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Author Topic:   Origin of the Flood Layers
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 265 of 409 (753325)
03-19-2015 9:36 AM


Just a side note. I appreciate Percy's posts because I've been struggling about those things too.
I still do NOT understand how the supposed erosion at the surface is what makes an "unconformity."
As I just wrote to Moose I see the Tapeats-Vishnu photo entirely differently from anybody else, and I continue to see it that way. If edge would mark the photo to indicate how he sees it maybe I'd have a different way of looking at it.
Edge's posts that I haven't yet answered look like they are going to be just about impossible to understand. I'm not looking forward to that struggle.
Edited by Faith, : No reason given.

Replies to this message:
 Message 266 by ThinAirDesigns, posted 03-19-2015 9:41 AM Faith has replied

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


Message 267 of 409 (753332)
03-19-2015 10:43 AM
Reply to: Message 266 by ThinAirDesigns
03-19-2015 9:41 AM


I still do NOT understand how the supposed erosion at the surface is what makes an "unconformity."
Perhaps you could look up the definition of an "unconformity" and then cease to struggle with what one is.
Let me see if I can be clearer: the definitions seem artificial and illogical. Something you use to label a formation but without any clear reason why you are doing so. Most of it is clearly to conform to Old Earth presuppositions, but beyond that they don't seem to have much actual reality that I can hold onto.

This message is a reply to:
 Message 266 by ThinAirDesigns, posted 03-19-2015 9:41 AM ThinAirDesigns has replied

Replies to this message:
 Message 271 by ThinAirDesigns, posted 03-19-2015 11:22 AM Faith has replied

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


Message 269 of 409 (753335)
03-19-2015 11:10 AM
Reply to: Message 248 by edge
03-18-2015 8:25 PM


Looking at this photo again, it looks to me like the sandstone had just plucked the quartz out of the Vishnu before it stopped moving forward over the Vishnu, then slightly receded in the process of hardening so that you can see it holding on to the quartz it had just lifted out of the Vishnu.
What do you mean by the sandstone 'stopped moving forward'?
You are making no sense at all.
That's what it looks like. It looks like a thickly fluid sand{stone} flowed across the Vishnu schist and then ran out of material, came to its end, no more wet fluid pre-sandstone. Like icing on a cake that runs out before you've covered the cake (and that's a good analogy too since if you aren't very careful the icing will pick up chunks of cake and soon be a complete mess), It looks far more like this than it looks like it was eroded back from the schist, IMHO. If you look at the photos I've marked you should at least see what I'm seeing. And I ask you again to please mark a photo yourself so I can see what you are seeing in it.
I've marked the edges of the depressions in the Vishnu which fit the shapes of the quartz stuck in the sandstone. In other words, no erosion had to occur to expose that quartz, that's just the way it was embedded in the Vishnu in the first place:
So, all of these fragmental pegmatites just happened to form in the schist right at the surface where your sandstone lava flow(?) just picked them up and put them back down.
This is just bizarre.
The photo you posted later of the vertical wall of schist with the quartz or pegmatite veins in it shows that a LOT of this veined material occurs "at the surface." And if you will PLEASE try to understand the markings I've made on the photo you may see better what I'm seeing.
And no, it did not "pick them up and put them back down." In the photo they are stuck in the sandstone suspended a little ABOVE the depression or trench where I'm saying it looks like they were originally embedded. It picked them up and held them in that position, it did not put them back down.
PLEASE just consider how I'm seeing it. It DOES make sense even if you disagree with it, and again, PLEASE mark a photo so I can see your different way of seeing it.
Some time back, you also couldn't understand how there could be strain in the uppermost layers of a stack of layers three miles high, that only affected those highest layers because they were stretched more than those lower down, which is to be expected of an entire stack being pushed up over a mounded uplift. But this is perfectly reasonable. Just as my view of the photo above is also reasonable.
Edited by Faith, : No reason given.
Edited by Faith, : correcting quote codes
Edited by Admin, : Fix quote.

This message is a reply to:
 Message 248 by edge, posted 03-18-2015 8:25 PM edge has replied

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 Message 273 by edge, posted 03-19-2015 11:36 AM Faith has replied

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


Message 275 of 409 (753348)
03-19-2015 12:00 PM
Reply to: Message 270 by edge
03-19-2015 11:22 AM


Yes, the colors are enhanced. The true colors are shown in the photographs that I located on line.
OK but that leaves the striping, which is pretty unusual whatever their colors. Where else does that phenomenon appear? Perhaps it does somewhere but that formation in China hit me like something from another planet when I first saw it and I've still not seen anything comparable anywhere else. You said something about photos from Mexico though -- perhaps something similar there?
AND the main thing about the formation in relation to what I've been saying isn't the color anyway but the way the sandstone looks like it was squeezed out of a tube. Nobody ever talks about sandstone as having a viscous quality at any stage of wetness that I know of, but both the Chinese formation and that picture of the Tapeats with the quartz chunks stuck in it suggest something along those lines. So does The Wave, but that's the only other one I can think of.

