[meteorite-list] Scientists Blast Into The Earth's Past in Virginia (Chesapeake Bay Crater)

From: j.divelbiss_at_att.net <j.divelbiss_at_meteoritecentral.com>
Date: Mon Oct 11 15:41:21 2004
Message-ID: <101120041941.18030.416AE1DD00082FDE0000466E21604666489C9C070D040A90070BD206_at_att.net>

The story below says the impact was at 76,000 mph or 111,500 feet per second. That sounds too high to me...by a factor of 3 or 4. Any comments out there?

John

> No one knows whether an asteroid or a comet gouged the one-mile-deep,
> 56-mile-wide crater beneath the Bay. But judging by the damage it caused
> , the meteorite slammed into the planet at about 76,000 mph. The
> explosion, equal to 10 trillion tons of TNT, wiped out life for miles
> around, creating the largest impact crater in the United States and the
> sixth-largest in the world.

-------------- Original message from Ron Baalke : --------------

>
>
> http://home.hamptonroads.com/stories/story.cfm?story=76631&ran=167519
>
> Scientists blast into the Earth's past in Virginia
>
> David Powars, the scientist who worked tirelessly to begin the project
> to study the impact crater, gives an impromptu history lesson about the
> crater to tourists in Cape Charles on the Eastern Shore.
> David Powars, the scientist who worked tirelessly to begin the project
> to study the impact crater, gives an impromptu history lesson about the
> crater to tourists in Cape Charles on the Eastern Shore. PHOTOS BY VICKI
> CRONIS/THE VIRGINIAN-PILOT.
>
> By JOANNE KIMBERLIN
> The Virginian-Pilot
> October 11, 2004
>
> EASTERN SHORE - Crickets thrummed in the dark mist. A harvest moon
> glowed orange in the heavens. The Earth moved.
>
> Thirty-five times.
>
> It shuddered repeatedly because scientists detonated a 20-mile-long
> string of underground explosives along Virginia's Eastern Shore last
> week. The concussions, bouncing back from far below, will help map the
> most detailed profile yet of an ancient wound in the planet's crust: the
> 35-million-year-old Chesapeake Bay impact crater.
>
> Pushing the button was the easy part; reaching countdown required a
> diplomatic endeavor worthy of the United Nations .
>
> Scores of locals had to open their gates to dozens of scholarly visitors
> - a remarkable consensus in a community that doesn't cotton much to
> intrusion .
>
> One by one, residents yielded to the common good , and to the
> long-winded, high-wattage, caffeine-powered zeal of a wiry scientist
> from the Shenandoah Valley, the man who loves the crater the most .
>
> No one knows whether an asteroid or a comet gouged the one-mile-deep,
> 56-mile-wide crater beneath the Bay. But judging by the damage it caused
> , the meteorite slammed into the planet at about 76,000 mph. The
> explosion, equal to 10 trillion tons of TNT, wiped out life for miles
> around, creating the largest impact crater in the United States and the
> sixth-largest in the world.
>
> Thousand-foot-tall tidal waves likely topped parts of the Blue Ridge
> Mountains.
>
> Concealed by the Bay and filled in the passing eons by rock and
> sediment, the crater wasn't discovered until the mid-1980s.
>
> David Powars was one of the first scientists convinced of its existence
> - a notion many of his colleagues had scoffed at for years. Now
> confirmed by a battery of drill samples and other tests, the crater will
> be investigated deeper than ever next fall, when a $1.5 million core
> hole punches 7,000 feet into its mysteries.
>
> Scientists now suspect the crater is the culprit behind a host of
> modern-day concerns, from the region's shortage of fresh ground water to
> its slow sink into the sea. Answers could lie inside layers brought up
> in the drill tube. A sort of seismic ultrasound, created by last week's
> blasts, will determine the bull's-eye for the drill bit.
>
> To get the best picture, an alphabet soup of some two dozen "ologists" -
> experts in rocks, fossils, atmosphere, outer space and more - descended
> on the Shore a couple of weeks ago.
>
> Since then, the team has laid a line of 70-foot-deep shot holes that
> stretches from the center of the crater, located beneath the town of
> Cape Charles, to its northeastern rim, near Nassawadox. Some 700
> seismographs, tuned to record the results, had to be poked into the soil
> every 50 yards along the line. All were on private property - often
> co-owned by a web of relatives.
>
> Powars, as the point man of the operation, began knocking on doors in
> March, spinning his spiel, trying to win access to the land he needed.
>
> "I'd get one person's OK and then find out I also had to get it from
> their cousins or their brothers or their in-laws," Powars said. "I bet I
> wound up talking to 150 people. Some of them were scattered across the
> country. One was in a mental institution. Let's just say that one was
> interesting."
>
> Fortunately for Powars, talking is among the things he does best. When
> he's excited, as he is about the crater, his words gush in a non stop
> stream that's almost legendary.
>
> "We all love David," said Greg Gohn, Powars' boss at the U.S. Geological
> Survey. "But you just have to walk away sometimes."
>
> Powars does not take offense.
>
> "I didn't say a word until I was 10," he said . "But I haven't shut up
> since."
>
> His chatter proved effective with landowners.
>
> Many nodded immediately while others required some courting. Powars put
> in plenty of hours perched on living room sofas, answering questions.
>
> "You can't blame them," he said. "Here was some kook wanting to blow up
> things on their land."
>
> Some refused to open their doors to or answer calls from an outsider. To
> breech their stronghold, Powars enlisted the aid of other locals, who
> contacted their neighbors on his behalf.
>
