Valanginian to Barremian benthic foraminifera from

Valanginian to Barremian benthic foraminifera from ODP Site 766 (Leg 123, Indian Ocean) Ann E. L. Holbourn and Michael A. Kaminski Research School ofGeologiclIf ami Geophysical Sciences Birkbeck College mul Uuivery;/y Col/ege wmlo,(, Gower Siren. London IVCI£ 6BT. U.K.

ABSTRACf: A Valan ginian [0 Barremian mahy"] foraminiferal as.~mbJage (I J g ("JIll l>elonging to 51 genera) is documented from ODP Site 766, drilled ncar the fOOl of the Exmouth Plau'au off northwest Australia. The majority of taxa arC cosmopolitan ,pecie~ previously described from Ihe borea l assemblages of nonh.em Europe and the northern margins of the Tethys, but 32 mxa could nOl be assigned to previously descri bed $pecies and are left in open nomendamrc. The chronomaligraphy of thi, ~c[ion is ba~d upon nannofo~_'ils. palynomorphs. and radioiJage (:onlains Plmwlaria crepid/l/aris. Pale/lilUl slIoc·re/acea. and ReillhQltle/ia Irojkeri. A major faunal discontinuity is observed al tile top ofthi~ assemblage between Cores 166A·32R and 166A-30R. probably associated with a depositional gap between tile late Hauterivian and tile Barremian. 4) The overlying Barrem ian assemblage is chardclcrized by Gm'elillella oorremilllw, Glomospira spp., and PsclldogulidryilJe/ia sp. This record enables long-distance comparisons of the strdtigraphic ranges of benthic foraminiferal species in the austral bioprovinoreal assemblages by the lack of diverse agglutinated taxa. As a result, benthic fornmini feml zonations established for the Lower Cretaceous of the nonhem Tethys and Tethyan DSDP sites could not be applied at Site 166. Taxonomic and biostratigrapbic differe!>Ces 8t Site 766 support the exi,tence or a taxonomically dislinc! Early Cretucoous 11US/1lI1 biopcovioce.

INTROD UCTION The biogeographic dis/(ibwion of various marine organisms in Lower Cretaceous sequences has enabled paleontologists 10 recognize the existence of two main bioprovinces during Early Creta· ceous ti me: a boreal bioprovince in high northern latitudes and a lethyan biuprovince in low tropical latitudes. The presence of a third main bioprovince in the south ern hemisphere - the austral bioprovince, wh ich was the southern hemi~phere equivalent to the cool boreal bioprovince - i ~, however, rarely mentioned in the literature as research has traditionally fOcused on boreal and tropical assemblages. For a long ti me. the Cretaceous foraminiferal microfaunas from Australia an d New Zealand were viewed as unusual and endemic, Even now, re lati vely little is knuwn about the microfaunas from the austral bioprovince and about their re lat ionship to those of the other two bioprovinces duri ng the Early Cretaceous. The recovery of Lower Cretaceous sedimentary seq ucnces rrom ODP sites in the Indian Ocean has, fortunately, provided new material for smdying the distribution of foraminifera in Ihe high southern latitudes. At OOP Site 766 diverse, well-preserved. bathyal asse mblages have been recovered from sediments as old as Valangi nian. in contrast to the predominantly marginal assemb lages previously described from epeiric basins in Australia and the Indian Ocean. The forami nifera from GOP Sile 766, therefore. offer a un ique inSight into the compoSition of deep-water benthic asse mblages during the Early Cretaceous, These assemblages also provide the opportunity to retrace the evolution o f one of the oldest continental marg ins in the world from its early rifting phase early

in the Cretaceous, when the supercontinent Gondwana fragmented and the Indian Ocean started 10 open, to its mature position in the Albian at the edge of II vast ocean. The main objective of this work is to conduct a detailed taltOnomic and biostratigraphic survey of the lesser-known Valanginian to Barremian benthic foraminifera al Site 766 and to compare them with beller·documented asse mblages from the Tethyan and boreal bioprovinces. Benthic foramin ifent are particularly useful for stratigraphy during this interval because planktonic species are absent. They are also imponant for paleogeographic and paleoceanographic reconstructions and for worldwide stratigraphic correlations (e_g. Bartenstein 1979).

