, the Kurosegawa Terrane was once situated within the ColaniaLepidolina territory in the East Tethys-Panthalassa region at a palaeo-equatorial latitude, possibly close to the eastern margin of the South China and/or Indochina-East Malaya continental blocks. These blocks had rifted from Gondwana by late Devonian. They drifted northwards, passing through the Colania-Lepidolina territory in mid-Permian time, and amalgamated with the proto-Asian continent during the late Triassic. Subsequently, during the Cretaceous, parts of the allochthonous continental blocks and their associated tectonic collage were transpressed, dispersed, and displaced from the southeastern periphery of Asia towards the north. As a result, the Kurosegawa Terrane is formed as a disrupted allochthonous terrane, characterized by a serpentinite melange zone, lying between the adjoining Mesozoic subduction complex terranes.

HAMILTON, N. & PUDSEY, C. J. 2001. Magnetic properties of upper Quaternary sediments from the Scotia Sea, Antarctica. Antarctic Science 13 (1), 61-66. Magnetic properties of bulk sediment samples taken from three cores from the Scotia Sea, Antarctica were determined using a fullyautomated variable field traslation balance. Fine-grained detrital magnetite is identified as the principal carrier of remanence in these Upper Quaternary sediments which were deposited under the influence of the Antarctic Circumpolar Current. Inferred magnetite grain-size is consistent with published bulk grain-size data for these cores. Pseudo-single domain grains characterize Holocene camples, and larger, multi-domain grains occur in glacial samples from two of the cores, whereas samples from the northernmost core site show dominantly multi-domain behaviour.

HAGGART, J. W., CARTER, E. S., BEATTIE, M. J., et al. 2001. Stratigraphy of Triassic/Jurassic Boundary Strata, Queen Charlotte Islands, British Columbia: Potential Global System Stratotype Boundary IGCP SW England Workshop Abstracts (eds). p. 10-13. IGCP SW England Workshop, 1317 October. The mass extinction and recovery of radiolarians at the T-J boundary is documented in thick, continuous sections at two localities in Queen Charlotte Islands: Kunga Island and Kennecott Point. Radiolarians are abundant throughout both sequences; accessory faunas include conodonts, and rare ammonites of late Rhaetian and early Hettangian age. The Rhaetian radiolarian fauna is rich and diverse, composed largely of spumellarian and nassellarian genera originating in the late Carnian and Norian. Many distinctive new species arise in the Rhaetian even in the upper beds. Over 65 described species are present at the base of the Globolaxtorum tozeri Zone (the topmost radiolarian zone of the Triassic) on Kunga Island. The abrupt disappearance of this fauna takes place over an interval of ~5 m

H A S L E T T , S. K. 2002. Quaternary Environmental Micropalaeontology. Arnold, London, 288 p. HIRAYAMA, R. & SKURAI, K. 2001. An unusual land turtle of family Nanhsiungchelyidae (superfamily Trionychoidea, order Testudines) from the Upper Cretaceous of Hokkaido, North Japan. In: (A NONYMOUS eds). Abstracts of papers; Sixty-first annual meeting, Society of Vertebrate 15

Bibliography - 2001-2002

Radiolaria 20 Russia) to permit the establishment of a single radiolarian zonation for the Northwest Pacific. The new zonation consists of six Late Cretaceous and two Paleocene interval zones: Theocampe urna zone (Tu, Coniacian), Dictyomitra koslovae zone (Dk, Santonian to early Campanian), Amphipyndax tylotus zone (At, late Campanian), Pseudotheocampe abschnitta zone (Pa, early Maastrichtian), Clathrocyclas gravis zone (Cg, mid Maastrichtian), Lithostrobus wero zone (Lw, early Paleocene), Buryella foremanae zone (Bf, mid Paleocene). Zone Dk may be subdivided into Santonian and early Campanian subzones based on the first appearances of Archaeospongoprunum hueyi gr., n.gr., Protoxiphotractis perplexus and Lithocampe wharanui. Previous workers’ recognition of an Amphipyndax pseudoconulus or A. enesseffi assemblage in Japan is found to be erroneous. Careful examination of illustrations of the A. pseudoconulus-tylotus complex reveals that A. pseudoconulus s.s. (= A. enesseffi of Foreman 1966) is very rare in Japan and restricted to the late Campanian, its first appearance coinciding with that of A. tylotus.

Paleontology. 62. University of Oklahoma. Norman, OK, United States. 2001. HIRSCH, F. & ISHIDA, K. 2001. The Izanami Plateau; Japan's pre-accretionary Permo-Triassic low latitude pelagic carbonates. In: (G VIRTZMAN , Z. & AMIT , R. eds). Annual Meeting Israel Geological Society. 2001: 6 1 . Israel Geological Society. Jerusalem, Israel. 2001. HISADA, K. I., LEE, Y. I., KAMATA, Y. & SHIZUKA, T. 2001. Gyeongsang Supergroup, Korea; Consideration on the connecting points with the Japanese Islands. In: (M ATSUOKA, A. eds) Paleoceanography of the PanthalassaTethys Invitation to Global Field Science Topics i n Paleontology 2. Paleontological Society of Japan, 73-86.

HOLLIS, C. J., RODGERS, K. A. & STRONG, C. P. 2000b. New Zealand perspective on global change from late Cretaceous to early Eocene: (b) the Cretaceous-Tertiary transition at Flaxbourne River, eastern Marlborough. GFF 122, 73-74.

H O L L I S , C. J. 2000. Radiolarians: their potential for reconstructing prehistoric oceanography (eds). p. Species 2000: New Zealand millennial symposium: a review and inventory of New Zealand's biodiversity, Museum of New Zealand, Te Papa Tongarewa, Wellington , 1-5 February 2000.

