[meteorite-list] Chesapeake Bay Impact Crater Drilling Is Over

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Tue Dec 6 13:36:38 2005
Message-ID: <200512061815.jB6IFMt15427_at_zagami.jpl.nasa.gov>

http://www.timesdispatch.com/servlet/Satellite?pagename=RTD%2FMGArticle%2FRTD_BasicArticle&c=MGArticle&cid=1128768548771&path=!news&s=1045855934842

Impact crater drilling is over
Depth of 5,795 feet reached; now experts will assess the data

BY A.J. HOSTETLER
TIMES-DISPATCH
December 6, 2005

The drilling is over, the probing is under way and there's plenty of
packing to do.

The scientists at a drill site on an Eastern Shore farm took their last
core from an ancient impact crater Sunday morning, at about 5,795 feet.
Drilling into the Chesapeake Bay Impact Crater began in mid-September
and ran nearly continuously for almost three months.

After the core was raised in the wind and rain at about 8 a.m., the
scientists began lowering numerous probes into the bore hole and ran
into some minor trouble, said Greg Gohn, the U.S. Geological Survey
researcher directing the project. The probing should end today and the
site will come down, he said.

There was no ceremony to mark the final core, Gohn said. "We were more
glad to be finished than anything," he said. "We're packing up what we
can now."

The USGS paired with the International Continental Scientific Drilling
Program on the nearly $1.5 million project to dig into the basement of
the 53-mile-wide crater. The crater's epicenter is Cape Charles.

Geologists say a fiery space rock, probably an asteroid, blasted into
coastal Virginia more than 35 million years ago, carving a hole that
quickly filled with tons of water, rubble and debris.

The Chesapeake Bay Impact Crater is the largest of its kind in the
United States and the seventh-largest in the world. It sits 1,000 feet
beneath the lower part of the bay, surrounding peninsulas and the
intercontinental shelf of the Atlantic Ocean.

Earlier bore holes were drilled along the crater's outer rim in Mathews
County, Newport News and at NASA's Langley Research Center. The deepest
was about 2,700 feet.

In early March, dozens of scientists will gather for a "sampling party"
to retrieve specific sections of the cores, housed by the USGS in
Reston, for their research.

Scientists expect the drilling to reveal more about the effects the
prehistoric impact had on the region's geology and water supply and to
help better estimate the space rock's speed, size and energy as it
slammed into the seabed. Other scientists will study samples of
prehistoric water found in the cores that had been trapped in the
crater's depths by the impact's aftermath.
Received on Tue 06 Dec 2005 01:15:20 PM PST