Understanding through Discussion


Welcome! You are not logged in. [ Login ]
EvC Forum active members: 89 (8843 total)
Current session began: 
Page Loaded: 06-25-2018 3:27 PM
273 online now:
DrJones*, kjsimons, NoNukes, PaulK, Phat (AdminPhat), ringo, Tangle (7 members, 266 visitors)
Chatting now:  Chat room empty
Newest Member: MrTim
Post Volume:
Total: 834,327 Year: 9,150/29,783 Month: 1,397/1,977 Week: 90/445 Day: 36/54 Hour: 1/2


Thread  Details

Email This Thread
Newer Topic | Older Topic
  
RewPrev1
...
8687
88
8990
...
193NextFF
Author Topic:   Evolution. We Have The Fossils. We Win.
Percy
Member
Posts: 17361
From: New Hampshire
Joined: 12-23-2000
Member Rating: 2.1


Message 1306 of 2886 (829667)
03-11-2018 9:04 PM
Reply to: Message 1298 by Faith
03-10-2018 7:08 PM


Re: A knife-edge thick contact is NOT an inch thick
Here's another image of the Coconino/Hermit contact, this one from a little closer:

Note that it labels the entire inch-wide something as the contact, and that it is just as vertical as the rest of the rock face. It is not "knife-edge tight," but it is certainly a sharp contact.

This is from the paper Paleozoic stratigraphy of part of northwestern Arizona. I'm unable to get to the paper itself, so I can't get more detail. This quote comes via a Google Scholar search, and without more context a conclusive interpretation isn't possible, but it seems to imply that the contact between the Coconino and the Hermit is made of sandstone, which would make it part of the Coconino Sandstone, not the Hermit Shale:

quote:
The upper contact of the Hermit formation with the Coconino sandstone is abrupt and is marked
by a sharply defined line separating pink and gray sandstones.

--Percy


This message is a reply to:
 Message 1298 by Faith, posted 03-10-2018 7:08 PM Faith has responded

Replies to this message:
 Message 1307 by Faith, posted 03-11-2018 10:56 PM Percy has responded
 Message 1308 by herebedragons, posted 03-11-2018 11:11 PM Percy has responded

    
Faith
Member
Posts: 28588
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.0


Message 1307 of 2886 (829669)
03-11-2018 10:56 PM
Reply to: Message 1306 by Percy
03-11-2018 9:04 PM


Re: A knife-edge thick contact is NOT an inch thick
Note that it labels the entire inch-wide something as the contact, and that it is just as vertical as the rest of the rock face. It is not "knife-edge tight," but it is certainly a sharp contact.

The arrow is indeed ambiguously placed but I can't see this any other way than I saw the others: the black shadowed line is the contact, the rock just beneath it is Hermit, whatever the cause of its appearing lighter. And it still looks like it could be at a slight angle to me.

You are simply not going to find a contact line dividing the bottom of a formation like the Coconino from a tiny portion of itself and if it did there would be another contact line beneath the lower portion of the Coconino dividing it from the Hermit anyway, which is not there. The identifying feature of a contact between two formations like the Hermit and the Coconino is that it does in fact divide the Hermit from the Coconino.

And again, since others have called this contact line remarkably or unusually tight that alone is reason to know the light section is NOT part of the contact line. I'm sure both Paul Garner and Baumgardner have seen this up close and personal and would not misidentify something so obvfious.

This is from the paper Paleozoic stratigraphy of part of northwestern Arizona. I'm unable to get to the paper itself, so I can't get more detail. This quote comes via a Google Scholar search, and without more context a conclusive interpretation isn't possible, but it seems to imply that the contact between the Coconino and the Hermit is made of sandstone, which would make it part of the Coconino Sandstone, not the Hermit Shale:

quote:

The upper contact of the Hermit formation with the Coconino sandstone is abrupt and is marked
by a sharply defined line separating pink and gray sandstones.

