First Conference of the Lower Cambrian Stage Subdivision Working Group ...... TIOU~DB 4: Protopharetra taissensis (OEDRENNE 1958), Girvanella sp.
• ,
THE LOWER-MIDDLE CAMBRIAN STANDARD OF WESTERN GONDWANA
Introduction, Field Guide, Abstracts, and Proceedings of the First Conference of the Lower Cambrian Stage Subdivision Working Group and I. G. C. P. Project 366 Ecological Aspects of the Cambrian Radiation
Edited by Gerd Geyer & Ed Landing
.. '
Beringeria Special Issue 2 WUrzburg 1995
:= --:':. ~ '>, "
..
1001' 366 C1IMBRIRN ECOLOGII
FIELD WORKSHOP
Faunas and depositional environments of the Cambrian of the Moroccan Atlas regions GERD GEYER, ED LANDING
&
WOLFRAM HELDMAIER
GEYER, G., LANDING, E. & HELDMAIER, W. 1995. Faunas and depositional environments of the Moroccan Atlas regions. - Bcringcria
Special issue 2: 47-119, 26 text-figs.; WOrzburg. Addresses of the authors: Dr. G. GEYER & W. HELDMAIER, Institut fUr PaHtontologie, Baycrischc Julius-Maximilians·UnivcrsiUu.. Plei~ chcrwall 1,0-97070 WUrzburg; Or. E. LANDING, New York State Geological Survey. New York State Museum, Empire Slate Plaza, Albany, N.Y. 12230, U.S.A.
Introduction This field workshop emphasizes stratigraphy, paleoenvironment, biostratigraphy, sequence boundaries, volcanic ash occurrence, and potential for intercontinental correlation of a number of the most important Cambrian sections of the Moroccan Atlas regions. The arrangement of the sections visited during the workshop from May 3 to May 12, 1995, is roughly stratigraphic and begins in the western Anti-Atlas with the lowest Cambrian at Tiout, the lower part of the trilobite-bearing Cambrian at Tazemmourt, complete sections through the trilobite-bearing Lower Cambrian and lower Middle Cambrian at Amouslek and the western Lemdad syncline, the upper Lower Cambrian and a considerable part of the Middle Cambrian in the eastern Lemdad syncline, at Ourika Wawrmast, and
Tarhoucht, and finally a section with the Middle Cambrian resting on the Precambrian basement at the lbel Arhouri in the east-central Anti-Atlas. Additional stops illustrate the lateral variation of the sub-trilobitic Lower Cambrian in the central Anti-Atlas. Information on the stops includes a summary of the lithologic sequence and, if available, a complete list of faunas found at successive levels. The sample numbers with the prefix F refer either to the faunal levels of HUPE (1953, 1959) or SDZUY (1978), respectively; sample numbers with a comma indicate a precisely measured level above the base of the section or unit; other samples refer to horizons determined by GEYER (e.g., 1986, 1988b, 1990c) or to recent collections by the authors.
Contents May 3. Tiout Section May 4. Tazemmourt Section May 5. Amouslek Section May 6-7. Lemdad Syncline May 6. Section Le I May 6. Section Le II May 6. Section Le IV May 7. Section Le XI May 7. Fossil record of additional sections May 8. Sirwa region May 8. Id Boukhtir section May 9. Section Ait Saoun-Tizi n'Tiniftffi May 9. Ourika Wawrmast sections May 10. lbel Arhouri section May 11. Tarhoucht section
50 60 63
73 74
81 89 89 97 99 99 101 102 107 112
G.
48
GEYEK,
E.
LANDING
& W.
IIEI.I)MAIER
.~
•
,
, , ,
,
-
-
,
::: "'doo.oo
100
~:;;@f{i2:~ ~~ __
1
I I
!t...,.:~;;::,;.
~
.\..,~
.. ~~::::\ o lithologic sequence
100 % o
lithology: volume distribution
iiii...~'O:""-...~20 m a l
bed thicknessl bank set thickness! litho-sequences
2
3
height of bioherms
In
1->50 (jm 3 1",2
bioherms: relative volume
Neoprotero-
The figure variations in
iflustrates lithology,
bed thickness, biohenn volume, and relative bioherm volume from the upper Adoudou through lower Amouslck Fonna-
r.-~
0-
4.
zoic(?)-Cambrian cyclicity in the Tiout section.
'-
~
5
fig.
o
tions. Modified alier MONNtNGER (1979) and GEYER (198%).
The Cambrian ofll1c Moroccan ;\llas regions
biostratigraphically insufficiently characterized. Only thc Dagl/inaspis Zone can be recognized with certainty at the top of the cxposed sequence. However, lithologic correlation with the nearby section of Tazemmourt (see below) pcrmits a tentative bracketing of the underlying Chol/ber/ella and Fallolaspis /azeIl1I11Ol/rlensis Zones. Part of the section representing the
Chol/her/ella Zone and the Fallo/aspis la:ell1l11ol/rtensis Zone are presumably lacking because of two faults that cross the sect ion. UNA & SIJZUY (1978) noted the presence of Lell1dadella liol//ensis and trilobites tentatively assigned to Bigo/inops from the lowest "thick limestone above the base" of the formation (see Fig. 2). Although no index fossil is known from these beds, the authors assigned the fauna to the Fallolaspis tazell1l11ol/r/ensis Zone and suggested the potelllial of the genus Lell1dadella as an index fossil to the zone. However, it should be noted that a Fallotaspis sp. cf. F lazell1l11ol/r/ensis has been found by E. LiNAN during the field workshop of MOROCCO '95 at T 14 of the Tiout Member. Cyclicity, facies, and depositional environments The cyclicity, which is visible in the Lower Cambrian sequence of the Souss basin, is especially well documented in the Lie de vin through Amouslek Formations of the Tiout section (MO INGER. 1979; SCII 111T, 1979a; TUCKER, 1986b; GEYER, 1989b). Cyclothems and smaller-scale cycles and rhythms are recognizable in the Lie de vin and Igoudine Formations (Fig. 4) as second to fourth order cycles. Simple rhythms or cycles of the Lie de vin Formation are some meters in thickness and consist of simple lithosequences. They may have been primarily controlled by the terrigenous input. Those cycles compose units tens of meters in thickness and include several lithosequences (MO NI GER, 1979). They may record variations in terrigeneous input and environmelll or
57
of terrigeneous material, whereas the rock types in the middle of the cycles are more-or-Iess pure carbonate and document limited detrital input (Fig. 5). On a smaller scale, the same is recognizable for the change from dolostones via dolomitic limestones to pure limestones, a trend which is further visible by an increase of the bed thickness and paralleled by more diverse algal build-ups (SCIIMITr, 1979a). Remarkably, the majority of cycles in the Lie de vin Formation are symmetrical, which points to very low wave energies and a fluctuating balance between sedimentation rate and basinal subsidence (MON I GER, 1979). C learly asymmetrical, t ide-dom inated cycles with a vertical succession that includes shaly calcareous marlstone - limestone - dolomitic marlstone shaly calcareous marlstone are developed in the upper sequence of the Lie de vin Formation. These modal cycles show variations that can be arranged according to lateral transgressive-regressive environmental trends (MONNINGER, 1979), but may also mark geographically widespread, coeval, aggradational shoaling cycles. MONNINGER (1979) and SCllMITr (1979a) related the supercycles to the relative algal volume in algalbearing beds of the Lie de vin and Igoudine Formalions (Fig. 4). In most cases, the relative algal volume reaches its maximum when the cyclothem thickness starts to decrease (MONNINGER, 1979). Stromatolites are distributed in regressive but absent in transgressive half-cycles (where teepee-structures occur frequently). Cyanobcterial build-ups are additional indicators of secular facies changes. Thus, a succession consisting of the sequence including low stromatolite biostromes - thrombol ites - branched columnar stromatolites - low bulbous build-ups parallels increasingly restricted facies (Mo NINGER, 1979; SCIIMITr, 1979a). In summary, the Lie de vin Formation at the Tiout
sea level changes.
section displays a remarkable, extremely shallow, low energy, schizohaline, microtidal environment with surprisingly regular changes in depositional processes. This unusual facies culminates in tidal flat dolostones with cyanobacterial laminites and evaporites now documellled by pseudomorphs after halite and gypsum, which indicate hypersaline depositional conditions. The facial contrast generally increases up-section and
A changing input of terrigenous detritus and environmental changes may also be responsible for the changing lithologies represented in the section. Each cycle starts and ends with a comparatively high content
is best seen in development of more and more lithologies. Purple shales, intercalated in the upper sequence of the Lie de vin Formation where a regressive trend is clearly indicated, suggest a change
climate and hence reflect changes in water depth and salinity (Fig. 5). These cycles in turn compose "supercycles" that are hundreds of meters in thickness. The laller are interpreted to be a response to regional trends in epeirogenic basin development or sea level fluctuations. The supercycles show a long-term trend which reflects either epeirogeny or trends in eustatic
G. GEYER, E.
58
LANDING
& W. HELDMAIER
OA
I.. ···~···. : A
A
o A
~L
L
o
supercycle 1111: longterm trends
cyclothems:
symmetric cycles
climatic changes or sea-level/epeirogenic variantions?