IEDA , K. 2001. Radiolarians from the Chichibu Terrane i n western part of Hamamatsu City, Shizuoka Prefecture, Japan. Toyohashishi Shizenshi Hakubutsukan Kenkyu Hokoku = Science Report of the Toyohashi Museum o f Natural History 11, 23-26.

H O L L I S , C. J. in press. Biostratigraphy and paleoceanographic significance of Paleocene radiolarians from offshore eastern New Zealand. Marine Micropaleontology.

JANNOU , G. E. & OLIVERO, E. 2001. Record of Paleogene radiolarians from Tierra del Fuego Island, Argentina. Ameghiniana 38 (3), 317-320.

A 100 m-thick Paleocene sequence of mainly pelagic sediments at ODP Site 1121, on the eastern flanks of the Campbell Plateau, contains few to common radiolarians of relatively low diversity in the lower 40 m (Early to early Late Paleocene) and abundant, diverse radiolarian assemblages in the upper 60 m (mid-Late Paleocene). The 150 taxa recorded from the entire Paleocene interval are thought to under-represent the actual species diversity by at least one half as many morphotypes have not been differentiated below the level of genus. Assemblages in the lower 40 m are similar to those described from onland New Zealand and DSDP Site 208 (northern Lord Howe Rise); they are correlated with South Pacific radiolarian zones RP4 and RP5. Assemblages in the upper 60 m differ from other known Late Paleocene assemblages in the great abundance of plagiacanthids and cycladophorids. Similarities are noted with later Cenozoic cool-water assemblages. This upper interval is correlated with South Pacific zone RP6, as revised herein, based on comparison with faunas from Site 208 and Marlborough, New Zealand. The interval is also correlated with the upper part of North Atlantic zone RP6 (RP6b-c) based on the presence of Aspis velutochlamydosaurus, Plectodiscus circularis and Pterocodon poculum. Other species, such as Buryella tetradica and B. pentadica, are valuable for local correlation but exhibit considerable diachroneity between the Pacific, Indian and Atlantic Oceans. An age model for the Paleocene interval at Site 1121, based on well-constrained nannofossil and radiolarian datums, indicates that the rate of compacted sediment accumulation doubles from 15 to 30 mm/ka at the RP5/RP6 zonal boundary. In large part, this is due to a sudden and pronounced increase in accumulation rates for all siliceous fossils; radiolarians and larger diatoms increase from 10,000 specimens/cm2/ka. This apparent increase in biosiliceous productivity is age-equivalent to a mid-Paleocene cooling event (57-59 Ma) identified from global stable isotope records that is associated with the heaviest 1 3C values for the entire Cenozoic – heavy values imply enhanced oceanic productivity.

The finding of two assemblages of well preserved radiolarians, one from Punta Gruesa and the other from Cabo Irigoyen-Arroyo Vasco area, on the Atlantic coast, Tierra del Fuego Island, is reported. The former contains: Amphicraspedum sp. cf. A. murrayanum Haeckel, Buryella dumitricai (Petrushevskaya), Orbiculiforma renillaeformis (Campbell and Clark), and Corythomelissa adunca (Sanfilippo and Riedel) among the most representative species, its age i s constrained to Late Paleocene-Early Eocene. The latter assemblage contains T h e o c o t y l e (Theocotylissa) f i c u s (Ehrenberg), Amphisphaera macrosphaera (Nishimura), Buryella tetradica Foreman, and Spongurus bilobatus Clark and Campbell, its age i s Early Eocene in agreement with the associated planktonic foraminifera. Both assemblages contain Heliostylus sp., Mita sp., and Stylosphaera minor Clark and Campbell.

JIANXIN, Y., AKIRA, Y. & KIYOKO, K. 2001. Upper Permian biostratigraphic correlation between conodont and radiolarian zones in the Tamba-Mino Terrane, Southwest Japan. Journal of Geosciences, Osaka City University 44, 97-119. Some important Permian conodonts were found in the bedded cherts of the Gujo-hachiman and the Ryozen sections in the Tamba-Mino Terrane, Southwest Japan. On the basis of the biohorizons of characteristics conodont and radiolarian species, six conodont interval zones are recognized in the Upper Permian, where four radiolarian assemblage zones are settled. The conodont interval zones include the Clarkina liangshanensis Interval Zone, the Clarkina orientalis Interval Zone, the Clarkina subcarinata Interval Zone, the Clarkina parasubcarinata Interval Zone, the Clarkina postwangi Interval Zone and the Clarkina meishanensis zhangi Interval Zone, in ascending order. The radiolarian assemblage zones are the Follicucullus scholasticus-Follicucullus ventricosus Assemblage Zone, the Follicucullus charveti- Albaillella yamakitai Assemblage zone, the Neoalbaillella ornithoformis Assemblage Zone and the Neoalbaillella optima Assemblage Zone, in ascending order. Both conodont and radiolarian biostratigraphic data have been correlated with each other, and the Upper Permian biostratigraphic zonations have been examined in relation to those in South China. Changes of conodont and radiolarian faunas are discussed. A new species of Clarkina is described from the Upper Permian cherts.

HOLLIS, C. J., FIELD, B. D., JONES, C. M., et al. 2000a. New Zealand perspective on global change from late Cretaceous to early Eocene : (a) the Paleocene-Eocene transition at Mead Stream, Marlborough. GFF 122, 71-72. HOLLIS, C. J. & KIMURA, K. 2001. A Unified Radiolarian Zonation for the Late Cretaceous and Paleocene of Japan. Micropaleontology 47 (3), 235-255. Previous radiolarian zonations for the Late Cretaceous and Paleocene of Japan are reviewed in terms of species identifications and age determinations. With adoption of a consistent identification scheme, a remarkably uniform succession of radiolarian assemblages is evident throughout Southwest Japan. Sufficient species range into higher northern latitudes (Hokkaido, eastern

J IN , X., XIE, G. & WANG , Y. 2001. Some stratigraphic and sedimentologic constraints on the features of the Changning-Menglian Tethys, Yunnan, China. In: (H ADA , S., YOSHIDA, M., et al. eds). Crustal evolution in South and Southeast Asia. Gondwana Research. 4; 1, Pages 55-60 16

Radiolaria 20

Bibliography - 2001-2002 offer a possibility for a broad correlation of late Albian–Cenomanian deposits of the Greater Caucasus, Crimea, Russian platform, and Mediterranean region. Late Albian radiolarians of the Greater Caucasus are pictured under scanning microscope for the first time.

