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Author Topic:   So how did the GC get laid down from a mainstream POV? Deterministic models?
Joe Meert
Member (Idle past 5680 days)
Posts: 913
From: Gainesville
Joined: 03-02-2002


Message 31 of 64 (10265)
05-23-2002 12:47 AM
Reply to: Message 26 by Tranquility Base
05-23-2002 12:12 AM


quote:
How much longer are people here going to deny that there is no good deterministic mainstream model for the origin of the geolgoical column and that even the qualitative mechanisms are only proposals. If you disagree with me - tell us and show us! Isn't this what this BBS is all about
one might just as easily say:
How much longer are people here going to deny that there is no good deterministic mainstream model for ye-creationism and that even the qualitative mechanisms are only proposals. If you disagree with me - tell us and show us! Isn't this what this BBS is all about?
However, in the interest of moving forward maybe you could tell me what you would accept as a deterministic model? You realize that geology is based upon observation and testable inferences from those observations. We observe sedimentation (in its many forms) today (had you carefully read your books you would have noticed people like Hutton and Joly--among others) studying deposition and erosion. If by deterministic you mean 'absolute answer' then the answer is NO, geology cannot do that and, in fact, no science can do this. What we can do is limit the possibilities by amassing the evidence. Geologists of the 17th and 18th centuries wanted to find evidence to support the flood. They also wanted to be honest about what the evidence showed. They approached the Bible as a book of salvation that may have also documented a global flood. What they found was so diamtetrically opposed to a flood that they realized it must be a myth. History strongly suggests that the Hebrew myth was borrowed from the SUmerian epic of Gilgamesh. I am getting a bit off track, but I am beginning to suspect that you are looking in these books for something that no science can do. Only religion can give you absolute answers (and even then, they depend on the religion!). So, please explain what you would accept as 'deterministic' and then explain why creationism is deterministic. Thanks
Cheers
Joe Meert

This message is a reply to:
 Message 26 by Tranquility Base, posted 05-23-2002 12:12 AM Tranquility Base has replied

Replies to this message:
 Message 33 by Tranquility Base, posted 05-23-2002 1:23 AM Joe Meert 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 32 of 64 (10266)
05-23-2002 12:48 AM


I'm already breaking my word, that I wasn't going to post to this topic. Anyhow, just a link to information; little additional commentary right now.
This is the best online description, of the Grand Canyon stratigraphy, that I was able to find:
http://www.kaibab.org/geology/gc_layer.htm#kl
There is some commentary included, on depositional environments. Some are marine, and some are not.
Moose
------------------
BS degree, geology, '83
Professor, geology, Whatsamatta U
Old Earth evolution - Yes
Godly creation - Maybe

Replies to this message:
 Message 34 by Tranquility Base, posted 05-23-2002 1:28 AM Minnemooseus has replied

Tranquility Base
Inactive Member


Message 33 of 64 (10270)
05-23-2002 1:23 AM
Reply to: Message 31 by Joe Meert
05-23-2002 12:47 AM


Joe, something 'deterministic' might at least demonstrate correct trends - explain, at least the trend and fact of the global sea level changes for example over time.
And before that, what are the qualitative mechanisms? What's the consensus? Why do you expect creatnioists to have detialed answers when thousands of you guys don't for your model?
I know very well about the detailed (very nice actually) work done by geologists from Hutton to Lyell to Holmes to you guys etc. What I am, gradually (I'd do it quicker but I'm already hogging this site too much) trying to express is that I think all of that beautiful work is in fact consistent with flood geology and didn't actaully prove how the geological column got there.
IMO Hutton and Lyell (and the rest of you) have primarily demonstrated that almost all features carved out of the vast beds of the column could have been done gradually over eons. I agree. We also think it could have happened rapidly out of soft sediments.
I will categorically state that 99% of the books I have read on 'Origin of Sedimentary Rocks' do not actaully cover the issue of 'Origin of the Geological Column'. There are a dozen erosional/depostional environments that in great detail are linked in terms of ancient/current.
On the critical issue of where did the vast beds (ie not the erosional feauteres but the alyers themselves) that characterize the continental deposits there is near silence.
On a few pages of these texts (Shelley, 1996 for example - see my opening post) we find the admission that there is no modern analog for the formation of these vast beds. I have no problem with that (but boy did I have to do a lot of reading to find that out). I can appreciate that due to plate tectonics we live in a different world. It is still interesting that the vast beds of the geological column are not forming anywhere on this planet as they have previously.
It is true that Lyell made all of his claims without knowing this is it not? How did he account for lack of analogs? Lyell never really did prove where the vast beds of the geolgocial column came from and I don't think that contemporary scientists have either. It is a nice theory that sounds right. I'll grant that.
[This message has been edited by Tranquility Base, 05-23-2002]

