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I don't assign much credibility to Eyton and Parhkurst's work. They propose a late Pleistocene-Early Holocene date for Carolina Bays. If that were the case, bays would occur on the Wando formation in the Carolinas...which was surficially exposed at that time...but they do not. The Wando was deposited ~90,000 years ago, and was exposed certainly during Wisconsinian glaciation, if not well before. Bays are well expressed, however, on the Socastee formation, which was laid down around 200,000 years ago, and exposed by the time the Wando was forming. Bays are commonly found as far inland as the Duplin formation (~2.6 to 3.8 Million ya)(and, by the way, at substantially higher elevations than mentioned by Eyton and Parkhurst). They are very rare on the landward Tar Heel formation (upper Cretaceous), although I have found a couple. I have not identified any on the Middendorf formation (also upper Cretaceous, but older and more landward than the Tar Heel). There aren't many stable Palic landforms on the Middendorf, but there are a few, and one would think that if bolide impact caused the formation of bays, some would be found on the Middendorf. In the absence of shocked quartz, I still maintain that the phenomenon is best explained hydrologically.

I am going to try to compose a coherent response to this reply and your Freepmails into one. I made a promise to myself I wouldn't stay up this late again, but I have spent literally hours trying to piece some things together, and if I don't do it now....

Most indicators tell us the bays themselves are old; maybe very old. One thing that bothers me about them being in excess of say 100,000 years old, is the apparent lack of erosoin of their features. Also, the elevations these things are found in the US and especially other places around the world(which I would like to see you address) all but preclude their being created by sea level fluctuations. BTW, best I could determine, the last time we saw sea levels greater than they are now was ~120,000 years ago. They have more or less steadily risen since then. A relatively crude map but about as good as I could find:

In the absence of shocked quartz...

Do you know if this feature was found at the Tunguska site?

I still maintain that the phenomenon is best explained hydrologically.

While not impossible at elevations of 1500 - 1600 feet(maybe more?) at other sites around the world, there may have been something else at work. Fast melting glaciers? Ice dams giving way? We would maybe find some of these "up north" then? Maybe the great flood was somehow involved???

All's I know is it's way past my bedtime........again!

FGS

Renfield, my copy of the map you suggested purchasing has arrived:

"James P. Owens' "Geologic Map of the Cape Fear Region, 1 degree x 2 degree quadrangle, and Northern Half of the Georgetown 1 degree x 2 degree quadrangle, North Carolina and South Carolina"

It didn't take long to locate a Carolina bay on the "Wando Formation," which you have said do not exist.

Here it is outside Southport, North Carolina:
http://local.live.com/default.aspx?v=2&cp=33.931379~-78.035223&style=h&lvl=15&scene=3396068

Cursory review also suggests that arrangement of bays according to their location on terraces, your "stairstep" analogy in Post #119, is not apparent.

"The largest Bays, generally, are geographically nearest the toe of the landward scarp, and average bay size decreases seaward on the terrace...."

This stands to reason because, if it such an observation were valid, such an arrangement would have been apparent to any of the many students of bays through the years and been part of the literature.

I will continue to study the map -- but the statement regarding no bays on Wando is dead wrong unless my eyes deceive me.