Print this pageProspective Petroleum Systems of the Eritrean Red Sea Basin
HAZLETT, D., G. CHAPMAN, W. MULLER, and D. PARIZEK
The Eritrean Red Sea basin is an Oligocene to Recent extensional feature characterized by multiple discrete episodes of rift-related tectonics and sedimentation. Eight wells (1965-1977) demonstrate the existence of a thick and aerially extensive Upper Miocene salt basin. The pre-salt and post-salt sections are dominated by clastics which generally grade (west-east) from alluvial fan redbeds and fan-delta silts/sands into moderate-deepwater sands into shales. The pre-salt Habab section is age equivalent to the Belayim/Kareem/Rudeis interval which reservoirs nearly 5 BBOE EUR in the Gulf of Suez. The post-salt Desset section has significant gas-condensate tests in offshore Sudan.
New aeromagnetic, gravity and seismic data have been combined with heatflow, structural and basin modeling to define potential oil and condensate plays. The prospective pre-salt petroleum system is interpreted as middle to upper Habab reservoir sands draped over tilted fault blocks, sourced by marine Type II kerogen which expelled 5-2 Ma, and sealed by upper Habab marine shales and/or Amber salt or salt welds. The salt is interpreted to have acted as a "thermal wick", which helped to preserve and thicken present-day oil kitchens, despite the area's generally high (average > 110 HFU) present-day heatflow. Post-salt prospective petroleum systems are interpreted to be located within Upper Miocene intra-diapir, mini-basins containing marine shales. These shales, as well as pre-salt source rocks, are interpreted to source Desset sandstones in salt related traps (e.g., turtle structures, pillows, rollers, diapir flank plays) sealed by evaporites and interbedded shales.