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Author Topic:   Continuation of Flood Discussion
Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 361 of 1304 (731619)
05-18-2014 9:02 AM


Re: salt basin
Faith writes:
It shows two layers, Pennsylvanian and Mississippian, both limestone, the Pennsylvanian exposed at the surface although that horizontal line I asked about apparently isn't surface, just "datum" so that isn't clear either.
Edge can confirm, but about the layers above the Pensylvanian carbonates, I believe the top layer of the diagram is the actual top layer, and I don't believe Edge was saying that there are layers above that layer today that are not shown on the diagram. I think he was saying that he doesn't know what happened to the layers above, but the undetailed answer is that it was erosion.
I'm not sure what Edge meant about "datum".
Again, Edge can confirm, but I think he presented the diagram to call your attention to the buried fault on the right hand side. This is a fault that occurred during a period when the layers in this region were still being deposited. The Uncompahgre Uplift was tectonic uplift that took place at the same time that the corresponding layers of the Grand Canyon region were being deposited.
As has been described to you over and over again, the world is not tectonically active everywhere at the same time. The last significant earthquake in Los Angeles was in March of this year just a couple months ago, and another could occur at any time. Los Angeles lies near the boundary between two plates and is in a very tectonically active region.
But the last significant earthquake in Missouri was in 1812, and no one's expecting another one anytime soon. Being in the middle of a plate it isn't particularly tectonically active. The Grand Canyon region is also in the middle of a plate. We shouldn't expect to find evidence of a great deal of tectonic activity there, and we don't.
But we do not find a complete absence of tectonic activity either. I've described how the Tapeats was subjected to tectonic movement nearly as great as the uplift experience by the Grand Canyon region. Edge has shown you a buried fault created while the Grand Canyon layers were being deposited. If you look at sedimentary layers nearer plate boundaries instead of in the middle of plates you should find a great number of buried faults. Given that you believe all sedimentary layers were laid down by the flood, the mere fact that buried faults exist falsifies your claim that there was no tectonic activity while they were being deposited.
--Percy

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 362 of 1304 (731620)
05-18-2014 9:23 AM


Re: salt basin
Edge can confirm, but about the layers above the Pensylvanian carbonates, I believe the top layer of the diagram is the actual top layer, and I don't believe Edge was saying that there are layers above that layer today that are not shown on the diagram.
I don't either but he hasn't been clear about what the surface actually is. In any case there would have been the whole stack above it originally as there still is in the GS area.
I think he was saying that he doesn't know what happened to the layers above, but the undetailed answer is that it was erosion.
In which case my explanation of how the massive erosion in the GS-GC area occurred after all the strata were in place would also apply here.
I'm not sure what Edge meant about "datum".
Nor am I.
Again, Edge can confirm, but I think he presented the diagram to call your attention to the buried fault on the right hand side.
Yes, that may be the main feature he had in mind. I also answered that.
This is a fault that occurred during a period when the layers in this region were still being deposited. The Uncompahgre Uplift was tectonic uplift that took place at the same time that the corresponding layers of the Grand Canyon region were being deposited.
That is of course the standard explanation but as I said there is no evidence whatever in that diagram that supports that explanation. In fact what evidence is there at all for that explanation? This or that is said to have occurred in such and such a time period when the only evidence there seems to be is that the phenomenon appears to have affected a particular layer more than others or some such idea, which is very odd logic.
As has been described to you over and over again, the world is not tectonically active everywhere at the same time. The last significant earthquake in Los Angeles was in March of this year just a couple months ago, and another could occur at any time. Los Angeles lies near the boundary between two plates and is in a very tectonically active region.
Uh huh. My claim is that the tectonic activity BEGAN right after or at the end of the Flood, that there was NO tectonic activity during the laying-down of the strata, and I've been doing a pretty good job of making the case for this. What is going on in our time is something else.
But the last significant earthquake in Missouri was in 1812, and no one's expecting another one anytime soon. Being in the middle of a plate it isn't particularly tectonically active. The Grand Canyon region is also in the middle of a plate. We shouldn't expect to find evidence of a great deal of tectonic activity there, and we don't.
Again, what is going on in modern time has nothing to do with my claim that tectonism BEGAN after the strata were all in place, that is, at the end of the Flood.
But we do not find a complete absence of tectonic activity either. I've described how the Tapeats was subjected to tectonic movement nearly as great as the uplift experience by the Grand Canyon region.
I do tend to ignore your posts too, Percy, but my guess would be that this occurred afterward too. Just because a particular layer is particularly affected does not prove that a particular event occurred in the time period associated with that layer.
Edge has shown you a buried fault created while the Grand Canyon layers were being deposited. If you look at sedimentary layers nearer plate boundaries instead of in the middle of plates you should find a great number of buried faults.
Again this is just the typical confusion between time and physical location which riddles establishment geology. Buried faults do NOT prove they occurred in the time period associated with a particular layer. That's silly. They could have occurred at any time afterward but the forces stopped short of faulting the entire stack. ABE: As a matter of fact those that occurred after the rock was lithified might have been less likely to penetrate the whole stack because of resistance to shifting in higher layers. /ABE
Given that you believe all sedimentary layers were laid down by the flood, the mere fact that buried faults exist falsifies your claim that there was no tectonic activity while they were being deposited.
No it doesn't.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.
Edited by Faith, : add a word and remove a comma
Edited by Faith, : remove "that"