PREVIOUS WORK Taxonomy and distribution of southern hemisphere benthic foraminifera A detailed study of Apti an-A lbian benthic foraminifera at ODP Site 766 was carried out by Haig (1992). The Valanginian-Barremian assemblages at th is site were examined on board ship: eight species were mentioncd in the ODP Site 766 Site repon (Ludden and Gradstein et al. 1990), No fun her work has foUowed these initial investigations. The ta:tonomy an d paleOecology of Lower Cretaceous benthic assemblages from high southern latitudes have been studied by sevcral aut hors, mai nly over the past 30 years. Crespin ( 1944. 1953, 1963) described the Aptian-Albian assemblages from epicontincntal seas of mainland Australia. Espitalie and Sigal (1963) compiled

micropaleolltolol;y, vol. 4/ , /10. 3, PfJ. /97-250, tex/-figllres /·3, plares 1·16. laMes /·2, /995

197

Am, E.L No/bOlli'll mtd Michael A. Kaminski: Valanginian 10 Barremilllt bel!lhicforamillifemfmm ODP Sile 766 (Leg /23, Indial! Ocean)

a detailed taxonomic and strat igraphic study of foram inifera from Upper Jurass ic and Lower Cretaceous deposits of the Maju nga Basin (Madagascar) that recognized 189 species. 54 o f them new. Ludbrook (1966) documented the forominifera l asse:mblages from the Greut Anesian Basin. G lobal distribu tion patterns were investigated by Sigal et al. ( 1970). who showed similarities between foraminifera from Upper Jurassic and Lower Cretaceous Gondwana contincntal lllargi n deposits o f Madagascar, India and Chile. In a series of papers. Scheibn(fOvo'i ( 1971a. 197 1b, 1972, 1974a. 1974b, 1976. \977) described Lower Crelaceous assemblages from the Great Anesinn Basi n and from DSDP Siles in the Indian Ocean. ScheibncrovA recogni7.cd the existence of:1II austrul biogeoprov ince in the southern hemisphere. According to Scheibnerovo'i. austral assemblages (in common with cool boreal a~se mblages) typica lly lacked plnnktOnic species and were dominated by aggl utinated foraminife rn nnd small simp ly ornamented calcareous forms. Scheibnerovo'i ( 1973. 1978) proposed that the austral biogeoprov ince, thm inc luded Australia. th e epicontinental seas of Gondwana and the C retaceous southern oceans. supponed a d istinctive cool-water microfaun a and that episodic south-lionh migrations caused s imilnriti c!.~ between austrn l and boreal fau nas. Lambert nnd ScheibncroYli ( 1974) compared Albian fo raminifera from Zul uland (Sou th Africa) and the Grent Anesian Basin (Australia) and concluded thnt they represented a typical, cool-water. austral fau na from shallow environments. Scheibnerovti ( 1974b) described the Aptian-Albian benthic foraminifera from DSDP Sites 259. 260 and 263 and compared them with coeval assemblages from India, Australia and Sout h Africa. KuzncL

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-=------..J

TEXT·AGURE 1 Location of S ile 766 00 the

I()y,~r

E.tmoulh Pl ateau (redrawn after Ludden, Gr.Klstcill 1:1 al. 1990). CountOUI"S in thousands of l!leICrs.

nonhern Telhyan margin. and was

ba.~ed

to a large eXlent on

comparison of North Atlantic low-Imilude DSDP sites with the Vocontian Trough. Moullade (1914) had previously developed u Lower Cretaccous 20nal ~chcme for the pelugi(.; facie s of the Mediterranean Province based on the Vocontian Basin and several other Slriltoypes and had also proposed ( 1979) a zonation for Ihe Valanginian in southeastern France based on bent hic foraminifera which wa~ correlated with ammonites. A zonal scheme for the Tilhooinn 10 Cenomanian of the non hem Tethyan margin. published by Weidich (1990), was based 00 the occurrence of o\'er 400 foraminiferal species from the Nonhern Calcareous Alps in B:lYnria and Aus tria. This monograph provides the mool eomplele taxonomic dala set for the norlhem Telhys. Wcidich's bioslnlligraphic scheme subdi vided the Lower Cretaceous into 10 Zones based on first occurrences or acmes of primarily calcareous benthic foraminifera. For the interval of interest fur this study. Wcidich recognised onl y three lOnes. in contrast to the 10 zones dcfim:d by Moullade. However, Weidich's zonal scheme is only tentatively correlated to the standard chronostratigraph y (therefore zonal bou ndarie.~ are indiealed by dashed lines). and further calibration orWeidich's samples by means o f plank IOnic microfossils is net:ded to refine the age of his zones. Riegntf and LUlerbacher (l989a) stud ied 22 tow lalilUde s ites situated in the northern hemisphere. but three sites from higher southern Ialiludes were also investigaced: Siles 249 and 261 in the Indian Ocean and Site 330 in the Atlantic Ocean. These au thors