But

  • it clearly says the contact is "abrupt" and
  • "marked by a sharply defined line" which certainly doesn't include the lighter part
  • and that it is between the Hermit and the Coconino.
  • If that is sandstone right beneath it, it is part of the Hermit, not the Coconino.
  • It also says it is a different color from the other sandstone, one being gray the other pink, showing that it is not part of the Coconino.
  • It's absurd to think there would be a clear contact within the Coconino at that level rather than dividing the Hermit from the Coconino.

So you would be right about it being a different color and sediment from the Hermit but wrong about everything else.

ABE: And now I see that HBD has posted more information about this which says the Hermit is not shale but sandstone anyway.

Edited by Faith, : No reason given.

Edited by Faith, : No reason given.

Edited by Faith, : No reason given.

Edited by Faith, : No reason given.

Edited by Faith, : No reason given.

Edited by Faith, : No reason given.

Edited by Faith, : No reason given.


This message is a reply to:
 Message 1306 by Percy, posted 03-11-2018 9:04 PM Percy has responded

Replies to this message:
 Message 1329 by Percy, posted 03-12-2018 12:28 PM Faith has responded

    
herebedragons
Member
Posts: 1459
From: Michigan
Joined: 11-22-2009
Member Rating: 2.7


(2)
Message 1308 of 2886 (829671)
03-11-2018 11:11 PM
Reply to: Message 1306 by Percy
03-11-2018 9:04 PM


Re: A knife-edge thick contact is NOT an inch thick
Percy, here is the entire section on the Hermit shale from your reference.

quote:
HERMIT FORMATION (LOWER PERMIAN)

The Hermit "shale" was named by Noble (1922, p. 26) for the red sandstones and siltstones lying between the Coconino sandstone and the Supai formation at Bass Trail. The designation "shale" to the unit is a misnomer, inasmuch as Noble (p. 28) in his description of the type section, used the term sandstone for the compact massive beds and "shale" for the thinly laminated soft beds, which are in reality fine-grained sandstones.

At Bass Trail the Hermit formation is 332 feet thick. At Kanab Canyon, 30 miles northwest of Bass Trail, it is 775 feet thick, according to a section measured by Walcott and compiled by Noble (1922, Pl. XIX). At South Hurricane Cliffs, approximately 32 miles southwest of Kanab Canyon, the formation is 933 feet thick. It decreases slightly in thickness westward and is approximately 700 feet thick at North Grand Wash Cliffs and Pakoon Ridge.

The upper contact of the Hermit formation with the Coconino sandstone is abrupt and is marked by a sharply defined line separating pink and gray sandstones from the conspicuously cross-bedded lower layers of the Coconino sandstone.


The paper is in .htm format, so I don't think I can send it to you unless I copied and pasted it into a Word doc. But I don't think it really has much useful info in it anyway. I quote the relevant part above.

So it looks like, in context, this paper says the grey sandstone is part of the Hermit formation, which is primarily sandstone rather than shale. In this image, it looks like the Coconino sits right on top of the Hermit formation with no intermixing. To me, this suggests that the Hermit was pretty well lithified before the Coconino was deposited. There is also an issue with timing that Whitmore discusses in a paper you referenced earlier in Message 1297. If you PM me an email address, I can send you the paper. Maybe you could also share it with edge and he would be a better peer-reviewer.

But, what I got from Whitmore's paper (Sand injectites ...) is that faulting related to the Bright Angle Fault was responsible for the cracking of the Hermit shale and liquification and injection of Coconino sandstone into the cracks. This means the Coconino was present but not lithified at the time of the faulting but the Hermit was at least partially lithified. The problem Whitmore presents is that the Bright Angle Fault was supposedly active during the Precambrian period and then not again until the Miocene. So that means the Coconino was unlithified for about 200+ million years, which seems unlikely. I am thinking the key is the timing of when the Bright Angel Fault was active. Maybe this is evidence the fault was active during the Permian?

