Major and trace elements of basalts and basaltic pebbles at DSDP Hole 75-530A

Project

Leg 75 drilled into igneous basement in the Angola Basin at Site 530, located about 20 km north of the escarpment at the eastern end of the Walvis Ridge. Petrographic and geochemical characteristics of the basalts indicate that the basement is quite uniform, variations in chemical composition being related to weathering, crystal fractionation, and the modal abundances of individual minerals. These basalts are similar to those drilled at Sites 527 and 528 on the central section of the Walvis Ridge, but are less enriched in incompatible elements than basalts dredged from the eastern end of the Walvis Ridge.