devised a Lower Cretaceous benthic foraminiferal zonation thnt subdivided the Berria~ian to Cenomanian into six zones. based on the fi rs t occurrences of cenain taxa. The authors also reported the stratigraphic ranges of 31 cosmopolita n deep-sea species in both deep sea and continental margin sequence~. They ex tended Ihe known stratigraphie range of several other deep-sea laxa into older levels. Among them is the species Gave/ii/ella /mr,.em;{///{/. which was reponed from the base of Hauterivian and is the nominate taxon for their Hauterivian lOne. Moullude (pers. coman" 1994) has suggested. however. that the form reponed by Riegrllr and Luterbather may be a precursor of G, b(ll'remifma, which is known to have ancestors with FO at the Hauterivia n-Barremian boundary (cf. G, aff. oorremiwUl Moullade 1966, p. 73).

LOCATION ANn GEQLOGICALSETIING ODP Leg 123. Site 766 wa.~ drilled at latitude 19°55.92'S and longitude 11Oo27.24'E at the foot of the Exmouth Plateau, off northwestern Australia (text-fig. I). This site is located on an ancien t continental margin; it formed part of an extensive continental rift zone du ring the Early Cretaceous when the supercontinent Gondwana fragmented and the Indian Ocean staned to open. Approximately 300m of Valanginian to Albian sedi menL~ were recovered at Sile 766. The chronostratigraphy based on magnelostratigraphy, palynomorphs. radiolarians and benthic foraminifera wa~ l'Ompiled by Knmi nski el al. ( 1992). The Lower Cretaceous chronostratigraphy of Ho le 766A is shown in text-figure 2. The

199

AIIII £.L flu/bourn (wd Michael A. Kominski: Va/ongillitm to Borremillll bemhicjoramilli/erojrom ODP Site 766 (Leg 123, Illdion Oceoll )

Valanginian to Barremian interval (Sections I 23-766A-26R- 1 to 123-766A-49R-4) consists of approx ima[ely 250m dark greenish gray siliciclastics, which have been di vided into two main lithological subuni ts ( ili A and IIIB). A prominent seismic reflector marks the boundary between subu nits lilA and III B where [he lithology c hange.~ from clayslOl"Ies (above) to sandstones and siltstones (below). This unconformable surface. located at 307m below the sea floor. is charolcterited by onlap above and erosional tru ncat ion below and represents a major unconformity between the two subunits (Ludden, Gmdstein e[ al. 1990). The oldest subu nit 111 13 (Sections 123-766A-32R, CC to I 23-766A49R4) thickens to the southwest and is dominated by redeposited sandstones and siltstones with a few intercalated as h layers. [t has been interpreted as a prograding sy n-ri ft sedimentary wedge. composed mainly of volcanic and shallow marine grains derived from the outer Exmout h Plateau which had become elevated to the southwest due to therma l uplift of the rifting marg in (Ludden. Gradstein et al. 1990). This sed imentary sequence h as no equivalent On the Ex mouth Plateau where it coincides wit h a n unconform ity. Burner et al. (1992) proposed th ot it was deposi ted when thc Cuvier Ocean basin opened alld "Greater India" dri fted past Site 766 in the Va langinian-Hauterivian. High TOC values to about 1.6 wt% were recorded for subuni t 1118 nnd Rock-Eval pyrolysis indicated a terrestrial origin for Ihe orgnnic mailer. Subunit ili A (Sections 123-766A-26R- I [0 123-766A-32R. CC) is chnracterized by bioturbated claystones with abundant glauconitiC groli ns and roldiolarians, whic h suggest II lower depositional energy, possibly in a deeper and/or more stable environment. Thermal subs idence of the margin coupled wi th a sea-level rise and a major ridge jump probably cut off the supply of coarse clastics and led to the abandon ment or !.he prograding wedge system (subunit IUD) and to the deposi tion of a more hemipelagic sequence (Subuni t ili A) during the Barremian (Burner et al. 1(92). The characteristic TOC va lues, which are near I wt% for the claystones, are lower than in the basal subunit IIlB. From backt racking, sedimentation appears to have Started ut depths of about 800m and thc site probably remained near or above CCD level th roughout th e E:lrly Cretaceous; thc calcul ated sedi me ntation rates of60mfmy are high for subunit IIlB, but decr ease to IOm/m.y. for subu nit lilA (Luddc n. GroldSlcin et ul. 1990). METHODS Fifty-three sam ples (20 cc) from Cores 49R-04 to 26R-O l were processed by repeated dryi ng and washing in 1% Calgon SOlution. TIle washed resid ues were randomly divi ded into fractions wi th the hel p of a sample spl itter: the fractions were then s ieved (>25Omm. > 125 mm and >63 mm) and each picked for microfossils. When fossil ubu ndance allowed, a minimum of 300 forami nifera were picked pe r sam ple as we ll as other microfossils. The picked specimens were then sorted on cardboard slides for identification. These are housed in the Micropaleontology collections of University College London. Taxonomic comparisons were made with paratypes and holOtypes from Early Cretaceous foraminiferal COllections at the Senckenberg Museum in Frankfun (Banenstein and Bralld 1951 ; Bartenstein and Kaever 1973) and at the Institute for Palaeontology and Historical Geology in Munich (Weidich 1990). Site 766 assemblages were also com pured wi th coeval, Tet hyan ,lOd horeal assemblages from Atla ntic O DP Sites nnd cont inental Europe and with hi gh latitude, southe rn assemblnge from Ind ian O
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pI. 10. fig. 6. - SCHEIBNERovA 1976. pI. 37. fig. I.

