Hostname: page-component-848d4c4894-wg55d Total loading time: 0 Render date: 2024-05-16T19:30:58.580Z Has data issue: false hasContentIssue false
  • English
  • Français

Early biomineralization and exceptional preservation of the first thrombolite reefs with archaeocyaths in the lower Cambrian of the western Anti-Atlas, Morocco

Published online by Cambridge University Press:  18 October 2022

Abdelfattah Azizi Open the ORCID record for Abdelfattah Azizi [Opens in a new window] ,
Abderrazak El Albani ,
Asmaa El Bakhouche ,
Olev Vinn Open the ORCID record for Olev Vinn [Opens in a new window] ,
Olabode M. Bankole ,
Claude Fontaine ,
Ahmid Hafid ,
Khaoula Kouraiss  and
Khadija El Hariri
Abdelfattah Azizi*
Affiliation:
Département de Géologie, Faculté des Sciences et Techniques, Université Cadi-Ayyad, BP 549, 40000 Marrakesh, Morocco
Abderrazak El Albani
Affiliation:
Laboratoire IC2MP 7285 CNRS-INSU, Université de Poitiers, 86022 Poitiers, France
Asmaa El Bakhouche
Affiliation:
Département de Géologie, Faculté des Sciences et Techniques, Université Cadi-Ayyad, BP 549, 40000 Marrakesh, Morocco
Olev Vinn
Affiliation:
Department of Geology, University of Tartu, Ravila 14A, 50411 Tartu, Estonia
Olabode M. Bankole
Affiliation:
Laboratoire IC2MP 7285 CNRS-INSU, Université de Poitiers, 86022 Poitiers, France
Claude Fontaine
Affiliation:
Laboratoire IC2MP 7285 CNRS-INSU, Université de Poitiers, 86022 Poitiers, France
Ahmid Hafid
Affiliation:
Département de Géologie, Faculté des Sciences et Techniques, Université Cadi-Ayyad, BP 549, 40000 Marrakesh, Morocco
Khaoula Kouraiss
Affiliation:
Département de Géologie, Faculté des Sciences et Techniques, Université Cadi-Ayyad, BP 549, 40000 Marrakesh, Morocco
Khadija El Hariri
Affiliation:
Département de Géologie, Faculté des Sciences et Techniques, Université Cadi-Ayyad, BP 549, 40000 Marrakesh, Morocco
*
Author for correspondence: A. Azizi, Email: a.azizi@uca.ma
Get access Rights & Permissions [Opens in a new window]

Abstract

Thrombolite reefs with archaeocyaths are common in the subtidal limestones of the lower Cambrian in the western Anti-Atlas of Morocco. The Igoudine Formation of the Tata Group recorded the first replacement of the microbial consortium (stromatolite-dominated) by thrombolite reefs with archaeocyaths and shelly metazoans. In order to better understand the role of the microbial community in the formation of thrombolite reefs with archaeocyaths across this critical transition, the macro-, micro- and ultra-fabric of thrombolites have been studied in detail. Three major components are identified within the first thrombolytic reef: archaeocyaths, calcimicrobes and micritic matrix. The studied thrombolites are typically dominated by the calcimicrobe Renalcis with subordinate Epiphyton and Girvanella. Scanning electron microscopy of the dark micrite of the Renalcis chambers showed amorphous translucent sheet-like structures interpreted as extracellular polymeric substances, closely associated with organominerals including nanoglobules and polyhedrons. Exceptionally well-preserved Renalcis chambers contain bacterial fossils similar to those described in modern microbialites, including microspherical coccoid fossils and filamentous bacteria that are either spaced or in close associations forming colonies. These organomineralization-related features suggest a bacterial origin for the Renalcis calcimicrobe. The matrices between the Renalcis chambers consist predominantly of clotted peloidal micrite. Mineralization of Renalcis microframes may involve two major biomineralization processes: (1) replacement of organic matter by organominerals resulting from anaerobic degradation of extracellular polymeric substances and bacterial sheaths and (2) encrustation of bacterial sheaths and extracellular polymeric substances due to increasing alkalinity of the microenvironment. These mechanisms played a crucial role in the early diagenetic cementation and preservation of the studied reefs.

