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September 28, 2000 NASA'S LANGLEY FIRST STOP IN BLAST TO LOOK AT IMPACT CRATER'S PAST The Department of the Interior is drilling a hole in NASA's back yard. But officials at NASA's Langley Research Center in Hampton, VA, don't mind. This National Research Laboratory sits on the edge of a huge crater where both agencies are collecting geological data from an ancient extraterrestrial event. Thirty-five million years ago, a two-mile-wide bolide (meteor or comet) hit the tip of Virginia's Eastern Shore. When it struck, the fireball reshaped the land, disrupted the existing water table, and dislodged deeper sediment to higher levels across a 56- mile-wide area. The Department of the Interior's U.S. Geological Survey (USGS) Chesapeake Bay Impact Crater Project is a multi-year, multi-agency study of the sombrero-shaped, underground valley. Langley is located on the outer rim of the York-James Peninsula crater area and is hosting the USGS research activity. The USGS has been taking core samples from a planned 2,700-foot-deep drill site since July. NASA will benefit from the drilling in the form of an atmospheric fingerprint left by the bolide's impact. A senior research scientist at Langley's Atmospheric Sciences Competency, Dr. Joel S. Levine, looks forward to the shared science and agency cooperation. "The USGS drilling project at Langley will permit a detailed investigation of a very significant event in the history of our planet that affected all four components of the Earth system -- the atmosphere, the ocean, the land, and the biosphere," said Levine. "We are working closely with USGS scientists to assess what new information about the Earth's early atmosphere may be obtained from analysis of the cores to be obtained during the drilling." In addition, the USGS Western Earthquake Team is conducting a seismic reflection and refraction survey. This involves small, controlled, non-destructive explosions on Langley property to create underground geological pictures of the rim of the largest crater in North America. The crater was discovered after core samples taken off the coast of New Jersey were compared to ones made in southeastern Virginia. Along with a petroleum company's rock formation study made during an oil search in the Chesapeake Bay, the combined test data indicated a large crater. The USGS formally announced the discovery in 1994. NASA's participation in this research is part of the agency's Earth Science Enterprise, a long-term research program dedicated to understanding how human-induced and natural changes affect our global environment. - end - Web sites for the Chesapeake Bay Impact Crater Project are at: http://woodshole.er.usgs.gov/epubs/bolide/ |