Significantly higher concentrations of carbon dioxide (CO2) have been systematically documented within multiple hydrocarbon fields situated offshore Sarawak, Malaysia. Several hydrocarbon findings in the highly prolific Sarawak offshore region are rendered economically unviable due to elevated levels of carbon dioxide (CO2). Numerous wells and fields within the Central Luconia and west Luconia province have registered substantial concentrations of CO2, exceeding 40% at maximum. Characterizing the distribution of CO2 in this region has been always challenging. To address this, an integrated investigation incorporating geological, geophysical, and geochemical datasets was conducted to elucidate the factors influencing the spatiotemporal variations in CO2 distribution within the region. Various geological factors controlling the genesis and spatial dispersion of CO2 in the investigated locale have been identified and deliberated.
Additionally, a comprehensive three-dimensional basin modeling analysis was carried out, concentrating on the processes of hydrocarbon and CO2 generation, migration, and accumulation. The primary aim of this study was to enhance our comprehension of the origins of CO2 and its prediction which will help in de risking prospects and monetizing stranded high contaminants fields. This novel method employing an integrated Geology and Geophysics (G&G) coupled with a model-based approach has been utilized to produce CO2 concentration and risk maps for the Sarawak Basin. This innovative model enables the inclusion of subsurface geological processes pivotal in the CO2 accumulation within traps. This approach presents a notable advantage compared to the conventional method of extrapolating observed data for generating CO2 concentration and risk maps, especially when predicting beyond the established control points.
