The Impact of the Host Extensional Fabric on the Pre-Salt Sedimentary System and Play Definition, Jizan, Southern Red Sea, Saudi Arabia

M. Mortada¹

Abstract

The southern coast of the Red Sea experienced a significant amount of volcanic activity that affected the basin during the early stages of Tertiary rifting. Despite the fact that the pre-rift clastic sediments — which were invaded by volcanics — have not provided proven hydrocarbon bearing reservoir units, it is evident that the structural fabric that affected the volcanoclastic units (Jizan Group) was key in delineating the pathway of the amalgamated channel system that covered the southern coast of the Red Sea in the Jizan region. The Maqna Group incisions represent a good example of a fluvial to shallow marine channel system that is believed to have created stratigraphic plays controlled by the Jizan group structural morphology. The halite of the Mansiyah Formation provides the classical top seal for the Miocene traps in the Jizan region. Jizan presents a vivid example of downslope salt- mobilization under the loading forces of the overlain column of the Late Miocene-Recent clastic accumulations. Using the 2D seismic data available in the Jizan onshore region, this study sheds light on the interaction between the rift structures and the superseding Miocene sedimentary activities, and its impact on the play type definition in the Jizan region.

AAPG Search and Discovery Article #90188 ©GEO-2014, 11th Middle East Geosciences Conference and Exhibition, 10-12 March 2014, Manama, Bahrain