Geological modeling for a carbon dioxide sequestration project in Abu Dhabi

Abstract

Numerous studies have been done in the Shu'aiba Formation, one of the most prolific hydrocarbon intervals of the Middle East, especially in Abu Dhabi, UAE. At present, some geo-modeling studies have been carried in producing oil fields, e.g. the Bu Hasa Field and the Asab Field. However, there has been little attempt to build a regional geo-model of the Shu'aiba Formation across onshore Abu Dhabi to characterize the progradational clinoforms within a regional sequence stratigraphic framework. As a part of the Abu Dhabi CO2 Sequestration (CCS) project, there was a need to build a comprehensive and integrated geological model of the Shu'aiba Formation in the Falaha Sycline. This project integrated available data sets from the Falaha Syncline and from the adjacent oil fields including seismic data, well data and core data in a consistent manner to establish a regional sequence stratigraphic framework and to build a geo-model of the Shu'aiba Formation between the major onshore oil fields. In order to characterize the heterogeneity of the Shu'aiba Carbonate platform, a five-order hierarchical conceptual model of the Shu'aiba Formation that merged sequence and reservoir architecture together was built based on the study of lithofacies, facies assocations (FA)/reservoir rock types (RRT), facies association packages and their corresponding depositional settings in the sequence framework. This conceptual model was used to guide the geo-modeling process. Compared to previous facies models, using single modeling methods, such as Truncation Gaussian Simulation (TGS) and Sequential Indicator Simulation (SIS), this project built the facies model in a hierarchy order based on the hierarchy modeling method, conditioning the 4th-order hierarchy to the 3rd-order hierarchy. Based on the established facies and petrophysical model, the suggested sites for CO2 sequestration are the laterally continuous bound/rudstones from the Thamama Zone A, and the rud/grainstones from the highstand systems tract (HST) in the highstand progradational cycles because of the high reservoir quality (porosity and permeability) and low model uncertainty. With more data, such as three dimensional (3D) seismic and more wells, seismic inversion and multipoint statistics methods can be applied in the future to improve the final model.

Date of Award	2013
Original language	American English
Supervisor	Jorge Salgado Gomes (Supervisor)