Fig. 5. Lithological clements that indicate cyclicity. Gradual magnification exhumes different orders of cycles. Modified from MONNtNGER (1979: Fig. II).
in water chemistry. Geochemical data on this interval were interpreted to suggest fresh water influx (MONNINGER, 1979), although the change in shale color may simply indicate a reduction in sediment accumulation rate and production of reddish shales with long residence time at the sediment-water interface. An increasing amount of carbonate from the Lie de vin Formation to the upper part of the Igoudine Formation and a synchronous decrease of detritic material are explained by growing distances from the shore with widening of the basin due to transgressive trends which locally and temporarily led to less restricted marine conditions. At the base of the Tiout Member, the change in microfacies from argillaceous dolosiltites and dark, micritic, often finely laminated limestones and dolostones to massive oolites, pack/wackestones, and marlstones with a high content of intraclasts indicates higher energy, most probably connected with increasing water depths and more normal marine conditions. It remains unclear whether this
change is created by an intracontinental event, regional climatic change, or epeirogenic changes. Foss iI reeo rd The following list indicates the fossil content of selected horizons. The prefix TIOU-M refers to the numbering of sample horizons by MONNINGER (1979), TIOU-DB to the archaeocyathans horizons of DEBRENNE & DEBRENNE (1978), TIOU-T to the trilobite sample horizons of SDZUY (1978), and TIOU-EB to samples horizons of E. BERNEKER (unpublished). A sevised taxonomy of the archaeocyathans is in DEBRENNE & DEBRENNE (this volume), where a complete Iist of the known archaeocyathans is given. AmOllslck Formation
Tt-M959: Daguinaspis Zone. Sponge spicules, trilobites, hyoliths, Renalcis sp., Gin>anella sp., EpiphylOl1 sp., Kordephylon
sp., undeterminable calcareous algae. Tt-M958, TIOU-l, Tt-3: Daguinaspis Zone. Microschedia amphitrUe GEYER 1994, Brevipeltel chouberti GEYER 1994, DQ-
The Cambrian of the Moroccan Atlas regions
guinaspis abadiei IIUPE 1953, Daguinaspis sp., Marsaisia robauxi HUPE 1953, Resserops sp., hyoliths, numcrous small Planolites tubes. TIOU-EB 1/44a: Archaeocyathans, Renalcis sp.,l:.piphyton sp. Tt-M896: Trilobites. Tt-M883: Trilobite hash. TIOU-SZI (-Tt-M869): Brevipelta sp. ef. B. chouberti GEYER 1994, Fallotaspis sp., hyoliths, trace rossils. TIOU-M869: Chaneelloriids. TIOU-SZla (-TIOU-M867): Archaeocyathans, lingulids, trilobites. hyoliths, I-Iyo/ithellus sp. cr. J-I. m;cans BILLINGS 1872. TIOU-M860: Probably Pallolaspis ta:emmourtensis Zone. Lemdadella tioutensis LINAN & SDZUY 1978, Bigotinops? sp. TIOU·M856: Nyolithellus? sp. TIOU-T 17: Eofalloraspis n. sp. Tiout Mcmber
TIOU-DO 24d (TIOU-M849): Obolcllid brachiopods. TIOU~DB 23: £rismacoscinus primus (DEDRENNE & DEBRENNE 1978), Protoplwretra laissensis (DEDRENNE 1958). Nochoroicyatillis crassus (DEB RENNE 1961), Agastrocyathus gregarius DEIJRENNE 1961, Neo!oculicyotlws magnus DE. BR£NNE, Protopharetra c;rcu!a (DEBRENNE 1964), £rismacoscinusfasciola (DEBRENNE & DEIlRENNE 1978), RetecosciIIIIS minutus (DEll RENNE 1959), T1U1mlifimgia marOCW/{I DE. IlRENNE 1978. TIQU~DD 21: ProlOpharetra taissensis (DEBRENNE 1958), 1'1'0toplwreta sp. afT. P. grandicaveala VOLOGDIN, Protopharelra c:ircliia (DEB RENNE 1964). 'nOU-DB 20: Afiacyatlllls composilliS DEBRENNE 1961, ProlOpharetra circultl (DEDRENNE 1964). TIOU-T 14, EO 1/42a: Eofalloraspis sp., Fallotaspis sp. ef. F tozemmourtellsis I-!UIlE 1953, Renalcis sp., Epiphyton sp. TIOU-T 13x (TIOU-M842): Brachiopods, trilobites. TIQU-DD 19 (TIOU-M842): Erismacoscinus primus (DEB RENNE & DEBRENNE 1978), ErismacoscifwS filsciola (DEURENNE & DE. IlRENNE 1978), Protopharetra spp., Neoloculicyatlllls magnus DEllRENNE & DEBRENNE. TlImulifimgia marocana DEBRENNE & DEBRENNE 1978, Ifyolithellus sp. cf. 1/. micans BILI.INGS 1872. TIOU.-r 12, DB 18. EB 113 7: Neoloclllicyathus magnlls DEIlRENNE & DEBRE NE, Tllttllllifungia marocana DEBRENNE 1978, £ofa/lotaspis sp., Renalcis sp. TJOU-DB 17: Neoloculicyathus magnus DEBRENNE & DEURENNE 1978, Tllmulifungia marocana DEBRENNE & OEDRENNE 1978, Afiacyathus compos;ws (DEDRENNE J961), Nochoroicyatlws sp., Protoplwretra circula (DEDRENNE 1964), £rismacoscinlls fascio/a (DEBRENNE 1978), Retecoscbllls mimI/us (DEIJRENNE 1959), Dictyocyatlllls stipaws (DEll RENNE 1964). Tt-B 17 (base of TIOU-M842??): Arehaeoeyathans, /-Iupetina sp. ef. /-/. aniiqua SOZUY 1978, Ifyolithelllls sp. cf. II. miCall.f BILLINGS 1872. TIOU-EB 1/35: Archaeocyathans, Renalcis sp. TIOU-ED 1/32: Archaeocyathans, sponge spicules, trilobites, Renalcis polymorphum (MASLOV), "Girvanella" sp. TIOU-EB 1/31: Archaeocyathans, sponge spiculcs, chancclloriids, trilobites, Epiphyton sp. . T10U-DB 15-16, Ell 1/30: £rismaeoscinus primus (DEIJRENNE & DEIJRENNE 1978), Neoloculicyatlws magnlls DEBRENNE & DEll RENNE, ROllmdocyatlllls sp., Protopharetra circula (DEIlRENNE 1964), Erismacoscinus fasciola (DEURENNE 1978), Tumulifimgia mllrocana DERRENNE & DEBRENNE 1978. DictyocyOlhus stipatus (DEURENNE 1964), Afiacyatlws pruvosti DEBRENNE 1964, Agastrocyatlws gregarills DE. BRENNE 1961, trilobit(.is. Renalcis sp. TIOU-T 10: Eo/allolaspis tioutens;s SOZUY 1978 (type locality and
59
stratum). TIOU-DB 14, EB 1/28: £rismacoscbws primus (OEORENNE & DEBRENNE 19.78), Afiacyathlls compositus (DEDRE E 1961), Neo/oculicyatlllls magnus DEDRENNE & OEDRENNE, Pro~ topharetra sp. afT. P. grand;caveata VOLOGDIN. Archaeopharetra sp., Tumulifungia marocana DEDRENNE & DEBRENNE 1978. Renalcis sp. TIOU-OB 13: Afiacyatlws compositus (DEURI:NNE 1961), AgastrocyatlllIs gregarills DEDRENNE 1961, Tumlllifimgia marocana DEDRENNE & DEBRE NE 1978. TIOU-OB 12: Erismacoscinus primus (DEBRENNE & OEBRENNE 197~), Ajacicyathellus? Sp.. Afiacyatlllls compositus (DEB RENNE 1961), Agaslrocyallllls gregarius DEBRENNE 1961, Protopharetra circula (DEDRENNE 1964), Nochoro;~ l.J'athus crassus (DEDRENNE 1961). TIOU-T 9, EB 1/24: Brachiopods. Eofallotaspis sp.. Rena/cis sp. ef. R. novum, Kordephyton sp., Girvanella sp. TIOU-DB II: £rismaeoscinus primus (DEJ3RENNE & DEIJRENNE 1978), Erismacoscinus filsciola (OED RENNE 1978), ROlllndo~ cyathus sp., Neoloclilicyathlls magnu.fj DEBRENNE & OEDRENNE. TIOU-DB 10: Protopharetra laissensi,fj (DEBRENNE 1958), Afia~ cyallws sp. TIOU-EB 1/18: Erismacoscinus 51'., spicules. 'nOU-DB I, Ell 1117: Erismacoscinus prim/IS (Dr:J3RENNE & DEIlRENNE 1978), Protopharetra lll;ssensis (DEARENNE 1958), Afiaeyathlls composif/ls (DEUKENNE 1961), Agaslroeyalh"s gregarius DEBRENNE 1961, NeoloculicyOllms magnus DEI3RENNE & DEBRENNE, Protopharetra sp. afT. P. grandica~ \Ieata VOLOGDIN, Protopharetra circula DEIlRENNE 1964. Ar~ chaeopharetra sp., Tumulocyathidae, Rena/cis sp. TIOU-DB 2, EB 1/16: ROlUndocyothus sp., Erismacoscinus primus (DEBRENNE & DEBRENNE 1978), Afillcyatlms composilUs (DEBRENNE 1961), Ne%culkyotlllls maglllls DEllRENNE & DEBRENNE, Agastrocyathus gregarills DE13RENNE 1961, Renalcis sp. TIOU-EB 1/15: Renalcis sp., Girvanellll sp. TIOU-DB 3: Afiacyathus sp. cr. A. compos;llls (DEDRENNE 1961), Protopharetra taissellsis (DEDRENNE 1958). TIOU~DB 4: Protopharetra taissensis (OEDRENNE 1958), Girvanella sp. TIOU-DO 5: Chancelloriids. TIOU-T 5 (TIOU-M800): Brachiopod. TIOU-T 4, DB 7: Erismacoscinus primus (DEDRENNE & DEDRENNE 1978), Erismacoscinus sp., Eo/allotaspis prima SDZUY, 1978 (type localiTy and stratum). TIOU-DB 8, EO 1/1 (TIOU·M797): Lowest arehaeoeyathans: Nochoroicyathus cribrolUs (DEORENNE & DEBRENNE 1978), £r;smacoscinus primus (DEURENNE & DEDRENNE 1978), Erismacoscinus sp.; trilobite hash, "Renalcis" sp. TIOU-T 3 (TIOU-M795): Trilobites. TIOU-T 2 (TIOU-M795): Trilobites. TIOU-T I (TIOU-M790): Lowest determinable trilobites: lIupetina antiqua SDZUY 1978. Lower member of Igoudine Formation
TIOU-M760: Shells, probably trilobitie. TIOU-M755: Ourrows. TIOU-M75 I: Shells, probably trilobitic. Tt-M747: Worm tubcs, f1yolilhellus sp. cf. J-l. ",icans BILLINGS 1872. Tt-M724: f-1yolithellus sp. cr. H micans BILLINGS 1872. Lie de yin Fomlation Small burrows and burrow mouling arc known rrom a considerable number of marly siltstones (e.g., Tt-M687).
G. GEYER, E.
60
LANDING
& W. 1-IELDMA1ER
May4
TAZEMMOURT SECTION Setting
Lithologic sequence
The Tazemmourt section is south of the village of
The exposed sequence includes most part of the Igou-
Tazemmourt, about 10 km SSE of Taroudannt on the
dine Formation and most of the Amouslek Formation.
