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Author Topic:   Paleocurrents: the 'diverse' features of the GC were laid via rapid, correlated flow
edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 31 of 109 (11581)
06-14-2002 11:08 AM
Reply to: Message 29 by Tranquility Base
06-14-2002 2:05 AM


quote:
Originally posted by Tranquility Base:
Edge, I would love to show you somehting comparing the rapidity of currents to modern ones - I just can't find it in the mainstream literature. I don't think Pettijohn commented on it in his book either - I was looking out for it.
Ah, there's a reason for that, you know.
quote:
The surprise expressed by the researchers quoted by Pettijohn is what makes me think the rapidiy and order are 'not normal'.
Not at all. At least that's not the way I was taught. Besides, you just said that you cannot find anything on higher velocities, so why do you presume Pettijohn to have thought the currents were unusual? The surprise they expressed was that the currents would so accurately reflect the paleoslope. They simply thought that there would be more noise.
quote:
My statement about the Precambrian is admittedly sourced from Chadwick's creationist summary (see the first post).
I'm sure we can find some Precambrian conglomerates for you. Maybe Joe could send us a reference when he has time.
quote:
These researchers are clearly claiming that the paleocurrent meaurements that they summarize as a vector on a map will be characteristic of the local region - not a single data point. It would be meaningless if you go 100 metres away and you get a different result. that is certainly not what they are claiming.
Not sure what you are saying here. Of course the representations should be regional.
quote:
You say what you like but I intuitvely know that currents which can order pebbles and ripple marks are significant.
So are you saying that this does not happen even today? Sorry, TB, but we have plenty of fluviatile currents that can create oriented pebbles and ripple marks. There is nothing unusual here.
quote:
I've searched the USGS-georef and can't find anything relating paleocurrents to modern day currents. There should be a review on the issue somewhere shouldn't there? I only have access to the USGS abstracts.
Usually these are covered in college level geology courses that you have missed. I don't know of any current research in this area since it is pretty well known. Only creationists seem to be behind the curve on the subject and are trying to disprove uniformitarianism.

This message is a reply to:
 Message 29 by Tranquility Base, posted 06-14-2002 2:05 AM Tranquility Base has replied

Replies to this message:
 Message 36 by Tranquility Base, posted 06-17-2002 9:23 PM edge has replied

  
edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 32 of 109 (11583)
06-14-2002 11:16 AM
Reply to: Message 28 by Tranquility Base
06-14-2002 1:42 AM


quote:
Originally posted by Tranquility Base:
Moose, the flow was rapid enough to generate ordered paleocurrent observables. I would expect that in rivers and floods but not systematically on sea floors.
TB, could you show us this paleocurrent data for the Mancos shale or the Pierre Shale? I'd like to see the current velocity estimates for thes formations.
quote:
OK - we're talking non-marine so I'll agree that it is 'normal' for rivers and floods. But in that case you then have to agree that the large non-marine beds were laid by floods (obviously many of them)? If you agree then we're back to the unconformity issue.
Not at all. Your lack of geological training is showing up here. Non-marine formations can be quite extensive. But then we have been over this ground before. Did you just ignore us?

This message is a reply to:
 Message 28 by Tranquility Base, posted 06-14-2002 1:42 AM Tranquility Base has replied

Replies to this message:
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Joe Meert
Member (Idle past 5680 days)
Posts: 913
From: Gainesville
Joined: 03-02-2002


Message 33 of 109 (11584)
06-14-2002 11:25 AM
Reply to: Message 24 by Tranquility Base
06-13-2002 11:51 PM


quote:
Originally posted by Tranquility Base:
You might be right about the diving but I doubt it is enough to explain the data Gene90. 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?
JM: ROTFL! Where did you get this gem? I just finished a proposal on the Vindhyan sequence in India which has wonderful paleocurrent data.
Cheers
Joe Meert

This message is a reply to:
 Message 24 by Tranquility Base, posted 06-13-2002 11:51 PM Tranquility Base has replied

Replies to this message:
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wehappyfew
Inactive Member


Message 34 of 109 (11671)
06-16-2002 10:12 PM
Reply to: Message 6 by Tranquility Base
06-13-2002 1:45 AM


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.
quote:
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...
...Either way there is something very different about Paleozoic and Precambrian innundations. One was rapid, the other was not.
...zero currents in the Precambrian marine beds...

This argument is directly contradicted by your own sources...
quote:
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)
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.

