Print this pageAAPG ANNUAL CONFERENCE AND EXHIBITION
Making the Next Giant Leap in Geosciences
April 10-13, 2011, Houston, Texas, USA
Reservoir and Caprock Assessment Using Existing Seismic and Well Data for CO2 Geologic Sequestration in the South Georgia Rift Basins of the Lower Coastal Plain, South Carolina
(1) Earth Sciences and Resources Inst., University of SC, Columbia, SC.
(2) Earth and Ocean Sciences, University of SC, Columbia, SC.
Carbon capture and storage, both terrestrial and geologic sequestration of carbon dioxide (CO2), is receiving attention with governments and private industry around the world. The area of investigation for possible geologic sequestration of CO2 is located in the lower Coastal Plain of South Carolina where the NETCARB Atlas has designated this portion of the South Georgia Rift (SGR) as a saline reservoir. Prior to this study, very little data existed for this part of the SGR. There are 1980’s vintage seismic data collected in Dorchester, Charleston and Berkeley counties to study the origin of the Charleston earthquakes with one wildcat oil well (Norris Lightsey #1) drilled to a depth of approximately 4,000 meters . In order to determine if the SGR is suitable for CO2 sequestration, there has to be sufficient reservoir rock to inject the CO2 into and competent caprock to contain the CO2 from reentering the atmosphere. The hypothesis is the Triassic rift sediments are thick enough to provide adequate amount of reservoir rock. Several intrusive diabase sills/basalt flows observed in the Norris Lightsey #1 and other wells that intrude at different stratigraphic intervals would provide a competent caprock. The primary objective is to use seismic reflection and available well data to identify possible caprock and reservoir intervals and determine the aerial extent of these intervals. In addition, the characterization of any tectonic features that may compromise the integrity of the possible caprock, and to determine if the structural style of the SGR is mainly small subbasins delineated by border faults or rather larger, more continuously extensive basins. Previous work suggested that a basaltic/diabase layer known as the “J” horizon was prevalent over a large area of the SGR. Recent review of existing well and seismic data conclude that in the study area, the ‘J’ horizon is not as widely spread as previously thought. The additional ~240 km of 2D seismic data has shed light on the aerial extent of the “J” horizon as well as any other diabase intrusive layers within the SGR that can be correlated to the well data. With the new information provided by the additional 240 km of 2D seismic data, a potential injection site will be picked.