High Resolution Sedimentology and Digital Outcrop Analog Modeling of the Late Triassic Minjur and Early Jurassic Marrat Formations: Implication to Sequence Development and Reservoir Architecture, Central Saudi Arabia

M.S. Osman¹, O.M. Abdullatif¹, H. Eltom¹, M.A. Yassin¹, M.A. Bashri¹, and A.A. Al-Mubarak¹

Abstract

The siliciclastic – carbonate successions of the late Triassic – Early Jurassic of the Minjur and Marrat Formations are commonly recorded within the Saudi Arabia and other countries within the Arabian Peninsula. These successions have been exploration targets for hydrocarbon occurrence and important reservoirs. Outcrop analog studies have improved the understanding and characterization of petroleum reservoirs by overcoming the limitations of subsurface data and techniques. The outcrops of Minjur and Marrat west of Riyadh represent a good outcrop analog. This succession has been investigated utilizing integrated approach using LiDAR (Light Detection and Ranging) digital outcrop modeling, high resolution sequential and chemostratigraphy. The main objective of this integrated approach is to characterize the succession and establish criteria for recognition that might help to recognize facies, stratigraphic heirarchies, and reservoir architecture. Then, high resolution sedimentological and stratigraphical work has been conducted including detailed lithofacies description based on vertical sections, sampling and Gamma-Ray measurement. Elemental chemical analysis was conducted for major, trace and rare earth elements. The sedimentological and stratigraphical field and laboratory results have been superimposed in the digital outcrop model. The model has allowed recognizing and revealing vertical and lateral distribution of lithofacies and their stacking pattern. Resevoir continuity and architecture were also revealed at meso- to macro- (10-100 m) outcrop scale within the succession. The reconstructed model proved to be valuable for understanding and prediction of reservoir quality and architecture within interwell spacing and for the developing and enhancing the economic reservoir productivity.

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