Geochemistry and mineralogy of selected carbonaceous claystones at DSDP Hole 76-534

• Main Authors: Kagami, Hideo, Ishizuka, Toshio, Aoki, Saburo
• Format: Dataset
• Language: English
• Published: PANGAEA 1983
• Subjects: 76-534; Deep Sea Drilling Project; DRILL; Drilling/drill rig; DSDP; Glomar Challenger; Leg76; North Atlantic/BASIN; North Atlantic
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.809830; https://doi.org/10.1594/PANGAEA.809830

Four dominant depositions of carbonaceous claystones are recognized to have occurred during the early Aptian to middle Albian at Site 534. There are correlations of stable isotope ratios with organic carbon content and of clay content with clay mineralogy of the samples. Almost all organic carbon in these sequences has very negative terrestrial isotope ratios, and the clay of that age indicates predominance of aluminous montmorillonite, which is thought to be of terrigenous origin. It is suggested that development of coastal vegetation belts and deltaic outbuilding with consequent outpouring of land-plant detritus and terrigenous elastics into the deep basins probably led to formation of the "black shale" facies.