Nouvelles observations stratigraphiques sur le Cretace superieur du synclinal de Glandage-Creyers (Drome); repercussions paleogeographiques

Abstract

Abstract New paleontologic data, especially the discovery of Globotruncana concavata (foraminifer) and an Inoceramus (I. sp. ex gr. muelleri) in the gray-blue upper Cretaceous limestones of Glandage-Creyers (Drome, French Prealps), indicate that the limestones are essentially Santonian, possibly extending upward into the lower Campanian. The underlying Gas conglomeratic complex is now assigned to the upper Turonian and, at the top, to the Coniacian. The Gas complex consists of two conglomerate layers separated by sandy limestones. Thus the so-called pre-Senonian orogeny apparently took place in at least two phases, one early Turonian (pre-Senonian), the other late Coniacian (early Senonian). The Coniacian, not the Turonian, is the major phase.