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BlIrremioll bell/hic /oramillifera/rom ODP Site 766 (Leg 123. I"dillll Ocean)

HAIG 1982. pI. 7. fi gs. 16-17.

Description: Elongaled. uniserial. lapering test. triangular in crosssection wilh dist inctly concave lateral faces. Eight low chambers are separated by strongly arched. depressed sutu re~ which are steeply inc li ned downwards. Last chamber rou nded wilh simple apenure. Relllll,.ks: The specimens from Sile 766 clo...ely resemble T. excavaf(J Reuss, illuslrmed by Haig ( 1982) and T,.ibracltia allstratimlll Ludbrook illuslrated by Scheibnerova (1976). The specilIlens are also very similar to Tricadllella eXCllI'(l/l/ originally described by Reuss (1863) and il1uSlraled by Sliter ( 1980), Moullade (1984) and Weidich ( 1990) bUi are generally narrower, more lapered and lack a drawn-out apenure. Ri egraf and Lulerbacher (1989b) did nOI taxonomically differentime Tdstix TlIl1auica Shokhina 1960 and ils synonym T,.istix fallceota Sliter 1980 from the very variable species T. excavala Reuss 1863. Tri.'itix excllI'aW Reuss 1863, however, clearl y possesses a triangular cross-section with three nearly equal sides, while bolh T tlllwssica Shokhina 1960 and T tallceo/a Sl iter 1980 are unevenly quadrate (te~t wider than thick ) a~ illustrated by Weidich (1990). The pholOgraph o f 7: tunllSsiC(l Shokhina 1960 in Riegraf and Luterbacher ( 19&9b) is, unfonunate ly, too vague to clarify the mutter. Ronge (lnd OCC/lrrence: T,.i.wix excll\·ato Reuss has been recorded in the Valanginian-Barremian of the southwestern Atlantic (Sliter 1977), from the mid Albian in the nonhero Alps (Weid ich 1990), in the laIc Albian-Cenomanian of Papua New Guinea (Haig 1981) and in Ihe late Albian of Queensland (Haig \982). Scheibnerova also found Tribrachia all.ftralia"a Ludbrook in Aptian-Albian sediments at aDP siles in the eastern Indian Ocean (1974b) and in Albian sediments of the Great Australian Basin ( 1976). Family VAGINULlNIDAE Ehrenbe...,; 1838 Subfamily LENTICULININAE Chapman. Parr and Collins 1934 Genus LellliCll/irlCl L3marck 1%04 unliell/ina cirellmcidanea ( Benhelin 1880) Plate 6. figure 4 Cristellaricl cirulII/cidtllleo BERTI IELIN t 880. pI. 3. fig. I. L'!IIticu/illa circllmcidllllea