Here is a semi-relevant quote about the contact

quote:
2.3. The basal Coconino homogenized zone and other features

Bedding is easily distinguished throughout the Coconino, but along
Hance Trail, Grandview Trail and the South Fork of Rock Canyon,
lenses of non-bedded structureless sandstone, up to 2.0 meters thick
and 40 m long, rest on the Hermit at the base of the Coconino (Figs. 9
11). The zones are continuous and intimately connected with sand-
filled cracks (Figs. 4E and 10). The Coconino bedding and cross-
bedding in contact with the structureless sandstone, or homogenized
zone, can occur as a sharp contact (Fig. 9), or as distorted bedding
grading upward into normal Coconino cross-beds (right center of
Fig. 11). The homogenized zone occasionally contains bedded
Coconino clasts, with long axes from 2 to 75 cm (Figs. 9 and 11).
Bedding angles inside the clasts are often askew. Along Hance Trail,
features similar to load casts occur at the base of the Coconino. These
features are intimately associated with dozens of shallow, distorted
sand-filled cracks and the homogenized sandstone. The smaller casts
(Fig. 12) are about 810 cm in diameter. One larger cast was found
that was about 50 cm in diameter. It was also directly associated with
a large sand-filled crack.


So it's more about the Coconino than the contact between the Coconino and the Hermit.

The other reference in Message 1297 (Sandstone clast breccias ... )appears to be to an abstract from a conference, so there is no paper associated with it.

HBD


Whoever calls me ignorant shares my own opinion. Sorrowfully and tacitly I recognize my ignorance, when I consider how much I lack of what my mind in its craving for knowledge is sighing for... I console myself with the consideration that this belongs to our common nature. - Francesco Petrarca

"Nothing is easier than to persuade people who want to be persuaded and already believe." - another Petrarca gem.

Ignorance is a most formidable opponent rivaled only by arrogance; but when the two join forces, one is all but invincible.


This message is a reply to:
 Message 1306 by Percy, posted 03-11-2018 9:04 PM Percy has responded

Replies to this message:
 Message 1310 by edge, posted 03-11-2018 11:32 PM herebedragons has not yet responded
 Message 1330 by Percy, posted 03-12-2018 1:19 PM herebedragons has responded
 Message 1332 by Tanypteryx, posted 03-12-2018 1:55 PM herebedragons has not yet responded

  
Faith
Member
Posts: 28588
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.0


Message 1309 of 2886 (829672)
03-11-2018 11:12 PM
Reply to: Message 1305 by jar
03-11-2018 7:09 PM


Re: A knife-edge thick contact is NOT an inch thick
When one layer is deposited on another layer won't the contact between the two layers always be "knife edge" unless there is mixing? Is there even some known process where the contact between two layers could be anything other than a "knife edge"?

The contact lines between many of the different layers have some small amount of erosion which makes them NOT "knife-edge" tight. This particular one is POINTED OUT FOR ITS TIGHTNESS, which certainly suggests it's at least unusual among the contact lines, otherwise there would be no point in singling it out. Percy's weird idea that a contact would be described as "knife-edge" which is really an inch thick is just beyond bizarre.

Edited by Faith, : No reason given.

Edited by Faith, : No reason given.

Edited by Faith, : No reason given.


This message is a reply to:
 Message 1305 by jar, posted 03-11-2018 7:09 PM jar has responded

Replies to this message:
 Message 1314 by jar, posted 03-12-2018 8:05 AM Faith has responded

    
edge
Member
Posts: 4392
From: Colorado, USA
Joined: 01-09-2002
Member Rating: 2.3


Message 1310 of 2886 (829673)
03-11-2018 11:32 PM
Reply to: Message 1308 by herebedragons
03-11-2018 11:11 PM


Re: A knife-edge thick contact is NOT an inch thick
... So it's more about the Coconino than the contact between the Coconino and the Hermit.

Good digging.

It's starting to look like there was some kind of seismic event or events, that liquified the base of the Coconino and caused injection into fractures forming in the Hermit near the Bright Angel Fault. The orientation of the cracks are compatible with the Bright Angel fault, with what appear to be more pronounced on the west side of the Bright Angel (I can't really tell this from the diagram, but the largest certainly is on the west).

The crack formation and the presence of sandstone fragments (which I have not seen, but were mentioned) suggest that lithification was advanced in both units. It also seems to be telling us something about lithification of sandstones in that it can take quite a long time. For instance that might explain why a lot of the Mesozoic sandstones are not really all that hard.