Keywords

bacterial fossilsnanoglobulespyrite framboidsRenalcis
Type
Original Article
Information
Geological Magazine , Volume 160 , Issue 3 , March 2023 , pp. 428 - 443
Copyright
© The Author(s), 2022. Published by Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Adachi, N, Nakai, T, Ezaki, Y and Liu, J (2014) Late Early Cambrian archaeocyath reefs in Hubei Province, South China: modes of construction during their period of demise. Facies 60, 703–17.CrossRefGoogle Scholar
Aiken, JD (1967) Classification and environmental significance of cryptalgal limestones and dolomites, with illustrations from the Cambrian and Ordovician of southwestern Alberta. Journal of Sedimentary Research 37, 1163–78.Google Scholar
Aloisi, G, Gloter, A, Kruger, M, Wallmann, K, Guyot, F and Zuddas, P (2006) Nucleation of calcium carbonate on bacterial nanoglobules. Geology 34, 1017–20.CrossRefGoogle Scholar
AlShuaibi, AA, Khalaf, FI and Al-Zamel, A (2015) Calcareous thrombolitic crust on Late Quaternary beachrocks in Kuwait, Arabian Gulf. Arabian Journal of Geosciences 8, 9721–32.CrossRefGoogle Scholar
Álvaro, JJ, Benziane, F, Thomas, R, Walsh, GJ and Yazidi, A (2014) Neoproterozoic–Cambrian stratigraphic framework of the Anti-Atlas and Ouzellagh promontory (High Atlas), Morocco. Journal of African Earth Sciences 98, 19–33.CrossRefGoogle Scholar
Álvaro, JJ and Clausen, S (2006) Microbial crusts as indicators of stratigraphic diastems in the Cambrian Micmacca Breccia, Moroccan Atlas. Sedimentary Geology 185, 255–65.CrossRefGoogle Scholar
Álvaro, JJ and Debrenne, F (2010) The Great Atlasian Reef Complex: an early Cambrian subtropical fringing belt that bordered West Gondwana. Palaeogeography, Palaeoclimatology, Palaeoecology 294, 120–32.CrossRefGoogle Scholar
Álvaro, JJ, Ezzouhairi, H, Vennin, E, Ribeiro, ML, Clausen, S, Charif, A, Ait Ayad, N and Moreira, ME (2006) The Early-Cambrian Boho volcano of the El Graara massif, Morocco: petrology, geodynamic setting and coeval sedimentation. Journal of African Earth Sciences 44, 396–410.CrossRefGoogle Scholar
Arp, G, Reimer, A and Reitner, J (2001) Photosynthesis-induced biofilm calcification and calcium concentrations in Phanerozoic oceans. Science 292, 1701–4.CrossRefGoogle ScholarPubMed
Arp, G, Reimer, A and Reitner, J (2003) Microbialite formation in seawater of increased alkalinity, Satonda Crater Lake, Indonesia. Journal of Sedimentary Research 73, 105–27.CrossRefGoogle Scholar
Barrett, J, Spentzos, A and Works, C (2009) Isolation and characterization of extracellular polymeric substances from micro-algae Dunaliella salina under salt stress. Bioresource Technology 100, 3382–6.Google Scholar
Bartley, JK (1996) Actualistic taphonomy of cyanobacteria: implications for the Precambrian fossil record. Palaios 11, 571–86.CrossRefGoogle Scholar
Benssaou, M and Hamoumi, N (2004) Les microbialites de l’Anti-Atlas occidental (Maroc): marqueurs stratigraphiques et témoins des changements environnementaux au Cambrien inférieur. Comptes Rendus Geosciences 336, 109–16.CrossRefGoogle Scholar
Braissant, O, Decho, AW, Dupraz, C, Glunk, C, Przekop, KM and Visscher, PT (2007) Exopolymeric substances of sulfate-reducing bacteria: interactions with calcium at alkaline pH and implication for formation of carbonate minerals. Geobiology 5, 401–11.CrossRefGoogle Scholar
