Home Archived April 13, 2016

U.S. Geological Survey

Maps, Imagery, and Publications Hazards Newsroom Education Jobs Partnerships Library About USGS Social Media

USGS Newsroom

USGS Newsroom  

Evidence Presented in Toronto... Meteorite Impact Formed Chesapeake Bay Impact Crater Controls Region’s Groundwater Flow and Quality
Released: 10/24/1998

Contact Information:
U.S. Department of the Interior, U.S. Geological Survey
Office of Communication
119 National Center
Reston, VA 20192
Diane Noserale 1-click interview
Phone: 703-648-4333, In Toronto: 416-585-3706 | FAX: 703-648-6859

A large meteorite plummeted into the western Atlantic Ocean about 35 million years ago, creating the 120-km wide Chesapeake Bay impact crater [Geology (Boulder), 22 (8), p. 691-694]. This event and its aftermath, which continues to this day, will be presented by U.S. Geological Survey geologist Dr. David S. Powars at the Annual Meeting of the Geological Society of America scheduled for Oct. 25-29 in Toronto, Canada.

"The impact penetrated the entire coastal plain sedimentary sequence and at least 2 km of basement rock," says Powars. "Subsequently, the crater was filled with the deposits of rock fragments and seawater, and then buried beneath recent marine sediments. The resulting crater has an inner and outer rim, a relatively flat-floored annular trough, and an inner basin with a central uplift and surrounding concentric ridges and valleys. These structural and stratigraphic features control regional ground-water flow, and the outer rim serves as a boundary separating the inner higher salinity water from the freshwater to the west," Powars explained.

"Stratigraphic, Structural, and Hydrogeological Complexities Related to the Outer Rim of the Chesapeake Bay Impact Crater" (poster) is scheduled for 1:30 -5:30 pm Wednesday, Oct 28 Metro Toronto Convention Center Hall-E.

The USGS serves the nation by providing reliable scientific information to describe and understand the Earth; minimize loss of life and property from natural disasters; manage water, biological, energy, and mineral resources; and enhance and protect our quality of life.

Subscribe to receive the latest USGS news releases.

**** www.usgs.gov ****

Links and contacts within this release are valid at the time of publication.


Accessibility FOIA Privacy Policies and Notices

USA.gov logo U.S. Department of the Interior | U.S. Geological Survey
URL: http://www.usgs.gov/newsroom/article.asp?ID=1036
Page Contact Information: Ask USGS
Page Last Modified: 10/12/2005 8:57:53 AM