Albian–Cenomanian Radiolarian Assemblage from the Smaginsk Formation, the Kamchatskii Mys Peninsula of Eastern Kamchatka

摘要

The Albian–Cenomanian sediments belong to the oldest deposits bearing fossils in the Eastern Kamchatka. Described in this work is one carbonatecherty section of the Smaginsk Complex in the Kam chatskii Mys Peninsula. Two interlayers enriched in sapropelic organic matter represent a peculiar feature of the studied section. The interlayers originated most likely under the influence of Cretaceous anoxic events. All radiolarian taxa identified formerly and now in rocks of the Smaginsk Complex are considered. New data clarify the taxonomic composition of radiolarian assemblages, characterizing the Smaginsk Complex. Some of the currently defined radiolarian species were known before only from the DSDP Sites in the Pacific Ocean. According to data of radiolarian analysis, the section part sandwiched between two interlayers enriched in organic matter is attributed to the Cenomanian. The early Cenomanian age is suggested for one of the studied samples.