  
PaulK
Member
Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


Message 363 of 1304 (731621)
05-18-2014 9:30 AM


Re: salt basin
quote:
Edge can confirm, but about the layers above the Pensylvanian carbonates, I believe the top layer of the diagram is the actual top layer, and I don't believe Edge was saying that there are layers above that layer today that are not shown on the diagram. I think he was saying that he doesn't know what happened to the layers above, but the undetailed answer is that it was erosion.
I think that Edge was only saying that it was unclear what was there today. The datum line represents a past surface, and the diagram isn't meant to show any overlying rock.
The lecture material here gives a lot more info.
Salt Tectonics of the Paradox Basin

  
Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 364 of 1304 (731622)
05-18-2014 9:45 AM


Re: salt basin
PaulK writes:
I think that Edge was only saying that it was unclear what was there today. The datum line represents a past surface, and the diagram isn't meant to show any overlying rock.
The term "datum line" was clear from context. It's just that there's nothing in that diagram indicating that the top line is a datum line, that it's just a line of reference and not an actual surface.
--Percy

  
PaulK
Member
Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


Message 365 of 1304 (731623)
05-18-2014 9:52 AM


Re: salt basin
quote:
The term "datum line" was clear from context. It's just that there's nothing in that diagram indicating that the top line is a datum line, that it's just a line of reference and not an actual surface.
Edge said that it was a datum line. And I'm pretty sure that he is correct and that there are strata not shown. See the link in my previous post for a load more diagrams.

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


Message 366 of 1304 (731624)
05-18-2014 10:52 AM


Re: Musing or rant, not sure which
What is the irregular bricked layer between the Pennsylvanian and Mississippian? Or is the top layer the one labeled "Carbonates" and the word Pennsylvanian actually refers to the layer below it.
Actually, those are Pennsylvanian limestones. The boundary between the Pennsylvanian and Mississippian is the jagged line depicting an unconformity.
Why are the shale, sand and salt, and conglomerate layers on the right side narrow and vertical?
Those represent thick layers of laterally varying sedimentary 'facies' or zones, similar to the offshore zoning we looked at earlier in this thread. What it shows is that there was not a lot of transgression and regression, just continual sedimentation as the basin subided.
Let me try a guess. The Uncompahgre Uplift on the right was the coastline of an ancient sea. The basin wasn't always this deep. The bottom of the deposits of gypsum, salt, shale, sand, silt and conglomerate used to be much higher, but as deposits formed the weight caused the basin to slouched deeper and deeper into the landscape. The conglomerate nearest this coastline is runoff from the uplift. The sand and silt is normal coastline deposits. The shale is normal off-coastline deposits. The salt formed from repeated evaporations of an irregularly regressing sea.
Excellent understanding. Your observation about the depth of the basin is very good for a non-geologist.
The anhydrite gypsum, is that a type of sand? If so then it must represent the opposite coast, but then shouldn't there also be adjacent shale and silt layers?
No, anydrite is the non-hydrated version of gypsum (CaSO4(H2O)). They are both evaporites. In the scheme of things, they tend to precipitate after halite (common salt).

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 367 of 1304 (731625)
05-18-2014 10:57 AM


Re: Musing or rant, not sure which
The basin wasn't always this deep. The bottom of the deposits of gypsum, salt, shale, sand, silt and conglomerate used to be much higher, but as deposits formed the weight caused the basin to slouched deeper and deeper into the landscape.
Yes this makes sense. This unconformity developed over time, long after the Pennsylvanian limestone was laid down.
... The salt formed from repeated evaporations of an irregularly regressing sea.
Or just evaporation over time from one regressing sea.

