LATE CRETACEOUS PALYNOFLORAS AND FORAMINIFERA FROM AIN-EL-WADI AREA, FARAFRA OASIS, EGYPT

Surface and subsurface Cretaceous sediments in the Ain El-Wadi area, N NE Farafra Oasis have yielded diverse assemblages of palynofloras and foraminifera. The succesion is composed of siliciclastic sediments of the El-Hefhuf Formation which are unconformably overlain by carbonates of the Khoman Formation. Terrestrial palynomorphs are the predominant constituents of the El-Hefhuf Formation in the Ain El-Wadi borehole w hich is dared as late Turonian-Santonian on the basis of the presence of Arecipites spp., Droseridites senonicus, Foveotricolpites giganteus , F. cf. gigantoreticulatus, F. cf. tienabaensis, Liliacidites spp., S cabratriporites simpliformis and other triporate and tricolporate poll en. One new pollen species, Liliacidites farafraensis sp. nov., is des cribed. Deposition of the El-Hefhuf Formation took place in a swamp or marsh environment under the influence of marine incursions for short periods. The white chalk of the Khoman Formation exposed in the Ain El -Khadra section is dated as middle to latest middle Maastrichtian (Gan sserina gansseri and Contusotruncana contusa foraminiferal Zones). An open marine, warm Tethyan outer shelf environment of deposition is inf erred. (C) 1997 Academic Press Limited.