Clay mineral stratigraphy in the Permo-Triassic red bed sequences of BNOC 72/10-1A, Western Approaches, and the south Devon Coast

Abstract

AbstractThe Permo-Triassic red bed sequence penetrated in BNOC Well 72/10-1A, located in the Western Approaches, is divided into eight clay mineral zones. The zones are defined by variations in the clay assemblage in which iron- and magnesium-rich chlorite, corrensite and mica occur. This zonal sequence is matched mineralogically and stratigraphically with the pattern of clay mineral variation recorded from the Permo-Triassic sediments of the south Devon coast, some 500 km distant.