The Gorgon Project is a major LNG development to be based in Northwest Australia. Gas will be produced from several offshore gas fields located in the Greater Gorgon Area with processing facilities to be located on Barrow Island. The reservoir fluids of several of the fields contain carbon dioxide (CO2) which will be extracted from the produced gases prior to liquefaction into LNG. The Gorgon Joint Venture participants have proposed to geologically dispose of the produced reservoir CO2 from the gas processed at the Barrow Island LNG plant.
The CO2 injection project was extensively documented and subjected to public comment as part of the Gorgon Project Environmental Impact Assessment Process. Following this process the WA Environmental Protection Authority found that the environmental risks associated with the CO2 injection project were acceptable and recommended that CO2 injection must proceed as an integral component of the Gorgon Project.
The target formation for geological disposal of this carbon dioxide is the Dupuy Formation, a Jurassic saline reservoir, deep beneath Barrow Island. The evaluation of the Dupuy Formation for the disposal of carbon dioxide was focused on characterising the reservoir and narrowing subsurface uncertainties not addressed by legacy oil exploration and development. Data acquisition was targeted to reduce major subsurface uncertainties including a seismic pilot to assess acquisition methods (including 4-D seismic) and an extensively evaluated appraisal well. Robust geological description, hydrodynamic, static and dynamic reservoir models have been used to gauge the impact of CO2 injection on development decisions. Key drivers for this development have been maximising per well injection of CO2 and ensuring containment of CO2 within the reservoir. Through effective subsurface and economic evaluation, a phased and flexible development plan for CO2 disposal has been developed to meet these objectives.
Introduction
The Gorgon Joint Venture is an unincorporated joint venture of three major international oil companies; Chevron (Operator, 50% interest), ExxonMobil (25%) and Royal Dutch Shell (25%). The Gorgon Project is a major capital LNG project that will produce gas from several offshore fields in the Greater Gorgon Area, off the Northwestern coast of Australia. Figure 1 shows the development plan for the Gorgon Project.
The Gorgon and Io/Jansz gas fields will be developed initially as a subsea development with a tie back to Barrow Island. On Barrow Island the raw gas will be received and undergo liquefaction into LNG for export. Production of gas is also being actively considered for supply into the West Australian domestic market. The Gorgon Project has needed to overcome several technical challenges during the concept selection phase of development:The project has one of the longest sub-sea tie-backs in the world (145kms) in water depths greater than 1km and challenging terrain with the pipeline crossing the continental shelf;Barrow Island is a remote location and a Class A Nature Reserve;The nearest major logistical staging point (Perth, Australia) is over 1200km away from Barrow Island;Strict quarantine barriers to prevent environmental contamination;Finally, the Gorgon gas field has a significant component of CO2 in the reservoir fluid composition, with approximately 14% of Gorgon reservoir fluids being CO2.
Tengiz is an isolated Paleozoic carbonate build-up located in the Pricaspian Basin, Republic of Kazakhstan. The reservoir contains over 26 Billion Barrels OOIP and is one of the world's deepest supergiant fields. The introduction of petrophysical rock types (PRT) and pore type classification has significantly improved oil in place estimation and reservoir characterization of this complex carbonate field.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.