Early Carboniferous ‘Non Paleozoic-Type’ Monotaxic Shell Beds From The Northern Arabian Plate (Hakkariçukurca Area, Se Turkey): A New Gondwanian Occurrence

‘Paleozoic-type’ shell beds are accumulations dominated by typical members of Paleozoic fauna, such as articulate brachiopods, bryozoans, crinoids, and ostracodes. Articulate brachiopods are the major component of the Paleozoic fauna, and are the dominant members of many shallow-water marine communities (Li and Droser, 1999; Waisfeld et al. 1999; Gourvennec and Hoşgör, 2012). On the other hand, Early Carboniferous shell beds, including bivalve-only and bivalve-dominated beds are very common in the southern Anatolia, Hakkari-Çukurca region (Fig. 1). Bivalve-rich accumulations provide insight into the role of shell composition and taphonomic resilience in the formation of the typical monataxic shell bed types. In the light of the numerous studies from all aquatic ecosystems, bivalves have been used to reconstruct ancient paleoenvironments from Carboniferous strata from Avalonian or Perigondwanan terranes and Gondwana, encompassing marine shelf through to the nonmarine, coal-bearing strata (Okan and Hoşgör, 2007; Hoşgör et al. 2012). Okan and Hoşgör (2007) and Hoşgör et al. (2012) provided a comprehensive summary of Early Carboniferous bivalve paleoecology directly related to the depositional environments. The purpose of this study is to examine the paleontologic, stratigraphic and sedimentologic aspects of such unique accumulations in order to better understand the characteristics of ‘non Paleozoic-Type’ myalinid bivalv shell beds. Fossil deposits were described considering stratigraphic, sedimentologic, taphonomic and palaeoecologic attributes sensu by Kidwell and Holland (1991). Taphonomic features were observed in fossil fragments larger than 5 mm.