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

I'm back from Bermuda. Nice pictures of unconformities to follow, after developing and scanning...So let's see what kind of trouble TB has gotten himself into while I was lounging on the beach and stuffing myself with gourmet food.

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Originally posted by Tranquility Base:
The entire Precambrian doesn't have ordered paelocurrents - that is more like your epeiric seas....
...You can't argue wioth data....
...The basic point is you would not get paleocurrents from a gradual innundation. You would get the Precambiran type zero paelocurrent strata. That is my well founded expectation...

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...Either way there is something very different about Paleozoic and Precambrian innundations. One was rapid, the other was not.

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...zero currents in the Precambrian marine beds...

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This argument is directly contradicted by your own sources...

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Pettijohn, p520-521
"The stability or persistence of a particular paleocurrent system through time is indeed one of the most astonishing results of paleocurrent measurements. Cross-bedding in a 12,000 foot (3,660m) sequence in the Moine series of Scotland displays a uniformity of orientation throughout which was described by Sir Edward Bailey as "the most surprising single phenomenon" displayed by these strata (Wilson et al Geol Mag 90,377-387 (1953)

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The Moine series of Scotland is preCambrian. Your entire thesis is nullified by your own reference. This illustrates the pitfalls of relying on Creationist secondary sources (those with agendas that conflict with scientific honesty and integrity). Always check the primary literature.You can't argue with the data.

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Originally posted by Tranquility Base:
Wehappy

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Good point about the Moine. I am basing my statement on Chadwick's stuff (see above post to Joe). The Moine example was an example of constant paleocurrent through time. Although we find that interesting we are even more interested in paleocurrents spatially.

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That is a very weak dodge. Your Pettijohn source mentions the spatial relationship... "a uniformity of orientation throughout..." that is consistent with the mainstream sedimentary facies interpretation for the Moine (a Proterozoic marine shelf). As Joe pointed out, pC paleocurrent data is plentiful (considering the scarcity of outcrop). Here's an example showing strong regional and spatial consistency with temporal variation controlled by regional tectonism and basin evolution...
Determination of [i][b]Basinwide[/i][/b] Paleocurrent Patterns in a shale using AMS"The parallel paleocurrent pattern down this paleoslope towards the SSE (fig 4) is what one might expect in such a setting (Pettijohn et al., 1987)""Overall transport to the NNE... is in good agreement with the previously described northward decrease in grain size, sand content, and sandstone/shale ratio.""Paleoflow patterns indicate a change of basinal configuration between the lower and upper members of the Newland Formation.""The coherence of paleocurrent data within a given interval indicate remarkable long term stability of paleocurrent and sediment dispersal systems."Without a shred of data to support YOUR conclusions, this paleocurrent idea of yours appears to be another in a growing list of unsupportable fantasies constructed by an active imagination fueled by religious preconceptions.

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Originally posted by Tranquility Base:
Wehappy, anywhere there are non-zero paleocurrents there is going to be regional consistency so we can agree on basinal 3D topography issues. We all understand that - it couldn't be any other way. I'm talking about continent-wide consistency and that is where Chadwick claims the Paleozoic and Mesozoic differ from the Precambrian and Cenozoic. If there is no mainstream collection of data on this then that is a mainstream lack. Chadwick has done the global story and that is his conclusion. I can't find a mainstream gobal view. Can you?