Taroudannt
The sequence consists mainly of an altemation of
map
sheet
(Lambert
coordinates
171.4/382.4). It lies on a marked northerly prolonga-
limestones, dolostones, and shale units.
tion of the Anti-Atlas. The rocks dip northward, and
The basal part includes the upper part of the Tiout
the top of the section at Tazemmollrt is covered by the
Member and is the best example of that member apart
alluvials of the Souss plain (Fig. I). The base of the
from the Tiout section. It contains a number of ar-
section about 2 km south ofTazemmourt is in an east-
chaeocyathan-bearing beds, which were studied in de-
west striking valley, which lies in the Igoudine For-
tail by DEBRENNE (see references above and DE-
mation. The conspicuous transverse ridge north of that
BRENNE & DEBREN 1', this volume). In addition, trilo-
valley is formed by limestones that lie about at the
bites (assigned to the Eojallotaspis Zone) occur as
level of ABADIE'S unit 17.
well. TIle shales are generally green in the lower part of
Introduction and summary
the section, with purple portions in units 20 to 28.
Due to its accessibility, the Tazemmourt section re-
Further up-section, the shales are less distinctly green
ceived a great amount of interest in the first period of
and become progressively paler. Relatively pure lime-
research on the Cambrian of the Anti-Atlas. It was the
stones are found in the basal part of the section.
first section studied by J. ABADIE in 1949. He mea-
Rubbly, "scoriaceous" limestones are intercalated as a
sured the section, which was first published by Hurl'
series of intervals from units 17 to 29 and units 48 to
(1953: Fig. 7) together with a lithologic log. HUPE
56. These intervals represent diagenetic growth of car-
(1953, 1959) completed more detailed studies on the
bonate in shell hash and clastic layers, as well as bur-
trilobite faunas, which had first been dealt with in a
rowed
preliminary paper by Hurl' & ABADIE (1950). In
chaeocyathan-algal associations are most frequently
HUPE's first monograph (1953), a number of holotypes
found at the top of the section (units 60, 62, and 64)
were chosen from the Tazemmourt section, including
and display a different ecosystem that those from the
those for such important species as Fallotaspis tazem-
base. Dolomitic limestones and dolostones are especi-
mourtensis, F. typica, F. longa, F. longispina, F. planospinosa, Choubertella lata, C. spinosa, Daguinaspis ambroggii, D. latifrons, Pararedlichia pulchella, P. rochi, P. subtransversa, Resserops brevilimbatus, Marsaisia parvifrons, and Bigotinops dangeardi. The
ally frequent around 100 m below the top of the sec-
archaeocyathans have been described in detail by DE-
DEBRENNE & DEBRENNE (this volume).
layers.
Biohermal
limestones
with
ar-
tion. The list of trilobites follows Hurl' (1953, 1959; nomenclature partly revised herein), and is supplemented by data from SDZUY (1978) and unpublished data. The nomenclature of the archaeocyathans is from
BRENNE (1959, 1960a, 1964; ROZANOV & DEBRENNE, 1974; DEB RENNE in DESTOMBES et aI., 1985), and a number offorms were first described from the section. Nevertheless, the stratigraphic interval that is ex-
283 m to top: Green shales. F II: Antatlasia hollardi HurE 1953, Antatlasia
bourgini HUPE 1953 (type locality and probably
posed in the section is fairly limited and includes the
type stratum).
Tiout Member of the Igoudine Formation and most of
FlO: Fallotaspis typica Hurl' 1953 (type local-
the Amouslek
Difficulties arise from
ity and probably type stratum), Antatlasia hol-
uncertainties of the published lithologic logs. Pub-
lardi Hurl' 1953, Resserops (Resserops) breviIimbatus Hurl' 1953, Marsaisia sp. cf. M. 1'0bauxi Hurl' 1953.
Formation.
lished sections (ABADIE in HUPE, 1953; HUI'E, 1959; HOLLARD, 1985) differ from each other in a number of details, especially in the lower third of the section. The
275-283 m: Limestone beds with archaeocyathans.
section shown on Fig. 6 is mainly based on the section
242-275 m: Three limestone complexes with archaeo-
figured by Hurl' (1959) but includes additional, partly
cyathans, separated by greenish slaty shales. Upper shale unit (63) yields obolt;lIid brachiopods,
unpublished information.
The Cambrian of the Moroccan Atlas regions
F10
65
63
250m60
~~~~~ i
59
F9
57
F8
56 55
53
F7 F6
51 -
F 5 CH 11
49
F4
48
200 m-
~;p5~9
37
33~~~~~!6 150m-32 ~ ~
F3
@
28
F2
z
o
-
I-
o
:2
o-
I-
Om
Fig. 6. Generalized lithologic sequence of the Tazcmmourt section, based all data frolll ABADIE in HUPE (1953) and HUI'E (1959). Fossil "sample" horizons (prefix F) refer to I-lurE'S (1953, 1959) levels.
Numbers without prefix indicate the units of ABADIE in HUPE (1953) mentioned in the text. Sec Fig. 8 for legend.
61
the limestone units (60 and 62) have the archaeocyathans (DB 20) Mennericyathus echinus (DEBRENNE 1964), Protophareta gemmata (DEBRENNE 1964), Afiacyathus pruvosti DEBRENNE 1964, and Dictyocyathus stipatus DEBRENNE 1964. 228-242 m: Green, slaty shales. Upper part of shales (unit 59) with F 9: Marsaisia robauxi HUPE 1953, Resserops uncioculatus HUPE 1953. Lower part of shales (unit 57) with F 8: Resserops I/nciocl/latus HUPE 1953. 225-228 m: Thick beds of rubbly limestone (Calcaire scoriace) 218-225 m: Green shales with bed of Calcaire scoriace at the base. Shales (unit 55) with F 7: Daguinaspis ambroggii HUPE & ABADIE 1950, Marsaisia parvifrons HUPE 1953. 214-218 m: Green shales, with Calcaire scoriace bed at the base. Shales (unit 53) with F 6: Daguinaspis ambrogglf HUPE & ABADIE 1950 (type locality and probably type stratum), Daguina;pis latifrons HUPE 1953 (type locality and type stratum), Resseropsfalloti HUPE 1953. 211-214 m: Green shales, with Calcaire scoriace bed at the base. Shales (unit 51) with F 5: Brevipelta chouberti GEYER 1994, Daguinaspis ambroggii HUPE & ABADIE 1950, Daguinaspis subabadiei HUPE 1953 (type locality and type stratum), Marsaisia robauxi HUPE 1953. TAZE-CH 11: Brevipelta chouberti GEYER 1994, Daguinaspis abadiei HUPE 1953, Daguinaspis ambroggii HUPE & ABADIE 1950, Marsaisia roballXi HUPE 1953, Resserops (Resserops) bOl/rgini HUPE 1953, burrows. 204-21 I m: Green shales, with Calcaire scoriace bed at the base. Shales (unit 49) with F 4: Daguinaspis abadiei HUPE 1953 (type locality and type stratum), Marsaisia parvifrons HUPE 1953 (type locality and type stratum), Resserops brevilimbatus HUPE 1953 (type locality and type stratum). Archaeocyathans (DB 18): Neoloculicyathus abadiei (DEBRENNE 1959), Mennericyathus echinus (DEBRENNE 1964), Erismacoscinus marocanus DEBRENNE 1958. 185-204 m: Alternation of archaeocyathan-bearing limestones, Calcaire scoriace beds, and green
62
G. GEYER, E.
LANDING
shales. 174-185 m: Complex of massive, dolomitic limestones. 159-174 m: Green shales, grading up-section into alternation of limestones and shales. 139-159 m: Alternation of archaeocyathan-bearing limestones, Calcaire scoriace beds, and shale layers. Shales of lower 15 m unfossiliferous. Slaty shales of unit 33 in the upper part represent F 3: Archaeocyathans, Fallotaspis longispina HUPE 1953 (type local ity and probably type stratum). 134-139 m: Green and purple shales, at the base with a lenticular massive Calcaire scoriace bed (unit 31) termed "Barre de Ksars" (compare DEBRENNE & DEIJRENNE, this volume). Shales of unit 28 represent F 2: Brevipelta chouberti GEYER 1994, Fallotaspis longa HUPE 1953, Fallotaspis planospinosa HUPE 1953 (type locality and probably type stratum), Choubertella crassioculata HUPE 1953 (type locality and type stratum), Choubertella lata HUPE 1953 (type locality and type stratum), Choubertella spinosa HUPE 1953 (type locality and type stratum), hyoliths. 117-134 m: Green shales, with purple shales at the top, alternating with Calcaire scoriacl! beds. Trilobites unknown. Archaeocyathans (DB 13) include: Retecoscinus minutus (DEIJRENNE 1959), Protopharetra gemmata (DEBRENNE 1964), Neolocu/icyathus abadiei (DEBRENNE 1959), Tumulocoscinus equiporus (DEIJRENNE 1959), Erismacoscinus marocanus (DEBRENNE 1958). 61-117 m: AIternation of thick units of greenish shales, with purple shales at the top, archaecyathan-bearing limestone beds of I to 1,5 m thickness at the base of each unit. Trilobites are found throughout the shales and are dealt with as bulk sample F I by HUPE (1959): Fallotaspis tazemmourtensis HUPE 1953 (type locality and type stratum), Fallotaspis longa HUPE 1953 (type locality and probably type stratum), Fallotaspis plana HUPE 1953, Fallotaspis plallospillosa HUPE 1953, Parared/ichia pulchella HUPE 1953 (type locality and type stratum), Parared/ichia rochi HUPE 1953 (type locality and type stratum), Parared/ichia subtransversa HUPE 1953 (type locality and type stratum), Bigotinops dangeardi HUPE 1953 (type locality and type stratum), Pruvostinoides? sp.;
& W.