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


Message 368 of 1304 (731626)
05-18-2014 11:01 AM


Re: salt basin
The term "datum line" was clear from context. It's just that there's nothing in that diagram indicating that the top line is a datum line, that it's just a line of reference and not an actual surface.
Exactly. I struggled with what to call it. To geologists I would say it is a chronostratigraphic datum or horizon. It represents the surface of the earth (as a plane) at a single point in time in geological history. (ETA: In actual geometry the line might be quite sinuouis. We have just straightened it in this type of diagram.)
The purpose of the diagram is to show how the basin evolved, and the thickness of the Pennsylvanian strata. It is not a cross-section.
In this case there is a huge (relatively) section of coarse clastic rocks accumulating at the edge of the Uncompahgre Uplift, during Pennsylvanian time (that would be upper Carboniferous to folks in much of the rest of the world), right in the middle of Faith's Phanerozoic 'quiet' period of no tectonism.
I apologize for presenting such a technical diagram to this group. To me, it's just kind of second nature...
Edited by edge, : No reason given.

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


Message 369 of 1304 (731627)
05-18-2014 11:04 AM


Re: Musing or rant, not sure which
Yes this makes sense. This unconformity developed over time, long after the Pennsylvanian limestone was laid down.
Actually, this diagram says nothing about the post-Pennsylvanian. It is not a cross section.
Or just evaporation over time from one regressing sea.
In this case, there is very little transgression or regression, just minor adjustments to the shoreline on the eastern side of the basin, probably related to periodic uplift of the Uncompahgre.

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


Message 370 of 1304 (731628)
05-18-2014 11:09 AM


Re: salt basin
I think that Edge was only saying that it was unclear what was there today. The datum line represents a past surface, and the diagram isn't meant to show any overlying rock.
Exactly.
The lecture material here gives a lot more info.
Thanks, I'm keeping this one...
ETA: After looking at some of the diagrams, I would call attention to Page 6. It shows the salt piercing one late-Pennsylvanian unit and then into even younger rocks; so it is showing what happened after the Pennsylvanian, as opposed to my earlier diagram. It is more of a cross-section, though certainly generalized.
Edited by edge, : No reason given.

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


Message 371 of 1304 (731629)
05-18-2014 11:24 AM


Re: salt basin
In which case my explanation of how the massive erosion in the GS-GC area occurred after all the strata were in place would also apply here.
Actually, it's exactly the opposite. The Uncompahgre uplift, part of the Ancestral Rockies was being severely eroded. And, as you can see, it is not far from the modern Colorado Plateau and during the tectonism-free period that you posit.
That is of course the standard explanation but as I said there is no evidence whatever in that diagram that supports that explanation. In fact what evidence is there at all for that explanation? This or that is said to have occurred in such and such a time period when the only evidence there seems to be is that the phenomenon appears to have affected a particular layer more than others or some such idea, which is very odd logic.
Then you need to explain why conglomerates are being deposited adjacent to a fault with the east side strongly uplifted during the period that you say is tectonism-free. While the GC area seems to be fairly quiet, there was certainly plenty going on in the region.
Again, what is going on in modern time has nothing to do with my claim that tectonism BEGAN after the strata were all in place, that is, at the end of the Flood.
The geology proves you wrong. Just because you found a nice quiet beach on the Persian Gulf does not mean that there isn't upheaval in the provinces.... (that's an analogy, by the way).
No it doesn't.
So, that's your argument? "No, it doesn't."
When a fault cuts a rock, we can be pretty sure that it is younger than the rock. When the rock 'cuts' the fault off, we can be pretty sure that it is older than the rock. If you have an alternate explanation, I'd love to hear it.

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 372 of 1304 (731630)
05-18-2014 11:29 AM


Re: salt basin
None of this is happening during the "period" you claim it is.

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


Message 373 of 1304 (731631)
05-18-2014 11:33 AM


Re: salt basin
None of this is happening during the "period" you claim it is.
So, you don't actually have an explanation of all of the data.
Actually, that's fine with me.

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 374 of 1304 (731632)
05-18-2014 12:41 PM


Re: salt basin
Fine with me too.
ABE: My point is that your point is wrong, that there is no evidence whatever for ascribing any time period to the phenomena illustrated, that's all an artifact of the Old Earth theory, not borne out by the facts shown in the diagram. /ABE
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

  
Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 375 of 1304 (731633)
05-19-2014 7:50 AM


Re: salt basin
Faith writes:
I do tend to ignore your posts too, Percy...
That might help you feel better, but it's destructive to discussion. You've responded to less than half the posts to you in this thread, and of the rest you've ignored most of what was explained. This is how you've maintained the ignorance necessary to avoid realizing that your ill-conceived ideas violate many known physical laws, are unsupported by any evidence, and don't even follow the Bible.
--Percy

  
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