Christopher J. Schenk1,
Richard M. Pollastro1
(1) U.S. Geological Survey, Denver, CO
Abstract: Assessment of undiscovered oil and gas resources in the Qusaiba-Paleozoic Petroleum System of the greater Rub ‘al Khali Basin, Arabian Peninsula
The purpose of this study was to assess the potential for undiscovered conventional oil and gas resources in the Rub ‘al Khali Basin of the Arabian Peninsula. On the basis of total discovered petroleum volumes (oil and gas), the greater Rub ‘al Khali Basin as defined here ranks fifth in the world. The Qusaiba-Paleozoic is one of three major petroleum systems identified in the greater Rub ‘al Khali Basin. The Silurian Qusaiba Shale source rock currently is in the gas window throughout much of the basin, and is in the oil window in a band along the southern, western, and northwestern margins of the basin. Using existing fields to the north in central Saudi Arabia as an analog for the southern part of the basin, the reservoirs to the south may be mainly sandstones of the Permian, whereas the reservoirs in the Qusaiba system are mainly Permian carbonates in the northeast. Hydrocarbon traps are mainly associated with basement block faults and regional wrench-fault systems, but stratigraphic traps are also present. Migration was mainly from the Qusaiba along faults into Permian reservoirs. The Qusaiba-Paleozoic Petroleum System has been divided into two assessment units: the Qusaiba Structural Oil Assessment Unit and the Qusaiba Structural Gas Assessment Unit. For each assessment unit a probability distribution was developed for the sizes and numbers of undiscovered oil and gas accumulations using published geology, oil and gas field data, and analog data sets, and a Monte Carlo approach was used to generate distributions of undiscovered resources.
AAPG Search and Discovery Article #90914©2000 AAPG Annual Convention, New Orleans, Louisiana