HELDMAlER
archaeocyathans of DB 10 and DB 12: Mennericyathus echinus (DEBRENNE 1964), Erismacoscinus marocanus DEBRENNE 1958, Tumulocoscinus equiporus (DEBRENNE 1959), Nochoroicyathus crassus (DEBRENNE 1961), Protopharetra stipata (DEBRENNE 1964), Neolocu/icyathl/s abadiei (DEIJRENNE 1959), Agastrocyathus gregarius DEI3RENNE 1961, Retecoscinl/s minl/tus (DEBRENNE 1959). Frequently with Brevipelta chouberti GEYER 1994. 24-61 m: Bluish-green shales with intercalated thin to very thick limestone beds. Contains rare Brevipelta sp. cf. B. chouberti GEYER 1994. 0-24 m: Tiout Member. Dark to medium-grey massive limestone beds, partly oolitic, partly with oncoids. TAZE-T 0: Eofallotaspis sp., Fallotaspis? sp., Bigotinops? sp. DB 4-5: Protopharetra circl/la (DEI3RENNE 1964), Protopharetra gemmata (DEI3RENNE 1964), Erismacoscinus marocallus DEI3RENNE 1958, Erismacoscillus priml/s DEBRENNE & DEIJRENNE, Rotulldocyathus sp., Agastrocyathus gregarius DEI3RENNE 1961, Retecoscinus minutus (DEI3RENNE 1959), Nochoroicyathus crassus (DEI3RENNE 1961), Neolocu/icyathus abadiei (DEI3RENNE 1959), Aflacyathus compositus (DEI3RENNE 1961), Mellllericyathus echinus (DEBRENNE 1964).
Fossils and biostratigraphy This large number of trilobite taxa based on type material from the section indicates that the concept of HUPE's Zones I to 1II (HuPE & ABADIE 1950; HUPE, 1953) was based on the faunal succession of the Tazemmourt section. HUPE (1959) restudied the trilobite faunas and emphasized a number of levels that help refine the faunal sequence (HuPE, 1953). These levels have been listed above according to their stratigraphic position. The taxa cited by HUPE (1959) have been revised partly herein, and the new taxa listed as nomina nuda by HUPE (1959) are omitted. However, it should be noted that the majority of HUPE'S types were collections made by ABADIE, who did not record the exact sample horizon. Furthermore, a number of taxa are based on a single specimen that is unfavorably preserved, and a number of taxa require revision. As an example, the species of Pararedlichia are too poorly preserved and sparsely represented to permit recognition of their distinct characters. Hence, they cannot be
The Cambrian oflhe Moroccan Atlas regions
used in intercontinental correlations, and their assignment to Eoredlichia (which is primarily characterized by features of the thorax and pygidium that are unknown from any species of Pararedlichia) from the Yangtze Platform, as suggested by PlllOlA (1991), is questionable. Subsequent investigation of the earliest, Eofallotaspis to Fallotaspis tazemmourtensis Zone trilobites of the section suggests that their succession is well documented, but needs to be completely reported (SDZUY, 1978). These oldest trilobites belong to assemblages that are approximately coeval with those from the Tiout Member of the Igoudine Formation at Tiout (TAZE-T 0; SDZUY, 1978, unpubl.). Nevertheless, the section features a transition from the Eofallotaspis to
63
the Fallotaspis tazemmourtensis Zone. Fallotaspis fazemmourtensis is reported only from HUPE's bulk sample F I and probably occurs as high as the shale unit 20, which probably marks the top of the zone. However, the base of the zone is not yet identified, and it is thus not clear whether the base of the Amouslek Formation belongs to the Eofallotaspis Zone or the Fallotaspis tazemmourtensis Zone. The Choubertella Zone ranges up to about unit 28, but Choubertella is represently by relatively few specimens that do not permit precise identification of the limits of the biozone. The Daguinaspis Zone includes the overlying sequence, probably up to shale unit 59 (= F 9). Unit 61 yields Antatlasia hollardi, the index fossil of the overlying zone.
MayS
AMOUSLEK SECTION Setting The locality lies at the northwestern margin of the Anti-Atlas, about 32 km SW of Taroudannt on the Ait Baha map sheet (Lambert coordinates 150.6/362.7). The sequence is exposed in a few incomplete sections east and north of the nearby village, and the incompleteness of the section result from the topography and minor faults (Fig. I). The upper part of the section includes outcrops that run several hundred meters along a ridge, striking NNE-SSW, about 1 km NNE of the village of Oumsdikt ("Amouslek"; Fig. 7). The lower part of the section extends several hundred meters east of the vi llage, with parts of the sequence being well exposed at the slope northeast of the village. The name Amouslek refers to a oued close to the section and has been applied to the village, which is composed of three adjacent settlements (Fig. I). History of research Amouslek is the classic section for the "traditional" Lower Cambrian in the Anti-Atlas. The lithologic sequence was first studied by ABADIE, who made the earliest stratigraphic collection in 1950. CIiOUBERT in 1952 (CHOUBERT, 1953, 1963) collected additional fossils and measured the profile subsequently (see HUPE, 1953a). The trilobites and archaeocyathans are among the most important for the biostratigraphy of the Atlas regions, and systematic studies were published by HUPE (1953a) and DEBRENNE (1964; see also DEBRENNE & DEBRENNE, this volume). Due to its easy
accessability, the locality has been visited during numerous field excursions and gained some interest by amateur and commercial fossil collectors more than a decade ago. As a consequence, the trilobites, which were primarily collected from shale units, became rarer, and good specimens are almost absent today. Nevertheless, Amouslek was chosen as the type locality for the Amouslek, Issafen, and Asrir Formations (HOllARD, 1985), although the lalter formation is not entirely characteristic. Lithologic sequence The sequence represents a complete log from the top of the Igoudine Formation to the Tamanart Formation (Figs. 7, 8). As at Tazemmourt, the rocks generally dip NNE with an angle of about 20 0 , and the top of the section is covered by the alluvial deposits of the Souss plain. This upper part of the section forms a marked ridge north of Amouslek, which is termed the "spur of Touririne" (CIiOUBERT, 1953). Lie de vin and Igoudine Formations The section starts with the upper Lie de vin Formation, which was never studied in detail, and the lower part of the Igoudine Formation. BOUDDA et al. (1979) indicated a thickness of the Lie de vin Formation of about 1000 m and that of the Igoudine Formation of 350-400 m (probably generalized values for the northwestern Anti-Atlas). The top of the Tiout Member of the Igoudine For-
G.
64
GEYER,
E.
LANDING
&
W. I-IELDMAIER
I /-:ulla·plu\'it",1 ,jlllllllluitl
Omtlltlefllu.'piJ jre/llHm.1
Zone
NNE
Zone 1.I)CI1IW'lh
La)'Cf with
...... MJjIC~J ~nd
(N(Nk~
Hr...."..",,..,,110
I
! Atrla/lasill
j
J"'"ard,
,!
E"jaflvl
.... FB • Cl'" SO-A7. CH·05 . VCl ... F 7 CH-04 VCl'" 'U SO-A7a ~Cl A-SZ3T @,\
i
.":;.
"~ "
'0 ~N
1;'
Cl
Cl", Ff Cl ... F 5. SO-AB ""4 Cl ... F 3
t
• Cl Cl",
!
SO-A 9
-"" ""
-,>0
==:--.J
@
1')'" /,
-
~ ~
A-SZ2 CH-02
... ~CH-l Cl'U ... SO-AO. CH-l
E5E .. ..
m
c
\5 Fallotaspis tozemmourtensis Zone Eofallolaspis Zone
dolostone
~ IlEjjJ
-Btl
sandstone, quartzite
~'.~:
....
'~m till
III f1BlTI
m.w -
unconformity surface
marking distinct gap
rubbly limestone, Calcaire scoriace
tuffs.
------------------
@
V'" Cl", F 2
~
limestone
cross-bedding
volcanoclastics
shale. siltstone
calcareous nodules
... _"
intraclasts
argillaceous. silty. or slaty sandstone
archaeocyaths. bioherms
calcareous sandstone
trilobites
tuffitic sandstone
brachiopods
argillaceous coarse
small shelly fossils
sandstone conglomerate
trace fossils
pipe rock,
calcareous algae
Skolithos Quartzite
The Cambrian of the Moroccan Atlas regions
Fig. 9 (opposite). Legend of the sections illustrated in Figs.
10, 15, 16, 18, 20, 22, 24, 25, and 26.
815-851 m: Tough, greyish, purple or greenish shales, with conspicuous tulT-feldspathic layers. The resistant unit forms a notable transverse ridge in
the section. The basal portion yields cakareous septarian nodules. Upper part with small, calcitefilled, irregularly winding burrows (as above). Fossils: At the top, Cephalopy;;e Zone. F 19, Am 3, \-IA-8T: Trematobolus sp. indel., Cephalopyge notabilis GEYER 1988, f-Iamatolenus (Myopsolen us) magnus (\-IUI'E 1953), f-Iamatolenus (f-Iama/olenus) meridionalis GEYER 1990 (type locality and stratum). Lower and middle part, probably f-Iupeolenus Zone, f 18, Am 4, Am 2, GS 3: 7i'emalobolus sp. indcl., Issafeniel/a tur;;ida GEYER 1990, S/renuaeva nelimda GEYER 1990 (type locality and stratum), Pr%lemls (Pr%lenus?) sp., f-Iamatolenlls (f-Iamatolenu.l) meridionalis GEYER 1990, Acanthomicmacca sp. cf. A. coloi (HUI'E 1953), Helcionel/a sp., La/ouchel/a sp., Marocel/a sp. cf M mim GEYER 1986. Calcareous basal layers, F 17: Stromatolites, calcareous algae.
