2 Battelle Memorial Institute, Columbus, OH, 43201

The Michigan basin is an elliptical, Cratonic interior basin extending over approximately 100,000 square miles and consisting of up to 16,000 ft of mostly Paleozoic sedimentary strata. The Midwest Regional Carbon Sequestration Partnership (MRCSP), one of seven regional CO₂ sequestration partnerships funded by the USDOE has concluded an initial (Phase I) geologic assessment of the geological carbon sequestration potential in a seven-state region including the Michigan basin. Substantial sequestration potential was found in the region with the largest potential targets identified in several regional saline aquifer formations. Because of the dramatic increase in density of CO₂ between 1000 and 1500 psi optimal saline aquifer sequestration targets occur at depths in excess of approximately 800m-1000m (2,600ft-3200ft). The late-Early Devonian Sylvania Sandstone and related strata occurs at or just below these depths throughout most of the central Michigan basin and was estimated to contain as much as 15 gigatonnes of CO₂ sequestration potential.

Regional lithologic variations within the Sylvania Sandstone and related strata are known mainly from the analysis of geophysical logs. The Sylvania Sandstone is typically a very porous unit that consists of dolomitic to cherty, fine- to medium-grained, well-sorted and rounded; quartzose sandstone in central and southeastern Lower Michigan but grades into cherty, sandy carbonate to the north and west. The Sylvania, along with the underlying Bois Blanc and Garden Island Formations, overlies the base Kaskaskia unconformity in complex regional stratigraphic relationship and provides substantial regional CO₂ sequestration potential. A USDOE funded, pilot CO₂ injection project has been proposed targeting the Sylvania and related strata in northern Lower Michigan in order to evaluate lithology, petrophysics, and saline aquifer sequestration potential of the Sylvania Sandstone and related strata in this area.

AAPG Search and Discovery Article #90059©2006 AAPG Eastern Section Meeting, Buffalo, New York