We seem to have come across some interesting stuff.

Anyway, I am not very convinced of Whitmore's conclusions since he is working with a YEC agenda. I could tell by his language in the publications.


This message is a reply to:
 Message 1308 by herebedragons, posted 03-11-2018 11:11 PM herebedragons has not yet responded

Replies to this message:
 Message 1311 by Faith, posted 03-11-2018 11:36 PM edge has responded
 Message 1313 by Tanypteryx, posted 03-12-2018 1:06 AM edge has responded
 Message 1331 by Percy, posted 03-12-2018 1:33 PM edge has responded

  
Faith
Member
Posts: 28588
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.0


Message 1311 of 2886 (829674)
03-11-2018 11:36 PM
Reply to: Message 1310 by edge
03-11-2018 11:32 PM


Re: A knife-edge thick contact is NOT an inch thick
t's starting to look like there was some kind of seismic event or events, that liquified the base of the Coconino and caused injection into fractures forming in the Hermit near the Bright Angel Fault.

This is very much the same interpretation of the sand in the Hermit cracks that a member of Paul Garner's British creationist team is pursuing.


This message is a reply to:
 Message 1310 by edge, posted 03-11-2018 11:32 PM edge has responded

Replies to this message:
 Message 1312 by edge, posted 03-11-2018 11:46 PM Faith has not yet responded

    
edge
Member
Posts: 4392
From: Colorado, USA
Joined: 01-09-2002
Member Rating: 2.3


(2)
Message 1312 of 2886 (829675)
03-11-2018 11:46 PM
Reply to: Message 1311 by Faith
03-11-2018 11:36 PM


Re: A knife-edge thick contact is NOT an inch thick
This is very much the same interpretation of the sand in the Hermit cracks that a member of Paul Garner's British creationist team is pursuing.

That's fine with me.

I'm sure they've already got their conclusions drawn.

Edited by edge, : No reason given.


This message is a reply to:
 Message 1311 by Faith, posted 03-11-2018 11:36 PM Faith has not yet responded

  
Tanypteryx
Member
Posts: 1681
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 2.5


Message 1313 of 2886 (829676)
03-12-2018 1:06 AM
Reply to: Message 1310 by edge
03-11-2018 11:32 PM


Re: A knife-edge thick contact is NOT an inch thick
It's starting to look like there was some kind of seismic event or events, that liquified the base of the Coconino and caused injection into fractures forming in the Hermit near the Bright Angel Fault.

When you say the the base of the Coconino liquified, do you mean it changed behavior and started acting like a liquid due to earthquake vibration?

The crack formation and the presence of sandstone fragments (which I have not seen, but were mentioned) suggest that lithification was advanced in both units. It also seems to be telling us something about lithification of sandstones in that it can take quite a long time. For instance that might explain why a lot of the Mesozoic sandstones are not really all that hard.

Another question this brings to mind, can sandstone form relatively near the surface and without the extreme pressure that we normally see sedimentary rock being subject to? I am just trying to understand the lithification process that captures the cross bedding of sand dunes. Can water passing through the sand initiate a chemical reaction that results in a solid mineral matrix filling some of the space between sand graines?

As a landscape photographer I find myself drawn to places in the SW where crossdedded sandstone is exposed. I have not been to The Wave in Arizona but hope to some day. The places I have made it to offered endlessly varied patterns and textures, but new places are fun.


What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


This message is a reply to:
 Message 1310 by edge, posted 03-11-2018 11:32 PM edge has responded

Replies to this message:
 Message 1316 by jar, posted 03-12-2018 8:17 AM Tanypteryx has acknowledged this reply
 Message 1319 by edge, posted 03-12-2018 9:00 AM Tanypteryx has acknowledged this reply

    
jar
Member
Posts: 30430
From: Texas!!
Joined: 04-20-2004
Member Rating: 1.5


Message 1314 of 2886 (829677)
03-12-2018 8:05 AM
Reply to: Message 1309 by Faith
03-11-2018 11:12 PM


Re: A knife-edge thick contact is NOT an inch thick
Faith writes:

The contact lines between many of the different layers have some small amount of erosion which makes them NOT "knife-edge" tight. This particular one is POINTED OUT FOR ITS TIGHTNESS, which certainly suggests it's at least unusual among the contact lines, otherwise there would be no point in singling it out. Percy's weird idea that a contact would be described as "knife-edge" which is really an inch thick is just beyond bizarre.