International Association for Gondwana Research. Osaka, Japan. 2001. The interpretation of the (Lower Carboniferous) basalt- (Middle Carboniferous to Middle Permian) carbonate succession in the central zone of the Changning-Menglian Belt in western Yunnan, China as a seamount is one of the major arguments supporting a large ocean model of the Changning-Menglian Tethys. Our field investigations and laboratory work lead to the conclusion that the basalt-carbonate succession of the Changning-Menglian Belt is not genetically related to seamount. It is a normal lithological succession that developed on continental crust, and it is underlain and overlain by marine carbonate and/or clastic deposits.

KEMKIN, I. V. & FILIPPOV, A. N. 2001. Structure and genesis of the lower structural unit of the Samarka Jurassic accretionary prism (Sikhote-Alin, Russia). Geodiversitas 23 (3), 323-339. Based on a study of several cherty-terrigenous sequences of the Samarka terrane in Sikhote-Alin, comprising lithologic and paleontological analysis, the different age of the transitional layers from marine formations to paleocontinental-margin deposits was established and the succession of marine fragments accretion was restored. The obtained data shows that low structural level of the Samarka accretionary prism is composed of a minimum of four successive tectonostratigraphic units that differ both in age of accreted marine fragments and time of their accretion. Each unit consists of deposits of a paleo-oceanic plates gradually changing above on a section by terrigenous rocks, which further are replaced by an olistostrome. The relatively young pelagic rocks and overlapping terrigenous deposits occur structurally below older deposits. Such structure of the Samarka prism results from a consecutive accretion of the fragments of a different-age sites of a paleo-ocean plate. Radiolarian age data for the accretionary prism indicates that fragments of a Late Permian-Triassic, Early TriassicEarly Jurassic and Early Triassic-Middle Jurassic paleo-oceanic plate were consecutively accreted into the prism.

K A K U W A , Y. & XIA , W. C. 2001. Studies on the Late Paleozoic mass extinction events and radiolaria-bearing siliceous rocks in South China. In: (M ATSUOKA , A. eds). Paleoceanography of the Panthalassa-Tethys Invitation t o Global Field Science Topics in Paleontology 2 . 53-64. Paleontological Society of Japan. K AMATA, Y., SASHIDA, K., UENO, K., et al. 2002. Triassic radiolarian faunas from the Mae Sariang area, northern Thailand and their paleogeographic significane. Journal of Asian Earth Sciences 20 (5), 491-506. Early to Late Triassic (Spathian to Carman) radiolarians were obtained from the bedded chert sequence of the Mae Sariang Group distributed in northern Thailand. Based on the similarity of radiolarian fauna and petrographical characteristics, it is inferred that the fine-grained siliceous and calcareous sediments of the Mae Sariang Group are equivalent to those belonging to the eastern marginal facies of the Sibumasu Block. Moreover, the occurrence of an early (?) Carman radiolarian assemblage from bedded chert shows that the closure of the Paleotethys Ocean between the Sibumasu and Indochina Blocks in northern Thailand occurred after the early Carman.

KIDDER, D. L. 2001. Secular distribution of biogenic silica through the Phanerozoic; comparison of silica-replaced fossils and bedded cherts at the series level. Journal o f Geology 109 (4), 509-522. The modern marine silica cycle is dominated by silica-secreting phytoplankton, principally diatoms, but this cycle has evolved considerably during the Phanerozoic. We analyzed the temporal distribution of silica-replaced fossils and bedded chert to determine the influence of factors such as extinctions and climate change on siliceous facies. Trends in silica replacement of fossils match faunal radiations during the Ordovician and Siluro-Devonian, with peaks in silica replacement in the Late Ordovician and Middle Devonian corresponding to peaks in the abundance and diversity of siliceous sponges. Sharp drops in the abundance of silica-replaced fossils and/or bedded cherts coincide with four of the five major mass extinctions. No discernible decrease marks the extinction at the end of the Triassic. We expected peaks in bedded chert deposition during glacial episodes because enhanced ocean circulation should favor more and stronger upwelling. Orogenic episodes, which may trigger continental glaciation, may also increase silica supply and further enhance siliceous deposition during these intervals. The data we have sampled provide mixed results. The Late Ordovician and Late Devonian glaciations do not correspond to peaks in bedded chert abundance, although the increase in bedded cherts relative to silica-replaced fossils during the Carboniferous may reflect a climatic influence. The well-known Middle Miocene circum-Pacific chert event does correspond with a glacial interval. Lows in silica deposition should mark intervals when the ocean was stratified and/or ocean circulation was sluggish. Data from the mid-Cretaceous and Early Triassic appear consistent with this expectation. Following the shift to a diatom-dominated silica cycle in the Late Jurassic and Cretaceous, patterns of chert abundance through time became more volatile and more responsive to external influences on marine silica burial such as icehouse and greenhouse effects. Prior to the diatom radiation, biogenic silica burial was probably more equitably divided between radiolarians and siliceous sponges. This more cosmopolitan control of silica burial may have dampened the effects of climatic factors on silica accumulation, though better resolved data are needed to test this possibility.

