High Resolution Digital Outcrop Modeling of Upper Khartam Member, Khuff Formation, Central Saudi Arabia

Abstract

The Permo-Triassic Khuff Formation is well exposed on an outcrop belt in central Saudi Arabia. These outcrops represent surface equivalent to Khuff reservoirs in the subsurface. The objective of this study is to reconstruct high resolution digital outcrop model of the Upper Khartam Member of Khuff Formation. The methodology included field and laboratory sedimentological and stratigraphic description, analysis integrated with terrestrial laser scanning (Lidar) of outcrop sections. Seven lithofacies associations were revealed and interpreted to be deposited from subtidal and shallowing upward to surpratidal flat depositional environment. The lithofacies tend to form composite stratigraphic sequences that trending down dip and forming the building blocks of the upper Khartam member. The digital outcrop analog model produced integrated the lithofacis, sequences and their startigraphic hierarchies. The stratigraphic surfaces were accurately picked from the digital model along with the bed thicknesses. Packages of software (Parser, Polyworks and VRGS) were used from the acquisition, processing to the interpretation of the digital model. The models revealed the high resolution stratigraphic surfaces and spatial continuity and architecture of the reservoir and non-reservoir bodies at outcrop scale. These results might provide guides to understand reservoir heterogeneity, quality and architecture within the interwell spacing in the subsurface.