Paleocurrents: the 'diverse' features of the GC were laid via rapid, correlated flow

[QUOTE][b]--Are you expecting flood waters to lay perfectly still while they inundate the worlds continent(s)?[/QUOTE][/b]No, which is why I wouldn't expect to find any of these: http://geology.about.com/library/bl/images/blhoodoo.htmIt would topple too easily.

[QUOTE][b]Gene90, so how did these hoodoos form from a mainstream POV?[/QUOTE][/b]Hard rock capping a limestone (or similar) base. Add eons of rain.Of course, lateral motion from a flood would topple it.

[QUOTE][b]Your continent was flooded by rapid correlated marine flows and this was supplemented by freshwater flows down slopes.[/QUOTE][/b]Then you need intact deltas high upon mountain ridges.

[QUOTE][b]Edge, we'll have to see what the modern strata paleocurrents look like but I already know that you will not get ordered paleocurrents across thousands of square miles of today's shelves (I have scuba dived).[/QUOTE][/b]I have some limited experience here as well. The places we dive are shallow (most of the time under 100') and are almost always near obstructions (wrecks, reefs, ledges, etc) that will disrupt the natural direction of the current--that's why there is so much marine life there. Also we usually dive not only on the continental shelf but very near land, where inconsistencies in the shape of the beach will redirect currents and where tidal currents become an issue. If we were 100 miles offshore over a uniform bottom the direction of the current would likely stay fairly consistent. (But it probably wouldn't be worth the dive)In short, SCUBA people dive the anomalies and pass over the 'normal' sea bottom. I feel that what we see down there is likely *not* representative of the 'typical' bottom.

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Originally posted by Tranquility Base:
Remember the entire Precambiran systematically has near zero paleocurrents. I really think that is what you will see for the normal situation. If you think currents sufficient to generate continent wide paleocurrents are the norm then why zero currents in the Precambrian marine beds?

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Precambrian sedimentary deposits are poorly represented, hence few paleocurrents from the Precambrian. But it looks to me like they are relatively well represented. Perhaps you can better explain your position, I'm (obviously) a bit confused. http://geology.swau.edu/paleocur/precatot.htmlAs for the Hoodoos, they are caused by a water resistant rock (such as basalt) covering less resistant or more porous rock (limestone or sandstone). Rainwater will have access to the entire structure except rock directly under the basalt (or whatever) cap. The result is the rest of the formation eroding away except the basalt boulder and the sandstone underneath, now holding it high in the air.You can see something rather similar happen in miniature when pebbles rest upon clay or silt that is exposed to rain, since most of the erosion is from the impact of raindrops, the rest of the clay bed washes away, leaving the pebbles elevated a few centimeters above the ground, now supported by pillars of clay directly underneath.Ah the joy of a childhood spent walking into stuff.

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TrueCreation Are we aware of any "paleohoodoo's"?

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I'm not the one to ask. *But* I think there *could* be such a thing. The place to look would be 'fossil' dunes or perhaps other aeolian deposits. It sounds like a terribly esoteric thing to look for but might give clues regarding paleoseismology.

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[This message has been edited by gene90, 06-13-2002]