K ANFOUSH , S. L., HODELL , D. A., CHARLES , C. D., et al. 2002. Comparison of ice-rafted debris and physical properties in ODP Site 1094 (South Atlantic) with the Vostok ice core over the last four climatic cycles. Palaeogeography Palaeoclimatology Palaeoecology 1 8 2 (3-4), 329-349. Visual counts of ice-grafted debris (IRD), foraminifera, and radiolaria were made for similar to1500 samples in Site 1094 spanning the last four climatic cycles (marine isotope stages 111). Most, but not all, of the IRD variability is captured by wholecore physical properties including magnetic susceptibility and gamma-ray attenuation bulk density. Glacial periods are marked by high IRD abundance and millennial-scale variability, which may reflect instability of ice shelves in the Weddell Sea region. Each interglacial period exhibits low IRD and high foraminiferal abundance during the early part of the interglacial, indicating relatively warm sea-surface temperatures and reduced influence of sea ice. IRD increases and foraminiferal abundances decrease during the latter part of each interglacial, indicating a return to more glacial-like conditions. Glacial terminations I and V are each characterized by a step-wise reduction in ice-rafting punctuated by a brief pulse in IRD delivery and reversal in ∂1 8O. The coarse fraction of the sediment i s dominated by ash and radiolaria, and the relative abundance of these components is remarkably similar to the concentration of Na+ in Vostok. Each of these variables is believed to be controlled mainly by sea-ice cover, thereby providing a means for sediment-ice core correlation.

K AZINTSOVA , L. I. 2002. Correlation of Albian Radiolarian Assemblages from the Greater Caucasus, Europe, and Mediterranean. Stratigraphy and Geological Correlation 1 0 (1), 69-76.

K OJIMA , S., YAMAKITA , S., OTOH , S. & EHIRO , M. 2001. Paleozoic-Mesozoic rocks in Sikhote-Alin, Russia: Geology of East Asia before opening of the Sea of Japan. In: (MA T S U O K A , A. eds) Paleoceanography of the Panthalassa-Tethys Invitation to Global Field Science Topics in Paleontology 2 . Paleontological Society of Japan, 87-94.

Generalized data on Albian radiolarians from the Greater Caucasus refine composition of their Spongostichomitra elatica (middle Albian) and Dictyomitra disparlita–Crolanium triangulare (upper Albian) assemblages. The assemblages are correlated with coeval (or close in age) radiolarian faunas of the Crimea, Russian platform, Poland, Czechoslovakia, Romania, Yugoslavia, Italy, Spain, and Tunisia. The correlation revealed many species in common. These species suggest that above regional basins were interconnected and

17

Bibliography - 2001-2002

Radiolaria 20 Two types of manganese nodules were observed in the Peru Basin: large botryoidal nodules in basins and small ellipsoidal nodules on slope positions. The sediment in areas with large botryoidal nodules contains a thinner and weaker oxidation zone than the sediment under small ellipsoidal nodules, indicating that diagenetic processes in the sediment, which supply manganese nodules with metals for their growth, are stronger in sediments on which large botryoidal nodules grow. Organic matter, which activates remobilization of metals, occurs mostly in the form of refractory lipidic compounds in the inner capsule of radiolaria. This material needs bacterial degradation to act as a reducing agent. Easily oxidizable organic components could not be found in the sediments. Other changes in sediment composition do not have a link to manganese nodule growth. Biogenous components (radiolarians, organogenic barite and apatite) increase towards the equatorial high-productivity zone. Authigenous clay minerals (nontronite as well as montmorillonite with high Fe+ 3 incorporation on positions of ochtaedral Al) increase with distance from the continent. The assessment of environmental impacts will have to take into account the regional differences in sediment composition and the small-scale variability of manganese nodules.

K OZUR , H. W. & REPETSKI , J. E. 2002. Paulanoblella, nomen novum (Radiolaria) replaces N o b l e l l a Kozur, Mostler & Repetski, 1996, a homonym of Noblella Barbour, 1930 (Amphibia). Journal of Micropalaeontology 21, 28-28. L I U , J. B. & AI T C H I S O N , J. C. 2002. Upper Paleocene radiolarians from the Yamdrok melange, south Xizang (Tibet), China. Micropaleontology 48, 145-154. A rich assemblage of upper Paleocene radiolarians has been extracted from siliceous mudstones that locally form the matrix of the Yamdrok melange in southern Tibet. Faunas include Bekoma campechensis, Lychnocanoma? costata, Orbula comitata, Orbula ducalis, Clathrocycloma parcum, Amphisphaera macrosphaera, Phormocyrtis turgida, Spongurus? regularis, and Dictyocephalus middouri, and correspond to the Bekoma campechensis Zone. This i s the first discovery of upper Paleocene radiolarians from Tibet and provides a maximum age constraint on the timing of formation of the Yamdrok melange, a unit postulated to have developed during collision of the northern margin of India with an intra-oceanic island arc system within Tethys.

M A T S U O K A , A., KO B A Y A S H I , K., NA G A H A S H I , T., et al. 2001a. Early Middle Jurassic (Aalenian) radiolarian fauna from the Xialu chert in the Yarlung Zangbo Suture Zone, southern Tibet. In: (M ETCALFE , I., SMITH, J. M. B., et al. eds). Faunal and Floral Migrations and Evolution in SE Asia-Australasia. 105-110. A.A. Balkeema Publishers, Lisse.