805-815 m: Alternation of greenish to purple shales and fine-grained arkosic sandstones. Asrir formation 758-805 m: Variable alternation of greyish to yellowish, arkosic sandstones, occasionally with carbonate nodules and shaly intercalations. 754-758 m: Greyish to light green shales, marlstones, and tuffaceous sandstones. Highly fossiliferous layers Iie a few meters above the base. Fauna: Probably Hupeolenus Zone. F 16, GS 5, Am I: I-lama/olen us (Hamatolenus) meridionalis GEYER 1990, Orodes schmilli GEYER 1990 (type locality and stratum), hyoliths. -680-754 m: Greenish to pale yellow sandstones, often siliceous, mostly tine-grained, locally with conglomeratic layers. With erosional lower contact with shale unit. This unit is the most resistant in the sequence and forms the lOp of the hill north of Amouslek. Issafen Formation 660--680 m: Purple shales, passing into light green shales towards the top, with Intercalated layers of rubbly limestone and tuffaceous beds. Fossils: Sectigena Zone. Whole unit assigned to
69
I' 15, SD-A3: Serrodiscus coloi HUI'E 1953, Triangulwpis zirarii zirarii (HUI'E 1953) (type locality and stratum), Pruvostinoides angustilinea/us HUPE 1953, Termiere/la sp. incert., Brevitermierel/a brevifi'ons (HUI'E 1953), La-
/ouchel/a sp. indet. Uncertain position: As I (with Sectigena? sp. A) and As 2 (Andalusiana cornu/a SDZUY 1961). HUPE (1959) distin-
guishes three levels: F 15 top, A 17: Serrodiscus coloi HUI'E 1953, Pruvostinoides angus/ilineatus HUI'E 1953. F 15 middle part: Only with ProtolemlS? (f-1upeolenus?) sp. I' 15 base (I to 4 m above the base of the unit), A 16'1', GA 17, SD-A3: Triangulaspis zirarii zimrii (HUI'E 1953) (type locality and probably type stratum), Serrodiscus coloi HUI'E 1953 (type locality and probably type stratum), undeterminable olenelloid trilobite, Pruvos/inoides angustilineatus HUI'E 1953 (type locality and probably type stratum), Brevitermierel/a brevifi-ons (HUPE 1953) (type locality and type stratum), Acanthomicmacca coloi (\-IUI'E, 1953) (type locality and probably type stratum); shales otien heavily burrowed and with traces. 495-660 m: Alternation of purple and reddish shales with greyish green shales and rubbly limestone beds of variable thickness. Tuffaceous layers occur relatively frequently, graded bedding can be seen in several horizons. Development of the Calcaires scoriaces can be seen to depend on the amount of calcareous nodules. Fauna (I' 14): only burrows are known. 377-495 m: Alternation of light green shales and beds of Calcaire scoriace. The lower part of this unit is north of Amouslek underneath the cultivated fields. Faunas: Top, SD-A4 (limestone nodules): Probably Sectigena Zone. Obolellid gen. et sp., Hebediscus sp. indet., Delgadel/a sp. cf. D souzai (DELGADO 1904), Bondonel/a sdzuyi GEYER & PALMER 1995, Nel/neria sp. inde!., EIlipsocephalacea? gen. et sp. incert.
Fig. 10 (overleaf). Detailed profile of the Asrir through ·l'amanart Formations at Amouslck, illustrating grain-size profile, color changes, sedimentologic features, paleoenvironmental interpretation, and bio- and lithostratigraphic
sequences. Thickness (left margin) in meters Irom the base of the Asrir Formation. See Fig. 10 lor legend. Based largely on unpublished data li'um W. HELDMAIER.
G. GEYER, E. LANDJNG& W. J-1ELDMAI[R
70
AM - Amouslek page 1/2
160 l FS
}bioturbation
bioturbation
150
type A type A
-Q)
.0
BFRMWPG J;""l;"l, ~
r-T"I If hi ~
2pm
alit
2
land
O~
.g
gravel.2 0,2 63'"' mm
~.£
... ~-
:0
0
various notes
Ql C
::3
The Cambrian of the Moroccan Atlas regions
71
AM - Amouslek ~p:.:a~g.:.e_=2:.:/2:..__
3 20,-_-r_ _,--
____.,-_,_-----_r---__,_-.,._-____.,
310
300 •
290
280
270
Ark
260
massive
-_""ty1: = •o r;I;;;Ic r;-r.;;Ic r;-T;l., i 2IJm
silt
2
.and
0,2
gravel.!
63· mm
- '"
.0 0
~
." ~
~ 0
0
,
various notes
c_ Oc c> E ~Q)
Q)
--'" .E
,C 0 .~
< -
(J)
r
A:
~
-
>< -
~
m
>
~
0-
J: m
::;::
~
"C>
r> z z
rn
•
Cl Cl en -< m
N
'"
r
Q)
0-
~3
'1il(J)
al r
Ol
-o
The Cambrian of the Moroccan Atlas regions
93
Le XI - Lemdad XI page 2/4
320,.-bedding (0.4)
310
} intensively g1auconitlsed
"'W{
dolo
glauconitic bels phosphatic shells
- tglauconite, onlY local oceu50)
bedding (1)
---------
}
ii/aminated
300 bedding (0.4)
290 CH, 0.5m wide
280 , , laminated
t mica bedding (1) "laminated
---------
-.c
'llaminated relief (0.5m)
270
OJ
bedding (0.41
CIl
_ _ 1Qg\.lJ
c:
_
.""",.-~----_.
260
OJ
CH, relief (1.1 m) assymetric lipples (2) lllaiminMed
bedding (0.4)
c.
o
_11.......ed ---~-----
beddirlQ (1)
250
E u.
rmica bedding (0.4)
-
CIl CIl
--------=~ -
- -
~
240
C'.
horizontal bioturbation bedding (0.5-1)
~ -OJ
•
230
lmica
...~
E
bedding (1-2)
.c ....,
•
- 22
cetS"S(P)f::=--=--::-::-::-::=--=--::-::-::-::-::':-:;--:~: -~=-
----: ~
~Rolfleckenschiefe('
tFe,iFS
rossiI hash
r", 1'" 1'"
210
too 1" 1" 1" 1"
200
bedding (1)
=
=
bedding (1-2) bedding (0.3) co
c:::>
= =
=
=
--- -- -• =
~
=
phosphatic shells
-- -,,- ---_••=-... -= ~
~-.,..- ....-_~--
=
=
.• .-
= .= =
-
~
-
-~
=
,
b
.c
.~
~GT
40
-
I"/IIIi
___
C>.
. . . . ~ «>
OW4
. _""
_
-
HCS
OW3
''''1--30
20
"h
310/
~~~ ~ ---------~""'-~~--">.
10
OW,
bioturbation
--- -
--
- - - ....
~ OWl
-
~-
---,-
oal
HCS HCS HCS
- - ..... :,M-~-~-f I I - ;;L,........,I_r-.II_,........,
.:'" ' " " " >-.0 •
..... CD Ol CD CD (7)
,g
Q.:o >.E1:l1:l A
::c >.
i';;~
•~
R UW PG r.-T.:'"1B Fr--r--1 ,....,........, i r m o l , 1m 1cl II I", 10 ..~m _I" 2 .and 0,2 orav.':i 63
- -_.
barrier
Q.
-------
«
:::l
I
c:
::J
near shore
~
o
r--~-i-
-+-:g,-~+----+--'ftu"',viaI"'·"--?'-t-+T-="§::.:.F"im
... ..!
'"(,)
b ~
-"0
0
! _
mm
various notes
cQ) .§= i:: E aradoxides" sp., echinoderm ossiclcs, Planolites. TAR-137.1: Condylopyge sp., Ornamentaspis sp. cf. 0. usitata GEYER 1990, "ParadoxMes" sp. TAR-135.0: Ornamentaspis sp. indct, "Paradoxides" sp. indct, hyoliths. TAR-133.6: Ornamentaspis sp. indet TAR-133.4: Cf. Ornamentaspis destombesi GEYER 1990, "Paradoxides" sp. TAR-132.2: Ornamentaspis destombesi GEYER 1990, "Paradoxides"
sp. TAR-132.1: Condylopyge sp., Ornamentaspis sp. cf. 0. usitata GEYER 1990, "Paradoxides" sp., "Parasolenopleura" sp., Agraulos sp.
TAR-13I.5-132.0: Trilobites. TAR-130.5: "Paradoxides" sp. TAR-I 30.4: Ornamentaspis destombesi GEYER 1990. TAR-130.0: "Paradoxides"sp. TAR·129.8: Ornamentaspis sp. cf. 0. usitata GEYER 1990. TAR-129.7: Ornamentaspis? sp. TAR-129.0: "Paradoxides" sp., Ornamentaspis desfombesi
GEYER
1990. TAR-128.8: Ornamentaspis destombesi GEYER 1990, Ornamentasp;s sp. cf. 0. usitata GEYER 1990, "Paradoxides" sp., Agraulos sp., undcl. echinoderms, carpoid fragmcnts
(probable einelans). TAR-128.5: Ornamentaspis sp. cf. 0. IIsitata GEYER 1990. TAR-126.5: Ornamentaspis sp. cf. 0. IIsitata GEYER 1990. TAR-126.3: Ornamentaspis sp. cf. 0. destombesi GEYER 1990. TAR-125-128.5: Condylopyge sp., Ornamenfaspis sp. cf. 0. lIsitata GEYER 1990, Ornamentaspis destombes; GEYER 1990, "Paradoxides" sp., hyoliths, cchinodcnn ossiclcs. TAR-123: Planoliles. TAR-122.5: Ornamenlaspis sp. cf. 0. IIsitata GEYER 1990, Kingaspidoides sp. cf. K. brevi/rons (l-IuPE 1953), Acadoparadoxides sp. TAR-121.5: Cf. Ornamentaspis destombesi GEYER 1990.
TAR-I2I: Trilobites. TAR-I 19.9-120.2: Planolites (large). TAR-I 18.5-1 19: Ornamentaspis sp. cf. 0. destombesi GEYER 1990, "Paradoxides" sp., "Solenopleura" sp., hyoliths, Planolites. TAR-II7.1: Ornamentaspis destombesi GEYER 1990. TAR-I 15.3-117: Planolites.
TAR-I 15.2: Large traces. TAR-109. 7-115: Ornamentaspis sp., "Paradoxides" sp., hyoliths.
G. GEYER, E. LANDING & W. HELDMAIER
116
TAR-I09,?: Omamentaspis sp. cf. 0. sifalQ GEYER 1990, OrnamentQspis deSlombesi GEYER 1990, "Paradoxides" sp. indct.
Skrejaspis sp., "Parasolenopleura" sp., Planolites. TAR-l 09.6: Ornamenfaspis sp. cf. 0. deSlombesi GEYER 1990. TAR-! 09.5: Ornamentaspis destombesi GEYER 1990, "Paradoxides"
sp. TAR-I 09.4: Ornamentaspis deSfombesi GEYER 1990, "Paradoxides"
sp. TAR-109.3: Planolites. TAR-109.2: Ornamentaspis destombesi
GEYER
1990, "Paradoxides"
sp. TAR-I 07 .0: "Paradaxides" sp. TAR-I06.9: Trilobites indct., "Paradoxides"sp. TAR-IOS.S: Ornamentaspis sp. cf. 0. sitata GEYER 1990. TAR-lOS: Ornamenlaspis sp. cf. 0. sitota GEYER 1990. TAR-I02.4: Trilobite sclerites. TAR-I 01.6: "Paradaxides" sp.
