Contact Metamorphism of Kerogen in Sediments from Leg 41: Cape Verde Rise and Basin

Abstract

Six samples from Leg 41 of the Deep Sea Drilling Project were acquired for the purpose of studying the contact metamorphic effects of an igneous intrusion on organic-rich Upper Cretaceous shales (Baker et al., this volume). These samples provide an opportunity to investigate the petroleum convertibility of kerogen from the Cretaceous black shale which has been encountered in a number of North Atlantic DSDP sites. Oil-generating organic matter is common in many of the black shale samples, but always at maturities insufficient for hydrocarbon generation. One sample represents Upper Cretaceous black shale in an immature state from Site 367 in the Cape Verde Basin and is analyzed for control purposes. The remaining five samples are from the Upper Cretaceous black shale sequence at various distances immediately below a diabase sill at Site 368 on the Cape Verde Rise (Figure 1).