LUCIANI, V., COBIANCHI, M. & JENKYNS, H. C. 2001. Biotic and geochemical response to anoxic events; the Aptian pelagic succession of the Gargano Promontory (southern Italy). Geological Magazine 138 (3), 277-298. Microfossil distribution patterns and high-resolution ∂ 1 3C and ∂ 1 8O curves, calibrated against planktonic foraminiferal and calcareous nannofossil data, are provided for the Aptian pelagic Coppitella section of the Gargano Promontory (southern Italy). The succession consists of cyclically arranged couplets of bioturbated grey marlstones and off-white marly limestones, referable to the Marne a Fucoidi. In the lower portion of the section, two thin black shales were recognized. The high-resolution ∂1 3C curve presented here correlates with those of other Alpine–Tethyan sections, albeit with lower absolute values. The onset of deposition of organic-rich sediments falls at the top of the interval of unchanging carbonisotope values, whereas the upper black shale is documented from the interval of the main Aptian positive ∂1 3C excursion. According to our biostratigraphic data, the deposition of organic matter in the Gargano Promontory persisted through Early/Late Aptian boundary time. Using a chemostratigraphic definition, only the lower black shale is referred to the Selli Level. As far as the biotic response i s concerned, the onset of the ‘nannoconid crisis’ is recorded considerably below the lower black shale, whereas the ‘Globigerinelloides eclipse’ is recorded below and within the upper black shale. The distribution of meso-eutrophic indices (Zygodiscus spp., radiolaria) vs. moderate-fertility indices (Rhagodiscus asper and Lithraphidites carniolensis) testifies to a modest increase of surface-water fertility only throughout the stratigraphically higher black shale. The occurrence of a benthic foraminiferal fauna, albeit impoverished, in both the basal and upper black horizons clearly documents dysaerobic rather than completely anoxic conditions on the sea floor. Relative sea-level rise at the time of the Selli Event in the Gargano Promontory is documented by drowning and foundering of the Apulia platform margin, situated adjacent to the basin in which the Marne a Fucoidi accumulated.

M ATSUOKA , A., YANG , Q., KOBAYASHI , K., et al. 2001b. Siliceous deposits in the Yarlung-Zangbo Suture Zone, southern Tibet, China: Paleoceanography in the east Tethys. In: (M ATSUOKA , A. eds). Paleoceanography of the Panthalassa-Tethys Invitation to Global Field Science Topics in Paleontology 2 . 39-44. Paleontological Society of Japan. M A T S U O K A , A. & ZA M O R A S , L. R. 2001. Jurassic accretionary complex in the North Palawan Block, Philippines: Southwestern extension of Jurassic accretionary complex in Japan. In: (MATSUOKA, A. eds) Paleoceanography of the Panthalassa-Tethys Invitation t o Global Field Science Topics in Paleontology 2 . Paleontological Society of Japan, 31-38. M ATUL, A. G., YUSHINA, I. G. & EMELYANOV, E. M. 2002. On the Late Quaternary paleohydrological parameters of the Labrador Sea based on radiolarians. Oceanology 4 2 (2), 247-251. Radiolarian assemblages are studied in the sediments of core P-172 from the central part of the Labrador Sea. The paleosalinity and paleotemperature for the whole Late Quaternary interval were reconstructed using factor analysis and spline interpolation of the data on the radiolarian distribution. Paleoceanographic information was obtained for the entire interval of the Late Quaternary period. During the last interglacial (oxygen isotopic stage 5), warm and saline North Atlantic water masses, whose sea surface temperature exceeded the present-day values by 4-5°C and sea surface salinity exceeded the present-day values by 0.5-1.0 parts per thousand, penetrated into the central part of the Labrador Sea. Similar situations occurred repeatedly during the initial stages of the last glaciation development (from the final part of stage 5 until stage 3), although the temperature and salinity did not exceed the present-day level. The sharp Late Pleistocene salinity minima in the surface waters correlate in time with Heinrich events H6, H5, H4, and H1/H2, which mark the penetration of enormous continental ice masses from the surrounding land into the North Atlantic.

L UO , H., AITCHISON, J. C. & WANG , Y. J. 2002. Devonian (upper Emsian lower Givetian) radiolarians from the Tanhe Formation, Nanning, Guangxi, southwest China. Micropaleontology 48, 113-127. A moderately well-preserved radiolarian fauna consisting of 20 Devonian (upper Emsian-lower Givetian) taxa was recovered from siliceous strata in the Wuxiangling section, Nanning, Guangxi, southwest China. This fauna is dominated by spumellarians, but also includes some distinctive ceratoikiscid forms that have potential for biostratigraphic studies and regional correlation. Six new species, Ceratoikiscum coroniferum n. sp., Stigmosphaerostylus cubicus n. sp., Trilonche nanningensis n. sp., Trilonche remosa n. sp., Trilonche tanheensis n. sp. and Trilonche xinpoensis n. sp., are described.

M C C ARTHY , A. J., JASIN, B. & HAILE, N. S. 2001. Middle Jurassic radiolarian chert, Indarung, Padang District, and its implications for the tectonic evolution of western Sumatra, Indonesia. Journal of Asian Earth Sciences 19 (1-2), 31-44.

MARCHIG, V., VON, S. U., HUFNAGEL, H. & DURN, G. 2001. Compositional changes of surface sediments and variability of manganese nodules in the Peru Basin. Deep Sea Research Part II: Topical Studies in Oceanography 48 (17-18), 35233547.

Radiolaria from chert in the Indarung Area belong to the Transhsuum hisuikyoense Zone, indicating an Aalenian, lower Middle Jurassic, age. Carbonate in the area has been dated as Upper Jurassic to Lower Cretaceous from the occurrence of Lovcenipora, and overlying tuff has given a radiometric K/Ar age of 105+ or -3

18

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Bibliography - 2001-2002

(Albian, uppermost Lower Cretaceous). The chert and carbonate are probably in tectonic contact, with the chert faulted into the limestone during ENE-directed compression. This comprises one of the best dated occurrences of allochthonous material in Sumatra and confirms the accretion of oceanic material along the Sunda margin during Mid- to Late-Cretaceous times.