This message is a reply to:
 Message 270 by edge, posted 03-19-2015 11:22 AM edge has replied

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 Message 289 by edge, posted 03-19-2015 1:55 PM Faith has replied

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


Message 276 of 409 (753353)
03-19-2015 12:06 PM
Reply to: Message 271 by ThinAirDesigns
03-19-2015 11:22 AM


Yes, but that is exactly what is artificial to me. The Old Earth theory is so taken for granted they treat it as equivalent to the spectrum of colors, where of course we know if a color is missing because we know the spectrum is universal.
But it is only theory that says there is a layer missing from the strata, it's all a mental construct invented to accommodate the Old Earth. There are other ways to explain the erosion, it is not the inescapable evidence imputed to it.

This message is a reply to:
 Message 271 by ThinAirDesigns, posted 03-19-2015 11:22 AM ThinAirDesigns has replied

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


Message 278 of 409 (753360)
03-19-2015 12:30 PM
Reply to: Message 274 by JonF
03-19-2015 11:43 AM


You call that smooth?
What are you looking at? The vertical frontal edge of the sandstone that I've outlined looks pretty smooth to me, as opposed to being at all ragged from erosion.
Sandstone doesn't flow. Something in the process of lithification might but it sure seems unlikely that it would be just soft enough to flow and just hard enough to hold a near-vertical edge and just happened to stop right there.
But what is so special about "right there?" You mean that trench I've identified as the source of the quartz chunks? If that's all it is there is no "right there" about it, it's just one of many veins of quartz that happened to be under the forward edge of the Tapeats when it ran out of material.
I wouldn't have expected sandstone to have a viscous stage either, but this photo and the one of the Danxia formation in China certainly suggest something of the sort. Something that occurs during its laying down as a wet sediment, not during lithification.
However, erosion of sandstone more than the underlying harder rock is a perfectly reasonable explanation. Especially see the last picture I posted above. Note the clasts and explain how that all formed.
I wasn't clear what you were seeing in that photo, perhaps you could mark it to bring out what you see there? But I'll get back to that post in a minute.
Close-up of The Great Unconformity with Vishnu Schist below and Tapeats Sandstone above. Quartz clasts rest right at the surface of the unconformity, which represents 1,200 million years of time. Note the small dendrtites that seem to emerge from the quartz clasts on their top side.
Well that proves it's quartz I guess, which is what it looks like.
But I don't see the quartz chunks as "resting" at all. They appear to be stuck in the sandstone, suspended above this depression or trench where it looks to me they were formerly embedded.
[qs] At first I did, but as I kept analyzing the situation I noticed the apparent fit of the clasts in the depression right below them. How they fit is what the yellow lines I drew on the latest photo were meant to show.
I don't see any depressions. I see dark shadows of the clasts.
Look at the forground edge of the "shadow," that's the edge of a depression, it's not a shadow. Also, it is so dark because it's a depression. Wish there was some way to verify this.
and if that's the case then the sandstone itself pulled them out
Wow, maybe we should be using unpowered sandstone instead of electrically powered vacuum cleaners. Apparently sandstone has undetected but exremely powerful suction. Who knew?
Seriously, pulled out? Really? What generated that puling force?
Something to do with the relative looseness of the quartz and the relative stickiness of the sandstone and the dryness and hardness of the schist.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 274 by JonF, posted 03-19-2015 11:43 AM JonF has replied

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


Message 280 of 409 (753364)
03-19-2015 12:40 PM
Reply to: Message 272 by JonF
03-19-2015 11:28 AM


Looks as if the schists image originates at Earthly Musings: Seven Days of Geology and Hiking on the Colorado River in Grand Canyon, about 2/3 of the way down the page, captioned "Close-up of The Great Unconformity with Vishnu Schist below and Tapeats Sandstone above. Quartz clasts rest right at the surface of the unconformity, which represents 1,200 million years of time. Note the small dendrites that seem to emerge from the quartz clasts on their top side"
Yes I already commented on this. I guess if he took the picture then he knows that they are resting right on the surface of the Vishnu, but that does not look like a shadow in the picture to me, it looks like the edge of a depression. Maybe the depression is shallower than it looks, but I can't see it as a mere shadow.
The other picture that shows large clasts also shows them embedded in the sandstone.
You'd need to explain the other pictures more, perhaps mark them to indicate what the descriptions refer to because it isn't obvious to me, and I'm not sure what point you are trying to make with them anyway.

