Review of Geology of Mississippi Salt Domes Involved in
Nuclear
Research
Charles T. Swann
Mississippi salt domes were a part of nuclear
research activities as early as
1960. Bruinsburg dome, Claiborne County, was initially considered suitable as a
site for underground
nuclear
tests in the Ripple Program. The Bruinsburg dome is
a shallow piercement dome with cap rock 1,629 ft below the surface. Additional
screening resulted in Tatum dome, Lamar County, being chosen as the test site.
Approximately 2,700 ft below the surface, two
nuclear
devices were detonated,
one in 1964 and one in 1966. These detonations are referred to as Project
Dribble and Project Sterling respectively, and are part of the Vela Uniform
Program sponsored by the U.S. Department of Defense and the former U.S. Atomic
Energy Commission. Tatum dome is a shallow piercement dome with cap rock appro
imately 900 ft below the surface.
More recent investigations (1974-1987) were initiated to choose a site for
the nation's first high-level nuclear
waste repository. These investigations,
sponsored by the U.S. Department of Energy, identified the Lampton (Marion
County), Richton (Perry County), and Cypress Creek or Agnes (Perry County) domes
as preferred sites. Lampton dome, a shallow piercement dome with cap rock at
1,305 ft below the surface, was later rejected from the repository siting
process. The Cypress Creek dome is a shallow piercement dome with cap rock at a
depth of approximately 1,195 ft. The Richton dome, Mississippi's shallowest salt
structure, has cap rock as shallow as 497 ft below the surface. Richton and
Cypress Creek domes were considered potentially acceptable sites, although all
present repository iting activities are focused on the Yucca Mountain site, Nye
County, Nevada.
Nuclear
research regarding Mississippi salt domes has yielded abundant
geologic data and short-term economic benefits. However, timing of research and
private utilization plans at Bruinsburg and Richton domes suggest that the
research activities have had a detrimental effect on utilization of Mississippi
salt resources. This potential conflict of salt dome uses may have influenced
private industry to seek other sources of salt supply. Tatum dome, contaminated
by highly radioactive isotopes, can never be utilized for any purpose. These
factors may contribute to the fact that none of Mississippi's 61 known salt
domes are being commercially utilized.
AAPG Search and Discovery Article #91029©1989 AAPG GCAGS and GC Section of SEPM Meeting, October 25-27, 1989, Corpus Christi, Texas.