NIMMERGUT, A. & ABELMANN, A. 2002. Spatial and seasonal changes of radiolarian standing stocks in the Sea of Okhotsk. Deep Sea Research Part I: Oceanographic Research Papers 49 (3), 463-493. The distribution of living radiolarians was investigated at 24 plankton stations collected with opening/closing nets from five depth intervals down to a depth of 1000m in combination with a hydrographic CTD survey in the Sea of Okhotsk during summer 1998 and spring 1999. The radiolarian standing stock varied seasonally and regionally from 10 to 1775 skeletons/m3 and was highest during summer. Nassellarians exhibited highest densities in summer, a period characterized by high productivity of heterotrophic organisms, whereas in spring, the season of maximum diatom production, phaeodarians dominated. Spumellarians were rare in both seasons. Regional differences in the radiolarian standing stocks were observed during both seasons. The radiolarian standing stock was highest during summer in the vicinity of the Sakhalin continental shelf, but pronounced regional variations in the radiolarian standing stock were also noted during spring. The seasonal and regional differences in the radiolarian standing stock are strongly related to the seasonally changing productivity regimes and the regional differences in the food availability. A total of 58 radiolarian taxa in spring and 64 taxa in summer were recorded. Of these eleven taxa and taxonomic groups (Antarctissa (?) sp. 1, Cycladophora davisiana, Challengeron sp. aff. C. neptuni, Peridium sp. 1, the Plagoniidae, Protocystis tridens, Dictyophimus hirundo, Rhizoplegma boreale, the Spongodiscidae, Ceratospyris borealis and Lophospyris sp. 1) made up an average of 89% of the spring and 80% of the summer assemblages. Most polycystine taxa inhabit confined depth intervals independent of their seasonally or regionally varying standing stock. A distinct depth relation of the polycystine radiolarian standing stock, specific radiolarian assemblages and taxa remains consistent during both seasons. The maximum polycystine radiolarian standing stock occurs generally at intermediate depth below the dichothermal layer. The depth habitat of specific radiolarian taxa and assemblages shows a close relationship with the Sea of Okhotsk water masses and allows definition of four assemblages: Surface water, subsurface cold water, intermediate water and deep water assemblage. This study shows that specific radiolarian taxa and assemblages are strongly related to water mass structure and to different water masses of the Sea of Okhotsk and thus represent a potential tool to reconstruct changes in water mass distribution and structure during the late Quaternary in the Sea of Okhotsk.

M I T S U G I , T., IS H I D A , K., W O O , B. G., et al. 2001. Radiolarian-bearing conglomerate from the Hayang Group, the Kyongsang Supergroup, Southeastern Korea. Journal o f Asian Earth Sciences 19 (6), 751-763. The non-marine Cretaceous Kyongsang Supergroup, which is divided into the Sindong, the Hayang and the Yuchon groups, is widely distributed in southeastern Korea. Radiolarian-bearing pebbles are collected from the conglomerates of the Kumidong and the Kisadong formations of the Hayang Group. The age of radiolarian fossils range from Late Permian to Middle Jurassic. In Korea, Permian to Middle Jurassic marine chert beds are not exposed. The directions of paleocurrents of the Kumidong and the Kisadong formations are mainly from the northeast to southwest. During Cretaceous time, the Mino-Tamba Belt, within which Permian to Middle Jurassic chert beds are exposed, is suggested to have been located northeast of the Kyongsang Basin. The radiolarian faunas of the Hayang Group are similar to those of the Mino-Tamba Belt and other associated Mesozoic accretionary belts in Japan (e.g. the Ashio Belt). The provenance of the radiolarian-bearing pebbles collected from the Kumidong and the Kisadong formations is interpreted to be the Mino-Tamba Belt and other associated Mesozoic accretionary belts in Japan.

MORIYAMA, Y. & WALLIS, S. 2002. Three-dimensional finite strain analysis in the high-grade part of the Sanbagawa Belt using deformed meta-conglomerate. Island Arc 1 1 (2), 111121. Regional ductile deformation of the Sanbagawa belt is generally thought to be characterized by constrictional strain, based on strain analysis using deformed radiolarians in the low-grade regions. Similar strain analysis could not be carried out in the medium- to high-grade zones, because it is very difficult to identify individual radiolarians after strong recrystallization. However, discovery of the first known meta-conglomerate in the high-grade region of the Sanbagawa Belt allows quantitative 3-D strain to be estimated in this region. Using a development of the Rf-phi method, an evaluation of appropriate errors for this estimate can be determined. The principal strain ratios and estimated errors are X/Y = 5.4-6.6 and Y/Z = 3.8-3.9 implying deformation in the flattening field and refuting the idea of uniform constrictional strain. Semi-quantitative markers of the shape of the strain ellipse throughout the high-grade regions suggest that the deformation of the Sanbagawa Belt i s dominantly in the flattening field. The difference with the earlier results may be due to late-stage overprinting by upright folding of the main ductile fabric in the low-grade region of western Shikoku.

N O B L E , P. J. & DANIELIAN, T. 2001. Status of work o n Ordovician radiolarian phylogeny and biodiversity. In: HOLROYD PATRICIA, A. (eds) IGCP 410; the Great Ordovician Biodiversification Event. PaleoBios. 21; 2, Suppl. 2. p. 8 . University of California, Riverside, United States. June 2224. NOBLE, P. J., LENZ, A. C., ZIMMERMAN, M. K. & HOLMDEN, C. 2001. Siliceous microfossil and geochemical events related to the lundgreni (graptolite) extinction, Early Silurian of the Canadian Arctic. In: (ANONYMOUS eds). Abstracts Geological Society of America, 2001 annual m e e t i n g . 15. Geological Society of America (GSA). Boulder, CO, United States. 2001.