This message is a reply to:
 Message 6 by Tranquility Base, posted 06-13-2002 1:45 AM Tranquility Base has replied

Replies to this message:
 Message 35 by Minnemooseus, posted 06-16-2002 11:40 PM wehappyfew has not replied
 Message 39 by Tranquility Base, posted 06-17-2002 9:36 PM wehappyfew has replied

  
Minnemooseus
Member
Posts: 3941
From: Duluth, Minnesota, U.S. (West end of Lake Superior)
Joined: 11-11-2001
Member Rating: 10.0


Message 35 of 109 (11682)
06-16-2002 11:40 PM
Reply to: Message 34 by wehappyfew
06-16-2002 10:12 PM


quote:
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.
Actually, TB and I have been directly consulting the Pettijohn book (added by edit 6/17/02: Of course, the book isn't "the primary literature", but it is a reliable source). And I did notice that the Moine was pC, although I don't know if TB did (I think that info may have been elsewhere in the book, or perhaps I found it on the web).
The discussion has, more or less, been on marine paleocurrents. I, though, have been trying, to some degree, point out the non-marine-ness of a least some of the geological units TB is citing. I don't have specific information at hand, but I suspect the Moine is also non-marine.
Still a rather amusing self contridiction on TB's part.
I've concluded, and I think TB agrees, that it is impossible to have further meaningful discussion on these paleocurrents, without more specific information on their nature, including the nature of the containing rock units.
TB's source of inspiration was cited earlier in the string. He is a geologist/biologist who teaches at an Adventist university. He has apparently compiled a massive amount of paleocurrent data. The purpose of such is apparently to show widespread consistant paleocurrents in continental marine rocks, as support for "the flood". To what degree his compilation of paleocurrent info is only that of marine deposited rocks, I don't know. It would seem to be further amusement, if many of these paleocurrents were actually found to be from measurements in non-marine rocks.
Moose
------------------
BS degree, geology, '83
Professor, geology, Whatsamatta U
Old Earth evolution - Yes
Godly creation - Maybe
[This message has been edited by minnemooseus, 06-18-2002]

This message is a reply to:
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Replies to this message:
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Tranquility Base
Inactive Member


Message 36 of 109 (11715)
06-17-2002 9:23 PM
Reply to: Message 31 by edge
06-14-2002 11:08 AM


Edge
The 'surprise' recorded by paleocurrent researchers clearly was related to the extent of correlation in time and space. Noise may have been a part of it but not the whole story.
My statement about the meaningfulness of paleocurrent data is that they are typically represetative of a region which earlier you seemed to be be doubting.
Of course rivers and streams generate paelocurrents but not ordered over tens of thousands of square miles!!
I personally felt that Pettijohn was lacking in a section linking real currents today and paleocurrents. I looked for it and unless my memory fails me it is not there. If I were writing a chapter on paleocurrents I would have a section on that and the only reason I would leave it out would be because the research hasn't been done! I hint that that is the case but I somehow doubt that this is still true in the 2000s. If it is I might write up a research grant on it and switch to geology next year.
[This message has been edited by Tranquility Base, 06-17-2002]

This message is a reply to:
 Message 31 by edge, posted 06-14-2002 11:08 AM edge has replied

Replies to this message:
 Message 46 by edge, posted 06-19-2002 12:41 AM Tranquility Base has replied

  
Tranquility Base
Inactive Member


Message 37 of 109 (11716)
06-17-2002 9:25 PM
Reply to: Message 32 by edge
06-14-2002 11:16 AM


Edge
Can you tell nme about the Mancos shale or the Pierre Shale?
I'm aware that the non-marine beds can be extensive. If they are then they're not rivers! You don't need to be trained in geology to know that! Maybe deltaic but not rivers.

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Tranquility Base
Inactive Member


Message 38 of 109 (11717)
06-17-2002 9:31 PM
Reply to: Message 33 by Joe Meert
06-14-2002 11:25 AM


Joe
OK, when I say 'zero paleocurrents in the Precambiran' I should say low spatial order. I admit I have based that on Chadwick's claim and am willing to recant!
Chadwick's (and my) point is that the paleocurrents in the Precambrian are locally dictated (presumably by local 3D topography) and not non-locally dictated like those of the Paleozoic. I'm willing to be reeducated on the extent of non-localness of the Precambrian but that is not the same as simply showing that the Precambian has non-zero paelocurent observables as I have pointed out.

