Sedimentary features and significance of interdune deposits.

Interdunes occur between dunes in most dune fields. This study indicates that interdunes among dunes formed in unimodal wind regimes are fundamentally different than interdunes among dunes formed in bimodal or complex wind regimes. Interdune deposits among dunes formed in bimodal or complex wind regimes seem to be thicker and more areally extensive than among unimodal dune regimes. Interdunes broadly can be classed as deflationary or depositional; these in turn can each be subdivided, based upon water content, into dry, wet and evaporite interdunes. Sedimentary features of each type are discussed and illustrated. Ancient interdune or sabkha deposits are important for several reasons: 1) they may form barriers to effective fluid migration in hydrocarbon reservoirs or isolate productive intervals; 2) they may be potential hydrocarbon sources; 3) they may be a source of minerals and trace elements; and 4) they may serve as faunal, floral or reference horizons within eolianites. -from Authors