Burne, RV and Moore, LS (1987) Microbialites: organosedimentary deposits of benthic microbial communities. Palaios 2, 241–54.CrossRefGoogle Scholar
Campbell, KA, Francis, DA, Collins, M, Gregory, MR, Campbell, SN, Greinert, J and Aharon, P (2008) Hydrocarbon seep-carbonates of a Miocene forearc (East Coast Basin), North Island, New Zealand. Sedimentary Geology 204, 83–105.CrossRefGoogle Scholar
Cayeux, M (1935) Les Roches Sédimentaire de France: Roche Carbonatées. Paris: Masson, 463 pp.Google Scholar
Chafetz, HS (1986) Marine peloids; a product of bacterially induced precipitation of calcite Journal of Sedimentary Petrology 56, 812–17.Google Scholar
Christensen, B E and Characklis, W G (1990) Biofilms. New York: Wiley Interscience.Google Scholar
Clausen, S, Álvaro, JJ and Zamora, S (2014) Replacement of benthic communities in two Neoproterozoic–Cambrian subtropical-to-temperate rift basins, High Atlas and Anti-Atlas, Morocco. Journal of African Earth Sciences 98, 72–93.CrossRefGoogle Scholar
Crawford, D (2007) Deadly Companions: How Microbes Shaped Our History. Oxford: Oxford University Press.Google Scholar
Debrenne, F (2007) Lower Cambrian archaeocyathan bioconstructions. Comptes Rendus Palevol 6, 5–19.CrossRefGoogle Scholar
Debrenne, F and Debrenne, M (1995) Archaeocyaths of the lower Cambrian of Morocco. Beringeria Special Issue 2, 121–45.Google Scholar
Debrenne, F, Gandin, A and Courjault-Radé, P (2002) Facies and depositional setting of the Lower Cambrian archeocyath–bearing limestones of southern Montagne Noire (Massif Central, France). Bulletin de la Société géologique de France 173, 533–46.CrossRefGoogle Scholar
Debrenne, F, Gandin, A and Rowland, SM (1989) Lower Cambrian bioconstructions in northwestern Mexico (Sonora). Depositional setting, paleoecology and systematics of archaeocyaths. Geobios 22, 137–95.CrossRefGoogle Scholar
Decho, AW, Visscher, PT and Reid, RP (2005) Production and cycling of natural microbial exopolymers (EPS) within a marine stromatolite. Palaeogeography, Palaeoclimatology, Palaeoecology 219, 71–86.CrossRefGoogle Scholar
Défarge, C, Trichet, J and Coute, A (1994) On the appearance of cyanobacterial calcification in modern stromatolites. Sedimentary Geology 94, 11–19.CrossRefGoogle Scholar
Défarge, C, Trichet, J, Jaunet, AM, Robert, M, Tribble, J and Sansone, FJ (1996) Texture of microbial sediments revealed by cryo-scanning electron microscopy. Journal of Sedimentary Research 66, 935–47.Google Scholar
Destombes, J, Hollard, H and Willefert, S (1985) Lower Palaeozoic rocks of Morocco. In Lower Palaeozoic Rocks of the World: Lower Palaeozoic of North-Western and West Central Africa: Vol. 4 (ed. Holland, CH), pp. 157–84. Chichester: John Wiley and Sons.Google Scholar
Dupraz, C, Reid, RP, Braissant, O, Decho, AW, Norman, RS and Visscher, PT (2009) Processes of carbonate precipitation in modern microbial mats. Earth-Science Reviews 96, 141–62.CrossRefGoogle Scholar
Dupraz, C, Visscher, PT, Baumgartner, LK and Reid, RP (2004) Microbe–mineral interactions: early carbonate precipitation in a hypersaline lake (Eleuthera Island, Bahamas). Sedimentology 51, 745–65.CrossRefGoogle Scholar
