Premium
Identifying diagnostics for reservoir structure and CO 2 plume migration from multilevel pressure measurements
Author(s) -
Strandli Christin W.,
Benson Sally M.
Publication year - 2013
Publication title -
water resources research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.863
H-Index - 217
eISSN - 1944-7973
pISSN - 0043-1397
DOI - 10.1002/wrcr.20285
Subject(s) - plume , buoyancy , geology , pressure gradient , anisotropy , hydrostatic pressure , isotropy , hydrostatic equilibrium , petrology , mechanics , petroleum engineering , meteorology , optics , oceanography , physics , quantum mechanics
Important to large‐scale implementation of Carbon Capture and Sequestration is the ability to monitor the carbon dioxide (CO 2 ) that has been injected underground. The focus of this study is to understand how flow processes during CO 2 injection impact the pressure observed at a nearby monitoring well. In particular, we are interested in how the reservoir structure (layering and anisotropy) and CO 2 plume migration influence the pressure transients at different depths. For a multilayered geologic model, four basic combinations of homogeneity/heterogeneity and isotropy/anisotropy conditions are examined. Numerical simulations using TOUGH2 show different CO 2 plume migration and large pressure buildups in the storage reservoir and the seal for each scenario. Pressure buildups normalized to the pressure buildup at the depth of injection are diagnostic of the approximate height of the CO 2 plume and provide information on the reservoir structure. Vertical pressure gradients normalized to the initial hydrostatic pressure gradient are diagnostic of reservoir structure soon after the start of injection. Over time, they provide information on the height of the CO 2 plume. The diagnostic features in the pressure response are evident long before the CO 2 arrives at the monitoring well and can be attributed to buoyancy induced and gravity segregated aqueous flows caused by the advancing CO 2 plume. The identified diagnostics will aid in the ultimate goal, which is to develop a monitoring technique based on multilevel pressure measurements.