Foraminiferal Assemblages in the Cenomanian of the Buzet-Savudrija Area (Northwestern Istria, Croatia)

Abstract

In the Cenomanian shallow-water carbonates of Northwestern Istria five biostratigraphic zones have been established:<br /><br />CEN-1 Ovalveolina maccagnoae and Sellialveolina viallii biozone in the early Lower Cenomanian;<br /><br />CEN-2 O. maccagnoae to Chrysalidina gradata interval zone in the late Lower Cenomanian;<br /><br />CEN-3 C. gradata biozone in the early Middle Cenomanian, locally subdivided into two subzones:<br /><br />CEN-3a C. gradata and orbitolinids (lower part)<br /><br />CEN-3b C. gradata without orbitolinids (upper part);<br /><br />CEN-4 C. gradata and Broeckina (P.) balcanica biozone in the late Middle Cenomanian, and<br /><br />CEN-5 C. gradata, B. (P.) balcanica and Vidalina radoicicae biozone in the Upper Cenomanian.