Erosion only happens top an exposed surface Faith so layers that show erosion were surfaces that were not buried when the erosion happened.

We have shown you examples of that repeatedly such as fossil river channels that were subsequently filled BUT, and a big BUT, even in those cases the contact layer between the different materials is still "knife edge".

This particular segment is pointed out by the Creationists for the exact same reason they constant misrepresent the bible; it is the dishonest practice of taking things out of context.

You are just continuing to try to con the rubes, palm the pea and misdirect attention from the fact that the Coconino was NOT and cannot have been deposited by any flood.

The area is singled out by the Creationists sites for the very same totally dishonest reason; to misdirect attention from the fact that there has never been a world-wide flood during the time humans existed.


My Sister's Website: Rose Hill Studios My Website: My Website

This message is a reply to:
 Message 1309 by Faith, posted 03-11-2018 11:12 PM Faith has responded

Replies to this message:
 Message 1315 by Faith, posted 03-12-2018 8:13 AM jar has responded

  
Faith
Member
Posts: 28588
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.0


Message 1315 of 2886 (829678)
03-12-2018 8:13 AM
Reply to: Message 1314 by jar
03-12-2018 8:05 AM


Re: A knife-edge thick contact is NOT an inch thickEros
The area is singled out because it's unusual and because it is evidence against millions of years between depositions.

Erosion can occur in the contact between layers from water runoff or tectonic moveme4nt. In any case the erosion that is seen is not what would be found on the surface. What's impossible is that any layer could have been deposited over millions of years.

Edited by Faith, : No reason given.

Edited by Faith, : No reason given.


This message is a reply to:
 Message 1314 by jar, posted 03-12-2018 8:05 AM jar has responded

Replies to this message:
 Message 1317 by jar, posted 03-12-2018 8:20 AM Faith has responded

    
jar
Member
Posts: 30430
From: Texas!!
Joined: 04-20-2004
Member Rating: 1.5


(1)
Message 1316 of 2886 (829679)
03-12-2018 8:17 AM
Reply to: Message 1313 by Tanypteryx
03-12-2018 1:06 AM


Re: A knife-edge thick contact is NOT an inch thick
Tanypteryx writes:

Another question this brings to mind, can sandstone form relatively near the surface and without the extreme pressure that we normally see sedimentary rock being subject to? I am just trying to understand the lithification process that captures the cross bedding of sand dunes. Can water passing through the sand initiate a chemical reaction that results in a solid mineral matrix filling some of the space between sand graines?

Remember that sandstone in particular records a visual recording of time. The sand dunes show evidence of being covered by material moving in a different direction at a later time but while the material is still unlithified.

Looking at the image there does appear to be a layer at the base that is more homogeneous and less differentiated than what is above. That could well be a sign of sand liquification that could be associated with an even before the layers above were deposited. A seismic event during the early intrusion of wind blown sand over an exposed Hermit layer would destroyed the bedding of a layer making it more homogeneous and also filling any open cracks but the continuing desertification would create the later structure we call the Coconino.

Time. Isn't what we are seeing is just yet more evidence of long, long time periods?


My Sister's Website: Rose Hill Studios My Website: My Website

This message is a reply to:
 Message 1313 by Tanypteryx, posted 03-12-2018 1:06 AM Tanypteryx has acknowledged this reply

  
jar
Member
Posts: 30430
From: Texas!!
Joined: 04-20-2004
Member Rating: 1.5


Message 1317 of 2886 (829680)
03-12-2018 8:20 AM
Reply to: Message 1315 by Faith
03-12-2018 8:13 AM


Re: A knife-edge thick contact is NOT an inch thickEros
Faith writes:

The area is singled out because it's unusual and because it is evidence against millions of years between depositions.

