Assessment of the Feasibility of CO2 Storage in Carbonate Saline Aquifers and Structural Traps in North Oman

Abstract

Petroleum Development Oman (PDO) has set a target to reduce CO2 emissions to net zero by 2050, which is aligned with Oman’s country vision. A mid- and long-term strategy has been developed to identify cost-competitive abatement staircases, including elimination of routine flaring, driving energy efficiency across operating assets and increasing the share of power generation from renewable power sources (solar and wind). Although these activities will lead to a step-change reduction in CO2 emission levels, Carbon Capture, Utilisation and Storage (CCUS) will be a key enabler of PDO’s net zero targets. The extensive Mesozoic carbonate rock sequences of North Oman provide an exciting opportunity for CO2 storage in both dipping saline aquifers and structural traps. While hydrocarbons are produced from these carbonates in numerous fields in the country, they also have enormous potential for carbon storage with multiple reservoir-seal pairs, particularly in the Shuaiba, Kharaib, Lekhwair and Habshan Formations of the Kahmah Group. Unlike the majority of CCS projects globally which utilise clastic saline aquifers and depleted fields, carbonates present an additional challenge due to the pervasive nature of faults and fractures which can exert a large influence on both injectivity potential and containment of the CO2 plume.