New findings of ichnofossils in the Bagovskaya formation (Lower Jurassic) of the Western Caucasus

Abstract

An ichnofossil association is established in the shales of the Bagovskaya Formation (Lower-Middle Toarcian, Lower Jurassic) in the southern periphery of the town of Guzeripl’ (Republic of Adygeya). It includes Megagrapton irregulare Ksiazkiewicz, 1968, Helminthopsis isp. and ? Chondrites isp.; also Planolites isp. is present in some layers. This association characterizes the Nereites ichnofacies (probably, Paleodyction subichnofacies) and indicates the turbidite sedimentation at the foot of the continental slope. The findings of trace fossils allow the conclusion about unstable character of oxygen depletion on the studied territory. The rapid change of depositional environments interpreted on the basis of ichnofossils findings influenced negatively on marine paleoecosystems. The established locality of trace fossils is also of geoconservation and geotourism importance, and it can be used for the purposes of educational excursions.

Keywords

• следы жизнедеятельности
• баговская свита
• аноксия
• западный кавказ
• тоарский ярус