Fluegel, E (2010) Microfacies of Carbonate Rocks. Berlin: Springer, 997 pp.CrossRefGoogle Scholar
Gandin, A and Debrenne, F (2010) Distribution of the archaeocyath–calcimicrobial bioconstructions on the Early Cambrian shelves. Palaeoworld 19, 222–41.CrossRefGoogle Scholar
Gandin, A, Debrenne, F and Debrenne, M (2007) Anatomy of the Early Cambrian ‘La Sentinella’ reef complex, Serra Scoris, SW Sardinia, Italy. In Palaeozoic Reefs and Bioaccumulations: Climatic and Evolutionary Controls (eds Álvaro, JJ, Aretz, M, Boulvain, F, Munnecke, A, Vachard, D and Vennin, E), pp. 29–50. Geological Society of London, Special Publication no. 275.Google Scholar
Gandin, A and Luchinina, V (1993) Occurrence and environmental meaning of the Early Cambrian calcareous algae of the Tianheban Formation of China (Yangtze Area). In Studies on Fossil Benthic Algae (eds Barattolo, F, De Castro, P and Parente, M), pp. 211–17. Societá Paleontologica Italiana, Bollettino vol. 1.Google Scholar
Gasquet, D, Ennih, N, Liégéois, JP, Soulaimani, A and Michard, A (2008) The Pan-African Belt. In Continental Evolution: The Geology of Morocco (eds Michard, A, Saddiqi, O, Chalouan, A and Frizon de Lamotte, D), pp. 33–64. Berlin: Springer.CrossRefGoogle Scholar
Geyer, G and Landing, E (1995) Morocco’95. The Lower–Middle Cambrian standard of Gondwana. Beringeria Special Issue 2, 1–171.Google Scholar
Gischler, E, Gibson, MA and Oschmann, W (2008) Giant Holocene freshwater microbialites, Laguna Bacalar, Quintana Roo, Mexico. Sedimentology 55, 1293–309.CrossRefGoogle Scholar
Heindel, K, Birgel, D, Brunner, B, Thiel, V, Westphal, H, Gischler, E, Ziegenbalg, SB, Cabioch, G, Sjövall, P and Peckmann, J (2012) Post-glacial microbialite formation in coral reefs of the Pacific, Atlantic, and Indian Oceans. Chemical Geology 304, 117–30.CrossRefGoogle Scholar
Hofmann, HJ (1973) Stromatolite characteristics and utility. Earth-Science Review 9, 339–73.CrossRefGoogle Scholar
Hupé, P (1960) Sur le Cambrien inférieur du Maroc. In Report of the 21st International Geological Congress, Norden, Part 8, pp. 75–85.Google Scholar
Jahnert, RJ and Collins, LB (2012) Characteristics, distribution and morphogenesis of subtidal microbial systems in Shark Bay, Australia. Marine Geology 303–306, 115–36.CrossRefGoogle Scholar
James, NP and Gravestock, DI (1990) Lower Cambrian shelf and shelf margin buildups, Flinders Ranges, South Australia. Sedimentology 37, 455–80.CrossRefGoogle Scholar
Jones, B (2011) Biogenicity of terrestrial oncoids formed in soil pockets, Cayman Brac, British West Indies. Sedimentary Geology 236, 95–108.CrossRefGoogle Scholar
Kershaw, S, Li, Y, Crasquin-Soleau, S, Feng, Q, Mu, X, Collin, P-Y, Reynolds, A and Guo, L (2007) Earliest Triassic microbialites in the South China block and other areas: controls on their growth and distribution. Facies 53, 409–25.CrossRefGoogle Scholar
Kershaw, S, Zhang, T and Li, Y (2021) Calcilobes wangshenghaii n. gen., n. sp., microbial constructor of Permian–Triassic boundary microbialites of South China, and its place in microbialite classification. Facies 67, 28. doi: 10.1007/s10347-021-00636-x.CrossRefGoogle Scholar
Kruse, PD, Zhuravlev, AY and James, NP (1995) Primordial metazoan–calcimicrobial reefs: Tommotian (Early Cambrian) of the Siberian Platform. Palaios 10, 291–321.CrossRefGoogle Scholar
