[meteorite-list] Are the Great Dismal Swamp and Lake Drummond Impact Structures?

From: E.P. Grondine <epgrondine_at_meteoritecentral.com>
Date: Sun, 21 Sep 2014 19:31:46 -0700
Message-ID: <1411353106.33285.YahooMailBasic_at_web163306.mail.gq1.yahoo.com>

Hello Everyone -

While there are many swamps along the east coast of North America, according to the note on wikipedia,

"Scientists believe the Great Dismal Swamp was created upon the last major shift of the continental shelf. The origin of Lake Drummond, one of only two natural lakes in Virginia, is not entirely clear."

As I was reading through "The Fabulous History of the Dismal Swamp Company" by Charles Royster for background on the finances of the colonial land theives, I came upon this passage:

(page 423) "In addition to felling stands of white cedar, they found many large trunks of trees lying on top of one another, covered by water and LAYERS of PEAT". (my emphasis) The great fire of 1806 and other fires left many blackened trees but also "brought to view and into use, more good timber than they injured, by burning the soil down to where numerous trees had lain perhaps fpr a century concealed, and their existence unsuspected," citing contemporary reports.

Perhaps both structures form an astrobleme, with Lake Drummond being the crater, and the swamp defining the blast zone.

While there is no way of knowing without a geological survey, one could hypothesize an impact several times larger than Tunguska (the fallen trees), but whether an airbust or ground impact is unclear. As far as dates go, they may have been formed far earlier than 100 years ago, as indicated by the peat.

In any case, as they are near NASA Langley, perhaps someone local will look into them. While their presence is no certainty of a local impact, a very large concentration of impactites may be present in the soil there.

While I know people who earn their living recovering geological specimens from swamps, they prefer certainties, and a meteorite search would likely be too speculative for them. If you have say scuba equipment, and know exactly what the hell you are doing, perhaps it may a very good place to hunt.

One never knows for sure until one looks...

(PS - I'd like to add that given the muck, heat, insects, and the poison ivy, I feel that this kind of search would be a perfectly wonderful project for Mr. Boslough. Too bad there are only poisonous snakes in the swamp, and no alligators.)

good hunting all,
E.P. Grondine
Man and Impact in the Americas
Received on Sun 21 Sep 2014 10:31:46 PM PDT