Seismic Stratigraphy of the Offshore Nile Delta

Tom Kilenyi, Philip Trayner, Mark Doherty, George Jamieson

The seismic stratigraphy of the offshore Nile delta has been established using a 10,000-km Merlin reprocessed regional seismic database.

This paper focuses on the Neogene interval in which three major seismic super sequences have been recognized. The oldest (super sequence A) is a thick sheet unit of middle Miocene age composed of marine shales and sandstones, affected in places by shale diapirism. The upper super sequence, of Pliocene age (C), is characterized by progradation complicated by both slumping and faulting. These sediments represent deposits from the present Nile delta system, a relatively recent event. Between super sequences A and C lies a thin upper Miocene-lowermost Pliocene unit (super sequence B). This unit can be divided into three sequences, the upper and lower of which (Abu Madi and Oawasim Formations, respectively) are characterized by widespread channeling. The intermediate Messinian sequence, co monly evaporitic, may also be associated with channeling episodes. Potential hydrocarbon plays exist in all three super sequences, and varied trapping mechanisms may be invoked. Dip closures are associated with both rollover on listric normal faults and shale diapirism. Stratigraphic trap potential involves both truncation of C beneath B, occasionally associated with severe angular unconformity, and super sequence B channeling. The Abu Madi channel-fill sand bodies form the primary exploration target.

Despite only 12 offshore wells drilled, there have already been gas discoveries (Abu Qir field, Naf-1 well) which, together with recent changes in Egyptian hydrocarbon legislation, make this region an attractive exploration province.

AAPG Search and Discovery Article #91032©1988 Mediterranean Basins Conference and Exhibition, Nice, France, 25-28 September 1988.