Lower Maastrichtian inoceramid bivalves from the Oslen Krivodol section (Western Fore-Balkan, Bulgaria)

Inoceramid data were used to characterize the lower Maastrichtian strata in Western Fore-Balkan (Bulgaria), based on newly discovered Oslen Krivodol section. The upper part of Kunino Formation yielded a well-defined inoceramid-bearing level. A number characteristic taxa make up inoceramid assemblage, including Cataceramus palliseri (Douglas, 1942), C. subcircularis (Meek, 1876), barabini (Morton, 1834), glendivensis Walaszczyk, Cobban and Harries, 2001 Endocostea typica Whitfield, 1880. Additionally, Trochoceramus spp. “Inoceramus” sp. also found. It is, therefore, assumed that both Zone an undetermined (probably lower) radiosus are present is there mixing faunas due low sedimentation rates local submarine washout.