Clay mineralogy of Cretaceous and Cenozoic sediments off the Moroccan margin, Deep Sea Drilling Project sites 415 and 416.

Abstract

The Tithonian and L Cretaceous turbidites are chiefly marked by the presence of micaceous and chloritic minerals, resulting from tectonic rejuvenations during the oceanic widening. Cretaceous and Paleogene sediments contain abundant well- crystallized smectite, mainly inherited from continental soils developed in poorly drained areas. This suggests a hot seasonally humid climate as does the fibrous clays developed during two periods, attapulgite during the early Aptian, attapulgite and sepiolite during the early Eocene. During the late Cenozoic, the increase of primary minerals and the reappearance of mixed-layer clays and associated non-clay minerals reflect a progressive and irregular worldwide cooling.-from Authors