TAR-100.3-100.6: Accumulations of trilobite scicritcs. TAR-98-1 00: Planoliles. TAR-96.3-98: Ornamentaspis sp. cf. 0. sitata GEYER 1990. TAR-94.8: Burrows. TAR-93.8: Ornamentaspis destombesi GEYER 1990. "Paradoxides" sp., hyolilhs. TAR-92.1: Trilobite fragments. TAR-91.8-92.05: Peronopsis sp., Condylopyge sp., Ornamentaspis usi/ata GEYER 1990, Acadoparadoxides sp. cf. A. briaraeus GEYER 1993, "Parasolenopleura" sp., hyoliths, echmoderm ossicles, "Planolites" isp. TAR-91.7: Acadoparadoxides briareus GEYER 1993. TAR-91.5: Aeadoparadoxides briareus GEYER 1993. TAR-90.0: Trilobite sclerites. TAR-84.5: Acadoparadoxides briareus GEYER 1993. TAR-83.1: Ornamentaspis sp. cf. 0. destombesi GEYER 1990. TAR-83.0: Ornamentaspis sp. cf. 0. destombesi GEYER 1990. TAR-82.9: Ptychopariid gen. et sp. ineert. TAR-79.3: Condylopyge sp., Ornamentaspis sp. cf. 0. destombesi GEYER 1990, Ornamentaspis sp. cf. 0. angustigena GEYER 1990, Acadoparadoxides briareus GEYER 1993. TAR-77 .8-78.1: Lingulids, Condylopyge sp., Peronopsis sp., Ornamentaspis sp. cf. 0. destombesi GEYER 1990, Ornamentaspis usitata GEYER 1990, Kingaspidoides laews GEYER 1990, Aeadoparadoxides briareus GEYER 1993, "Parasolenopleura" sp., Yuehsienszella? n. sp., Skrejaspis sp., hyoliths, echinoderm debris. TAR-75: Condylopyge sp., Cephalopyge "otabilis GEYER 1988, Kingm,pidoides sp. cf. K. brevifrons (J-IUPE 1953), Ornamentaspis sp. cf. 0. usitata GEYER 1990, Acadoparadoxides briaraeus GEYER 1993, COfloeoryphe (Parabailiella?) sp., Parasolenopleura sp., echinoderm hash. TAR-74.5-77.0: Upper briaraeus bed, Jbel Wawrmast Formation, Peronopsis sp., Condylopyge sp., Kingaspidoides sp. cf. K. laetus GEYER 1990, Ornamentaspis usi/ata GEYER 1990, Ornamentaspis sp. cf. 0. destombesi GEYER 1990, Acadoparadoxides briareus GEYER 1993, "Parasolenoplellra" sp., Yuehsienszella? n. sp., hyoliths, echinoderm ossicles, "Planolites". TAR-63-64.5: Lower briaraeus bed. Cephalopyge notabUis GEYER 1988, Ornamentaspis sp. cf. 0. destombesi GEYER 1990, Ornamentaspis sp. cf. 0. usitata GEYER 1990, Ornamentaspis angusligena GEYER 1990, Hamatolenus (II.) sp. cf. /-I. (/-I.) maroccanllS (NELTNER 1938), Aeadoparadoxides briarells GEYER 1993, Yllehsienszella? n. sp., "Parasolenopleura" sp., cchinodcrrn ossicles, hyoliths, Planolites. TAR-60.2: Teleslo bed, Tremaloboilis splendidlls GEYER & MERGL, 1995, Cambropallas teleslo GEYER t 993, Ornamentaspis sp. cf. 0. deslOmbesi GEYER 1990, Omamentaspis angustigena GEYER 1990, Acadoparadoxides briareus GEYER 1993, hyo-
Iiths.
TAR-52-54: Trematobol"s splendid"s GEYER & MERGL, 1995, Ornamentaspis angustigena GEYER 1990, "Paradoxides" sp. Breche
a Micmacca Member
TAR-51.1: Trematobol"s splendid/IS GEYER & MERGL 1995, Condylopyge sp., Cephalopyge notabilis GEYER 1988, Kingaspidoides sp. cr. K. laetus GEYER 1990, Kingaspidoides sp. cf. K. brevifrons (HUPE 1953), Kingaspis sp. cf. K. sarhroensis GEYER 1990, Ornamentaspis angtlstigena GEYER 1990, Protolenus (Protolenus) sp., Latoucheia (Latoucheia) epichara glabra GEYER 1990. TAR-49.2: Trematobolus splendidus GEYER & MERGL, 1995, Kingaspidoides sp. TAR-48.5: Cephalopyge notabilis GEYER 1988, Kingaspidoides neglectus GEYER 1990, "Paradoxides" sp., hyoliths. TAR-47.2-47.8: Accumulations of trilobite sclerites. TAR-43.3: Trilobite sclerites. TAR-35.3: Trematobolus splendidus,. TAR-35.0: Trematabal"s sp. cf. 7: splendid"s GEYER & MERGL 1995. TAR-32.0: Kingaspidoides laellts GEYER 1990. TAR-31.7: Various trilobites, Trematobolus sp. cf. T splendidus GEYER & MERGL 1995. TAR-30: Scleritcs of various trilobites. TAR·28.4: Sclerites of various trilobites, Kingaspidoides neglecllls GEYER 1990, echinoderm ossicles. TAR-28.0: Trematobolus sp. cf. T. splendidus GEYER & MERGL 1995. TAR-26.6: "Paradoxides" sp. TAR--24-25.5: Trematobol"s splendid"s GEYER & MERGL 1995, Cambropallas telesto GEYER 1993, Ornamentaspis sp. arT. 0. usilata GEYER 1990, Omamentaspis lIsitata GEYER 1990, "Paradoxides" sp., Parasolenopleura sp. indcl, echinoderm ossicles. TAR-24.1: "Paradoxides" sp. TAR-23: Planolites. TAR-22.I: Cambropallas telesto GEYER 1993. TAR-20: Ornamentaspis sp., "Paradoxides" sp. TAR-18.5-19: Planolites. TAR-17.6: Trilobite scierites. TAR-16.8: Trematobolus sp. cf. 7: splendidus GEYER & MERGL 1995, Protolenus (Protolenus) sp., "Paradoxides" sp. TAR-14.9: "Paradoxides" sp. TAR-14.6: Trematobolus splendidus GEYER & MERGL 1995, Pelagiel/a sp. cf. P. atlasensis GEYER 1986, Kingaspidoides neglectus GEYER 1990, Laloucheia (Latoucheia) epichara GEYER 1990, Protolenus (Protolenus) interseriptus GEYER 1990, "Paradoxides" sp. TAR-14.5: Branched Planalites. TAR-14'): Kingaspidoides negleetus GEYER 1990. TAR-14.2: Trilobite sclerites. TAR-14.t: Trematobolus sp. cf. T splendidus GEYER & MERGL 1995. TAR-13.4: Ornamentaspissp. indel. TAR-10.6: Trematobolus sp. cf. T. splendidus GEYER & MERGL 1995. TAR-IO.5: Trematobolus sp. cf. T. splendidus GEYER & MERGL 1995, Kingaspidoides sp., Kingaspidoides negleetus GEYER 1990, Protolenus? sp., "Paradoxides" sp. TAR· I0.2: Kingaspidoides sp. cf. K. laetus GEYER t 990. TAR-IO.O: Planalites. TAR-9.6: Trilobite hash. TAR-6.4: Planolites. TAR-6.1: Teichichnus? sp. TAR-6.0: Trilobite hash, stromatolite crust on top.
The Cambrian of the Moroccan Atlas regions
TAR-5.9: "Paradoxides" sp.
TAR-4,O: Planalites (large). TAR-3.25: "Paradaxides" sp. TAR-2.2-2.5: Kingaspidoides sp. ef. K. laetus GEYER 1990, Plano!ifes.
TAR-2.1: Trematobolus splendidus GEYER & MERGL 1995, trilobite hash. TAR- t .9-2,0: Kingaspidoides negleetlJs GEYER 1990, "Paradoxides" sp., Heleionel/a? sp., Pelagiel/a sp. cf. P. atlasensis GEYER
1986, hyolith opercula. TAR-1.9: Strong burrow mottling.
117
GEYER 1988, Kingaspidoides neglectlls GEYER 1990, Kiflgaspidoides? sp. indet, Protolenlls (Hllpeolenlis) hupei GEYER 1990, Protolenus (Hupeolenus) sp. cf. P. (H.) termierelloides GEYER 1990, Latollcheia (Latouc!reia) epiehara epic/rara GEYER 1990, Latoucheia (Pselldolenus) sp. cf. L. (1'.) ourikaensis (HUPE 1953), "Paradoxides" sp., Aeanrhomicmacca n. sp. TAR-0.65-2.0: Tremarobolus splendidus GEYER & MERGL 1995, Kingaspidoides negleetlJs GEYER 1990, "Paradoxides" sp. TAR-0.60-0.65: Trematobolus splendidus GEYER & MERGL 1995,
Condylopyge sp., Cephalopyge norabilis GEYER 1988, King-
TAR-I: Cambropal/as telesto GEYER 1993, Kingaspidoides sp. indel, Ornamenraspis sp. cf. O. Ilsitata GEYER 1990. TAR-0.7: Trematoboills splendidus GEYER & MERGL 1995, "Israelaria" sp. cf. "I." simplicissima (MERGL 1982), Marocella sp. cf. M. mira GEYER 1986, ef. Cephalopyge norabilis
aspidoides negleetus GEYER 1990, Protolellus (Hllpeolelllis) dimarginatus GEYER 1990, Profolenlis (f1upeolenus) lermierel/oides GEYER 1990, cf. Gigoutel/a atlasensis HUPE 1953, Aeanthomiemaeca n. sp. A, Protoleninae n. gen. el n. sp., "Paradoxides" sp.
Acknowledgments We arc indebted to E. BERNEKER for results of his investigations and to K. SDZUY for unpublished data. E. L1NAN and R. GOZALO supplied data on fossil occurrenceS from observations made during the field workshop, which is gratefully acknowledged. Field work of G. G. and W. H. was made possible by a grant of the Deutsche Forschungsgemeinschaft DFG (grant Ge 549/9-1) and financial support of the Graduierten-Kolleg of the Faculty of Geosciences,
Bayerischc Julius-Maximilians-Universit3t WOrzburg. G. G. further acknowledges support by a Heisenberg grant of the Deutsche Forschungsgemeinschaft. E. L. acknowledges field and laboratory assistance from the National Science Foundation (grant EAR 94-15773). Special thanks arc due to H. SCHIRM, WOrzburg, for assistance with photography and repros, and to BINARDESIGN, WOrzburg, for permission to usc their computer equipment.
