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Integrated brachiopod-based bioevents and sequence-stratigraphic framework for a Late Ordovician subpolar platform, eastern Anti-Atlas, Morocco

Published online by Cambridge University Press:  21 October 2014

JORGE COLMENAR  and
J. JAVIER ÁLVARO
JORGE COLMENAR*
Affiliation:
Área de Paleontología, Departamento Ciencias de la Tierra, Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain
J. JAVIER ÁLVARO
Affiliation:
Centro de Astrobiología (CSIC/INTA), Ctra. de Torrejón a Ajalvir km 4, 28850 Torrejón de Ardoz, Spain
*
†Author for correspondence: [email protected]
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Abstract

The Upper Ordovician (Katian–Hirnantian) brachiopods of Tafilalt, eastern Anti-Atlas, are locally abundant, diverse and well preserved, providing a near-continuous record of faunal change on a high-latitude siliciclastic-dominated platform. A chronostratigraphic framework, based on brachiopod distribution and preservation in shell accumulation events and integrated with sequence stratigraphy, has been generated for the Katian interval, which has allowed correlation with the chitinozoan-based chronostratigraphic and sequence-stratigraphic framework erected for the central Anti-Atlas. In Tafilalt, two Katian (transgressive–regressive) composite depositional sequences, c. 60 and 170 m thick and related to third-order fluctuations in sea level, were unaffected by Hirnantian glaciogenic erosion. They were deposited on a mixed platform with a bryonoderm association dominated by brachiopods, bryozoans and echinoderms. Brachiopods developed in high-energy inner shelf areas, whereas bryozoans (mainly trepostomates and fenestrates) and pelmatozoans (cystoids and crinoids) dominated in low-energy outer shelf areas. Brachiopod accumulations mark distinct event surfaces, such as lag and event concentrations, hydraulic simple and composite concentrations related to transgressive surfaces, and hiatal condensed concentrations marking maximum flooding surfaces. The taphonomic condensation displayed by the Hirnantian Alnif Member, which onlaps the erosive base of glaciogenic tunnel channels, is explained as reworking and resedimentation of allochthonous, robust, biogenic hard parts sourced from the underlying (Katian) Ktaoua Group.

Keywords

bryonodermmixed platformunconformitydiachroneityglaciationGondwana
Type
Original Articles
Information
Geological Magazine , Volume 152 , Issue 4 , July 2015 , pp. 603 - 620
Copyright
Copyright © Cambridge University Press 2014 

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References

Álvaro, J. J., Vennin, E., Villas, E., Destombes, J. & Vizcaïno, D. 2004. Hirnantian valley-glacier sedimentation in the eastern Anti-Atlas, Morocco. Erlanger Geologische Abhandlungen 5, 18–9.Google Scholar
Álvaro, J. J., Vennin, E., Villas, E., Destombes, J. & Vizcaïno, D. 2007. Pre-Hirnantian (latest Ordovician) benthic community assemblages: controls and replacements in a siliciclastic-dominated platform of the eastern Anti-Atlas, Morocco. Palaeogeography, Palaeoclimatology, Palaeoecology 245, 20–36.Google Scholar
Barrande, J. 1847. Über die Brachiopoden der silurischen Schichten von Böhmen, I. Naturwissenschaftliche Abhandlungen (Haidingers) 1, 1–154.Google Scholar
Barrande, J. 1848. Über die Brachiopoden der silurischen Schichten von Böhmen, II. Naturwissenschaftliche Abhandlungen (Haidingers) 2, 155–256.Google Scholar