Motoyama, I. & Ocean Drilling Program, L., Shipboard Scientific Party, College Station, Tx, United States,. 2002. Late Cenozoic radiolarians from South Atlantic Hole 1082A, Leg 175. In: (Berger Wolfgang, H., Wefer, G., et al. eds). Proceedings of the Ocean Drilling Program, scientific results, Benguela Current; covering Leg 175 of the cruises of the drilling vessel JOIDES Resolution; Las Palmas, Canary Islands, to Cape Town, South Africa; sites 10751087; 9 August-8 October 1997. Texas A&M University, Ocean Drilling Program. College Station, TX, United States.

Siliceous microfossil, graptolite, and geochemical data from measured sections in the Cape Phillips Formation, Canadian Arctic, provide a robust data set that allows for increased calibration of radiolarian faunal turnovers, radiation events, and recognition of paleoceanographically related changes during the early Wenlock through early Ludlow (Silurian). In particular, we recognize a sequence of events associated with a major and globally recognized extinction event in the graptolite community, the Lundgreni Event, which decimates the entire cyrtograptid lineage, and most of the monograptids and retiolitids. In the radiolarian community a major turnover corresponding to the first abundance of Inanigutta tarangulica group occurs within the early Homerian Cyrtograptus lundgreni-Testograptus testis Zone, prior to the Lundgreni Event. The I. tarangulica assemblage continues after the Lundgreni Event with no observed radiolarian extinctions. However; radiolarians occurring at the extinction horizon appear stressed, followed by a reduction in abundance that lasts until the end of the Wenlock. The Lundgreni Event is accompanied by both a geochemical and sedimentological signature. A +2.5 ∂ 1 3C org excursion occurs at the Lundgreni Event and is interpreted to be paleoceanographic in

Latest Miocene to Pleistocene poorly to well-preserved radiolarians were recovered from Hole 1082A in the Walvis Basin by Ocean Drilling Program Leg 175. Having moderate sedimentation rates and a good magnetostratigraphic record, this hole provides an excellent reference section for biochronology of the eastern South Atlantic Ocean. A set of radiolarian census data is given, and distinctive bioevents are identified and tied to the geomagnetic polarity time scale. This is the first attempt at a direct correlation of Neogene radiolarian bioevents with the geomagnetic polarity time scale in the South Atlantic off southwest Africa. Any one of the previously proposed zonal frameworks alone is hard to fully apply to radiolarian assemblages in Hole 1082A because of the rarity of the diagnostic species.

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Radiolaria 20

nature, as it is seen in two sections of differing lithofacies. Sedimentologically, an increase in allodapic limestones and shallow water fossil debris into basinal sections indicates progradation, possibly due to a lowstand. These data indicate that there is no obvious relationship between radiolarian and graptolite faunal turnovers in the mid Wenlock, irrespective of their coexistence in surface waters. Although radiolarians appear stressed at the Lundgreni Event, they recover by the early Ludlow. Decreased radiolarian abundance directly following the Lundgreni Event appears to be related to a shoaling event shifting radiolarian-rich facies basinward.

O'DOGHERTY, L., RODRIGUEZ, C. R., GURSKY, H. J., et al. 2000. New data on lower carboniferous stratigraphy and palaeogeography of the Malaguide complex (Betic Cordillera, Southern Spain). Comptes Rendus de l'Academie de Sciences Serie IIa: Sciences de la Terre et des Planetes 331 (8), 533-541. The Malaguide basement is formed by a thick, strongly deformed but weakly metamorphosed sedimentary succession of ?OrdovicianCarboniferous age, mainly made of basinal mudstones and turbidites, which includes a thin but conspicuous Lower Carboniferous chert-limestone interval (Falcona formation). The chert member (ribbon radiolarites) yielded, for the first time in Southern Spain, Tournaisian radiolarians. The Visean age of the limestone member is refined by conodonts. This formation is related to a period of generalized pelagic sedimentation, caused by relatively high sea level, low clastic input and high equatorial productivity, which preceded the closure of the Palaeotethys basins due to the Variscan orogeny.

O ' D O G H E R T Y , L. & GO R I C A N , S. 2002. Protunuma quadriperforatus n. sp., a new species of Jurassic Radiolaria. Micropaleontology 48, 35-41. Protunuma quadripeiforatus n. sp. is a tricyrtid Protunuma Ichikawa and Yao (Radiolaria, Nassellariina) characterized by a large subspherical abdomen with well-developed tetragonal frames on the external surface. Phylogenctically, it represents an advanced morphotype of Protunuma, but the external ornamentation with distinctive tetragonal frames resembles some contemporaneous species of other genera, i.e. Striatojaponocapsa conexa (Matsuoka) and Tricolocapsa tetragona Matsuoka. Protunuma quadriperforatus n. sp. occurs in latest Bajocian - early Bathonian to middle Bathonian low-latitude assemblages from the Mediterranean region and Japan.

O R C H A R D , M. J., CO R D E Y , F., RU I , L., et al. 2001. Biostratigraphic and biogeographic constraints on the Carboniferous to Jurassic Cache Creek Terrane in central British Columbia. In: (STRUIK , L. C. & MAC INTYRE , D. G. eds). The Nechako NATMAP project of the central Canadian Cordillera--Le projet NATMAP Nechako de la Cordillere canadienne centrale. Canadian Journal of Earth Sciences = Revue Canadienne des Sciences de la Terre. 38/4: 551-578

O'D OGHERTY , L. & GUEX , J. 2002. Rates and pattern of evolution among Cretaceous radiolarians: relations with global paleoceanographic events. Micropaleontology 4 8 , 1-22.