> "By the time it was done, I was adopted," Powars said. "People were
> feeding me meals. Now, I feel like I know the people better in this
> community than I know the ones in my own."
>
> In the end, only one family resisted his enthusiasm, a rejection that
> will leave a mile-long gap in the seismic profile.
>
> "I worked on them until the very end," Powars said, "but they were
> fighting among themselves and just wouldn't come around. It's a set
> back, but we'll have to live with it."
>
> For the most part, meteor mania blossomed as word spread. Almost 100
> people attended a meeting Powars held last month in Cape Charles.
>
> Tom Saunders, a project manager at the town's new Bay Creek development,
> was impressed.
>
> "You can't get 100 people to come to a meeting in Cape Charles if you're
> giving away money," Saunders said.
>
> Saunders helped pave the way for a shot hole on one of Bay Creek's golf
> courses.
>
> "Astronomy is my hobby," he said, "so anything having to do with a rock
> from space is interesting to me."
>
> Saunders would like to see sleepy Cape Charles benefit from its status
> as the crater's ground zero. There has been talk of building an
>
> interpretive center to draw tourists. "Something like this defines the
> kind of whack this old ball can take and shrug off," Saunders said. "If
> one thing can put Cape Charles on the map of global significance, this
> crater is it."
>
> Mayor Frank Lewis isn't convinced an underwater hole is marketable.
>
> "Seems like it'd be hard to start an industry around something no one
> can see," he said.
>
> Other locals are more interested in basic concerns. Granville Hogg gave
> Powars' crew the go-ahead to store equipment and drill shot holes on his
> family's 200-acre property north of Cape Charles. Groundwater is the
> payoff for Hogg.
>
> The crater ruptured underwater aquifers, limiting the region's fresh
> water supply and leaving farmers, residents and developers accusing each
> other of using too much. Studies hope to make some sense of the
> fractured layers, information that could contribute to better decisions.
>
> "There's a whole lot of finger pointing," Hogg said, "but nobody has any
> scientific data to back up any of it."
>
> As for the scientists themselves, they're delighted to be the first to
> explore the anatomy of a crater so well preserved by the blanket of the
> Bay. Exhausted by weeks spent tromping through farm fields and
> bug-swarmed swamps, scientists were thrilled to finally close in on
> detonation last week.
>
> Powars, functioning on too little sleep and too much coffee and candy,
> was a verbal shockwave. An unexpected surplus of explosives and
> seismographs had prompted a last-minute decision to add a short
> east-west cross line of extra shot holes.
>
> Granville Hogg gave scientists permission to blast on his property in
> the hopes that it will reveal why the area's groundwater is limited.
>
> Dashing up and down the line in his pick up, Powars veered off to soothe
> a jittery landowner here, an overworked team member there.
>
> "This is just so exciting," he jabbered, with no apparent need for a
> breath. "We've waited so long. I can't wait to see what this thing looks
> like. Everyone thought an impact this big would wipe out the planet.
> Now, we know they were wrong. We're all so tired. No one knows what's
> under there, you know. A crater like this is just so expensive to drill.
> We know so little about them. Could be some oil down there, but I think
> it's too young for that. Could be gold, platinum, diamonds. A crater in
> Canada is pumping out nickel right now, you know."
>
> By that night, even Powars was silenced by the explosions. Synchronized
> by satellite-set timers, the blasts went off between 10:30 p.m and
> sunrise to minimize vibrations from traffic that might be picked up by
> the sensitive seismographs. Gravel and sandbags capped the shot holes,
> directing the explosions downward to reveal the topography up to nine
> miles beneath the surface. As they went off, a wave of mini-earthquakes
> rocked the Shore.
>
> Under foot, they rippled by with a rubbery jolt.
>
> Inside homes, they rocked beds and rattled dishes.
>
> Despite efforts to get the word out beforehand, many residents were
> alarmed.
>
> "Our dispatcher said she must have had 200 phone calls from folks
> wanting to know what was going on," said Capt. David Doughty of the
> county sheriff's department.
>
> "I thought a car ran into my house," said Berkley Rayfield, a pharmacist
> in Cape Charles. Others wondered if a plane had crashed, if the military
> was up to something, if another meteor had hit, if Iraq had invaded.
>
> "Me and my husband were up all night," said Cela Burge, Cape Charles'
> town manager. "It really freaked us out."
>
> A series of shallower, less-powerful explosions, set off during the day
> , was expected to wrap up Sunday. From there, the recordings will be
> entered into a computer and analyzed. Powars hopes to have a sketch of
> his crater by December.
>
> His hunch says the data will pinpoint Eyre Hall as the best spot for
> next year's deep-hole project. The colonial-era plantation, located just
> south of Eastville, belongs to Furlong Baldwin. Shot holes already dot
> the property. The deep hole could bring an international circus of
> science types to a place Baldwin treasures for its peace.
>
> "I've already told David that we'll cross that bridge when we come to
> it," Baldwin said. "If I can just get him to stop talking, I'll probably
> agree to anything."
>
>
> ______________________________________________
> Meteorite-list mailing list
> Meteorite-list_at_meteoritecentral.com
> http://six.pairlist.net/mailman/listinfo/meteorite-list
Received on Mon 11 Oct 2004 03:41:17 PM PDT