Benharref, M. (Coord.) et al. In press. Carte géologique du Maroc au 1/50 000, feuilles Al Atrous, Irara, Merzouga and Taouz. Notices explicatives. Notes et Mémoires du Service Géologique du Maroc.Google Scholar
Boucot, A. J. 1975. Evolution and Extinction Rate Controls. New York: Elsevier.Google Scholar
Bourahrouh, A., Paris, F. & Elaouad-Debbaj, Z. 2004. Biostratigraphy, biodiversity and palaeoenvironments of the chitinozoans and associated palynomorphs from the Upper Ordovician of the Central Anti-Atlas, Morocco. Review of Palaeobotany and Palynology 130, 17–40.CrossRefGoogle Scholar
Cherns, L., Wheeley, J. R., Popov, L. E., Ghobadi Pour, M., Owens, R. M. & Hemsley, A. R. 2013. Long-period orbital climate forcing in the early Palaeozoic? Journal of the Geological Society, London 10, 707–10.CrossRefGoogle Scholar
Choukri, C., Hamoumi, N. & Attou, A. 2004. Climatic and tectonic control of Ordovician sedimentation in the western and central High Atlas (Morocco). Journal of African Earth Sciences 39, 329–36.Google Scholar
Clerc, S., Boucristiani, J. F., Guiraud, M., Vennin, E., Desaubliaux, G. & Portier, E. 2013. Subglacial to proglacial depositional environments in an Ordovician glacial tunnel valley, Alnif, Morocco. Palaeogeography, Palaeoclimatology, Palaeoecology 370, 127–44.CrossRefGoogle Scholar
Colmenar, J., Harper, D. A. T. & Villas, E. 2014. Morphofunctional analysis of Svobodaina species (Brachiopoda, Heterorthidae) from South-Western Europe. Palaeontology 57, 193–214.Google Scholar
Colmenar, J., Sá, A. A. & Vaz, N. 2014. A draboviid brachiopod association from the Upper Ordovician of Portugal: palaeoecological and palaeogeographical significance. GFF 136, 60–4.CrossRefGoogle Scholar
Colmenar, J., Villas, E. & Vizcaïno, D. 2013. Upper Ordovician brachiopods from the Montagne Noire (France): endemic Gondwanan predecessors of Prehirnantian low-latitude immigrants. Bulletin of Geosciences 88, 153–74.Google Scholar
Destombes, J. 1985 a. Notice explicative de la carte géologique du Maroc au 200.000e “Todhra-Maïder” (Anti-Atlas oriental). Cambrien moyen, Ordovicien, base du Silurien. Rapport inédit du Service de la Carte géologique du Maroc (2nd ed. in 2003), 80 pp.Google Scholar
Destombes, J. 1985 b. Notice explicative de la carte géologique du Maroc au 200.000e “Zagora-Coude du Dra”(Anti-Atlas oriental). Cambrien moyen, Ordovicien, base du Silurien. Rapport inédit du Service de la Carte géologique du Maroc (2nd ed. in 2003), 48 pp.Google Scholar
Destombes, J. 1985 c. Notice explicative de la carte géologique du Maroc au 200.000e “Saghro-Dadès” (Anti-Atlas oriental). Cambrien moyen, Ordovicien, base du Silurien. Rapport inédit du Service de la Carte géologique du Maroc, 36 pp.Google Scholar
Destombes, J. 1987. Notice explicative de la carte géologique du Maroc au 200.000e “Tafilalt-Taouz” (Anti-Atlas oriental). Cambrien moyen, Ordovicien, base du Silurien. Rapport inédit du Service de la Carte géologique du Maroc, 87 pp.Google Scholar
Destombes, J. 2006. Notice explicative de la carte géologique du Maroc au 200.000e “Tafilalt-Taouz” (Anti-Atlas oriental). Cambrien moyen, Ordovicien, base du Silurien. Notes et Mémoires du Service Géologique du Maroc 244bis, 69 pp.Google Scholar
Destombes, J., Hollard, H. & Willefert, S. 1985. Lower Palaeozoic rocks of Morocco. In Lower Palaeozoic Rocks of the World: Lower Palaeozoic Rocks of Northwestern and West-Central Africa, vol. 4 (ed. Holland, C. H.), pp. 91–136. Chichester: John Wiley and Sons.Google Scholar
