Sedimentology, ichnology and mineralogy of the Upper Bahariya Formation, Western Desert, Egypt

The Upper Bahariya Formation in the Western Desert, Egypt was deposited on a broad tidally influenced mixed siliciclastic-carbonate ramp on the southern margin of the Neotethys seaway. Analysis of twelve cored intervals focusing on the ichnology, sedimentology and the nature of glaucony suggest these strata were deposited in an interdistributary bay prior to a major marine transgression.; The siliciclastic portions of the Upper Bahariya Formation are interpreted as crevasse splay, tidal flat and distributary mouth bar sandstones; while silts and muds are interpreted as interdistributary bay, marsh and overbank levee deposits. The characteristics of autochthonous glaucony and carbonate facies provide evidence of two scales of flooding events.; Analysis of the occurrence and distribution of glaucony within an ichnologic and sedimentologic framework in the Upper Bahariya Formation provides an invaluable tool that enhances the development and understanding of the depositional model.