New Data on the Cenomanian-Turonian Boundary Oceanic Anoxic Event in the Biyuk-Karasu River Section (Central Crimea)

摘要

Cenomanian-Turonian organic-rich clays deposited under periodic anoxic conditions in the basins of that time are recorded in carbonate sections. Cenomanian-Turonian boundary deposits were studied in the Biyuk-Karasu River section (Central Crimea). Dark organic-rich clays were found to intercalate with carbonate-poor clays in the formation during oceanic anoxic events. Mixed type II-III kerogens are abundant in these black beds which constitute oil source strata that are similar in their mineral assemblages but different in their organic matter contents.