Technical Report
The main aims of the study are to assess the global potential for geological storage of CO₂ in shale and coal formations and the impact of gas production from shales on CO₂ storage capacity in underlying deep saline aquifers by compromising caprock integrity. The study would comprise a comprehensive literature review to provide guidance on the following issues: Global status of hydrocarbon production from shales and CBM and potential effects on CO₂ storage both in the producing shales/ coals themselves and underlying hydrocarbon reservoirs and/or deep saline formations. The focus should be on gas production, but with reference to oil production from shales; Current status of research into geological storage of CO₂ in shales and coals; Potential nature and rate of trapping processes; mechanisms of storing CO₂. CO₂ injectivity into shales and coals, with reference to fracturing practices employed by industry; Containment issues arising from shale fracturing, both for shales as a storage medium per se, and in terms of caprock integrity for underlying storage units, particularly deep saline aquifers; Methods for assessing storage capacities for CO₂ storage in shales and coals; High level mapping and assessment of theoretical/effective capacities; Potential economic implications of CO₂ storage in shales and coals.