References BONDON, J. & NELTNER, L. 1933. Sur la serie cambricnne des plateux de Draa (Sud Marocain) et la presence du Georgien
dans eelle serie. - C. R. Aead. Sci. Paris CXCVII: 170-172; Paris.
BOUDOA, A. 1968. Zur geologischen Kartierung I : 25000 im Gebiet von Ounein (Massif ancien du Haul-Atlas, Marokko). -
Master's ti,es is, Pal~ont. Inst. Univ. WUrzburg: 52 p., 35 figs., 2 pis.; WUrzburg. -Iunpubl.]. BoUODA,
A. & ClIOUBERT, G. 1972. Sur la limite infcrieur du Cam-
brien au Maroc. - C. R. Aead. Sci., Paris, (D) 275: 5-8; Paris. BOUDOA, A., CIIOUDERT, G. & FAURE-MuRIT, A. 1975. Coupe geologique de l'Ounein. Description lithologique. - Reunion Lim. Cambrien-Precarnbrien, Agadir-Rabat, 1975, Doc. V
A+B: 14 p., fig.; Rabat. -Iunpubl.]. BOUOOA, A., CIIOUDERT, G. & FAURE-MURET, A. 1979. Essai de Stratigraphie de la Couverturc sedimentaire de J'Anti-Atlas: Adoudounien - Cambrico Infcricur. - Notes Mem. Servo geol Maroc 271: 96 p., 20 figs.; Rabat. BRABERS, P. M. (1988): A plate tectonic model for the Panarrican Orogeny in the Anti-Atlas. Morocco. - In: JACOUSI-IAGEN, V. 1-1. (cd.). The Atlas System of Morocco. Studies on its Geodynamic Evolution. Lecture NOles in Earth Sciences 15: 6180, 8 fig.; Berlin, lIeidelberg, New York, London, Paris,
Tokyo (Springer). CtIOUBERT, G. 1952. Ilistoire geologique du do maine de l'Anti·Atlas.• In: CIIOUBERT. G. & MAR~AIS, J. Geologie du Maroc.
las. Introduction stratigraphique. - In: HUPE, P. Contribulion a I'etude du Cambrieo inferieur et du Precambricn III de l'Anti-
Atlas marocain. Notes Mem. Servo geol. Maroc 103: 17-39,4 figs.; BagnoletiSeine. - I" 1952"]. CIIOUDERT, G. 1963. Histoire geologique du Precarnbrien de l'AntiAtlas. Tome I. - Noles Mem. Servo geol. Maroc 162: 352 p., 33 figs., 81 phot., 5 maps, 7 color maps; Rabat. CIIOUDERT, G., BOUDOA, A. & FAURE-MuRIT, A. 1975. Essai de straligraphie de la couverturc sedimentaire de l'Anli-Allas: Adoudounien - Cambrico infericur. - Reunion Lim. Carn-
brien-Precarnbrien, Agadir-Rabat, 1975, Doc. IA+IB: 57 p., II figs.; Rabat. -Iunpubl.]. CIIOUDERT, G. & FAURE-MuRIT, A. (et aI., 1970): Livret-guide de I'excursion Anti-Atlas occidental cl central. - Colloque inlernational sur Ics correlations du Precambricn. Agadir - Rabat -
3-23 mai 1970. Notes Mem. Servo geol. Maroc 229: 259 S., 49 figs.; Rabat. .
COMPSTON, W.,
WILLIAMS,
I. 5., KIRSIlVINK, J. L., ZHANG ZICHAO &
MA GUOGAN 1992. Zircon U-Pb ages from the Early Cambrian time-scale. - J. Geol. Soc. London 149: 171-184,10 figs.,5 labs.; London. COMPSTON, W., WILLIAMS, I. S., RsES, A., KIRSHVINK, 1. & ZHANG ZJClIAO (1990): Zircon U-Pb ages relevanl to lhe Cambrian numerical lime-scale. - Seventh International Conference on Geochronology, Cosmochronology, and Isolope Geology,
Canberra, 24-29 September 1990, Abstracts 27: 21; Can-
Xlxe Congrcs Geol. Intern., Alger 1952, Monogr. reg., Ser. 3, Maroc, 6: 77-194, 16 maps; Alger.
DEBRENNE, F. 1958. Sur quelques Archaeocyatha du Jebel Taissa
CtIOUDERT, G. 1953. Lc Preeambrien III etle Georgien de l'Anti-At-
(Anti-Atlas occidental). - NOles Servo geol. Maroc 16, 143:
berra.
118
G. GEYER,
E.
LANDING
59-73, 2 figs., 2 pis.; Rabat. DEBRENNE, F. 1959. Un nouveau genre d'Archaeocyatha du Cam-
brien marocain. - C. R. Soc. geol. France 1959 (I): 14-16, I fig.; Paris. DEBRENNE. F. 1960a. Archaeocyatha des lentilles calcaires de Tazemmourt (Anti-Alias). - Notes Mcm. Servo geol. Maroc 18 (147): 7-26, I fig., pis. I-V; Rabat. OEnRENNE, F. 1960b. Deux nouveaux genre d'Archaeocyatha du Cambricn marocain. - C. R. somm. Soc. geo!. France 5: 118,
2 figs.; Paris. Nouvelles donnees sur la faune d'Archacocyatha du Jbcl Taissa (Anti-Atlas occidental). Notes Servo geol. Maroc 20,152: 7-37, pis. i-VI; Rabat
DEBRENNE,
F.
1961.
DEB RENNE, F. 1964. Archaeocyalha. Contribution a I'etude des
faunes cambriennes du Maroc, de Sardaignc ct de France. Notes Mem. Servo geol. Maroc 179: 371 p., 52 pis.; Rabat
F. 1975. Formations organogenes du Cambricn infcricur du Maroc. - Akad. Nauk SSSR, Trudy Inst. gcol. gcofiz. 202: 19-24; Novosibirsk (Nauka).
DEBRENNE,
DEB RENNE, F. 1992. Archaeocyatha du Maroc: Essai de synthese. Geologie Mediterraneenne, XVII [for 1990J (3-4): 213-227, I fig., 3 tabs.; Aix-en-Provcnce. F. & DEBRENNE, M. 1975. Age des premieres et dernicres faunes d'Archaeocyathes du Cambrien infcrieur du Maroc. - Rcun. Gr. Trav. Limitc Prccambrien-Cambrien, Marokko, 23. Okt. - 2. Nov. 1975: 7 p. - [unpubl.].
DEBRENNE,
DEBRENNE, F. & DEBRENNE, M. 1976. Arehaeocyathid fauna of the lowest fossiliferous levels of Tiout (Lower Cambrian Southern Morocco). - Reun. Gr. Trav. Limite Precamb.Cambrien Maroc, Mars-Avril 1976, C. R. activitc: 22 p., pIs. I-IV; Rabat - [un pub I.]. DEB RENNE, F. & DEB RENNE, M. 1978. Archaeocyathid fauna of the lowest fossilifcrous levels of Tiout (Lower Cambrian Southern Morocco). - Geol. Mag. 115 (2): 1101-119, 3 labs., pis. 1-4; London. DEB RENNE, F., DEBRENNE, M. & FAuRE-MuRET, A. 1992. Faune d'ArchCocyathes de l'Anti-Atlas occidental (bordures Nord et Sud) et du Haut Atlas occidental. Cambrien inferieur, Maroc. - Geologic Mediterraneennc XVII (3-4): 177-211, 8 figs., pis. I-IV; Aix-en-Provence. DEB RENNE, F. & DEDRENNE, M. this volume. Archaeocyaths of the Lower Cambrian of Morocco. - Beringeria, Special issue 2: 121-145,3 figs., 4 tabs., 4 pis.; WOr£burg. DESTOMDES, J., 1-lolLARD, H. & WrLLEFERT, S. 1985. Lower Palaeozoic Rocks of Morocco. - In: HOllAND, C. H. (cd.). Lower Palaeozoic Rocks of the World. Vol. 4. Lowcr Palacozoic of north-western and west central Africa: 91-336, 68 figs.; Chichester, New York, Brisbane, Toronto, Singapore (John Wiley & Sons). FRITZ, W. H. 1972. Lower Cambrian trilobites from the SeJ...--wi Fonnation type section, Mackenzie Mountains, northwestern Canada. - Geol. Surv. Canada, Bull. 212: 58 p., 3 figs., 20 pis.; Ottawa. GEYER, G. 1983. Biostratigraphische und systematisch-paHlontologische Untersuchungen 1m Grenzbereich Unter-/ Mittelkambrium von Marokko. - Ph. D. diss., PaHiont. Inst. Univ. WOr£burg: 229 p., 36 figs., 4 labs., 19 pis.; WOrzburg.[unpubl.]. GEYER, G. 1986. Mittelkambrische Mol1usken aus Marokko und Spanien. - Senckenberg. lethaea 67 (1/4): 55-118, 6 figs., I tab., 6 pis.; Frankfurt a. M.
& W. HELDMAIER
GEYER. G. 1988a. Agnostida aus dem hOheren Unterkambrium und dem Mittelkambrium von Marokko. Teil I: Agnostina. - N. lb. Geol. Pal~ont Mh. 1988 (3): 141-152,12 figs.; Sluttgart. GEYER, G. 1988b. Agnostida aus dem hOheren Unterkambrium und dem Mittelkambrium von Marokko. Teil 2: Eodiscina. - N. lb. Geol. PaiMent. Abh. 177 (I): 93-133,112 figs.; Stuttgart. GEYER, G. 1989a. Late Precambrian to early Middle Cambrian lithostratigraphy of southern Morocco. - Deringeria I: 115-143, 7 figs., I tab.; WOrzburg. GEYER, G. 1989b. "Supercycles" and complex cyclicity in the Late Precambrian and Cambrian of Morocco. - 28th Intern. Geol. Congr., Washington, Abstracts 3: 3-470; Washington, D. C. GEYER, G. 1990a. Revised Lower to lower Middle Cambrian bioslratigraphy of Morocco. - Newsl. Slraligr. 22 (2/3): 53-70,2 figs., 2 pis.; Berlin, Stuttgart. GEYER, G. 1990b. Proposal of formal lithostratigraphical units for the Terminal Proterozoic to early Middle Cambrian of soulllcrn Morocco. - Newsl. Slratigr. 22 (2/3): 87-109,2 figs.; Berlin, Stuttgart. GEYER, G. 1990c. Correlation along the LowerlMiddle Cambrian boundary - a puzzling story with an elusory end? - In: REPINA, L. N. & ZHURAVlEV, A. Yu. (cds.) Tretij mezhdunarodnyj simpozium po kembrijskoj sisteme. 1-9 avgusta 1990 g., SSSR, g. Novosibirsk. Tezisy dokladov: 100-102, I Tab.; Novosibirsk. GEYER, G. (l990d): Die marokkanischen Ellipsoccphalidae (Trilobita: Rcdlichiida). - Beringeria 3: 363 p., 69 figs., 9 labs., 56 pis.; WOrzburg. GEYER, G. 1993. The giant Cambrian trilobites of Morocco. - Beringeria 8: 71-107,4 figs., II pis.; WOrzburg. GEYER, G. 1994a. An enigmatic bilateral fossil from the Lower Cambrian of Morocco. - I. Palcont. 68 (4): 710-716, 2 figs.; Tulsa, Okla.
