SUR LA NATURE ET L’ORIGINE DE LA CROUTE GYPSEUSE DITE «DEB DEB» DANS LES PALMERAIS DE L’OUEST DES ZIBAN

Abstract

In the western area of Ziban, a hardpan crust called localy deb deb was developed. The works, who reported this crust, always showed confusion to its composition. After having reviewed the archive data relating to this formation, we show that it is a crust gypsum deposits at water table level. It was developed in sediment containing calcareous silt and quartz sand that are invaded by the gypsum, following evaporation of the water table, resulting in disintegration and dilution of the primary material.