Deep-sea trace fossils and depositional model from the lower Miocene Tiaret Marl Formation (northwestern Algeria)

In this research study, 27 ichnospecies belonging to 18 ichnogenera are described for the first time from the lower Miocene Tiaret Marl Formation (north-western Algeria), which consists of thin-to medium-bedded sand-stones and marlstones, representing deep-sea fan facies. The sandstones contain the following ichnotaxa: Cardioichnus isp., cf. Chondrites isp., Ophiomorpha isp., Ophiomorpha annulata, Ophiomorpha rudis, Palaeophycus isp., cf. Planolites isp., Planolites montanus, Zoophycos isp., Tisoa siphonalis, Helminthorhaphe isp., Scolicia isp., Scolicia prisca, Scolicia vertebralis, Cosmorhaphe isp., Desmograpton isp., Gordia isp., Helminthopsis isp., Nereites isp., Tubulichnium cf. incertum, Urohelminthoida appendiculata, cf. Megagrapton isp., Paleodictyon minimum, P. strozzii, P. majus, P. (Glenedictyum) miocenicum and P. maximum. The given ichnoassemblage is recorded for the first time from the Miocene of Algeria and assigned to the Nereites ichnofacies, which is typical of marine bathyal depth.

Automated summary

This research study describes 27 ichnospecies belonging to 18 ichnogenera for the first time from the lower Miocene Tiaret Marl Formation in north-western Algeria. The ichnofacies identified in the sandstones represent a deep-sea fan environment, which is typical of marine bathyal depth.