RT Journal Article
T1 Characterization of the Carnian Pluvial Episode in the Argana Basin (Western High Atlas, Morocco): An approach based on sedimentology, clay mineralogy and paleosols
A1 Tourani, A.
A1 Benaouiss, N
A1 Horra Del Barco, Raúl De La
A1 Fernández Barrenechea, José María
A1 Gallego, O. F.
A1 López Gómez, J.
A1 Bourquin, S.
AB We report on a multi-proxy study of the Carnian Pluvial Episode in the continental Argana Basin (Morocco) based on mineralogy, geochemistry, paleosols and sedimentary features. The study focus on two sections of the Irohalene Member (unit t5) of the Timezgadiouine Formation dated as late Julian-early Tuvalian through clam shrimp (conchostracan) associations. The sedimentary study of the Irohalene Member defines three parts: lower, middle and upper (t5.1, t5.2, t5.3 respectively). The base of the lower part comprises channels with gravel and sandy bars related to proximal areas, and fluvial meandering systems, overbank and floodplain deposits developing upwards. Extensive floodplains showing the development of siliciclastic and carbonate lakes mostly represent the t5.2 and t5.3 parts, although the sedimentary characteristics of the former reflect more humid and permanent water conditions. These more humid characteristics are also indicated by the drastic change from calcareous paleosols in t5.1 to smectitic Vertisols in t5.2, which occur in relation to thin layers of lacustrine carbonates, greenish lutites, and hybrid oolitic sandstones of palustrine environments. Stable carbon and oxygen isotope data are consistent with a general tendency towards the arid conditions observed in the Tadart Ouadou t6 Member of the Bigoudine Formation, of fluvial-eolian origin and younger in age. This general tendency is interrupted by at least two humid yet hot intervals characterized by pedogenic carbonates featuring lighter isotope compositions and lacustrine carbonates precipitated under conditions of high temperatures and evaporation rates.
PB Elsevier
SN 0031-0182
YR 2023
FD 2023-10-01
LK https://hdl.handle.net/20.500.14352/87708
UL https://hdl.handle.net/20.500.14352/87708
LA eng
NO Ministerio de Ciencia e Innovación y Universidades
NO Consejo Nacional de Investigaciones Científicas y Técnicas
DS Docta Complutense
RD 25 ago 2024