(Uerlhelin). -

JENDRYKI\-I' UGLEWICl.

longilUdinal ornamentation on the chamber walls. Elaborate, phyalinc, radiate apertu re at end of a narrow protuding neck. Remarks: Closely resembles more ornamented fonns illustrated by Neagu (1975) but general ly more flattened with a mOre elaborate npenure. Less involute and more nattened than specimens illustrated by Bartenstcin and Brend ( 1951). Rllnge lmd Occurrence: Late Valanginian-early Hauterivian in northwestern Germany (Darten~lei n and Brand 195 1). Hauterivian in Rumania ("eagu 1975). Late Valanginian-early Barremian in Tethyan and transi tional horeal facies of nonhern Europe (Banenstein 1977). Characterizes the upper Hau terivian assemblage at Site

766 Leli/ieu /ina h eiermanlli Bettcnstaedt 1952 Plme 6, figures 5a-8b Lemiclllilla l1eitrlllatllli BElTENSTAEDT 1952. pI. t, fig. 9- 10.

BART'ENSTEIN and BE1TENSTAEDT t962. tab. t8, pI. 39. fig. I. WEIDICH 1m. pI. 20. figs. 15-16. Descriptiol1: Thick. involute test wilh numerous chambers (usually 10 or more). Sutures arc curved. sirongly rniscd and fonn a thick, irregular umbilical callus. Radiate apertu re at the peripheral angle. Remarks: Number of chambers. prominence uf sutures and size of the callus vary significantly.

Ran ge {Ind Occurrence: Cosmopolitan species. widely recorded from the Hauterivian to lower Aptian in the Tethyan and temperate realms (Barten.\tein and Kovatcheva 1982). LeliliClliin" mllcrcnlisca (Reuss 1863) Plate 6, figures 9- IOb

Crisullaria lIIacrotiisca REUSS 1863 pI. 9. fig. Sa, b. Lemiculillli lIIacrodi.rCll ( Reu~s). - NEAGU 1975. pI. 45. fig.~. t-16.20;

pI. 47, fig.~. 25-26. - WEIDICH 1990. pl. 21. figs. 1-2. De.l'criplioll: In volute, strongly convex. lenticuline test with ex-

tremely large, dark. projecting umbilical disc. SUlUres are curved backwards and the periphery is very sharp with a narrow keel. Aperture radiate at peripheral angle. Rell/l/rh: Shows considerab le variab ililY (see L Roemer).

IIlllell.~teri

1975. pi. 13. fi gs. 5-1. Range and Occurrence: A cosmopolitan species. widely distribD escriplillll: In volute test. subcircular in oulline with 7-8 cham-

uted in the Early Cretaceous (Weidich 1990)

bers in the last whorl. Peri phery acute with a narrow kcel. sutures curved, nush in the early pan becoming faintly depressed. Aperture rad iate at peripheral angle and small. depressed umbilicus.

LenticIIUllO /1/m!nsleri (Roemer 1839) Plate 6, figure II a. II b

Remark.f: Keel development varies in specimens from Site 766.

Rolmlillll lII/1ellSltlri ROEMER 1839. pI. 20, fig. 29;•. b. Lenticlili/!{/ /lwens/e,.i (Roemer). -JENDRYKA-FUGLEWtCZ t975. pis.

Rallge {Illd Occurrtmce: Found in the Valanginian-Hauleri vian of Poland and in the Albian of France (Jendryka.Fuglewicz 1975). also in the Albian of the northern Alps (Weidich 1990). Lel/liell /illa guttata (Ten Dam 1946) Plate 13, figures 7-%e Lellliclilimr gll/taf{/ TEN DAM 1946. pi. 88. fig. 2. -

NEAGU 1975. pi. t-2;pl. 51. figs. 2-6, 12. t4. t8- t9, 23-25. I..cnliclllillli 8"l/lIl(. gllllatli (Te n D~Il1). - BI\RTENSTEIN and BRAND 1951. pI. 5./ig. tt6. 50.

fig~.

