Cape Fear Formation, South Carolina Coastal Plain
General Setting
The South Carolina coastal plain consists of a seaward-dipping and seaward-thickening wedge of Cretaceous through Pleistocene sediments. Most stratigraphic units outcrop in belts generally parallel to the coast, where they receive precipitation, which then infiltrates and flows downdip to become ground water. South Carolina receives abundant rainfall, and a number of the shallow aquifers provide ample domestic and industrial water.
Information Search and Selection
The deeper portions of the eastern coastal plain are the focus of this investigation because this area contains strata that are sufficiently deep, porous and permeable, and hydraulically isolated from fresh-water aquifers to make potential CO2 sequestration targets. This area was identified to explore for a potential target for capture and storage of CO2 from industrial activities in this region. However, depth to basement in eastern South Carolina is shallow, largely because of the Cape Fear Arch to the north (Manheim and Horn, 1968; Colquhoun and others, 1983; Aucott and others, 1987; Miller, 1990), which limits the area within South Carolina where aquifers are sufficiently deep to be candidates for CO2 sequestration.
The subsurface of this area has been moderately characterized, but deep aquifers are poorly known because shallow aquifers generally provide sufficient water. There is very little potential for hydrocarbon production along coastal South Carolina, and because the state currently has laws prohibiting subsurface liquid waste disposal, there has been little subsurface research related to petroleum exploration and subsurface disposal of industrial liquid wastes.
Because the basement is so shallow in eastern South Carolina, the only potential candidate for CO2 sequestration is the Upper Cretaceous Cape Fear Formation, which directly overlies the igneous/metamorphic basement in the region (Manheim and Horn, 1968; Colquhoun and others, 1983; Aucott and others, 1987; Miller, 1990). Farther south, in eastern Georgia, the depth to basement is greater, and, therefore, many of the data presented later extend into this region. Note that the aquifer unit described later is referred to by several names in the literature: some call it Cape Fear Formation (Manheim and Horn, 1968; Aucott and others, 1987), others call it Middendorf Formation (Colquhoun and others, 1983), and other regional studies assign it a symbol, such as A4 or Unit E (Brown and others, 1979; Miller and others, 1986). Miller (1990), in his regional study, referred to this interval as the Black Warrior River aquifer.
References
Aucott, W. R., 1988, The predevelopment ground-water flow system and hydrologic characteristics of the Coastal Plain aquifers of south Carolina: U.S. Geological Survey, Water-Resources Investigations Report 86-4347, 66 p.
Aucott, W. R., Davis, M. E., and Speiran, G. K., 1987, Geohydrologic framework of the Coastal Plain aquifers of South Carolina: U.S. Geological Survey, Water-Resources Investigations Report 85-4271, 7 sheets.
Aucott, W. R., and Speiran, G. K., 1985, Ground-water flow in the coastal plain aquifers of South Carolina: Ground Water, v. 23, p. 736-745.
Brown, P. M., Brown, D. L., Reid, M. S., and Lloyd, O. B., Jr., 1979, Evaluation of the geologic and hydrologic factors related to the water-storage potential of Mesozoic aquifers in the southern part of the Atlantic coastal plain, South Carolina and Georgia: U.S. Geological Survey, Professional Paper 1088, 37 p., 11 plates.
Colquhoun, D. J., Woollen, L. D., Van Nienwenhuise, D. S., Padgett, G. G., Oldham, R. W., Boylan, D. C., Bishop, J. W., and Howell, P. D., 1983, Surface and subsurface stratigraphy, structure and aquifers of the South Carolina Coastal Plain: Columbia, SC, State of South Carolina, Office of the Governor, 78 p.
Gohn, G. S., Higgins, B. B., Smith, C. C., and Owens, J. P., 1977, Lithostratigraphy of the deep corehole (Clubhouse Crossroads Corehole 1) near Charleston, South Carolina: U.S. Geological Survey, Professional Paper 1028E, p. 59-70.
Kinney, D. M., ed., 1976, Geothermal gradient map of North America: American Association of Petroleum Geologists and U.S. Geological Survey Publication G74014, 2 maps.
Lee, R. W., 1985, Water-quality maps for selected Upper Cretaceous water-bearing zones in the southeastern coastal plain: U.S. Geological Survey Water Resources Investigations 85-4193.
Maher, J. C., and Applin, E. R., 1971, Geologic framework and petroleum potential of the Atlantic coastal plain and continental shelf: U.S. Geological Survey Professional Paper 659, 98 p., 17 plates.
Manheim, F. T., and Horn, M. K., 1968, Composition of deeper subsurface waters along the Atlantic continental margin: Southeastern Geology, v. 9, p. 215-236.
Miller, J. A., 1990, Ground water atlas of the United States-segment 6, Alabama, Florida, Georgia, and South Carolina: U.S. Geological Survey Hydrologic Investigations Atlas No. HA-730-G, 28 p.
Miller, J. A., Barker, R. A., and Renkin, R. A., 1986, Hydrology of the Southeastern Coastal Plain Aquifer System, in Vecchioli, J., and Johnson, A. I., eds., Regional aquifer systems of the United States: aquifers of the Atlantic and Gulf Coastal Plain: American Water Resources Association Monograph Series No. 9, p. 53-77.
National Imagery and Mapping Agency, 2000, Digital terrain elevation data (DTED Level 0)
Renkin, R. A., Mahon, G. L., and Davis, M. E., 1989, Hydrogeology of clastic Tertiary and Cretaceous regional aquifers and confining units in the southeastern coastal plain aquifer system of the United States: U.S. Geological Survey Hydrologic Investigations Atlas HA-701, 3 sheets.
Richards, H. G., 1974, Structural and stratigraphic framework of the Atlantic coastal plain, in Post-Miocene stratigraphy, central and southern Atlantic coastal plain, in Oaks, R. Q., Jr., and DuBar, J. R., eds., Post-Miocene stratigraphy, central and southern Atlantic coastal plain: Logan UT, Utah State University Press, p. 11-19.
Speiran, G. K., 1986, Relation of aqueous geochemistry to sediment depositional environment, Middendorf Aquifer, South Carolina, in Vecchioli, J., and Johnson, A. I., eds., Regional aquifer systems of the United States aquifers of the Atlantic and Gulf Coastal Plain: American Water Resources Association Monograph Series No. 9, p. 79-96.
Temples, T. J., and Waddell, M. G., 1996, Application of petroleum geophysical well logging and sampling techniques for evaluating aquifer characteristics: Ground Water, v. 34, p. 523-531.
Prepared by Andrew Warne.
