Ichnology and sedimentology of non-marine Permian red-beds of the Argana Basin (Western High Atlas, Morocco): palaeoecological and palaeoenvironmental implications

The upper part of the Tourbihine Member (T2) of the middle-late Permian Ikakern Formation (Argana Basin, Western High Atlas, Morocco) consists of continental red beds that record alternating wet and dry climatic conditions. Sedimentological analysis indicates deposition within a braided fluvial system, with well-drained overbank fines and predominantly immature paleosols formed under a semi-arid to arid climate characterised by strong seasonality. The T2 red beds yield a moderately diverse ichnofauna, including striated invertebrate burrows (Scoyenia gracilis), simple horizontal cylindrical burrows (Palaeophycus tubularis, Planolites isp.), vertical to subvertical burrows (Arenicolites isp. Skolithos isp.), complex burrows (Sphaerapus larvalis, Spongeliomorpha carlsbergi), locomotion traces (Siskemia elegans), and abundant meniscate backfilled traces, notably Taenidium. These are associated with tetrapod footprints. The ichnofauna, mainly preserved in fine-grained fluvial deposits, represent typical elements of the Scoyenia and Skolithos ichnofacies within continental environments settings. Two distinct ichnoassemblages can be recognised: (1) the Skolithos-Arenicolites ichnoassemblage, reflecting higher-energy conditions, generally associated with intrachannel bar deposits; and (2) Taenidium-Spongeliomorpha ichnoassemblage dominated by a pre-desiccation suite characterised by Taenidium burrows, indicative of a low energy fluvial settings with progressive substrates-drying.