This message is a reply to:
 Message 272 by JonF, posted 03-19-2015 11:28 AM JonF has replied

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


Message 281 of 409 (753366)
03-19-2015 12:43 PM
Reply to: Message 279 by ThinAirDesigns
03-19-2015 12:38 PM


But it is only theory that says there is a layer missing from the strata, it's all a mental construct invented to accommodate the Old Earth.
And that's where you'd be wrong.
Just as the colors of the rainbow are established and identifiable, so are the layers of the earth. Methods of identification are numerous, broad, independent and consistent. The original methods were simple enough that they were developed and done near two centuries ago (by YECs). In the time since, the methods have become more and more detailed, precise and most importantly convergent.
Perhaps a course on how in any field, converging lines of evidence lead to the truth.
It works.
JB
Well, you're good at spieling the party line.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 279 by ThinAirDesigns, posted 03-19-2015 12:38 PM ThinAirDesigns has replied

Replies to this message:
 Message 282 by ThinAirDesigns, posted 03-19-2015 12:51 PM Faith has replied
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Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 283 of 409 (753369)
03-19-2015 12:56 PM
Reply to: Message 273 by edge
03-19-2015 11:36 AM


duplicate
Edited by Faith, : No reason given.

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


Message 284 of 409 (753370)
03-19-2015 12:56 PM
Reply to: Message 273 by edge
03-19-2015 11:36 AM


That's what it looks like. It looks like a thickly fluid sand{stone} flowed across the Vishnu schist and then ran out of material, came to its end, no more wet fluid pre-sandstone.
So, you are saying that the Tapeats Sandstone just ended right at this point? That's fortuitous.
Would somebody please explain the significance of "this point?" All I see is a trench left after the vein of quartz was removed from it. That's how it LOOKS to me. It still looks that way. Somebody will have to show clearly that it's better explained some other way, and probably show me on the photo itself.
Like icing on a cake that runs out before you've covered the cake (and that's a good analogy too since if you aren't very careful the icing will pick up chunks of cake and soon be a complete mess), It looks far more like this than it looks like it was eroded back from the schist, IMHO. If you look at the photos I've marked you should at least see what I'm seeing. And I ask you again to please mark a photo yourself so I can see what you are seeing in it.
It's not obvious to me, nor probably anyone else. And I'm not sure what I can annotate to make it clearer. There is a bedding plane cutting diagonally across the upper third of the photo. I fail to see how this would be preserved in a viscous flow model.
OK, that's something to wonder about. But what, in your opinion, explains that vertical edge of the sandstone in which the quartz is stuck? The one I outlined in yellow a while back.
ABE: Since I would really like to know what you think of that vertical edge, here's the picture again:
What would be wrong with just having sand deposited on top of some pebbles sitting on the Vishnu?
All I can say is that it just doesn't LOOK LIKE that to me. The "pebbles" don't look like they are sitting, they look like they are stuck in the sandstone and suspended above a depression out of which they came.
Do you realize that if this was the end of the Tapeats, then the next layer being deposited on the Vishnu as shown would indicate another unconformity?
No comprendo Senor.
I've marked the edges of the depressions in the Vishnu which fit the shapes of the quartz stuck in the sandstone. In other words, no erosion had to occur to expose that quartz, that's just the way it was embedded in the Vishnu in the first place:
That is not what the evidence shows.
That's what the evidence I just gave you shows until something shows me I'm misreading it.
You have seen a picture of how the quartz/pegmatites actually occur in their original setting. The do not look like clasts laying on a surface composed of Vishnu Schist.
If you are talking about the picture in Message 247, no, they look like veins of quartz in a wall of schist. If something caused the quartz to come out of their veins then they might look like clasts either lying on the schist or stuck in sandstone and not lying on anything.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

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


Message 285 of 409 (753371)
03-19-2015 12:58 PM
Reply to: Message 282 by ThinAirDesigns
03-19-2015 12:51 PM


Turns out what I'm good at is examining, evaluating and appreciating converging lines of evidence.
Yup, very adept at spieling the party line.

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


Message 288 of 409 (753381)
03-19-2015 1:43 PM


HOW I KNOW IT'S A DEPRESSION AND NOT A SHADOW
JonF, Edge:
Here's that picture again with new markings:
The part I've circled in light blue shows it most clearly: It's BLACK underneath the sandstone and there isn't even a clast there to cast a shadow. It is just as black beneath the bottom of the sandstone all the way to the right, which is now outlined in orange, both where there are clasts to cast a shadow and where there are not.
That's a depression or a trench, not a shadow.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

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


Message 290 of 409 (753386)
03-19-2015 2:03 PM
Reply to: Message 289 by edge
03-19-2015 1:55 PM


Thank you for the picture of the formation in Nevada. It's striped like the Chinese formation and curved like the Wave and I hadn't known about it.
The carved formation at the bottom is a different kind of thing than I'm talking about.
I don't think you've said anything to explain the appearance of viscosity in either the Danxia formation -- especially those barrel-shaped forms lying on their side in a row -- or the Tapeats we've been discussing. Neither is "normal tilted bedding."
Jut for reference here again are the barrel shaped forms mentioned:
Thanks anyway.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