Description: Flallelled, carinate test wilh a tendency to become evolute. Sutures are marked by prominent carin ae or nodulose rows. Very ornamented forms lllay be tricarinate with additional

214

8.9.10. II. fi!s. 1-6. pI. 19. pI. 20. figs. 1-2. - BARTENSTElN and BOLLI 1986,~. 4. figs. 25-26.

Descl'iplion: Smooth, involute, convex, lenticuline test with 7- 12 chambers in Ihe last whorl. Flush, markedly curved sutu res coalesce into a large, dart, slightly projecting umbonal disc. Sharp periphery. radiale apcnurc at peripheral angle. Rell1arh: This very long ranging, cosmopolitan specie~ shows considerable variability. Jendryka-Fuglewicz (1975) has distinguished six morphotypes wit h stratigraphic significa nce from the Jur.:lssic \0 the Albian in Poland. Transitional forms lead to a wide overlap and stratigraphiC resolution depends on morphomet ric analysis. Bartell.~lein and Bolli ( 1986) have also emphasized the difficulty in dividing L. II1l1ensteri Roemer, L clI/tmlll Montfort.

M icrorxrleuntulogy. 1'01. 41. "0. J. / 995

L roill/aw Lamarck. L maerodisca Reuss. l... rot-Illeri Reu.~s and L sliba/a/(/ Reuss in to valid morphological and stratigraphical groups because SO many tronsitiona l fonns exist Mey n and Vespermann ( 1994) trem L ellN!lIbergi. L c:rassa. L impressa and L macrodi.fCCI as synony ms. Al Site 766 ex treme members of the L IIIlIell.fleri and L II/(Jcrodisco plexus are distinguis hable. and more refined morphological and strotigraphical resol ution might be achieved with the application of morphometries.

Runge (11,,/ OCCllrre"ce: A cosmopolitan species in the JurassicCretaceous (Jendryka-Fuglewic1. 1975). Lelllieu/ina II odosa (Reuss 1863) Plate 7, figure 2a. 2b R(l/m/illll /lodo.WI REUSS Ilj63. pI. 9. fig. 6;.1. b. Lemiculiuo not/om 1/(}(./OS(l (Reuss). _ BA((f£NSTEIN 1974b. pI. I. figs.

3-17; pI. 2. fig.'. 5·6. 9-12, 16·17. umlii"u/ilt(, IIIIi/IJ)'11 (Reuss). _ JENDHYKA-FUGLEWICZ 1975. pI. 12. figs. 4- 12.

Descriptioll : Small. involute. lest wi th 7-JOchambers in last whorl separated by thick. curved. raised sutures. Peripheral knot- like thickenings give the test a distinctive polygonal appearance. Radiate apertu re at peripheral angle.

Remurh: Un(.'Ommon at Site 766, most tests only ha\'e weak scul pture and fai nl thickeni ngs al the periphery in comparison with the plesi()(ypes of Bartenstein and Brand ( 1951) and Bartenstein and Kacver (1973). The variabilit y of the species and iL~ tendency to uncoil has led to considerable lallonomic confusion. Bartenstein (1974b) and Aubert and Bartenstein ( 1976) have idemified within the L lIodos(I Reuss plell us several subspecies and closely re lated species of straligraphie and/or biogeographic re levance. Some evolu te specimens are present at Sile 766. Their small number and poor preservation. however. prevent subspec ific idemifieation. R(llige tmd Occurrence: Widely distribu ted, but with very \'ari able stratigmphic occurrence. This species probably embraces several itcrutive forms that evolved in geographic isolation from a 101lgranging common ancestor such as Lelllicll/i"a IIIlIensteri Rocmer (Michael 1967. Bartenstein 1974b. Auben :md Bartenstein 1976. Wddic h 1990). Occurs from the late Jurussie 10 the l«0), Sample 766A-30R-03; IOO-102cffi.

5n.b

umiclililla/teienll(lIIlIi Bettenstlledt. (x40. x40), Sample 766A-45R-02: 109- 11 3cm.

lIa.b

umicu/illa IIIlIell.~teri (Roemer), (x60, x60). Sample 766A-47R-04; 114-I I9cm.

6

umicli/illa heierll/l/I/Ili Bettenstaedt (x40). Sample 766A-46R_04: I05- I IOcm.