Laval, B, Cady, SL, Pollack, JC, McKay, CP, Bird, JS, Grotzinger, JP, Ford, DC and Bohm, HR (2000) Modern freshwater microbialite analogues for ancient dendritic reef structures. Nature 407, 626–9.CrossRefGoogle ScholarPubMed
Luchinina, VA (2009) Remalcis and Epiphyton as different stages in the life cycle of calcareous algae. Paleontological Journal 43, 463–8.CrossRefGoogle Scholar
Mackey, TJ, Sumner, DY, Hawes, I, Jungblut, AD, Lawrence, J, Leidman, S and Allen, B (2017) Increased mud deposition reduces stromatolite complexity. Geology 45, 663–6.CrossRefGoogle Scholar
Maclean, L, Tyliszczak, T, Gilbert, P, Zhou, D, Pray, TJ, Onstott, TC and Southam, G (2008) A high-resolution chemical and structural study of framboidal pyrite formed within a low-temperature bacterial biofilm. Geobiology 6, 471–80.CrossRefGoogle ScholarPubMed
Maloof, AC, Schrag, DP, Crowley, JL and Bowring, SA (2005) An expanded record of Early Cambrian carbon cycling for the Anti-Atlas margin, Morocco. Canadian Journal of Earth Sciences 42, 2195–216.CrossRefGoogle Scholar
Mamet, B (1991) Carboniferous calcareous algae. In Calcareous Algae and Stromatolites (ed. Riding, R), pp. 370–451. Berlin: Springer.CrossRefGoogle Scholar
Mishra, A, Fischer, MK and Bäuerle, P (2009) Metal-free organic dyes for dye-sensitized solar cells: from structure: property relationships to design rules. Angewandte Chemie International Edition 48, 2474–99.CrossRefGoogle ScholarPubMed
Mobberley, JM, Ortega, MC and Foster, JS (2012) Comparative microbial diversity analyses of modern marine thrombolitic mats by barcoded pyrosequencing. Environmental Microbiology 14, 82–100.CrossRefGoogle ScholarPubMed
Monninger, W (1979) The Section of Tiout (Precambrian/Cambrian Boundary Beds, Anti-Atlas, Morocco): An Environmental Model. Würzburg: Arbeiten aus dem Paläontologischen Institut Würzburg vol. 1, 289 pp.Google Scholar
Myshrall, KL, Mobberley, JM, Green, SJ, Visscher, PT, Havemann, SA, Reid, RP and Foster, JS (2010) Biogeochemical cycling and microbial diversity in the thrombolitic microbialites of Highborne Cay, Bahamas. Geobiology 8, 337–54.CrossRefGoogle ScholarPubMed
Obst, M, Wehrli, B and Dittrich, M (2009) CaCO3 nucleation by cyanobacteria: laboratory evidence for a passive, surface induced mechanism. Geobiology 7, 324–47.CrossRefGoogle ScholarPubMed
Ohfuji, H and Rickard, D (2005) Experimental syntheses of framboids – a review. Earth-Science Reviews 71, 147–70.CrossRefGoogle Scholar
Pan, J, Zhao, H, Tucker, ME, Zhou, J, Jiang, M, Wang, Y, Zhao, Y, Sun, B, Han, Z and Yan, H (2019) Biomineralization of monohydrocalcite induced by the halophile Halomonas smyrnensis WMS-3. Minerals 9, 632. doi: 10.3390/min9100632.CrossRefGoogle Scholar
Perri, E and Spadafora, A (2011) Evidence of microbial biomineralization in modern and ancient stromatolites. In Stromatolites: Interaction of Microbes with Sediments (eds Tewari, V and Seckbach, J), pp. 631–49. Dordrecht: Springer-Verlag.CrossRefGoogle Scholar
Perri, E and Tucker, ME (2007) Bacterial fossils and microbial dolomite in Triassic stromatolites. Geology 35, 207–10.CrossRefGoogle Scholar