This message is a reply to:
 Message 31 by Joe Meert, posted 05-23-2002 12:47 AM Joe Meert has replied

Replies to this message:
 Message 35 by Joe Meert, posted 05-23-2002 2:16 AM Tranquility Base has replied
 Message 43 by edge, posted 05-23-2002 12:04 PM Tranquility Base has not replied

Tranquility Base
Inactive Member


Message 34 of 64 (10271)
05-23-2002 1:28 AM
Reply to: Message 32 by Minnemooseus
05-23-2002 12:48 AM


Thanks Moose, I'll check it out. In the past I have found these sites to cover descriptive isues rather than deterministic ones. You saw my point that I am particualrly interested in the GC = Geological Column, not just the Grand Canyon? But the 'Canyon is not a bad example of it.

This message is a reply to:
 Message 32 by Minnemooseus, posted 05-23-2002 12:48 AM Minnemooseus has replied

Replies to this message:
 Message 37 by Minnemooseus, posted 05-23-2002 3:02 AM Tranquility Base has replied

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


Message 35 of 64 (10273)
05-23-2002 2:16 AM
Reply to: Message 33 by Tranquility Base
05-23-2002 1:23 AM


quote:
Originally posted by Tranquility Base:
[B]Joe, something 'deterministic' might at least demonstrate correct trends - explain, at least the trend and fact of the global sea level changes for example over time. [/QUOTE]
JM: And it has. For example, we can correlate sea level drops in the more recent past with glaciations. We can correlate sea level rise (say Cretaceous) with increased spreading rates (see discussion of this mechanism at http://gondwanaresearch.com/oceans.htm. We can correlate sea level drops in the past with glacial epochs. So, I don't know why you insist that geologists don't have a good idea of how these changes occurred. We do.
quote:
And before that, what are the qualitative mechanisms? What's the consensus? Why do you expect creatnioists to have detialed answers when thousands of you guys don't for your model?
JM: Yes, if they are going to insist that their model is better, then it should explain everything conventional geology does and go one better. As of today, they are not even publishing this material in places where their peers can review it.
quote:
I know very well about the detailed (very nice actually) work done by geologists from Hutton to Lyell to Holmes to you guys etc. What I am, gradually (I'd do it quicker but I'm already hogging this site too much) trying to express is that I think all of that beautiful work is in fact consistent with flood geology and didn't actaully prove how the geological column got there.
JM: Well, here I go repeating myself like I said I would try to avoid---but here goes. WHERE? What evidence have they published? All we get is assertion. No data. So, where's the data published? If I do a search on GEOREF, who's name should I look for?
quote:
IMO Hutton and Lyell (and the rest of you) have primarily demonstrated that almost all features carved out of the vast beds of the column could have been done gradually over eons. I agree. We also think it could have happened rapidly out of soft sediments.
JM: You keep painting this false picture of geology despite the fact that we have told you that processes vary over time. Some features are fast (volcanic eruptions) and some are slow (the creation of birdfoot deltas). Soft sediment deformation, when it occurs, is quite obvious in the field. The problem with the soft-sediment idea is the presence of very striking brittle features in the rocks (such as joints and fractures) which parellel deformation in the mountain belts where we find them. S
quote:
I will categorically state that 99% of the books I have read on 'Origin of Sedimentary Rocks' do not actaully cover the issue of 'Origin of the Geological Column'. There are a dozen erosional/depostional environments that in great detail are linked in terms of ancient/current.
JM: I suspect that they do, but not in the manner that you desire. Frankly speaking, I am not sure what you want since the origin of the geologic column is discussed in nearly every elementary book I have ever read!
quote:
On the critical issue of where did the vast beds (ie not the erosional feauteres but the alyers themselves) that characterize the continental deposits there is near silence.
JM: How do you figure? I am preparing a proposal on a 5000 meter thick sequence of sedimentary strata in India. I've no less than 30 references discussing the formation of these sedimentary units. The references discuss the provnenance of the sediments, the paleocurrent directions, the depositional environments and even the rates of deposition. To assert that such things are not discussed is absurd in the highest degree.
quote:
On a few pages of these texts (Shelley, 1996 for example - see my opening post) we find the admission that there is no modern analog for the formation of these vast beds.
JM: What vast beds? The entire geologic column? Why would something that took millions of years to form have a modern analogue (i.e. the last 100 years?). However, we find sediments accumulating and dewatering in the Mississippi delta, we find carbonates being formed in the Bahamas (UF runs a field trip there yearly), we find conglomeratic units being deposited in high energy river systems. We find glaciers depositing moraines. We see dunes forming cross beds in modern deserts. To assert that there are no modern analogues is also absurd in the highest degree.
quote:
I have no problem with that (but boy did I have to do a lot of reading to find that out). I can appreciate that due to plate tectonics we live in a different world. It is still interesting that the vast beds of the geological column are not forming anywhere on this planet as they have previously.
JM: You mean you had to search high and low to find one quotation that hints at what you think is a problem? OK.
quote:
It is true that Lyell made all of his claims without knowing this is it not?
JM: HUH? I don't understand this sentence.
Lyell never really did prove where the vast beds of the geolgocial colum ncame from and I don't think that contemporary scientists have either. It is a nice theory that sounds right. I'll grant that
JM: As you well know, science is not about 'proof'. Absolutes fall in the religious realm (and even those are relative between religions!)
Cheers
Joe Meert

