Trace fossil analysis of sandy clastic contouritic deposits in the late Miocene Rifian Corridor (Morocco): Ichnotaxonomical and palaeoenvironmental insights

Abstract

Ichnological analysis was conducted in the late Miocene sandy clastic contouritic deposits from the Rifian Corridor (Morocco). The Rifian Corridor was a main gateway between the Mediterranean Sea and the Atlantic Ocean during the late Miocene. An initial detailed ichnological analysis of clastic contourite facies revealed trace fossil assemblages of high abundance (similar to that of calcareous contourites) and low ichnodiversity. Parahaentzschelinia and Rosselia were registered for the first time in contouritic facies. Scolicia and Macaronichnus were found to be the dominant ichnogenera in the studied sandy clastic contourites. Abundant Macaronichnus, Parahaentzschelinia and Scolicia evidence the adaptation of trace makers to “unfavourable” energetic conditions, food availability being a major parameter that favoured opportunistic colonization of the supposedly “un-inhabitable” high-energy contourite depositional setting. Similar ichnological studies conducted in selected outcrops will allow us to address the representative ichnoassemblage of coarser (silty/sandy) clastic contourites.