228

Ann E.L Holbourn and Michael A. Kaminski

micropafeol1l%gy. I'of. 41. 110. 3. 1995

Piau 6

229

AIIII E.L. Holbourn and Michael A. Kaminski: Valallgilliall 10 Barremian belllhicforamini/erajrom ODP Sile 766 (Leg 123. Illdimi Ocean)

Range and Occurren ce: A cosmopolitan index spcdcs for the upper Valanginian (Banenstein and Brand 195 1) and upper Hauterivian in Rumania (Neagu 1975). Recorded from the Albian of Queensland (Haig 1982). Family POLYMORPHINIDAE d ' Orbigny 1839 Subfamily POLYMORPHI NINAE d' Orbigny 1839 Genus EOgllllulifUi Cushman and Osawa 1930

Range and Occurrence: Nonh Atla ntic, eastern Ind ian Ocean and Central Pacific in Valanginian-Albian sediments (Riegraf 1989). Globulina /acrima (Reuss 1845) Plate 15, figures 4a-5b Polymorphilllliacriwtf REUSS 1845, pI. 12, fig. 6a-c. Glob,,/i'I('/(lcrim(l (Reuss). - WEIDICH t990, pI. 26, figs. 25-26. Globulilla d.lnaima ( ReuSS) . - FOWLER and BRAUN 1993. pI. 9, figs. 4-5.

Eoguttu litla iclulI.lsae (Dieni and Plate 16, fig ure la, lb

Ma~sari

1966)

GllfmlilW ic1l11usae DlENI and MASSARJ 1966, pI. 6, figs. 29·31. NEAGU 1975. pI. 76. figs. 27-30; pI. 108, figs. 28·30.

Desaiplion: Slightly compressed, ovate test with elongate chumbers added spirall y in planes less than 900 apan. Depressed, oblique sutures and fine costate ornamentation. Remarks: Very rare. Ornamentation most similar to that illustrated by Dieni and Massari ( \966). Range and Occurrence: Upper Valanginian in Sardinia (Oieni and Massari 1966). Upper Hauterivian, Barremian and lower Aptian in Ruman ia (Ncagu 1975). Genus G/obu/ina d' Orbigny 1839

G/obl/lina buccu /ell la (Benheli n 1880) Plate 15, fi gure 6a, 6b PolYlllorpirina bflccu/ema HERTHELIN 1880, pI. 4, figs. 17-20. Globulilla hucculema (Berthelin). - RIEGRAF 1989. pI. 2, figs. 17-20.

Descripliol1: Moderately inflated tcst, pointed at the proximal end with thTt.'e strong ly overlapping chambers arranged along three planes. Sutures depressed and radiating, terminal apenure large and straight. Remarh. Identil;al to specimens from ODP Site 249 illustrated by Riegraf (1989) in pI. 2, figs. 17·20.

Descriplioll: Ovate test with rounded base and slightly tapering apenural end. Few rapidly increasing chambers separated by flu sh indistinct sutu res. Apenure large, radiate. RanKc and Occurrence: Albian to Lai C Cretaceous in the northern Alps (Weidich 1990). C retaceous in Europe and Gulf Cost o f USA (Fowler and Braun 1993). Globulina prisca (Reuss 1863) Plate IS, figures 7a-9 PolymorphillQ prisca REUSS 1863, pI. 8. fig. 8. Globulill(l prisca (Reuss). - BARTENSTEIN and BRAND 1951, pI. 10, fig. 286. - FOWLER and BRAUN 1993. pI. 9. figs. 8-10.

De.fcriplioll: Elongmed test, moderately inflmed and slightly pointed lit the prox imal end with three overlapping chambers arranged along three planes, Sutures slightly dcpressed and terminal, radiate aperture, Range and Oc:mrrefIC:e: A cosmopolitan species in the Early Cretaceous recorded in Germany, Netherlands, Eng land, Poland, Alaska, France, Norway (Fowler and Braun 1993). Genus Palaeopo/ymorphilla Cushman and Oz.uWII 1930

PaioeopolYIIIQrplrilla sp. I Plate 16, ligures 13· 15b Descriptio,,: Elongated test. broadly founded at the ba ( Barte n.~ tein

BARTENSTEIN and BRAND 1951. pl. 10.

NEAGU 1975, pl. 69.lil:s. 20. 21. 24.

many (Banenstein and Brand 1951), late Valanginian-early Hau· lerivian in Rumania (Neagu 1975).