This message is a reply to:
 Message 33 by Tranquility Base, posted 05-23-2002 1:23 AM Tranquility Base has replied

Replies to this message:
 Message 36 by Tranquility Base, posted 05-23-2002 3:02 AM Joe Meert has not replied

Tranquility Base
Inactive Member


Message 36 of 64 (10274)
05-23-2002 3:02 AM
Reply to: Message 35 by Joe Meert
05-23-2002 2:16 AM


OK Joe, so I'm getting this picture of sea level changes causing oceans to inundate continents gradually generating sediments, fine.
I am finding this helpful. What I can't find in the entire origin of sedimentary rock section of our geology library is the correlation and timing of the sea level risings that generated these vast beds. I guess I need to read glaciation for this? Is that the consensus then?
And the 8 or so inundations were due to glaciers melting and refreezing? If much of Nth America was under water this would have correlated with the rest of the world right? OK - I must admit I don't understand why this hasn't been covered in the books I've looked at. Even that tourist web site on the Grand Canyon that Moose gave me has more information on the origin of the geological column than Pettijohn and Shelley IMO.
OK, what you've said is sort of what I've thought except I didn't know that glaciation was the mechanism of sea level movements. So how does your model account for:
(i) The vast continental layered non-marine beds? We have land plant and land animal fossils throughout certain layers, eg in neat Grand Canyon foramtions such as the Hermit or Supai. These strata are neat parallel stacked terrestial beds aren't they? How could this have occurred gradually - there's no evidnce for erosion in between depositional events?
(ii) Why are the marine beds so flat?

This message is a reply to:
 Message 35 by Joe Meert, posted 05-23-2002 2:16 AM Joe Meert has not replied

Replies to this message:
 Message 39 by Minnemooseus, posted 05-23-2002 3:30 AM Tranquility Base 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 37 of 64 (10275)
05-23-2002 3:02 AM
Reply to: Message 34 by Tranquility Base
05-23-2002 1:28 AM


Ah, things are clearer now. I was under the impression that the "GC" in both topics was referring to the sediments of the Grand Canyon. Did you add that clarification, back in message 1, by edit, or was it always there? Whatever - no need to answer.
Also note, there is another geologic column topic at:
http://www.evcforum.net/cgi-bin/dm.cgi?action=page&f=11&t=13&p=7
The Moose formerly known as "Confused"
------------------
BS degree, geology, '83
Professor, geology, Whatsamatta U
Old Earth evolution - Yes
Godly creation - Maybe

This message is a reply to:
 Message 34 by Tranquility Base, posted 05-23-2002 1:28 AM Tranquility Base has replied

Replies to this message:
 Message 38 by Tranquility Base, posted 05-23-2002 3:12 AM Minnemooseus has not replied

Tranquility Base
Inactive Member


Message 38 of 64 (10276)
05-23-2002 3:12 AM
Reply to: Message 37 by Minnemooseus
05-23-2002 3:02 AM


I edited it in when I realized the misunderstanding.

