Geochemistry of the early Cambrian succession in the western Anti-Atlas, Morocco: implications on provenance and paleoredox conditions
| Autor: | Abdelfattah Azizi, Abderrazak El Albani, Khadija El Hariri, Asmaa El Bakhouch, Olev Vinn, Ahmid Hafid, Kalle Kirsimäe |
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| Jazyk: | angličtina |
| Rok vydání: | 2023 |
| Předmět: | |
| Zdroj: | Estonian Journal of Earth Sciences, Vol 72, Iss 2, Pp 171-184 (2023) |
| Druh dokumentu: | article |
| ISSN: | 1736-4728 1736-7557 |
| DOI: | 10.3176/earth.2023.83 |
| Popis: | The Igoudine and Amouslek formations (TerreneuvianâCambrian Epoch 2 boundary) in the western Anti-Atlas of Morocco record the replacement of stromatolite-dominated microbial consortia by thrombolite-metazoan consortia. Carbonate and calcareous shales of both formations have been analyzed for major, trace, and rare earth elements to study their geochemical characteristics and evaluate the provenance of the terrigenous fraction and paleoredox conditions. Discrimination diagrams for the source rocks based on major elements and selected trace elements indicate that the terrigenous fractions of the sediments were likely derived from predominantly felsic rocks, and the source rocks have been identified to be the PaleoproterozoicâNeoproterozoic granites and metasediments of the Kerdous inlier. Paleoredox proxies such as U/Al, V/Al and Mo/Al suggest that the Igoudine and Amouslek formations were deposited in the oxic environment. Our data show that the local water column was prevailingly oxidized before, during and after the transition from the microbial consortium (stromatolite-dominated biota) to the thrombolite-archaeocyathan consortium and shelly metazoans within the studied interval. This implies that the seawater redox status was not driving this change in these biological communities. |
| Databáze: | Directory of Open Access Journals |
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