Perri, E, Tucker, ME and Spadafora, A (2012) Carbonate organo-mineral micro- and ultrastructures in sub-fossil stromatolites: Marion Lake, South Australia. Geobiology 10, 105–17.CrossRefGoogle ScholarPubMed
Planavsky, N and Ginsburg, RN (2009) Taphonomy of modern marine Bahamian microbialites. Palaios 24, 5–24.CrossRefGoogle Scholar
Pratt, BR (1984) Epiphyton and Renalcis; diagenetic microfossils from calcification of coccoid blue-green algae. Journal of Sedimentary Petrology 54, 948–70.Google Scholar
Puckett, MK, McNeal, KS, Kirkland, BL, Corley, ME and Ezell, JE (2011) Biogeochemical stratification of carbonate dissolution precipitation in hypersaline microbial mats (Salt Pond, San Salvador, Tha Bahamas). Aquatic Geochemistry 17, 397–418.CrossRefGoogle Scholar
Rees, MR, Pratt, BR and Rowell, AJ (1989) Early Cambrian reefs, reef complexes, and associated lithofacies of the Shackleton Limestone, Transantarctic Mountains. Sedimentology 36, 341–61.CrossRefGoogle Scholar
Reid, RP (1987) Nonskeletal peloidal precipitates in Upper Triassic reefs, Yukon Territory (Canada). Journal of Sedimentary Petrology 57, 893–900.Google Scholar
Riding, R (2000) Microbial carbonate: the geological record of calcified bacterial-algal mats and biofilm. Sedimentology 47, 179–214.CrossRefGoogle Scholar
Riding, R (2002) Structure and composition of organic reefs and carbonate mud mounds: concepts and categories. Earth-Science Reviews 58, 163–231.CrossRefGoogle Scholar
Riding, R (2008) Abiogenic, microbial and hybrid authigenic carbonate crusts: components of Precambrian stromatolites. Geologia Croatica 61, 73–103.CrossRefGoogle Scholar
Riding, R (2011) The nature of stromatolites: 3,500 million years of history and a century of research. In Advances in Stromatolite Geobiology (eds Reitner, J, Quéric, N-V and Arp, G), pp. 29–74. Berlin: Springer-Verlag.CrossRefGoogle Scholar
Riding, R and Zhuravlev, AY (1995) Structure and diversity of oldest sponge–microbe reefs: Lower Cambrian, Aldan River, Siberia. Geology 23, 649–52.2.3.CO;2>CrossRefGoogle Scholar
Saadi, S, Hilali, E, Bensaïd, M, Boudda, A and Dahmani, M (1983) Carte Géologique de Maroc, Scale 1:1,000,000. Rabat: Ministère du l’Énergie et des Mines, Service Géologique du Maroc.Google Scholar
Sánchez-Román, M, Vasconcelos, C, Schmid, T, Dittrich, M, McKenzie, JA, Zenobi, R and Rivadeneyra, MA (2008) Aerobic microbial dolomite at the nanometer scale: implications for the geologic record. Geology 36, 879–82.CrossRefGoogle Scholar
Sass, H, Cypionka, H and Babenzien, H (2006) Vertical distribution of sulfate-reducing bacteria at the oxic-anoxic interface in sediments of oligotrophic Lake Stechlin. FEMS Microbiology Ecology 22, 245–55.CrossRefGoogle Scholar
Sass, AM, Eschemann, A, Kuhl, M, Thar, R, Sass, H and Cypionka, H (2002) Growth and chemosensory behavior of sulfate-reducing bacteria in oxygen–sulfide gradients. FEMS Microbiology Ecology 40, 47–54.Google ScholarPubMed
Schmitt, M (1979) The Section of Tiout (Precambrian/Cambrian Boundary Beds, Anti-Atlas, Morocco): Stromatolites and their Biostratigraphy. Würzburg: Arbeiten aus dem Paläontologischen Institut Würzburg vol. 2, 188 pp.Google Scholar