This message is a reply to:
 Message 37 by Minnemooseus, posted 05-23-2002 3:02 AM Minnemooseus has not replied

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


Message 39 of 64 (10277)
05-23-2002 3:30 AM
Reply to: Message 36 by Tranquility Base
05-23-2002 3:02 AM


quote:
And the 8 or so inundations were due to glaciers melting and refreezing? If much of North America was under water this would have correlated with the rest of the world right? OK - I must admit I don't understand why this hasn't been covered in the books I've looked at.
The cause of the sea transgressions onto the continents is believed to be caused by increased spreading rates at mid-ocean ridges, which displaces water out of the ocean basins onto the continents. I presume this is covered in the linked site in Joe's previous posting, although, as I type this, the links isn't working.
(added by edit: I'm confident that these transgressions and regressions are also reflected in the deposits elsewhere in the world. I don't have anything to cite to support that statement, but there must be about a zillion pages published on the matter
- end edit).
Sea level fluxuations from glacial effects are, in comparison, relatively minor.
quote:
Even that tourist web site on the Grand Canyon that Moose gave me has more information on the origin of the geological column than Pettijohn and Shelley IMO.
I think there are (at least) two uses of the term "geologic column". The first (and perhaps most proper) is the illustration showing the time-stratagraphic designations: Precambrian, Paleozoic, Mesozoic, Cenezoic, with all their divisions and subdivisions.
The second is the rocks themselves. For that purpose, I think the term "stratagraphic section" might be much better. And there is no such thing as the standard stratagraphic section. Everywhere, the section is different. Maybe the differences are small, but as geographic seperation increases, also do the differences increase.
quote:
OK, what you've said is sort of what I've thought except I didn't know that glaciation was the mechanism of sea level movements. So how does your model account for:
(i) The vast continental layered non-marine beds? We have land plant and land animal fossils throughout certain layers, eg in neat Grand Canyon foramtions such as the Hermit or Supai. These strata are neat parallel stacked terrestial beds aren't they? How could this have occurred gradually - there's no evidnce for erosion in between depositional events?
This requires a more detailed answer than I'm prepared to give at the moment. Will try to get back, if someone else doesn't beat me to it.
quote:
(ii) Why are the marine beds so flat?
They are flat, until some sort of tectonic action deforms them. In some areas, marine sediments are tilted, or tipped up on end, or even overturned, or badly contorted, or in other ways all mangled up.
I gotta get to bed,
Moose
[This message has been edited by minnemooseus, 05-23-2002]

This message is a reply to:
 Message 36 by Tranquility Base, posted 05-23-2002 3:02 AM Tranquility Base has replied

Replies to this message:
 Message 40 by Tranquility Base, posted 05-23-2002 3:56 AM Minnemooseus has replied

Tranquility Base
Inactive Member


Message 40 of 64 (10278)
05-23-2002 3:56 AM
Reply to: Message 39 by Minnemooseus
05-23-2002 3:30 AM


Thanks Moose.
Sea-floor spreading casues transgressions. I guess because the floor gradually folds up and displaces the water. Have I got that right? What about the regressions? Would that be delayed subduction under contiental plates? Have I got that right?
I'll look forward to your answer to the non-marine beds issue.
To my layman's eyes the typical marine strata of the geolgoical column look too flat and lacking in typial sea-floor features to be sea floor habitats. Obviously we feel they are better explained by catastroohpic sedimentaiton. I know this is an old quote (1957) but it does state in a mainstream publication what I can see with my eyes:
quote:
"the ocean bottom is subject to too many disturbances to permit any kind of gradual undisturbed accumulation."
Edwin L. Hamilton: "The Last Geographic Frontier: The Sea Floor," Scientific Monthly, Vol. 85, Dec. 1957, p. 296.
[This message has been edited by Tranquility Base, 05-23-2002]

This message is a reply to:
 Message 39 by Minnemooseus, posted 05-23-2002 3:30 AM Minnemooseus has replied

