Where did the flood waters come from and where did they go?

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They dropped, dramatically (about 50 m), in connection with the ice age, but it is hard to tell whether this was cause, effect, or both.

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from:Palaeos: Page not foundI think you are jumping to conclusions without enough information.For one thing what is "most of North America"? There was a large shallow inland sea up the middle of NA during, IIRC, the cretaceous too. I would not call that transgression "most" but it was a lot of NA.Also, at this time, there were a lot of other areas that were not mostly underwater so how much extra water is required (beyond 150 m)?If if we removed the tectonic uplift from current NA and raised sea levels 150m how much transgression would there be?After you have these details then we can see if the water problem is equivalent for the two models. Not until then can you make any statements.ABE
from: OrdovicianIt appears, eyeballing only, that perhaps 2/3 of NA was wet. Since the current NA (as shown on this map) did NOT EXIST (part of it was added from Europe later. It is hard to calculate "most" under these circustances.It is my understanding that the basic creton of NA is about the part shown on the above referenced map. Where do we draw the boundaries of NA when it was in bits and pieces at the time.I do know that the north pacific coast (to 100's of kms inland from the current coast) was added 100's of millions of years after the Oldevician. The picture shows it as underwater and part of NA but that is incorrect.This message has been edited by NosyNed, 06-21-2005 09:09 PM

So the the support that you think you are using for your position is now: "no one is sure how much was covered"? It was your idea to bring it up. What do you want to do with it now?I read this as an inablility to do more than wave your arms and hope no one notices that this does not correspond to a world covering flood but more like rearrangements (as noted above) of the mostly covered world we have now.see: Population Distribution and Change | SEDACeyeballing this suggests that something like 30 to 50% of South America is under 200 m and about 20% is under 50 m. Since a total ice cap melt would raise sea levels by about 60 m we would get something from 20 to 30 % of SA inundated. That is the current continent that has been uplifted by tectonics.There is no mystery for geology about where the water came from or went. It is your problem.
ABELooking at the supplied numbers give 10 % of the current SA at under 50 m. The eyeballing is probably an overestimate.This message has been edited by NosyNed, 06-22-2005 12:12 AM

Ordovician Paleography of NAThis gives a better picture of the situation and, indeed, the majority (even "most) is covered.Now we have to look at the rest of the world. There are two ways to cover NA with water: raise the sea level (about 70 m with no ice) and get rid of the mountains and uplifted areas.ABE
It seems there is another explanation for the transgressions.See: http://hoopermuseum.earthsci.carleton.ca/...tor/project2.htm

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Continental rifting and the growth of new oceans resulted in greatly extended midocean ridges. As the ridges grew and reduced the volume of the ocean basins, there was a eustatic rise in sea level, resulting in widespread marine transgressions in the Cretaceous.

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The transgressions in North America occured at least twice.This message has been edited by NosyNed, 06-22-2005 12:33 AM

over all global sea level is, btw, eusatic sea level (I learned a new word ).how is this chart determined? 100's of meters measured from where?