Erosion can occur in the contact between layers from water runoff or tectonic moveme4nt. In any case the erosion that is seen is not what would be found on the surface. What's impossible is that any layer could have been deposited over millions of years.

Yes Faith, we know you keep saying that and that you have never provided any reason to think it is evidence against millions of years between depositions.

Sorry Faith but you have nothing except the dogma of your cult.


My Sister's Website: Rose Hill Studios My Website: My Website

This message is a reply to:
 Message 1315 by Faith, posted 03-12-2018 8:13 AM Faith has responded

Replies to this message:
 Message 1318 by Faith, posted 03-12-2018 8:38 AM jar has responded

  
Faith
Member
Posts: 28588
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.0


Message 1318 of 2886 (829682)
03-12-2018 8:38 AM
Reply to: Message 1317 by jar
03-12-2018 8:20 AM


Re: A knife-edge thick contact is NOT an inch thickEros
The evidence is what you see when you look at the surface of the earth now. It looks nothing like what we see between layers of the geo column.
This message is a reply to:
 Message 1317 by jar, posted 03-12-2018 8:20 AM jar has responded

Replies to this message:
 Message 1320 by edge, posted 03-12-2018 9:05 AM Faith has responded
 Message 1322 by jar, posted 03-12-2018 9:11 AM Faith has responded

    
edge
Member
Posts: 4392
From: Colorado, USA
Joined: 01-09-2002
Member Rating: 2.3


(2)
Message 1319 of 2886 (829684)
03-12-2018 9:00 AM
Reply to: Message 1313 by Tanypteryx
03-12-2018 1:06 AM


Re: A knife-edge thick contact is NOT an inch thick
When you say the the base of the Coconino liquified, do you mean it changed behavior and started acting like a liquid due to earthquake vibration?

That is what people are saying and it is supported by the apparent alignment of the fractures with active fault systems such as the Bright Angel.

Another question this brings to mind, can sandstone form relatively near the surface and without the extreme pressure that we normally see sedimentary rock being subject to?

Well, loose sands can have some cohesion due to moisture, but this doesn't give the material real strength. It allows us to build sand castles.

I am just trying to understand the lithification process that captures the cross bedding of sand dunes.

Evidently, it can take a long time for sand to lithify if there is no cementing material in the groundwater. Unfortunately, I am not a sedimentologist, so I'm guessing.

Can water passing through the sand initiate a chemical reaction that results in a solid mineral matrix filling some of the space between sand graines?

Certainly. A lot of the eolian sands are not well cemented, however, and that is why they develop the landscapes that we see. I think that sheer pressure may make a big difference in the formation of stronger rock by producing a silica cement.

Maybe more later.

I might add that this all has nothing to do with the age factor. There are lots of rapid events in geological time.

One last note. I'm wondering if the first layer of sand at the base of the Coconino was actually laid in water. That is pretty common.


This message is a reply to:
 Message 1313 by Tanypteryx, posted 03-12-2018 1:06 AM Tanypteryx has acknowledged this reply

  
edge
Member
Posts: 4392
From: Colorado, USA
Joined: 01-09-2002
Member Rating: 2.3


(2)
Message 1320 of 2886 (829685)
03-12-2018 9:05 AM
Reply to: Message 1318 by Faith
03-12-2018 8:38 AM


Re: A knife-edge thick contact is NOT an inch thickEros
The evidence is what you see when you look at the surface of the earth now. It looks nothing like what we see between layers of the geo column.

That is because you equate the geological column with the Grand Canyon strata which were marine deposits.

So, obviously, you could not see them.


This message is a reply to:
 Message 1318 by Faith, posted 03-12-2018 8:38 AM Faith has responded

Replies to this message:
 Message 1321 by Faith, posted 03-12-2018 9:08 AM edge has responded

  
RewPrev1
...
8687
88
8990
...
193NextFF
Newer Topic | Older Topic
Jump to:


Copyright 2001-2015 by EvC Forum, All Rights Reserved

™ Version 4.0 Beta
Innovative software from Qwixotic © 2018