Sequestration of CO2 in geological media: criteria and approach for site selection in response to climate change

Anthropogenic effects on climate can be mitigated through various measures, among them being CO2 sequestration in geological media. Geological sinks f or CO2 do not really need any major technological development because the t echnology has already been developed and applied by the upstream energy ind ustry for hydrocarbon exploration and production. The challenge is rather t o identify the best methods and sites for long term CO2 sequestration. Ther e are various ways to sequester CO2 in geological media: utilization in EOR operations, disposal in disused oil and gas reservoirs, replacement of met hane in coal beds, injection in deep saline aquifers and storage in salt ca verns. Several criteria have to be considered when evaluating the potential of a sedimentary basin for CO2 sequestration: its tectonic setting and geo logy, the basin geothermal regime, the hydrodynamic regime of formation wat ers, the hydrocarbon potential and basin maturity, economic aspects relatin g to access and infrastructure and socio-political conditions. The range of sedimentary basins suitable for CO2 sequestration is significantly reduced if these criteria and climatic conditions, accessibility, infrastructure a nd cost of CO2 capture and injection are taken into account. A systematic a pproach is proposed for the assessment and selection of method and sites fo r CO2 sequestration in geological media. (C) 2000 Elsevier Science Ltd. All rights reserved.