Replies to this message:
 Message 41 by Minnemooseus, posted 05-23-2002 4:32 AM Tranquility Base 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 41 of 64 (10279)
05-23-2002 4:32 AM
Reply to: Message 40 by Tranquility Base
05-23-2002 3:56 AM


quote:
Sea-floor spreading casues transgressions. I guess because the floor gradually folds up and displaces the water. Have I got that right? What about the regressions? Would that be delayed subduction under contiental plates? Have I got that right?
Don't forget Joe's page - I assume it will be back available sometime. The increased spreading rate effect/affect has been covered to some degree elsewhere, buried in some topic. I really don't understand the details (would like a good reference myself), but seemingly the increased rate causes (maybe?) an oceanic crustal thickening (maybe not?). Also, I belive there might be some sort of boyancy effect, because of increased crustal temperature, and/or mantle convection currents, and/or... Let's take a look at Joe's page.
The sea regression affect is when the transgressive effect end.
An oversimplification, I'm sure.
quote:
I'll look forward to your answer to the non-marine beds issue.
quote:
To my layman's eyes the typical marine strata of the geolgoical column look too flat and lacking in typial sea-floor features to be sea floor habitats
You are confusing deposition upon oceanic crust with deposition upon continental crust, under a transgressed sea.
About the only oceanic sediment you'll find in the continental geological record is stuff that has been obducted(sp?) (opposite of subducted) onto the continents. That stuff gets pretty mangled in the process. I believe some of the sedimentary rocks of the San Francisco, CA area are such. It's often referred to as "melange" (Joe, please correct me if I'm wrong).
There are instances where the oceanic crust ends up incorporated into the continents. I believe at Cyprus is the most prominent example. There you get what is called an "ophiolite sequence" Pillowed basalts on top of "sheeted" basaltic dikes (dikes intruded by dikes...), on top of other oceanic crust/mantle rocks. Enough said about that.
Now, I'm going to bed, before I see another message from you!
Moose
------------------
BS degree, geology, '83
Professor, geology, Whatsamatta U
Old Earth evolution - Yes
Godly creation - Maybe
[This message has been edited by minnemooseus, 05-23-2002]

This message is a reply to:
 Message 40 by Tranquility Base, posted 05-23-2002 3:56 AM Tranquility Base has replied

Replies to this message:
 Message 42 by Joe Meert, posted 05-23-2002 10:58 AM Minnemooseus has not replied
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Joe Meert
Member (Idle past 5680 days)
Posts: 913
From: Gainesville
Joined: 03-02-2002


Message 42 of 64 (10287)
05-23-2002 10:58 AM
Reply to: Message 41 by Minnemooseus
05-23-2002 4:32 AM