GEVER, G. 1994b. A new obolellid brachiopod from the Lower Cambrian of Morocco. - I. Paleont. 68 (5): 995-1002,4 figs.; Tulsa, Okla. GEYER, G. I994c. Cambrian corynexochid trilobites from Morocco. - I. I'aleont. 68 (6): 1306-1320,9 figs.; Tulsa, Okla. GEYER, G. & MERGl, M. 1995. Mediterranean representatives of the obolcllid Trematobollis (Brachiopoda) and a review of the genus. - Pal~ont Z. 69 (1/2): 179-209, 14 figs.; Stuttgart. GEYER, G. & PALMER. A. R. 1995. Neltneriidac and I-Iolmiidae (Trilobita) from Morocco and the problem of Early Cambrian intercontinental correlation. - J. I)aleont. 69 (3): 459-474, 7 figs.; Tulsa, Okla. HOLLARD, H. 1985. Precambrian-Cambrian Boundary and Lower Cambrian. - In: DESTOMBES, J., )-IOlLARD, H. & WIllEFERT, S.. Lower Palaeozoic Rocks of Morocco. In: HOLLAND, C. H. (cd.). Lower Palaeozoic Rocks of the World, Vol. 4: Lower Palaeozoic of north-western and west central Africa: 101157, figs. 5-28, pis. 1-4; Chichester, New York, Brisbane, Toronto, Singapore (J. Wiley & Sons). 1-luPE, P. 1953. Contribution a I'ctudc du Cambrien inferieur ct du Precambrien III de l'Anti-Atlas marocain. - Notes Mem. Servo geol. Maroc 103: 402 p., 99 figs., 4 tabs., pis. I-XXIV; BagnoleVSeine. - [" 1952"]. 1-luPE. P. 1959. Nouvelle contribution a I'etude du Cambricn marocain. - These Sci. Fac. Sci. Univ. Paris: 447 p., 12+5 figs., 3 Karten, pis. A-W, 1-10, IObis, 11-32; Paris. - [unpubl.j. HUPE,
P. & ABADIE, J. (1950): Sur I'existence de Trilobites du Cambrien infcrieur asiatique dans l'Anti-Atlas marocain. - C. R.
The Cambrian of the Moroccan Atlas regions
Acad. Sci., Paris, 230: 2112-2113; Paris. KIRSliVlNK, J. L., MAGARlTL, M., RIPPERDAN, R. L. & ZUURAVLEV, A. Yu. 199 I. The Precambrian/Cambrian boundary: Magnetostratigraphy and carbon isotopes resolve correlation problems between Siberia, Morocco, and South China. - GSA today I (4): 69-71, 87, 9 1,4 figs.; Boulder, Colo. LANDING, E. & BRETT, C. E. 1987. Trace fossils and regional significance of a Middle Devonian (Givetian) disconformity in southwestern Ontario. - J. Palcont. 61 (2): 205-230, 10 figs., I tab.; Tulsa, Okla. LAHIAM, A. J. 1990. The Precambrian/Cambrian transition in Morocco. - Ph. D. thesis, University of Wales, Cardiff: 240 p.; Cardiff. -(unpublished]. LATIIAM, A. & RIDING, R. 1990. Fossil evidence for the location of the Precambrian/Cambrian boundary in Morocco. - Nature 344 (6268): 752-754, 2 figs.; London. L1NAN, E. & GOZALO, R. 1986. Trilobites del Cambrico inferior y medio de Murero (Cordillera Iberica). - Mem. Mus. Paleonl. Univ. de Zaragoza 2: 104 p., 26 figs., 37 pis.; Zaragoza. LIN-AN, E. & SOZUY, K. 1978. A trilobite from the Lower Cambrian of C6rdoba (Spain) and its stratigraphical significance. Scnckenberg. lethaea 59 (4-6): 378-399, 2 figs., I pI.; Frankfurt a. M.
119
SCUMITT, M. 1979a. The section of Tiout (Precambrian/Cambrian boundary beds, Anti-Atlas. Morocco): Stromatolites and their biostratigraphy. - Arb. Palaont. Inst. WUrlburg 2: 188 p., 44 figs., 23 pis.; WUrzburg. - [unpubl.]. SCHMm, M. 1979b. New stromatolites from the Late Precambrian of the Anti-Atlas and from the Lower Cambrian of the I-ligh Alias, Morocco. - Senckenberg. lethaea 60 (1/3): 39-49, 7 figs., 2 pis.; Frankfurt a. M. SCHMI'IT, M. O. & MONNINGER, W. E. W. 1977. Stromatolites and thrombolites in Precambrian/Cambrian boundary beds of the Anti-Atlas, Morocco: Preliminary results. - In: FLOGEL, E. (cd.). Fossil Algae: 80-85, 2 pis.; Berlin, Heidelberg (Springer- Verlag). SOZUY, K. 1961. Das Kambrium Spaniens. Teil II: Trilobiten. I. Abschnitt. - Akad. Wiss. Lit. Mainz, Abh. math.-naturwiss. KI., 1961 (7): 499-594 (217-312), figs. 1-23, pis. I-XV; Wiesbaden. SDZUY, K. 1978. The Precambrian-Cambrian boundary beds in Morocco (Preliminary Report). - Geol. Mag. 115 (2): 83-94, 6 figs., I pI.; Cambridge. SDZUY, K. 1981. Der Beginn des Phanerozoikums - PaHlobiologische und stratigraphische Probleme. - Natur und Museum III (II): 390-399, 20 figs.; Frankfurt a. M.
MAGARITL, M., KIRSUVINK, J. L., LATI-IAM, A. J.• ZUURAVLEV, A. Yu. & ROZANOV, A. Yu. 1991. Precambrian/Cambrian boundary problem: Carbon isotope correlations for Vendian and Tommotian time between Siberia and Morocco. - Geology 19 (8): 847-850,2 figs.; Boulder, Colo.
SDZUY, K. & GEYER, G. 1988. The base of the Cambrian in Morocco. - In: JACODSHAGEN, V. H. (cd.). The Atlas System of Morocco. Studies on its Geodynamic Evolution. Lecture Notes in Earth Sciences 15: 91-106, I fig.; Berlin, Heidelberg, New York, London, Paris, Tokyo (Springer).
MONNINGER, W. 1979. The section of Tiout (Precambrian/Cambrian boundary beds, Anti-Atlas, Morocco): An environmental model. - Arb. Palaont. Inst. WUrzburg I: 289 p., 49 figs., 32 tabs., 22 pis.; WUrlburg. - [unpubl.].
SIEGERT, R. 1986. Die klastischen Serien an der Wende vom Unterzum Mittelkambrium im Anti-Atlas (Marokko). - Ph. D. diss., Naturwiss. Fak. Univ. Erlangen: 179 + LJ pp., JOI fig., tabs. I-XXVII, pis. I-II; Erlangcn. - [un pub I.].
MONNINGER, W. & SCHMITT, M. 1975. The section of Tiout: lithology and algal structures. - Reun. Gr. Trav. Limite Precambricn/Cambrien, Agadir-Rabat, 23. Okt.-2. Nov. 1975: 8 p.; Rabat. -[unpubl.].
TUCKER, M. E. 1986a. Carbon isotope excursions in Precambrian/Cambrian boundary beds, Morocco. - Nature 319: 4850,2 figs.; London.
PllLOlA, G. L. (1991): Trilobites du Cambricn infericur du SW de la Sardaigne, Italic. - Palaeontographia Italica. Raccolta Monogr. palcont. LXXVIII: 174 p., 56 figs., 32 pis.; I'isa. RENNER, E. 1994. Isotopic correlations of Precambrian/Cambrian boundary sections from the Anti-Atlas/Morocco. - Final Meeting of I.G.C.P. Project 293 "Geochemical Event Markers in the Phaneroloic", Erlangen September 26-28, 1994. Abstracts and Guide Book. Erlanger geol. Abh. 122: 48; Erlangen.
TUCKER, M. E. 1986b. Peritidal transgressive oolite cycles, Lower Cambrian, Morocco. - Sediments down-under. 12th International Sedimentological Congress, Canberra, 24-30 August 1986, Abstracts: 307, I fig.; Canberra. TUCKER, M. E. 1989. Carbon isotopes and Precambrian-Cambrian boundary geology, South Auslralia: ocean basin fonnation. seawater chemistry and organic evolution. - Terra Nova 1: 573-582,9 figs.; Oxford.
ROZANOV, A. Yu. & DEDRENNE, F. (1974): Age of archaeocyathid assemblages. - Amer. J. Sci. 274: 833-848, 7 figs.; New I-laven, Conn.
VAN LooY, J. 1985. I-let kaartblad Tazenakht 1/100.000, Anti-alias, Marokko. Kartering, Lithostratigrafie, Biostratigrafie van Precambrium tot Tremadoc. - Proefschrift Fac. Wetenschappen, Kath. Univ. Leuven: 198 p., figs., 9 pis.; Leuven. [unpubl.].
SCHMITT, M. 1978. Stromatolites from the Tiout section. Precambrian-Cambrian boundary beds, Anti-Atlas, Morocco. - Geol. Mag. Special issue 115 (2): 95-99, 3 figs., I pI.; Cambridge.
WESTERGARD, A. H. 1953. Non-agnostidean trilobites of the Middle Cambrian of Sweden. III. - Sver. geol. Unders. (C) 526: 58 p.,8 pis; Stockholm.