Dolina cr. slt/ent" (Walker and Jacob 1798)

DescriptiQn: Unilocular. globular test wilh rounded apertu re on shon neck and smooth surface. Remark,v: Shape varies from eylindrical to slightly elongate.

Plate 16. figure 2 St:rpula sllicala WALKER lind JACOB 1798, pI. 14, fig. S. I.uglma slllclIill (Wulker and Jacob). _ WEID ICH 1990, pI. 45. ligs. 6. 14.

PLAT E 9

Saracerwrio /or/icosta Bettenstaedt, (x50), Sample

8a.b

766A-47R·Ol : 98· I03cm. 2

Sarocellario /or/ico,U(j Beltenstae:dt, (XSO). Sanl ple

766A-29R·03: 54-5&:m. 9

766A-45R-02: IQ9·11 3cm. 3

Saracenaria tOr/icosra Beltenslaedt. (>60), Sample

Saracenar;a tortico.fto Beltenslaedt, (xS5), Sample

lliI,b

Saracellario /or/ico.fla Bettenstaedt, (x65). Sample

IIa,b

Stjr(jcenario /or/icosw Beltenslaedl, (x60), Sample

766A· 32R-02; 104· 108cm. 7

234

Saracellariajorlicos/a Betlenslaedt, (X90), holotype.

Soracetraria prm'os/O\'le)!i Fursenko and Polenova.

(>< I 00. xl 05), Sample 766A-32 R-05: 5-Scm.

l'agiml linopsis rericil/osa Ten Dam, (>«0), Sample 766A-32R -02: 104-IOSc-m. VagiflllUllopsis I/eopachYl/o/a Bartenstein and Kaeve r.

Vagillu/illopsis hllmilis precursoria BanCnSlein nnd Brand. (xI20), Sample 766 A-4()R-O I : 84-88cm .

Vr.JgimlJillopsis feliell/osel Ten Dam. (xlOO). Sample 766A-43R-05; 13 1- 135cm .

13

VagilllllillorJsis sp .• (X I 50). Sample 766A--47 R-03; 253Ocm.

AliI! £.L Holbollnr twd Michael A. Kaminski

PlfHe 12

J

lIIicropaleOlll%8.1'. 1'01. 41, no. 3, 1995

141

Ann E.L flolbollfll and Michael A. KamiTlski: Valanginian to B{lrremklll benthic foraminifera/rom ODP Site 766 (Leg /23, Indian Oceall)

BElTENSTAEDT, F.. 1952. Stratigrdphische wieht ige Fordminiferen-A rten aus dcm BarrenlC vorwiegend Norwest- Deutsc hlands. Senckent>crgiana. )3(4-6):263-295.

- - - , 1963. Lower Crelaceous Arenaceous Fordminifera uf Austrdlia. Burenu of Mineral Resourees Geology and Geophysics of Australia. Bulletin 66: 1-110.

BERGGREN. W. A. and KAMINSKI, M. A. , 1990. Abyssal Agglutinates: BilCk to basics. In: ~Iemlebcn. C., Kaminski. M. A .. Kuhnt. W. and Scott, O. B.. Eels.. Palaeoecology. BiostratigraJily. Palaeoceanography and Ta:\O[)()my vf Agglutinuted fomminifent. NATO AS I Serie~C 327:53-75. Kluwer Academic Publi shers.

CUSHMAN, J. A. aru.l ALEXANDER, C. I., 1930. Some Vllgi",,!;,JUs and other foraminifera from the Lower Cretaccou.~ of Texas. Contribut ions from the Cu shrmm Laboratory for f omminifcnd Research. 6( I): 1- 10.

BORNEMANN. L. G .. 1854. Ober die Liasfomlation in der Umgegend von G\\ttillgell und ihre orgallischcn EinschlU ssc. Berlin. 1-77. BRADY. H. B.. 1879. NOles on some of the rtticul:trian Rhizopoda of the "CHALLENGER .. Expedition; Pan I. On new or linle k.nown Aren_ aceous types. Quarterly Journal of Microscopical Sciell(:es, 19:20-63. BRAND. E. ami OHMERT. W .. 1992. Die netl.gerippten Lenticulinen illl Dugger von Nordwe.,t_ und Slldwcsl- Deutschland. Senck.cnbergiana lelhae