Mesozoic to Recent Structural Evolution of the Eastern Rub’ Al-Khali, Saudi Arabia

Gijs C.J. Holstege¹*, Mahdi Al-Mutlaq¹, Joerg Mattner², Fuad Al-Somali¹, Ashraf Khalil¹, and Thomas Connally^1
1SRAK, Saudi Arabia
²GeoTech, Bahrain
*[email protected]

Two main structural trends are evident in the eastern Rub’ Al-Khali Basin: a NNE trend, similar to the dominant structural trend in the United Arab Emirates; and a NS trend, similar to the one observed in the major oil fields of Saudi Arabia. Understanding the interplay between these two trends and their relationship to deep-seated older basement structural components, as well as their Phanerozoic reactivation history, is critical to obtaining a robust exploration risk assessment for these structures in this area. Data used to underpin the structural analysis are regional analogue structural data, 2-D seismic data from eastern Saudi Arabia, and structural observations from core and dip-meter logs. Together with geochemical and stratigraphic analyses this has resulted in a robust kinematic model for the structural evolution of the NS-trending structures. Several phases of structural development have resulted in the present-day composite NS-trending arch-like configurations. The main phase of growth occurred during the Late Cretaceous as a result of NW-SE compression, further phases of growth were recognized during the Late Cretaceous Maastrichtian, Paleocene to Early Eocene, Mid- to Late Miocene and Pliocene times. The rotation of the stress field to a present-day ENE-WSW position for the maximum horizontal stress was recognized through observations from core and seismic data and has resulted in several phases of fracturing, including the reactivation of older fracture systems.

AAPG Search and Discovery Article #90077©2008 GEO 2008 Middle East Conference and Exhibition, Manama, Bahrain