Geological sequestration of anthropogenic carbon dioxide in the western Canada sedimentary basin: Suitability analysis

Geological sequestration of anthropogenic carbon dioxide is a potential solution to the release into the atmosphere Of CO2, a greenhouse gas thought of as significantly contributing to the global warming trend observed since the beginning of the industrial revolution. Basically, CO2 can be sequestered in geological media: 1) through enhanced oil recovery (EOR), 2) by storage in depleted oil and gas reservoirs, 3) through replacement by CO2 of methane in deep coal beds (ECBMR), 4) by injection into deep saline aquifers, and 5) by storage in salt caverns. Criteria in assessing the suitability of a sedimentary basin for CO2 sequestration are: a) tectonism and geology, b) the flow of formation waters and geothermal regime, and c) the existence of storage media (hydrocarbon reservoirs, coal seams, deep aquifers and salt structures). Generally, the Western Canada Sedimentary Basin is suitable for CO2 sequestration by all means because it is tectonically stable, it has regional-scale aquifers confined by aquitards or aquicludes, and it has oil and gas reservoirs in various stages of depletion, uneconomic coal seams, and extensive salt beds. However, various regions in the basin have different degrees of suitability, ranging from not suitable along the eastern edge of the basin, to extremely suitable in southwestern and central Alberta. Most major CO2 producers, such as power plants and refineries around Edmonton, are found in regions that are unsuitable for CO2 sequestration in geological media; however, some, such as the oil sands plants in the Athabasca area, are in regions that are not suitable. This analysis of the suitability of the Western Canada Sedimentary Basin for CO2 sequestration in geological media should provide industry and governments with essential information needed for developing plans and policies in response to climate change effects of anthropogenic greenhouse gas emissions into the atmosphere.