A couple of points.
(1) The link is working provided I type it in correctly! It's here
(2) Sea level changes have several different amplitudes and glaciation is only one of them.
(3) Dynamic topography caused by increased spreading rates is well known from the Cretaceous. This is the so-called Cretaceous superplume event by Larson and others.
(4) The variations in temperature of the mantle impose a shape to the geoid which creates long wavelength geoid lows over subduction zones and highs over ridges. As continents move towards the geoid lows, they may become inundated. This is discussed to some degree here; however also see Gurnis 1992 (Science 255, 1556-1558).
You took the word glacial and ran with it, but please note that I discussed it among other scenarios in my post.
(5) Why are the beds flat? Well, because of gravity. Particles tend to settle in layers (try it). I think the picture you imagine in your head is somewhat simplistic. For example, even on a sloped surface, the sediments will accumulate in horizontal layers although the layers will 'pinch out' up slope. A simple picture of this is shown below:
(6) I've noted a few problems with the creationist 'models' in the piece on the ocean floor, but there are others. For example, creationist's have no answers for the many pre-Pleistocene glacial deposits other than to assert they don't exist (or are misindentified).
(7) Sedimentation and the processes of sedimentation for NEARLY all types of rocks have modern analogues that are described in the literature. Here are a few references:
Deepwater channel systems in Turkey as a comparative architectural analogue for sinuous depositional channel systems in high-resolution 3-D seismic Faulkenberry, Laura; Kneller, Ben; Peakall, Jeff; Cronin, B T SO: AAPG Bulletin, vol.85, no.11, pp.2050, Nov 2001
Sediment"-cement relationships in a Pleistocene speleothem from Italy; a possible analogue for "replacement" cements and Archaeolithoporoella in ancient reefs Kendall, Alan C; Iannace, Alessandro Sedimentology, vol.48, no.3, pp.681-698, Jun 2001
The effects of surface area, grain size and mineralogy on organic matter sedimentation and preservation across the modern Squamish Delta, British Columbia; the potential role of sediment surface area in the formation of petroleum source rocks Adams, Rupert S; Bustin, R Marc International Journal of Coal Geology, vol.46, no.2-4, pp.93-112, May 2001
Gypsum salina-coral reef relationships during the last interglacial (marine isotopic stage 5e) on the Egyptian Red Sea coast; a Quaternary analogue for Neogene marginal evaporites?
AU: Orszag-Sperber, F; Plaziat, J C; Baltzer, F; Purser, B H
SO: Sedimentary Geology, vol.140, no.1-2, pp.61-85, Apr 2001
Glacier surging as a control on the development of proglacial, fluvial landforms and deposits, Skeidararsandur, Iceland
AU: Russell, A J; Knight, P G; van Dijk, T A G P
SO: Global and Planetary Change, vol.28, no.1-4, pp.163-174, Feb 2001
Morphology and sedimentology of a giant supraglacial, ice-walled, jokulhlaup channel, Skeidararjokull, Iceland; implications for esker genesis Russell, A J; Knudsen, O; Fay, H; Marren, P M; Heinz, J; Tronicke, J Global and Planetary Change, vol.28, no.1-4, pp.193-216, Feb 2001
The Gulf of Carpentaria as a modern tectonic and eustatic analogue for the Illinois Basin during the Pennsylvanian Gluskoter, Hal J; Edgar, N Terence; Cecil, C Blaine; Dulong, Frank T; Damberger, Heinz H Abstracts with Programs - Geological Society of America, vol.33, no.6, pp.55, 2001
The provenance and facies architecture of Upper Triassic fluvo-lacustrine deposits from the UK; a modern analogue Clarke, Paul R
SO: AAPG Bulletin, vol.84, no.11, pp.1862, Nov 2000
Sandstone sheets associated with deep-water channels; three analogue candidates for HARPS in Turkish Eocene exposures with different origin, external geometry and connectivity Cronin, Bryan T; Hurst, Andrew AAPG Bulletin, vol.84, no.9, pp.1415, Sep 2000
Cheers
Joe Meert

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 Message 41 by Minnemooseus, posted 05-23-2002 4:32 AM Minnemooseus has not replied

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 Message 46 by Tranquility Base, posted 05-23-2002 8:44 PM Joe Meert has replied

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


Message 43 of 64 (10292)
05-23-2002 12:04 PM
Reply to: Message 33 by Tranquility Base
05-23-2002 1:23 AM


quote:
Originally posted by Tranquility Base:
IMO Hutton and Lyell (and the rest of you) have primarily demonstrated that almost all features carved out of the vast beds of the column could have been done gradually over eons. I agree. We also think it could have happened rapidly out of soft sediments.
Let me get this straight: you say that the erosional features that we see on the surface of the earth were cut in soft sediments?
Actually, you statement might be correct ... if the sediments were soft, they could indeed be carved very quickly. The problem is that there is ample evidence that they WERE NOT soft.
quote:
I will categorically state that 99% of the books I have read on 'Origin of Sedimentary Rocks' do not actaully cover the issue of 'Origin of the Geological Column'. There are a dozen erosional/depostional environments that in great detail are linked in terms of ancient/current.
First of all, a book dedicated to sedimentation may not cover erosion of sedimentary ROCKS. They generally talk about transport deposition and lithification of sediments. I checked my sedimentology books and the do not say much about erosion and geomorphology, either. Why do you think that is?
Second, the formation of the geological column is not just sedimentation. It is also magmatism, erosion and tectonics. You seem very confused on this point. Perhaps if you had a little better background you would realize that sedimentation is not necessarily the same thing as erosion.
quote:
On the critical issue of where did the vast beds (ie not the erosional feauteres but the alyers themselves) that characterize the continental deposits there is near silence.
What? I have read over my texts here and find lots of information on source rocks, transport, depositional features and lithification. You are being silly here. Here are the headings for Ch. 6 of Origin of Sedimentary Rocks:
Six: Facies Models
General Principles
Paleocurrents
Paleohydraulics
Environments
Classification of Facis Models
Alluvial Fan Model
Alluvial Model
Fluvial Model
Deltaic Model
Barrier Model
Offshore Shoal
Turbidite - Deep Basin
Conclusion
And that is just Chapter 6. Ch. 12 is on the Origin of Limestones. Ch. 20 is on Major External Controls of Sedimentation. Ch. 2 is on The Geologic Cycle.
Do you wish to reconsider you statement that these things are not addressed?
quote:
On a few pages of these texts (Shelley, 1996 for example - see my opening post) we find the admission that there is no modern analog for the formation of these vast beds.
What are 'vast beds'? Which vast beds are you talking about? Please give us a quote.
quote:
I have no problem with that (but boy did I have to do a lot of reading to find that out).
I daresay you misinterpreted whatever you read. Please document.
quote:
I can appreciate that due to plate tectonics we live in a different world. It is still interesting that the vast beds of the geological column are not forming anywhere on this planet as they have previously.
LOL! I reiterate my question: "What vast beds are you talking about?"
quote:
It is true that Lyell made all of his claims without knowing this is it not?
No. That is because there are modern analogs for the beds that he saw. Are you saying that there are no coral reefs today? No beach sands? No deltaic deposits? No fluvial sedimentary systems? No glacial moraines? No shale basins? No desert dunes? I think you remain confused.
quote:
How did he account for lack of analogs? Lyell never really did prove where the vast beds of the geolgocial column came from and I don't think that contemporary scientists have either.
Utter silliness. Provenance is an integral part of strtigraphy. Yes, after 300 years of stratigraphic studies, we haven't even thought about where the sediments came from. We've just been waiting for TB to come along and point out this deficiency. TB, just because you don't understand something doesn't mean that it hasn't been done.
Can you please explain what you mean by 'vast deposits' and give us an example of a vast deposit? Perhaps that would help clear things up. Also explain what you mean by 'where the vast beds came from.'
[This message has been edited by edge, 05-23-2002]

