Cenozoic Tihamah Rift Basin, Yemen Red Sea: Geological Setting and Exploration Potential

Abstract

The Cenozoic Tihamah rift basin on- and offshore is developed in the south-eastern part, Yemen Red Sea as a result of rifting process, which started in Upper Oligocene and continue to the recent. The sedimentary successions of the Tihamah rift basin include a thick syn- and post-rift succession of the Tihamah Group with a wide range of depositional environments from marine, transitional and continental origin that related to different stage of structural evolution of the basin. The petroleum system of the Tihamah basin indicate good source rocks mainly the shale and mudstone layers of the Zaydiyah and Maqna Formations and the shale within the Ghawwas Member of the Salif Formation. The sandstone horizons of the Zaydiyah, Maqna, Salif and Abbas Formations provide a good reservoir potential with good porosity and permeability. The evaporites sediments (anhydrite and halite) of the Salif Formation and the Ghawwas Member offer a very good seal. The strong halokinesis, the different thickness of the salt, the lateral and vertical variation of sediment depositions in the basin, intertonguing of volcanic flows and intrusions of dykes and sills of Yemen Volcanic Group and the NNW/SSE structural features between the rift margin and rift center formed the Tihamah rift basin into margin-parallel structural zones, salt walls and pillows, which divided the basin in several sectors with different character. Accordingly, the rollover anticline and the diapir fairways offer the most attractive combination of source, reservoir and seal, whereas the diapir and salt-cored anticline zones are likely to have good source but limited reservoir potential. The massive salt fairway offers limited trapping possibilities and limited source and reservoir rocks. Oil seeps were found in the As-Salif peninsula, migrated crude oil was present in the onshore region of the Tihamah plain (Zeidiye-1, Alpha-1, and Abbas-1 wells) and oil and gas shows in several on- and offshore wells indicate presence of a proven source rocks in several stratigraphic levels and appears to be oil and gas-prone.

AAPG Datapages/Search and Discovery Article #90194 © 2014 International Conference & Exhibition, Istanbul, Turkey, September 14-17, 2014