Elaouad-Debbaj, Z. 1984. Chitinozoaires ashgilliens de l’Anti-Atlas (Maroc). Geobios 17, 45–68.Google Scholar
Elaouad-Debbaj, Z. 1986. Chitinozoaires de la Formation du Ktaoua Inférieur, Ordovicien Supérieur de l’Anti-Atlas (Maroc). Hercynica (sér. 2) 1, 35–55.Google Scholar
Elaouad-Debbaj, Z. 1988. Acritarches de l’Ordovicien supérieur (Caradoc, Ashgill) de l’Anti-Atlas, Maroc. Revue de Micropaleontology 30, 232–48.Google Scholar
El Maazouz, B. & Hamoumi, N. 2007. Différentiation paléogéographique à l’Ordovicien supérieur dans le Tafilalt (Anti-Atlas oriental, Maroc) sous l’interaction de la glaciation et de la tectonique. Comptes Rendus Geoscience 339, 562–71.Google Scholar
Finnegan, S., Bergmann, K., Eiler, J. M., Jones, D. S., Fike, D. A., Eisenman, I., Hughes, N. C., Tripati, A. K. & Fischer, W. W. 2011. The magnitude and duration of Late Ordovician-Early Silurian glaciation. Science 331, 903–6.Google Scholar
Fortey, R. & Cocks, L. R. M. 2005. Late Ordovician global warming – the Boda event. Geology 35, 405–8.CrossRefGoogle Scholar
Gómez, J. J. & Fernández-López, S. 1994. Condensation processes in shallow platforms. Sedimentary Geology 92, 147–59.CrossRefGoogle Scholar
Hall, J. & Whitfield, R. P. 1875. Descriptions of invertebrate fossils mainly from the Silurian system. Geological Survey of Ohio, Report 2 (2), 65–179.Google Scholar
Hallman, D. P., Jonathan, D. M. & Flessa, K. W. 1996. Experimental taphonomy: the effect of shell size and shape on transport within the intertidal zone. In 6th North American Paleontological Convention, Abstracts, p. 157. Paleontological Society Special Publication no. 8.Google Scholar
Hamoumi, N. 1999. Upper Ordovician glaciation spreading and its sedimentary record in Moroccan north Gondwanan margin. Acta Universitatis Carolinae, Geologica 43, 111–4.Google Scholar
Harland, T. L. & Pickerill, R. K. 1987. Epizoic Schizocrania sp. from the Ordovician Trenton Group of Quebec, with comments on mode of life of conulariids. Journal of Paleontology, 61, 844–9.Google Scholar
Harper, D. A. T., Cocks, L. R. M., Popov, L. E., Sheehan, P. M., Bassett, M. G., Copper, P., Holmer, L. E., Jin, J. & Rong, J.-Y. 2004. Brachiopods. In The Great Ordovician Biodiversification Event (eds Webby, B. D., Paris, F., Droser, M. L. & Percival, I. G.), pp. 157–78. New York: Columbia University Press.CrossRefGoogle Scholar
Harper, D. A. T., Rasmussen, C. M. O., Liljeroth, M., Blodgett, R. B., Candela, Y., Jin, J., Percival, I. G., Rong, J.-Y., Villas, E. & Zhan, R. B. 2013. Biodiversity, biogeography and phylogeography of Ordovician rhynchonelliform brachiopods. In Early Palaeozoic Biogeography and Palaeogeography (eds Harper, D. A. T. & Servais, T.), pp. 127–44. Geological Society of London Memoirs no. 38.Google Scholar
Havlíček, V. 1951. The Ordovician Brachiopoda from Bohemia. Rozpravy Ústředního ústavu geologického 12, 1–135.Google Scholar
Havlíček, V. 1970. Heterorthidae (Brachiopoda) in the Mediterranean Province. Sborník Geologických Věd, Paleontologie 12, 7–39.Google Scholar
Havlíček, V. 1971. Brachiopodes de l’Ordovicien du Maroc. Notes et Mémoires du Service géologique du Maroc 230, 1–135.Google Scholar
Havlíček, V. 1977. Brachiopods of the order Orthida in Czechoslovakia. Rozpravy Ústředního ústavu geologického 44, 1–327.Google Scholar
Havlíček, V. 1981. Upper Ordovician brachiopods from the Montagne Noire. Paleontographica, Abteilung A 176, 1–34.Google Scholar
