[meteorite-list] Carolina Bays, etc. meteor

From: Keith <littlejo_at_meteoritecentral.com>
Date: Thu Apr 22 10:08:31 2004
Message-ID: <Pine.SOL.4.33.0209251555420.19941-100000_at_katie.vnet.net>

On Wed, 25 Sep 2002 14:04:50 -0400,
Rothery Melvin ann.melvin_at_sympatico.ca wrote:

>Most of the authorities with which I am familiar
>discount the possibility of an impact along the
>Carolinas and Virginia coast, excepting Chesapeake
>Bay; however, there are those who prefer otherwise
>and one such is Rufus Johnson who has written a small
>speculative pamphlet, The comet of doom, (Roanoke
>Rapids, NC: Kerr Books; 2001), which does not
>convince me.

There are a number of recently published studies that
have looked at the internal structure using cores and
ground-penetrating radar and dated the age of the
Carolina Bays. This is research, which is ongoing, has
found nothing in the way of evidence that supports the
impact hypotheses for their origin and provides a lot
evidence for them being oriented lakes whose current
morphology is the results of 100,000 to 80,000 years
modification by erosion and accretion along the
shorelines of these landforms. If nothing else, the
morphology of these bays have been so altered over
the Pleistocene that their current morphology cannot
be used to argue for an impact origin.

For example, Optically Stimulated Luminescence (OSL)
dating of the sand composing the rims of the Carolina
Bays showed that they formed at various times between
80,000 to 100,000 years ago. For a summary this recent
research go read "Age and Climatic Correlates of
Carolina Bays and Inland Dunes of the South Atlantic
Coastal Plain: New Data" at

http://www.cla.sc.edu/sciaa/srs.html

On that web page it is stated:

"On the U.S. Department of Energy's Savannah River
Site (SRS), adjacent to the Savannah River in the Upper
Coastal Plain, two OSL dates from the rim of Flamingo
Bay indicate that the bay formed initially at
108.7 1 10.9 ka B.P. and was rejuvenated at
40.3 1 4.0 ka B.P. A single date from Bay 40 indicates
that it formed at 77.9 1 7.6 ka B.P."

The Carolina Bays are also older than surficial dunes
that have been dated using OSL dating at "29.9 1 2.8
ka B.P., 31.4 1 2.5 ka B.P., 35.8 1 4.8 ka B.P.,
36.7 1 6.0 ka B.P., and 39.0 1 4.5 ka B.P." This is
discussed in detail at:

http://www.cla.sc.edu/sciaa/srs.html

The idea that the Carolina Bays "must be quite young--
either late Wisconsinan or early Holocene" is soundly
refuted by the above recent research by Brooks and
Taylor (2001).

The above web pages discusses what Brooks and Taylor
have to say about the Carolina Bays.

In addition, Grant et al. (1998), using ground-penetrating
radar to study the internal structure of the rims of some
Carolina Bays, show that they are **not** "essentially
unaltered", but rather the evolution of these bays is
characterized by multiple periods of bay-rim accretion
with intervening intervals erosion. The more recent
research, e.g. Brooks and Taylor (2001) and Grant (1998)
refutes an Early Holocene to Late Wisconsinan age for the
Carolina Bays and greatly disputes an extraterrestrial
origin for them. For on-line details, a person can go to

http://www.cla.sc.edu/sciaa/srs.html

Another URL:

NEBRASKA'S CAROLINA BAYS by ZANNER, C. William
http://gsa.confex.com/gsa/2001AM/finalprogram/abstract_22324.htm

References Cited:

Brooks, M. J., B. E. Taylor, P. A. Stone, and L. B.
Gardner (2001) Pleistocene encroachment of the Wateree
River Sand Sheet into Big Bay on the middle coastal plain
of South Carolina. Southeastern Geology. vol. 40, no. 4.,
pp, 241-257.

Grant, J. A., M. J. Brooks, and B. E. Taylor (1998) New
constraints on the evolution of Carolina bays from ground-
penetrating radar. Geomorphology vol. 22, pp. 325-345.
http://www.uga.edu/srel/Reprint/2276.htm

Another Important Recent Reference:

Brooks, M. J., B. E. Taylor, and J. A. Grant (1996)
Carolina bays and Holocene landscape evolution on the
Upper Coastal Plain of South Carolina. Geoarchaeology.
vol. 11, pp. 481-504

Yours.

Keith
New Orleans, LA
Received on Wed 25 Sep 2002 04:00:40 PM PDT


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