This message is a reply to:
 Message 33 by Joe Meert, posted 06-14-2002 11:25 AM Joe Meert has not replied

  
Tranquility Base
Inactive Member


Message 39 of 109 (11718)
06-17-2002 9:36 PM
Reply to: Message 34 by wehappyfew
06-16-2002 10:12 PM


Wehappy
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. As I pointed out above I have no problem with local non0-zero paelocurrents in the Precambrian. The issue is spatial correlation.
The straights of Gibraltar might be expected to display high velocity non-zero paelocurrents but not necessarily the rest of the Mediterranian.

This message is a reply to:
 Message 34 by wehappyfew, posted 06-16-2002 10:12 PM wehappyfew has replied

Replies to this message:
 Message 41 by wehappyfew, posted 06-17-2002 11:49 PM Tranquility Base has replied

  
Tranquility Base
Inactive Member


Message 40 of 109 (11719)
06-17-2002 9:42 PM
Reply to: Message 35 by Minnemooseus
06-16-2002 11:40 PM


Moose
I agree with much of your post and see above.
By the way, I was introduced to paleocurrents by Pettijohn this January and formed my own impression of their significance.
I strongly suspect that most of the paleocurrent data is from marine rocks because most rocks are marine! But I could be wrong.
Q: Why do you still think that non-mariness would be a problem for us? Spatially ordered non-marine high velocity beds are diagnostic of the/many floods aren't they?

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 Message 35 by Minnemooseus, posted 06-16-2002 11:40 PM Minnemooseus has not replied

  
wehappyfew
Inactive Member


Message 41 of 109 (11729)
06-17-2002 11:49 PM
Reply to: Message 39 by Tranquility Base
06-17-2002 9:36 PM


quote:
Originally posted by Tranquility Base:
Wehappy
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.

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.

This message is a reply to:
 Message 39 by Tranquility Base, posted 06-17-2002 9:36 PM Tranquility Base has replied

Replies to this message:
 Message 42 by Tranquility Base, posted 06-18-2002 12:06 AM wehappyfew has replied

  
Tranquility Base
Inactive Member


Message 42 of 109 (11735)
06-18-2002 12:06 AM
Reply to: Message 41 by wehappyfew
06-17-2002 11:49 PM


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?

This message is a reply to:
 Message 41 by wehappyfew, posted 06-17-2002 11:49 PM wehappyfew has replied

Replies to this message:
 Message 43 by wehappyfew, posted 06-18-2002 1:00 AM Tranquility Base has replied

  
wehappyfew
Inactive Member


Message 43 of 109 (11740)
06-18-2002 1:00 AM
Reply to: Message 42 by Tranquility Base
06-18-2002 12:06 AM


quote:
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?
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.

This message is a reply to:
 Message 42 by Tranquility Base, posted 06-18-2002 12:06 AM Tranquility Base has replied

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Tranquility Base
Inactive Member


Message 44 of 109 (11741)
06-18-2002 1:15 AM
Reply to: Message 43 by wehappyfew
06-18-2002 1:00 AM


Wehappy
Chadwick also says: "In the Mesozoic the currents exhibit increasing variability and shift from predominantly westerly to predominantly easterly." so I presumed there was still some continental tendancies. But in totality Chadwick is saying that is is primarily a Paleozoic phenomenon so I'll stick to the Paleozoic as being continent wide.
The point is that the currents were sufficient to leave ordered paleocurrent observables. I still am almost 100% sure that shallow modern day epeiric seas would not display correlated paleocurrent obsevables! No-one here from either camp has been able to come up with anything relevant to this point other than intuition.
And of course if these observations also extend to non-marine beds that is even more interesting for us.

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Replies to this message:
 Message 45 by edge, posted 06-19-2002 12:38 AM Tranquility Base has not replied

  
edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 45 of 109 (11792)
06-19-2002 12:38 AM
Reply to: Message 44 by Tranquility Base
06-18-2002 1:15 AM


[QUOTE]Originally posted by Tranquility Base:
The point is that the currents were sufficient to leave ordered paleocurrent observables. I still am almost 100% sure that shallow modern day epeiric seas would not display correlated paleocurrent obsevables! No-one here from either camp has been able to come up with anything relevant to this point other than intuition.
And of course if these observations also extend to non-marine beds that is even more interesting for us.[/B][/QUOTE]
Good, then give us some data. You have refused to do so and it is getting rather tedious.

This message is a reply to:
 Message 44 by Tranquility Base, posted 06-18-2002 1:15 AM Tranquility Base has not replied

  
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