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Your source - Chadwick - does not agree with your conclusion state above..."the Mesozoic appears not to be under the influence of any prevailing continent wide vectorial forces.""During the Paleozoic, in sharp contrast to Mesozoic, Cenozoic and Precambrian tendencies, clear and persistent continent-wide trends are normative. Sediments moved generally from east and northeast to west and southwest across the North American Continent. "So the Mesozoic and Cenozoic are essentially identical to the preCambrian, according to Chadwick.Chadwicks punchline appears to be this:
Paleozoic paleocurrents indicate the influence of directional forces on a grand scale over an extended period. Various authors have attributed the directionality to such things as "regional slopes," but it is difficult to see how this could apply to deposits of such diverse origins over so wide an area.So it appears that Chadwick's central problem is his inability to incorporate the simple fact that the formation of Pangea dominated the sedimentary history of the Paleozoic. This is a singular event in Phanerozoic time, so of course the sedimentary and paleocurrent data are unique. At no other time in the last 600 million years has a continental landmass existed adjacent to N. America. The collision formed mountains. The mountains eroded for hundreds of millions of years, shedding sediments. It should be no surprise at all that these sediments traveled downhill onto the N. American craton. At all other times, including most of the preCambrian, sediments and currents flowed from the center of the craton outward - leaving no continent-wide vector.This appears to be another case of a Creationist applying the strictest, most outdated forms of gradualism and uniformitarianism to the geologic record, and coming up with a puzzled look on his face - as expected.His finding that the Proterozoic paleocurrents are, overall, directionless on a continental basis is equally unsurprising. Even with a few pre-Pangea supercontinents thrown in, averaging data over a few billion years will zero out almost anything.

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Originally posted by Tranquility Base:
How can you say that our theory doesn't explain cyclothems? For a start I haven't put forward a detailed one and the qualitative one (surges of marine vs fresh water flooding) makes a lot of sense becasue it doesn't need to appeal to bizaree repetitions of uplift/flooding/peat bog/subsidence/innundation and it connects the coal formation with the innundations more causally.

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Why am I almost the only one that gives jargon free summaries of texts around here? Why don't you summarize the mainstream cyclothem theories. You may have seen cyclothem deposists but isn't it possible you've simply accepted the non-catastrophic rationalizations? Why can't you even say that our explanation could be right?

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If the word flood is a naughty word then what word do you use to descibe local floods? Diluvial? Isn't that equally naughty? I think most of the non-marine beds could be reinterpreted as diluvial.

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Doesn't the sub-continental scope of many of these beds trouble you at all? Honestly.

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Pictures are so helpful sometimes... The sandstone filling a dendritic channel, shown in cross-section above, viewed as an isopach below... A bigger map with paleogeography reconstructed from this data. Note the meandering channel flowing out into the birdsfoots delta... All those varying depositional settings plus lots of time and sea-level changes result in a complicated cross section... Read about Pennsylvanian cyclothems here: http://www.dep.state.pa.us/dep/deputate/minres/districts/cmdp/Chap08-1.html"Waxing and waning of continental glaciers resulted in episodic sea level changes, similar in amplitude to those during the Quaternary (~100 m; Heckle, 1995). Klein and Willard (1989) evaluated the relative impacts from these two mechanisms on the Pennsylvanian Period coal basins of the United States. They attribute the control of cyclothems in the Western Interior Basin to repeated transgressions and regressions of a mid-continent sea. These changes in sea level were caused by glaciation. Klein and Willard conclude, based on the more clastic nature of Appalachian sediments and the deeper basin warping, that the Appalachian Basin was affected most by tectonic controls. They also invoke a combination of transgressive-regressive cycles and tectonism as controls on cyclicity in the Illinois basin."Not a global Flood. [i]"Two more factors have been proposed to explain the distribution of coals and intervening sediments. These are the "deltaic" model of Ferm (1970, 1974) and Donaldson (1969, 1974, and 1979) and the "climatic" model of Cecil et al. (1985) and Donaldson et al. (1985). The deltaic model accounts for rapid facies changes that occur over very short horizontal distances. These rapid changes are due to repetitive channel switching, as in the [b]modern Mississippi delta.[/i][/b]"!!!!!!"The climatic model explains the marked vertical stratigraphic, sedimentological, and mineralogic variations from the beginning to end of Pennsylvanian sedimentation, throughout the Appalachian Basin, and explains chemical and physical changes in coals through time. For example the red beds found in the Conemaugh Group are attributed to dry conditions. The widespread freshwater lake deposits of the upper Allegheny and Monongahela Groups are also indicative of dry conditions (Cecil et al., 1985). "Dry conditions = not a global FloodNow go ahead and find a Flood "geologist" who is willing to explain the Flood in terms of actual outcrops, rocks, thin-sections, and data...