Havlíček, V. 1982. Ordovician of Bohemia: development of the Prague Basin and its benthic communities. Sborník Geologických Věd, Geologie 37, 103–36.Google Scholar
Keller, M. & Lehnert, O. 2010. Ordovician paleokarst and quartz sand: evidence of volcanically triggered extreme climates? Palaeogeography, Palaeoclimatology, Palaeoecology, 296, 297–309.Google Scholar
Lockley, M. G. & Antia, D. D. J. 1980. Anomalous occurrences of the lower Palaeozoic brachiopod Schizocrania . Palaeontology 23, 707–13.Google Scholar
Loi, A., Ghienne, J. F., Dabard, M. P., Paris, F., Botquelen, A., Christ, N., Elaouad-Debbaj, Z., Gorini, A., Vidal, M., Videt, B. & Destombes, J. 2010. The Late Ordovician glacio-eustatic record from a high-latitude storm-dominated shelf succession: the Bou Ingarf section (Anti-Atlas, Southern Morocco). Palaeogeography, Palaeoclimatology, Palaeoecology 296, 332–58.Google Scholar
McCoy, F. 1851. Description of the British Palaeozoic fossils in the Geological Museum of the University of Cambridge. University Press, 184 pp.Google Scholar
NACSN (North American Commission on Stratigraphic Nomenclature). 1983. North American Stratigraphic Code. American Association of Petroleum Geologists Bulletin 67, 841–75.Google Scholar
Page, A., Zalasiewicz, J., Williams, M. & Popov, L. 2007. Were transgressive black shales a negative feedback modulating glacioeustasy in the Early Palaeozoic Icehouse? In Deep-Time Perspectives on Climate Change: Marrying the Signal from Computer Models and Biological Proxies (eds Williams, M., Haywood, A. M., Gregory, F. J. & Schmidt, D. N.), pp. 123–56. Micropalaeontological Society, Special Publications no. 2.CrossRefGoogle Scholar
Paris, F. 1990. The Ordovician chitinozoan biozones of the Northern Gondwana Domain. Review of Palaeobotany and Palynology 66, 181–209.Google Scholar
Paris, F. 1999. Palaeobiodiversification of Ordovician chitinozoans from northern Gondwana. Acta Universitatis Carolinae, Geologica 43, 283–6.Google Scholar
Paris, F., Elaouad-Debbaj, Z., Jaglin, J. C., Massa, D. & Oulebsir, L. 1995. Chitinozoans and Late Ordovician glacial events on Gondwana. In Ordovician Odyssey: Short Papers for the 7th International Symposium on the Ordovician System Las Vegas Nevada (eds Cooper, J. D., Droser, M. L. & Finney, S. C.), pp. 171–7. Fullerton, California: Pacific Section Society for Sedimentary Geology (SEPM).Google Scholar
Paris, F., Verniers, J., Achab, A., Albani, R., Ancilletta, A., Asselin, E., Chen, X. H., Fatka, O., Grahn, Y., Molyneux, S., Nolvak, J., Samuelsson, J., Sennikov, N. V., Soufiane, A., Wang, X. F. & Winchester-Seeto, T. 1999. Correlation of Ordovician regional chitinozoan biozonations. Acta Universitatis Carolinae, Geologica 43, 291–4.Google Scholar
Pickerill, R. K. & Brenchley, P. J. 1979. Caradoc marine communities of the south Berwyn Hills, North Wales. Palaeontology 22, 229–64.Google Scholar
Rong, J.-Y. 1984. Distribution of the Hirnantia fauna and its meaning. In Aspects of the Ordovician System (ed. Bruton, D. L.), pp. 101–12. Paleontological Contributions from the University of Oslo no. 295. Oslo: Universitetsforlaget.Google Scholar
Rong, J.-Y. 1986. Ecostratigraphy and community analysis of Late Ordovician and Silurian in southern China. In Selected Papers of the 13th and 14th Annual Convention of the Palaeontological Society of China (ed. Palaeontological Society of China), pp. 1–24. Hefei: Anhui Science and Technology Publishing House (in Chinese with English summary).Google Scholar
