In the efforts to mitigate the unprecedented anthropogenic carbon dioxide presence in the atmosphere, the decision to store this greenhouse
gas in geologic repositories has received global appreciation with assured technical and financial viability. The implication is that the
injection temperature of flue gas in the potential geologic sites will be typically those encountered in combustion power plants. This,
obviously has a geomechanical consequence considering the fact that heat transferred from the aquifer to the low permeability cap rock will
cause excessive pore pressure build up due to poor pore pressure diffusion characteristics of these rocks. While these low permeability
rocks are required to provide stratigraphic trapping mechanisms such excessive pore pressure build up can result in compromising the
geomechanical integrity. This article has used heat transfer theories and geomechanical concepts to obtain steady state temperature
distribution in cap rocks for temperatures ranging from 50 to 8000C. In so doing, cap rock critical temperatures for tensile and shear failures
have been established for a potential on-site gas injection into saline aquifers.
Key words: Carbon dioxide, tensile failure, shear failure, steady state, geosequestration, diffusivity, thermophysical
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