First records of trace fossils from the Lake District, southwestern Turkey

Abstract

Important new ichnological data was obtained from the Isparta Çay Formation (Triassic to early Cretaceous), Koçtepe Formation (middle Paleocene to Early Eocene), Isparta Formation (Early to Middle Eocene) and I·ncesu Formation (Middle Eocene to Early Oligocene). These formations are significantly exposed in the Eǧirdir, Gönen and Isparta regions within the northern part of the Isparta Angle. An overview of the stratigraphy and its trace-fossil bearing formations and microfossil content is presented together with recommendations. The density and diversity of trace fossils vary between and within these formations, which originated in deep-marine shelf slope and shelf environments of the Neotethys ocean. Changes in the frequency of abrupt turbiditic deposition, oxygenation of the bottom water and possibly food availability are reflective in the trace fossil distribution. The trace fossils of the Isparta Çay, Koçtepe and Isparta formations are typical of deep-marine settings with occasional high-energy turbiditic conditions. The Isparta Çay Formation (Paleodictyon ichnosubfacies) is seen as the bedrocks of the region, whereas the Isparta Formation (Ophiomorpha rudis ichnosubfacies) overlies conformably the Koçtepe Formation (Nereites and Arenicolites ichnofacies). The Ýncesu Formation is laterally interlaced with the Isparta Formation. A high diversity of trace fossils occurs in the Ýncesu Formation (Zoophycos ichnofacies), which was formed in an outer shelf environment. Findings from previous ichnological investigations in Turkey are compiled and compared with the present results from the Isparta Angle.