A geocellular modelling workflow for partially dolomitized remobilized carbonates: an example from the Hammam Faraun Fault block, Gulf of Suez, Egypt

Corlett, Hilary, Hodgetts, David, Hirani, Jesal, Rotevatn, Atle, Taylor, Rochelle ORCID: https://orcid.org/0000-0002-3675-1530 and Hollis, Cathy (2021) A geocellular modelling workflow for partially dolomitized remobilized carbonates: an example from the Hammam Faraun Fault block, Gulf of Suez, Egypt. Marine and Petroleum Geology, 126. 104831. ISSN 0264-8172

Preview

Accepted Version Available under License Creative Commons Attribution Non-commercial No Derivatives. Download (10MB) | Preview

Abstract

Constructing geocellular models of carbonate rocks using standard software is challenging since most of modelling packages are designed, first and foremost, to represent siliciclastic depositional systems, where rock properties are strongly facies-controlled. The distribution and components of carbonate depositional facies vary drastically across the geological timescale as a result of paleoclimate and its effects on carbonate-producing biota. Furthermore, reservoir architecture is less strongly controlled by depositional environment than in clastic settings, and rock physical properties, including fracture networks, are controlled by both primary components and their subsequent diagenetic alteration. This means that rock property distribution is less predictable than in siliciclastic systems, and less well represented by geocellular models that are designed to represent sedimentary architecture. In other words, in carbonate systems, the depositional and diagenetic history needs to be reconstructed in order to successfully model reservoir properties. In this study a geocellular model was created by using a well-characterised outcrop analogue obtained from the Hammam Faraun Fault (HFF) Block, located on the eastern coast of the Gulf of Suez in Sinai, Egypt. This model integrates sedimentological, petrophysical, diagenetic, and structural information into a single database. The workflow utilizes the regional tectonic history, upscaled lithological logs, and two-stage facies modelling (reflecting in and ex situ depositional facies) and resulted in the creation a realistic model of remobilized carbonates that were deposited on the slope of a carbonate platform during a period of tectonic instability. Diagenetic overprinting was achieved using probability functions to reflect the history of burial, rifting, and the spatial relationship of stratabound and non-stratabound dolostone bodies. The study demonstrates a workflow for modelling mass-transport carbonate facies and multistage fault-related diagenesis so that flow controlling facies and diagenetically altered poroperm and fracture networks are accurately represented using commercially available modelling software, and in particular demonstrates how diagenetically controlled geobodies can be captured using simple algorithms.