Schmitt, M and Monninger, W (1977) Stromatolites and thrombolites in Precambrian/Cambrian boundary beds of the Anti-Atlas, Morocco: preliminary results. In Fossil Algae (ed. Flügel, E), pp. 80–5. Berlin: Springer.CrossRefGoogle Scholar
Shen, B, Qin, J, Tenger, B, Pan, A, Yang, Y and Bian, L (2017) Identification of bacterial fossils in marine source rocks in South China. Acta Geochimica 37, 68–79.CrossRefGoogle Scholar
Spadafora, A, Perri, E, Mckenzie, J and Vasconcelos, C (2010) Microbial biomineralization processes forming modern Ca:Mg carbonate stromatolites. Sedimentology 57, 27–40.CrossRefGoogle Scholar
Stephens, NP and Sumner, DY (2002) Renalcids as fossilized biofilm clusters. Palaios 17, 225–36.2.0.CO;2>CrossRefGoogle Scholar
Sun, SQ and Wright, VP (1989) Peloidal fabrics in Upper Jurassic reefal limestones, Weald Basin, southern England. Sedimentary Geology 65, 165–81.CrossRefGoogle Scholar
Tang, HS, Chen, YJ, Santosh, M, Zhong, H and Yang, T (2013) REE geochemistry of carbonates from the Guanmenshan Formation, Liaohe Group, NE Sino-Korean Craton: implications for seawater compositional change during the Great Oxidation Event. Precambrian Research 227, 316–36.CrossRefGoogle Scholar
Tang, DJ, Shi, XY, Jiang, GQ, Pei, Y and Zhang, W (2012) Mesoproterozoic biogenic thrombolites from the North China platform. International Journal of Earth Sciences 102, 401–13.CrossRefGoogle Scholar
Thomas, RJ, Fekkak, A, Ennih, N, Errami, E, Loughlin, SC, Gresse, PG, Chevallier, LP and Liégeois, JP (2004) A new lithostratigraphic framework for the Anti-Atlas Orogen, Morocco. Journal of African Earth Sciences 39, 217–26.CrossRefGoogle Scholar
Turner, EC, James, NP and Narbonne, GM (2000) Taphonomic control on microstructure in Early Neoproterozoic reefal stromatolites and thrombolites. Palaios 15, 87–111.2.0.CO;2>CrossRefGoogle Scholar
Walsh, GJ, Benziane, F, Aleinikoff, JN, Harrison, RW, Yazidi, A, Burton, WC, Quick, JE and Saadane, A (2012) Neoproterozoic tectonic evolution of the Jebel Saghro and Bou Azzer-El Graara inliers, eastern and central Anti-Atlas Morocco. Precambrian Research 216, 23–62.CrossRefGoogle Scholar
Walter, MR and Heys, GR (1985) Links between the rise of the metazoan and the decline of stromatolites. Precambrian Research 29, 149–74.CrossRefGoogle Scholar
Wilkin, R and Barnes, HL (1997) Formation processes of framboidal pyrite. Geochimica et Cosmochimica Acta 61, 323–39.CrossRefGoogle Scholar
Woo, J, Chough, SK and Han, Z (2008) Chambers of Epiphyton thalli in microbial buildups, Zhangxia Formation (Middle Cambrian), Shandong Province, China. Palaios 23, 55–64.CrossRefGoogle Scholar
Zatoń, M, Kremer, B and Marynowskii, L (2012) Middle Jurassic (Bathonian) encrusted oncoids from the Polish Jura, southern Poland. Facies 58, 57–77.CrossRefGoogle Scholar
Zhang, WH, Shi, X, Jiang, G, Tang, D and Wang, X (2015) Mass-occurrence of oncoids at the Cambrian Series 2–Series 3 transition: implications for microbial resurgence following an early Cambrian extinction. Gondwana Research 28, 432–50.CrossRefGoogle Scholar
Zhao, Y, Yan, H, Tucker, ME, Han, M, Zhao, H, Mao, G, Peng, C and Han, Z (2020) Calcimicrobes in Cambrian microbialites (Shandong, North China) and comparison with experimentally produced biomineralization precipitates. Carbonates and Evaporites 35, 1–15.CrossRefGoogle Scholar