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Abstract The Holocene salts deposits in Bahariya Oasis are formed in closed basins and are included the following main types; aeolian sand deposits, and surficial salt deposits which cover nine isolated localities in different parts within in the Bahariya Oasis form about 70 % of the Holocene deposits and occupy low lying areas or basins that are controlled by tectonics. The Holocene salt deposits lie above the Bahariya Formation (Cenomanian, Cretaceous ). The base of this formation is composed of reddish sand and sandstone , the middle part is made up of sand, sandstone , silty clay and shale , and the upper part is composed of silt , clay, shale and sandstone beds. The low laying areas recieve sediments from the surrounding bed rocks (Bahariya Formation , El Hufhuf Formation, Khoman Formation, Naqb Formation, (5. Radwan Formation , or Volcanics) that accumulate in thin planner layers. The detrial sediments brought to closed basins by the inflowing wadies and settle down from suspension and also through wind blown sediments. General field features of the Holocene salt deposits are salt thrust polygons, mud cracks, pressure ridges, adhesion ripples and sand dykes. Temperature always play an important role, not only influences evaporation rate , but also controls the type and sequence of salt and evaporite minerals by increasing aridity , the salinity increases and the depth of the lake decreases leading to deposition of’bedding evaporite minerals. |