Re: U of South Carolina Releases Topper Radiocarbon Dates

From: Lee Olsen (paleocity_at_hotmail.com)
Date: 11/30/04 

Date: 30 Nov 2004 07:39:37 -0800

icycalmca@yahoo.com (Daryl Krupa) wrote in message news:<c70365ef.0411262320.52358a2c@posting.google.com>...
> paleocity@hotmail.com (Lee Olsen) wrote in message news:<40a73547.0411241031.52c0085a@posting.google.com>...
> <snip>
> > The excavations have uncovered an enormous amount of ground and not
> > just a tiny fireplace pit. Where's the beef (oops, I mean humus) and
> > better yet, why should there be any in the first place 50 thousand
> > years ago? Humus soil does not necessarily form in dunes, but it
> > doesn't seem possible that some wouldn't have formed somewhere in that
> > amount of time. I have never been to the Topper area, but I can assure
> > you out here on the Pacific Coast vegetation takes hold in the dunes
> > and on the over-bank flood-plains rather rapidly. For example, the
> > Kennewick Man site has 14C dates on humus (this area gets only 7
> > inches of rain a year and no oak, pine etc. grows there) and the
> > Columbia River has a history of more violent flooding than anything
> > seen on the Savannah River. The *no humus* seems like a legitimate
> > puzzle.
> <snip>
>
> I forgot to mention the most obvious (and most problematic) explanation
> for the lack of humic paleosols at depth: consumption by fire.

I don't think you will have much luck selling this idea.

http://www.nps.gov/yell/nature/fire/
"Surveys revealed that less than 1% of soils were heated enough to
burn below-ground plant seeds and roots."

http://www.x98ruhf.net/yellowstone/fire.htm
"Many people thought that Yellowstone would never recover. Scientists,
however, knew that fire was a necessary part of the cycle of life in a
forest. Life would not only go on, but would also benefit from the
fire."

>
> Open boreal woodland near Late Glacial Maximum:
>
> "This vegetation map showing the eastern USA during the period
> 28,000-25,000 14C y.a. has been compiled by Paul & Hazel Delcourt.
> An ice *** already covered most of Canada and extended south of
> the Great Lakes. Boreal conifer woodlands and forests predominated
> in what is now the cool temperate forest zone, and the cool and
> warm temperate forest belts were compressed southwards."

The URL I cited in my reply to Bob cited Delcourt and Delcourt.
And, since none of these URLs gave an opinion for the time in
question, c50 k 14C date, I compared that with the GRIP cores and see
no climate match for a forest of the hearth type. Maybe the GRIP dates
are off?

>
> http://www.esd.ornl.gov/projects/qen/NAm28-25kyr.gif
>
> "28,000-25,000 14C y.a.; shortly before Last Glacial Maximum.
> In the eastern USA, conditions may have been generally drier than today.
> A xeric scrub cover existed in Florida at this time, instead of the
> present forest (Watts & Stuiver 1980).
> In Maryland (38N, 75W) pollen evidence indicates pine-birch barrens or
> spruce parkland
> dominating after 30,000 14C years ago (Wells 1992 p.612), and it is
> possible that most of the eastern USA had an open wooded vegetation
> cover at this time."
>
> http://www.esd.ornl.gov/projects/qen/nercNORTHAMERICA.html
>
> Hmmm ... xeric scrubland ... fire-dominated ecosystem ... IIRC,
> Georgia pines are well-adapted to both sandy soils and a regular
> occurrence of fire.
> Dry piney duff burns ferociously, and fires in such environments
> often totally consume what surface organics might have acculmulated.

I'm not going to buy this idea. I just drove through the remnants of a
pine forest fire last Thursday. You can't burn a forest down. By the
time the dead trees and roots rot, new trees are growing better than
ever.

Then:
http://www.tillamoo.com/burn.html

Today you can drive through this area and you would never know there
was even a fire there unless someone told you:
http://www.tillamookforest.org/

Unusual conditions may impede regrowth for a short time, but on the
hundred-year-scale fires have no detrimental impact at all.

 
> What ash remained could have been stripped by winds, to be
> redeposited in lower ground (or carried away by the river when it
> topped the bank [no pun intended]).
> The lack of humic horizons in the sediment face might indicate that
> they tended to be catastrophically oxidised before being covered with
> a preserving layer of sediment.

Doesn't happen that way. If all the seeds and roots blew away (and
they can't blow away forever) there wouldn't have been a pine forest
in the first place.

Anyway, it's the oak and buckeye that troubles me. See fig 24.2.

> Fragments of pine cones would be interesting to investigate.
>
> A shallow fire pit might be a localised site of aeolian redeposition
> of burned remnants of forest or forest floor material, followed by
> aeolian deposition of mineral material to flatten out the surface,
> but then,
> so would a hollow created by a wallowing bison.

First it has to be proven that an oak, pine, cherry and buckeye system
was in place at the time of Stafford's 14C dates.
 
> There's a site in northwestern Alberta (Saskatoon Mountain) that is
> similar in many ways: a hillside above a source of aeolian sediment
> (dried-out drained-glacial-lake bed), where the prevailing westerlies
> tended to deposit layers of silty sand just below the crest of the hill,
> where the wind velocity decreased after compression of the transporting
> air mass by the hillside below.
> Some humic horizons there, along with some evidence of fire.
> The oldest artifacts, 9500 BP, predate the establishment of
> coniferous boreal in the area, and thereafter vegetation cover
> tended to anchor the lake surface and limit sediment removal to
> the dig site, and so the record ends quite early.
> Conditions at the Topper site might possibly have been similarly
> susceptible to climatic and vegetation-cover influences, creating
> interruptions or hiatuses in the sedimentary record.

Sure, nothing is constant, but 36,000 years of what appears to be a
blank spot except one fire pit and a few iffy tools? Now wasn't that a
lucky shot? Goodyear is quite proud that he dug a little deeper than
the Clovis horizon. But he admits himself: "But river-cobble chert and
the large hammerstones present in the river bottom today are absent
from the pre-Clovis zone at Topper." Another words the fact that he
dug deeper at a Clovis site had nothing what-so-ever to do with the
fact that he hit fire residue. There really isn't any particular
reason for anyone to be at a chert quarry when there isn't any chert.
There are 3 million square miles of land area in the U.S. How many
millions of miles of river shoreline? He just sunk a hole in the
ground and hit by random chance a man-made hearth 50 thousand years
old?

>
> The view upwind:
>
> http://www.pinetreeline.org/photos/belodg/belod228.jpg
>
> The dig, with some evidence of paleosols:
>
> http://www.pinetreeline.org/photos/belodg/belod226.jpg
>
> Reading:
>
> Beaudoin, A. B., M. Wright and B. Ronaghan, 1996.
> Late Quaternary Landscape History and Archaeology in the
> "Ice-Free Corridor": Some Recent Results from Alberta.
> Quaternary International, 32:113-126
>
> Zo, if the dominant vegetation at the Topper site during the
> mid-Wisconsinan interstadial was subject to frequent intensive
> fire distubance, then the lack of humic horizons might be
> explained by conditions tending to act against the chance of
> preservation of surface organic material.
>
> 'Nuff said?

No :-).

>
> Daryl Krupa

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