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News Release
Address
U.S. Department of the Interior 150 National Center
U.S. Geological Survey Reston, VA 20192
Release Contact Phone Fax
September 5, 2000 Marion Fisher (USGS) 703-648-4538 703-648-4588
Chris Rink (NASA) 757-864-6786 757-864-6333
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This summer the U.S. Geological Survey (USGS) has been drilling a deep hole
inside the edge of a 56-mile-wide impact crater created 35 million years ago
when an asteroid or comet slammed into the ocean near the present-day mouth
of the Chesapeake Bay. The USGS has been conducting the drilling project
right in the backyard of the NASA Langley Research Center in Hampton, Va.
As part of the overall research project, USGS scientists also plan to set
off firecracker-like blasts underground to perform a seismic reflection
survey across the crater’s margin. The seismic survey will begin on or about
September 6 and will be conducted from the Langley Research Center through
Hampton and Newport News to a point near the James River. This survey will
produce a “cat scan” image of the distribution of subsurface materials and
structures inside, outside, and across the crater’s margin.
The scientists working on this aspect of the USGS research project will
produce the seismic waves by firing eight-gauge blank shotgun shells in the
ground at a depth of approximately 12 to 18 inches below the surface, or by
detonating one-pound or smaller explosive charges at a depth of
approximately 10-15 feet below the surface. Because of the small amount of
explosives used, it is doubtful that anyone other than the scientists in the
immediate area of the shot hole will hear or feel anything.
During the past 35 years, the USGS has conducted seismic investigations at
many locations across the United States. Rufus Catchings, a USGS
geophysicist who is coordinating the project, said, “the objective of the
proposed work is to produce an image of the crater margin that will help
scientists understand the formation and location of the buried impact
crater.”
Some of the data gathered by the scientists in the overall Chesapeake Bay
Impact Crater Project will be incorporated into the regional ground-water
flow model that was developed by USGS water resources specialists in
Virginia. Results of the project, which is supported and partially funded by
the Hampton Roads Planning District Commission and the Virginia Department
of Environmental Quality, will assist local and state water resources
managers in making better decisions concerning the availability and use of
ground water, an important water supply in southeastern Virginia.
As the nation’s largest water, earth and biological science and civilian
mapping agency, the USGS works in cooperation with more than 2000
organizations across the country to provide reliable, impartial scientific
information to resource managers, planners and other customers. This
information is gathered in every state by USGS scientists to minimize the
loss of life and property from natural disasters, to contribute to the
conservation and the sound economic and physical development of the nation’s
natural resources, and to enhance the quality of life by monitoring water,
biological, energy, and mineral resources.
