Gas-water-rock interactions in Frio Formation following CO2 injection: Implications for the storage of greenhouse gases in sedimentary basins

Petrophysical analysis to investigate the effects of carbon dioxide storage in a subsurface saline aquifer at Ketzin, Germany (CO2SINK)

“…The X-ray diffraction data from Ketzin sandstones indicate nearly 1% hematite (Norden, 2009), and thin sections indicate partly a ferritic matrix (Kummerow, personal communication). A notably increase in concentration of dissolved Fe (from 30 to 1100 g/l) in sampled brine after injecting supercritical CO 2 into the Frio Formation, Texas USA, was observed by Kharaka et al (2006). They concluded that the increase in Fe and Mn was caused by dissolution of Fe oxyhydroxides.…”

Greenhouse gas mitigation in a carbon constrained world: The role of carbon capture and storage

“…In any case, liability for expected or unexpected leakage is an issue to be debated. Doubts about storage safety have been fuelled by a recent US study showing that stored CO 2 can dissolve minerals in the ground and, by this means, cause leakage (Kharaka et al 2006). Altogether, however, the IPCC 2005 report optimistically states that "the fraction retained in appropriately selected and managed reservoirs is very likely to exceed 99% over 100 years, and is likely to exceed 99% over 1000 years" (IPCC 2005b).…”

Using time-lapse VSP data to constrain velocity-saturation relations

“…This suggests that the friable nature of the reservoir sand can be a source of uncertainty in our modelling. Moreover, the chemical changes reported by Kharaka, et al (2006) can be the cause of a large change in the rock frame properties after injection which we did not take into account in our modelling. This is supported by the shear wave reduction observed by Daley, et al (2008) in the immediate vicinity of the injection well.…”

“…The rock physics model best matches the VSP results using large grain moduli and uniform saturation for fluid substitution. Work reported by Kharaka, et al (2006) has shown that CO 2 injection into the Frio C caused calcite to dissolve from the rock matrix possibly changing the rock frame properties (Hovorka,2009). These chemical interactions are dependent on the reactive surface area, which is largest at the borehole with high CO 2 saturations (Vanorio, et al,2011).…”