MICHCAR: A Geological Carbon Sequestration Research Center for Michigan: Saline Reservoir, GCS Storage Resource Estimates for the Michigan Basin
MICHCARB was established at Western Michigan University as a geological carbon sequestration (GCS) research and education center in conjunction with the acquisition and archive of subsurface geological samples at the Michigan Geological Repository for Research and Education. Part of this program comprised evaluation of subsurface data related to injectivity, storage potential, and containment in saline reservoirs and GCS storage resource estimates (SRE) were developed. Prospective reservoir and confining layer, GCS systems in Michigan were initially identified using conventional well data and previous studies; however, a key methodology included reservoir/confining zone characterization through correlation/calibration of well log data with core samples. Direct petrophysical measurements and petrographic analysis provided refined characterization including reservoir rock pore types, effective porosity, injectivity, and confining zone mechanical and break-through pressure. The most important GCS reservoir formations in the Michigan basin are the Lower Paleozoic Mount Simon and St. Peter sandstones, and the Middle Paleozoic Bass Islands dolomite and Sylvania Sandstone. These units comprise nearly 100 billion metric tons (Gt) of GCS potential in Michigan. The Upper Ordovician Utica Shale is a thick (>50 m) mostly argillaceous, primary confining layer for Lower Paleozoic GCS targets. Middle Devonian, evaporite-prone strata of the Lucas Formation (∼100-300 m thick) confine Middle Paleozoic saline reservoirs. The Mount Simon has variable reservoir quality characteristics in the Michigan basin dependent on sedimentary facies variations and depth-related diagenesis. SRE are in excess of 41 Gt with the majority in the southwestern part of the state, although substantial GCS storage capacity is also present in southeastern Michigan. The St. Peter ranges in thickness from a regional stratigraphic pinchout to more than 335 m and occurs at depths greater than 800 m to over 3.35 km throughout the Lower Peninsula of Michigan. SRE are from 15 to 50 GT of CO2 using various methodology and confidence intervals. The Upper Silurian Bass Islands dolomite is a significant GCS target in the central Michigan basin and has SRE of nearly 1.5 Gt. Distinct sandstone and porous, cherty dolomite of the Middle Devonian Sylvania Sandstone defines a northwest to southeast oriented depositional fairway in the central Michigan basin. Using various assumptions, SRE are from 1.9 Gt, considering only conventional reservoirs and 4% storage efficiency, to 7.2 Gt considering combined conventional and unconventional, low permeability tripolitic chert rock types and10% storage efficiency.
AAPG Datapages/Search and Discovery Article #90195 © 2014 Eastern Section Meeting, London, Ontario, Canada, September 27-30, 2014