GEOLOGICAL 3D STATIC MODEL OF BAHARIYA FORMATION (UPPER ALBIANCENOMANIAN), SHAHD/SHAHD SE FIELDS, NORTHERN WESTERN DESERT, EGYPT

Abstract

In 2005, the importance of East Tiba Sub-Basin was highlighted since the oil was commercially discovered for the first time in the Upper Albian Lower Bahariya sandstones. All the used available subsurface data including cores, sedimentary structures, lithological characters, wireline logs signature, petrophysical parameters and biostratigraphy have revealed that, the Lower Bahariya reservoir sandstones are represented by three main stacked tidal channels that were deposited in marginal marine possible tidal-dominated estuary depositional environment. A regional conceptual depositional model has been constructed covering the development leases and surrounding areas to understand the distribution of the sandy facies, their own petrophysical characters and related production behaviour. The model explained the inter-tonguing relations between the relatively low sand qualities (distal facies), less oil productive reservoir sands of the Shebl area sands and the good quality (proximal facies), more oil productive reservoir sands of the SE located marginal marine tidal channels of Shahd/Shahd SE Fields. A 3D reprocessed PSDM seismic cube has been used in addition to the well data to produce the Bahariya structure map as it represents a good seismic marker allover the study area. The play concept in the study area is a threeway dip closure along NW trending Cretaceous faults having enough throw (+/600 ft.) to bring the Abu Roash “G” shales in the down-thrown side to juxtapose the Lower Bahariya reservoir sands in the up-thrown side.