Gypcrete of Kuwait: field investigation, petrography and genesis

Field investigation in the southern part of Kuwait indicated the widespread occurrence of duricrust. Gypcrete is one of the frequently observed types that exists at or near the land surface. Three types of gypcrete are recognized: weakly cemented fibrous gypcrete; hard fibrous gypcrete; and powder gypcrete. Petrographically, several crystal shapes are identified: interlocking anhedral to subhedral crystals, lozenge-shaped; feather like; and poikilotopic crystals. Three integral factors contributed to gypcrete genesis; these are: availability of gypsum, the mechanisms of gypsum translocation from its source to its place of deposition, and favourable conditions under which the mineral can precipitate. In Kuwait, three models are suggested to explain the genesis of gypcrete. The role of duricrust in developing the landscape of Kuwait is well documented but a comprehensive study to assess its role in the sub-surface zones is required.