- Source: El Mers Group
The El Mers Group is a geological group in the Middle Atlas of Morocco. It is subdivided into three formations named the El Mers I, II, and III Formations, respectively. It is a marine deposit primarily consisting of marl, with gypsum present in the upper part of unit 3. It is the lateral equivalent of the terrestrial Guettioua Sandstone. Dinosaur remains are among the fossils that have been recovered from the group, most notably those of sauropods and the unusual thyreophorans Adratiklit, Thyreosaurus, and Spicomellus.
Description and paleoenvironment
The El Mers formations are composed primarily of marls with intermittent layers of limestone and sandstone, characterized by abundant organic matter and benthic fauna. It is delineated into five distinct members, each exhibiting diverse lithological characteristics. The three members comprise a combination of layers of marls, sandstones, and limestones, marked by various unique fossils and organic materials. Sedimentary discontinuities reveal deltaic sequences that exhibit varying sedimentary structures and lithological compositions, reflecting dynamic depositional environments ranging from subtidal to continental. The facies associations within the El Mers Formation are organized into elementary and mesosequences, delineating the transition from prodelta to deltaic plain environments. These sequences capture the evolution of tidal regimes and depositional dynamics.
The shifts in facies and microfauna evolution in our study area reveal intriguing patterns, from the establishment of initial supratidal environments characterized by charophytic marls and ostracod limestones followed by a resurgence of marine conditions, evident from the reappearance of coastal facies and the diversification of ostracod faunas, indicating a significant transgressive phase during the Upper Bathonian–Lower Callovian period. While in the Central High Atlas marine influences ceased by the Upper Bajocian–Lower Bathonian giving way to continental red layers, in the Middle Atlas marine influences persisted until the Upper Bathonian–Lower Callovian boundary, indicating a diachronic filling of the Atlas gulfs towards the Tethyan domain from west to east.
Fossils
= Dasycladales
== Foraminifera
== Ostracoda
== Xiphosura
== Mollusca
== Fishes
== Testudinata
== Crocodylomorpha
== Dinosauria
=Theropoda
Sauropoda
Ornithischia
= Charophyta
== Plantae
=See also
Tafraout Group (Toarcian–Aalenian)
Azilal Formation (Toarcian-Aalenian)
Guettioua Formation (Bathonian–?Callovian)
Anoual Formation (Bathonian)
Ksar Metlili Formation (Tithonian–?Berrasian)
References
Kata Kunci Pencarian:
- Pandemi Covid-19
- Insiden saat Haji
- Vaksin Covid-19 Oxford–AstraZeneca
- Virus dalam sejarah manusia
- SARS-CoV-2
- Fujitsu
- Prancis Vichy
- Konvoi Malta
- Pasar Grosir Makanan Laut Huanan
- Insiden desak-desakan Mina 2015
- El Mers Group
- Attack on Mers-el-Kébir
- Thyreosaurus
- Mers
- Battle of Mers-el-Kébir (1507)
- 2024 in archosaur paleontology
- MERS
- List of African dinosaurs
- MERS-related coronavirus
- Mers El Hadjadj Stadium