Jebel Tekzim Formation: Microfacies Analysis and Paleoenvironment Reconstruction (Central Jebilet, Morocco)

Abstract

North of Marrakech, the Hercynian massif of Jebilet is part of the Moroccan Meseta, which lies between the Rif and High Atlas Mountain ranges. It is a segment of Paleozoic age oriented in a submeridional direction, with a length of approximately 170 km and a width ranging from 7 to 40 km. This massif forms a collection of hills and rocky plains, folded and metamorphosed, with moderate relief. To the east of the village of Sidi Bou-Othmane, we find the Jebel Tekzim formation. It consists of carbonate deposits with a thickness of over 80 meters. This formation is deposited on turbiditic formations with a discordant contact, which can be interpreted as a paleogeography. These formations are of Upper Visean age, as indicated by the presence of foraminifera species such as Koninckopora tenuiramosa and Endothyra bowmani. Within these formations, and after analyzing the microfacies from levels C1 to C8, it is evident that the assemblage is characterized by an abundance of fragmented and reworked remnants of bryozoans, crinoids, echinoderms, ooids, bivalves, and less commonly gastropods. These elements are bound together by a cement of sparite and microsparite, indicating a depositional environment that predates reef formation, except for the final level, which is characterized by larger-sized elements such as gastropods and bivalves. This suggests a regressive phase, indicating a shift towards a lagoonal depositional environment.