This message is a reply to:
 Message 33 by Tranquility Base, posted 05-23-2002 1:23 AM Tranquility Base has not replied

TrueCreation
Inactive Member


Message 44 of 64 (10295)
05-23-2002 12:32 PM
Reply to: Message 14 by Mister Pamboli
05-22-2002 9:21 PM


"All part of the rough-and-tumble. As long as it doesn't turn nasty, it's half the fun of the boards. You should see what poor TC has to put up with!"
--It sure is, though I find it quite amusing much of the time. Its all part of the routine here, someone makes an assertion, itterates it all around the board pre-discussion. On to the discussion, the refutation, etc. But then when evident conclusions have been made, or the opponent obviously with-draws, I get to go look back at all the previous posts and silently laugh the crap out of myself!
[No pun intended]
--Sorry about the spelling, quick post, no spell checker.
------------------

This message is a reply to:
 Message 14 by Mister Pamboli, posted 05-22-2002 9:21 PM Mister Pamboli has not replied

Tranquility Base
Inactive Member


Message 45 of 64 (10309)
05-23-2002 8:27 PM
Reply to: Message 41 by Minnemooseus
05-23-2002 4:32 AM


Thanks Moose. I'm talking about the marine beds that are presently on continents (OK - not obducted oceanic crust). I see now that I shouldn't refer to these as oceanic because the crust types are qualitatively different. In any case they are marine beds - shellfish, corals, fish etc. Eg - much of the Grand Canyon strata: Tonto group, Temple Butt, Redwall and Kaibab. Anyway my point is that these strata, formed by transgressions onto land, although they contain all of these marine organisms in abundance, look too flat and relatively undisturbed to actually be their long term habitats - ie they don't look like any modern day shelf.
I'm genuinely intreted in how the transgressions/regressions occured. So transgressions occurred due to more rapid build up at the mid-oceanic ridges.
What about my simple idea (based on what you've told me so far) of delayed subduction of oceanic plates under continental plates? Wouldn't this explain the data? You have semi-continuous sea-floor spreading at mid-oceanic ridges. This causes the regression onto continents via displacement of water by folded oceanic crust. When enough pressure has built up at the continental/oceanic plate boundary subduction of the ocenaic plate under the continental plate begins and this leads to regression? This clearly would occur in cycles that we know occured from the stratigrphic reocrd. I'm wondering whether this might be the fundamental process occuring? Is anything like that what the consensus view is anybody?

This message is a reply to:
 Message 41 by Minnemooseus, posted 05-23-2002 4:32 AM Minnemooseus has not replied

Replies to this message:
 Message 47 by Joe Meert, posted 05-23-2002 8:53 PM Tranquility Base has not replied

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