Rowell, A. J. 1965. Inarticulata. In Treatise on Invertebrate Paleontology, part H, Brachiopoda, vol. 1. (ed. Moore, R. C.), pp. H260–9. Boulder, Colorado: Geological Society of America and Lawrence, Kansas: University of Kansas Press.Google Scholar
Simões, M. G. & Kowalewski, M. 2003. Modern accumulations of brachiopod shells in unconsolidated surficial beach deposits, northern coast of São Paulo State, Brazil: taphonomic implications for the genesis of skeletal concentration. In 3rd Latin American Congress of Sedimentology, Belém, Brazil, Abstracts, pp. 220–3.Google Scholar
Simões, M. G., Rodrigues, S. C., Leme, J. M., Bissaro, M. & Junior, C. 2005. The settling behaviour of brachiopod shells: stratigraphical and taphonomical implications to shell bed formation and paleoecology. Revista Brasileira de Geociencias 35, 383–91.Google Scholar
Sowerby, J. de C. 1839. Fossil shells of the lower Ludlow age. In The Silurian System, Founded on Geological Researches in the Counties of Salop, Hereford, Radnor, Montgomery, Caermarthen, Brecon, Pembroke, Monmouth, Gloucester, Worcester, and Stafford; With Descriptions of the Coalfields and Overlying Formations (ed. Murchinson, R. I.). London: John Murray.Google Scholar
Temple, J. T. 1965. Upper Ordovician brachiopods from Poland and Britain. Acta Palaeontologica Polonica 10 (3), 379–468.Google Scholar
Videt, B., Paris, F., Rubino, J. L., Boumendjel, K., Dabard, M. P., Loi, A., Ghienne, J. F., Marante, A. & Gorino, A. 2010. Biostratigraphical calibration of third order Ordovician sequences on the northern Gondwana platform. Palaeogeography, Palaeoclimatology, Palaeoecology 296, 359–75.Google Scholar
Villas, E., Vennin, E., Álvaro, J. J., Hamman, W., Herrera, Z. A. & Piovano, E. L. 2002. The late Ordovician carbonate sedimentation as a major triggering factor of the Hirnantian glaciation. Bulletin de la Societé géologique de France 173, 569–78.Google Scholar
Villas, E., Vizcaïno, D., Álvaro, J. J., Destombes, J. & Vennin, E. 2006. Biostratigraphic control based on brachiopods of the latest Ordovician glaciogenic unconformity in Alnif, eastern Anti-Atlas, Morocco. Geobios 39, 727–37.CrossRefGoogle Scholar
Wang, Y., Boucot, A. J., Rong, J.-Y. & Yang, X. C. 1987. Community paleoecology as a geologic tool: the Chinese Ashgillian–Eifelian (latest Ordovician through Devonian) as an example. Geological Society of America, Special Papers 211, 1–100.Google Scholar
Webby, B. D. 2002. Patterns of Ordovician reef development. In Phanerozoic Reef Patterns (eds Kiessling, W., Flügel, E. & Golonka, J.), pp. 129–79. Society for Sedimentary Geology (SEPM), Special Publications no. 72.Google Scholar
Webby, B. D. 2004. Introduction. In The Great Ordovician Biodiversification Event (eds Webby, B. D., Paris, F., Droser, M. L. & Percival, I. G.), pp. 1–37. New York: Columbia University Press.CrossRefGoogle Scholar
Whittaker, A., Cope, J. C. W., Cowie, J. W., Gibbons, W., Haikwood, E. A., House, M. R., Jenkins, D. G., Rawson, P. F., Rushton, A. W. A., Smith, D. G., Thomas, A. T. & Wimbledon, W. A. 1991. A guide to stratigraphical nomenclature. Stratigraphic Committee of the Geological Society of London. Journal of the Geological Society, London 148, 813–24.Google Scholar
Wood, A. R., Kraus, M. J. & Gingerich, P. D. 2008. Downslope fossil contamination: mammal-bearing fluvial conglomerates and the Paleocene–Eocene faunal transition (Willwood Formation, Bighorn Basin, Wyoming). Palaios 23, 380–90.Google Scholar