The continental intercalaire of northwestern Sahara and its equivalents in the neighbouring regions

Abstract

A preliminary attention is given to the principal continental formations which are recognized in the northwestern Sahara, and the terminology proposed by Kilian in 1931. Special emphasis is placed on definition of the Continental intercalaire, which corresponds to the formations between the marine Namurian and Cenomanian strata.The series north of the Hoggar are described, in particular the better known and most complete section that occurs in the Algerian-Libyan confines, and constitutes the stratotype described by Kilian.Later is given a description of the series equivalent to the Continental intercalaire in neighbouring regions: the Alpine chain of North Africa, the Tunisian-Libyan confines, the great basins of Libya, Egypt, Taoudenni and Tanezrouft, and lastly the intracontinental basins south and southeast of the Hoggar, from Niger to Sudan. This description shows that the concept defined by Kilian is applicable in many regions; elsewhere, the equivalents are only partial, the continental formations possibly having begun or continued far beyong the stratigraphic limits fixed by Kilian.Paleontologic content of the Continental intercalaire, emphasizing on paleoflora, mollusca and dinosaurs, and sedimentologic features are described; then an attempt is made to reconstruct the paleoclimatic and paleogeographic environments.Magmatic and tectonic events, which eventually influenced the sedimentation of the Continental intercalaire are also mentioned.An addendum outlines the groundwater, mineral and oil resources contained in this complex and its lateral equivalents.