Conodonts, radiolarians, foraminiferids, and corals provide constraints on the geology and tectonics of the Nechako region. They also support the notion that the Cache Creek Terrane i s allochthonous with respect to the North American craton. The 177 conodont collections, assigned to 20 faunas, range in age from Bashkirian (Late Carboniferous) to Norian (Late Triassic); 70 radiolarian collections representing 12 zones range from Gzhelian (Late Carboniferous) to Toarcian (Early Jurassic); 335 collections assigned to 11 fusulinacean assemblages (with associated foramalgal associations) range from Bashkirian to Wordian (Middle Permian); and two coral faunas are of Bashkirian and Wordian age. The fossils document a long but sporadic history of sedimentary events within the Cache Creek Complex that included two major carbonate buildups in the Late Carboniferous (Pope limestone) and Middle Permian (Copley limestone), punctuated by intervening Early Permian deepening; basaltic eruptions during the mid Carboniferous and mid Permian; the onset of oceanic chert sedimentation close to the Carboniferous-Permian boundary and its persistence through the Late Triassic (Sowchea succession); latest Permian and Early Triassic mixed clastics and volcanics (Kloch Lake succession); Middle and Late Triassic reworking of carbonates (Whitefish limestone), including cavity fill in older limestones (Necoslie breccia), and fine-grained clastic sedimentation extending into the Early Jurassic (Tezzeron succession). Tethyan, eastern Pacific, and (or) low-latitude biogeographic attributes of the faunas are noted in the Gzhelian (fusulines), Artinskian (conodonts, fusulines), Wordian (fusulines, corals, conodonts), and Ladinian (conodonts, radiolarians). The Cache Creek Terrane lay far to the west of the North American continent during these times.

We present a new approach for analyzing the turnover rates of Cretaceous radiolarians recorded in pelagic sequences of western Tethys, The analysis of major extinction-radiation events and the fluctuation of diversity are compared with major paleoceanographic events and variation of diversity in dinoflagellates, calcareous nannoplankton and ammonites. There is an extraordinary correlation between biotic changes and sea level changes, temperatures, O, C and Sr isotopes, phosphorus accumulation rates and anoxic episodes. This reveals a predominantly abiotic control on the evolution of radiolarians. The rate of turnover and the diversity through time of two major orders of radiolarians (nassellarians and spumellarians) exhibits (1) the quasi-parallelism of their diversity curves, excluding a direct competition between them, (2) greater resistance of spumellarians to extinction during the early stage of extinction intervals and (3) a stronger post-extinction recovery of nassellarians. Evolutionary rates of radiolarians can be a good means of monitoring global environmental changes and allowing us to understand more clearly the relationship between plankton evolution, climate and pale oceanographic processes.

O'DOGHERTY, L., MARTIN, A. A., GURSKY, H. J. & AGUADO, R. 2001. The middle Jurassic radiolarites and pelagic limestones of the nieves unit (Rondaide complex, Betic Cordillera): Basin starvation in a rifted marginal slope of the Western Tethys. International Journal of Earth Sciences 90 (4), 831-846. Middle Jurassic radiolarites and associated pelagic limestones occur in the Rondaide Nieves unit of the Betic Cordillera, southern Spain. The Rondaide Mesozoic includes: (a) A thick succession of Triassic platform carbonates, comparable to the Alpine Hauptdolomit and Kossen facies; (b) Lower Jurassic pelagic limestones comparable to the Alpine Hierlatz and Adnet facies; (c) the Middle Jurassic Parauta Radiolarite Formation, described herein; and (d) a thin Upper Jurassic-Cretaceous condensed limestone succession. The Parauta Radiolarite Formation and associated limestones were studied with respect to stratigraphy, petrography, micropalaeontology (radiolarians, calcareous nanno- and microfossils) and facies. Radiolarite sedimentation occured in the Middle Bathonian in a restricted and dysoxic deep Nieves basin, perched in the distal zone of a continental margin fringing the Tethyan ocean. This margin was adjacent to a young narrow oceanic basin between the South-Iberian margin and a continental block called Mesomediterranean Terrane. The Nieves basin was part of a marine corridor between the Proto-Atlantic and Piedmont-Ligurian basins of the Alpine Tethys. The regional tectonic position, the stratigraphical evolution since the Triassic, the age and the nature of the Mesozoic facies and the palaeogeographic relations to adjacent domains show striking analogies between the Betic Rondaide margin and coeval units of the Alps.

P ISIAS, N. G., MIX, A. C. & HEUSSER , L. 2001. Millennial scale climate variability of the Northeast Pacific Ocean and Northwest North America based on Radiolaria and pollen. Quaternary Science Reviews 20 (14), 1561-1576. Radiolaria and pollen abundances in marine sediment cores from the northeast Pacific are used to reconstruct oceanographic and continental climate change during the past glacial cycle (0-150 kyr). These data allow direct comparison of the climate response of continental and oceanic systems. Detailed ∂ 18 O and AMS- 1 4C measurements provide a link into global stratigraphic frameworks. Canonical correlation analysis extracts two modes of variation common to both the Radiolaria and pollen records. The first mode of variation correlates an assemblage of Radiolaria associated with coastal upwelling with increased redwood, western hemlock, and alder pollen. This association is consistent with the modern relationship between coastal upwelling, coastal fog and redwood forests. A second canonical mode relates an oceanic fauna now found in highest abundance in the far North Pacific with reduced pine and western hemlock pollen abundance. Comparison of these records to an ice core ∂18 O record suggests that at wavelengths >3000 years, warm events in Greenland are correlated to intervals of increased coastal upwelling off Oregon, decreases in importance

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of very cold North Pacific fauna (suggesting warming), and increases in pollen associated with wetter coastal environments. Radiolarian based sea-surface temperature estimates suggest that the variability of the northeast Pacific on this time scale is about 2 ° C. Warming in the coastal regions reflects reduced advection of the California Current, but is moderated by increases in cool coastal upwelling. We infer that the response of the northeast Pacific to millennial scale climate changes is related to changes in atmospheric circulation at mid- to high latitudes. Preliminary analysis suggests that oceanic variability off Oregon at wavelengths