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


Message 303 of 409 (753437)
03-19-2015 10:08 PM
Reply to: Message 251 by herebedragons
03-18-2015 10:34 PM


So a couple points about your interpretation...
>That picture was only meant to illustrate clasts from the older layer that had been incorporated into the younger, overlaying layer. It is NOT the big picture of the unconformity...a picture like that wouldn't fit on the screen.
No idea why you are saying this. I'm just dealing with the picture as an interesting picture that doesn't look to me like what you all are finding in it.
And for reference, here's the picture again, with my yellow lines on it:
>The reason that it is more plausible that the surfaces you see in that picture were exposed by erosion is that they are at the bottom of the Grand Canyon. Everything at the bottom of the canyon was exposed by erosion. Why would you think it is more plausible that it is shaped like that because it was once viscous?
Because it LOOKS like it was thick when laid down, and the thick edge with the clasts stuck in it, which is clearly vertical as shown by the shadow on it, doesn't LOOK to me like it was eroded, though JonF keeps insisting it does to him, and also because of the way the clasts seem to me to have come out of the depression in front of them. It's possible the appearance of thickness came as the sand was lithifying, after pulling the clasts out of their seat in the Vishnu I guess. That's the only other possibility I can see.
Sorry to say but neither JonF nor edge seems to be able to read how light and shadow define three dimensional forms, but it happens to be one thing I'm pretty good at. I'm also usually pretty good at spatial relationships.
>Remember, in your scenario, this was covered by the whole stack of Paleozoic sediments that were squeezing the water out of these lower layers. How could they shrink like that while being compressed?
No idea what your last sentence is referring to, but this picture simply doesn't look like my usual scenario. That scenario describes what happened at some point in the GC area due to the uplift as shown on the cross sections, and I don't know where this picture was taken in relation to that, but it does not look to me like the Tapeats ever had a layer above it here, nor does the exposed part of the Vishnu look to me like it did either. Can't see the clasts as the result of erosion due to surface exposure, look clearly to me like they were dislodged by the movement of the sand above.
>Don't you think those depressions that you outlined in yellow look more like running water carved them out rather than the clasts fit in them? There is a good strong source of running water at the bottom of the canyon.
No. The more I look at the picture the more I see it as I've described it.
>If the clasts were part of the Vishnu Schist before this viscous sandstone "plucked them out," how did they get incorporated into the Vishnu in the first place? You already pointed out that they don't look like the surrounding rock.
Edge posted a picture -- Message 247 -- showing a wall of schist with veins of quartz exposed in it -- apparently a normal presentation of Vishnu schist. So I figure the quartz chunks in the picture we are discussing would have been broken out of such a vein here too, with the aid of wet or drying sand that seems to have had a sticky quality to it, at least while it was drying and hardening which I've suggested it did while lying over the quartz vein, then gradually pulling pieces of the quartz with it as it dried and hardened more, shrinking and retracting from the position over the vein. Being a different kind of rock I'd guess that the quartz may be relatively easily loosened from the schist. Since I do think the quartz pieces would fit into the parts of the depression indicated by my lines on the picture I continue to see it this way.
Edge keeps calling the picture a "cross section" yet has not been able to show me what he means by that. I wonder if he thinks the Vishnu surface in the right foreground is vertical as it is in another picture he marked from the same area. Looks to me like the sunlight defines it as horizontal in this picture here, or at least more or less horizontal, as it does the Tapeats to the upper left behind the edge or little wall of the Tapeats where the quartz pieces are stuck. That edge is in shadow, showing its verticality, while the Vishnu in the right foreground is in sunlight.
I was going to try to post a summary of what I have presented so far regarding the Great Unconformity but I just don't have the time right now. Maybe this weekend. In the mean-time maybe you could review my Message 103 from the Evidence that the Great Unconformity did not Form Before the Strata above it. It covers the details regarding the contact between the Tapeats and the basement rocks.
Maybe, but I am very convinced by my own interpretation of this picture and find the dismissive way others deal with it to be discouraging and frustrating, especially since I think they are misreading basic things like light and shadow, verticality vs. horizontality and so on.
And one more thing: "The contact between the Tapeats and the basement rocks" seems to be reduced by some here to the front edge of the Tapeats where the Vishnu begins to be exposed, both edge and JonF referring to the supposed fortuitousness of the Tapeats stopping just "right there" as I see the picture. I would have thought that an unconformity defined by a contact would mean the whole surface of both upper and lower layers where they contact each other.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

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 Message 339 by Admin, posted 03-20-2015 10:33 AM Faith has replied

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


Message 305 of 409 (753439)
03-19-2015 10:29 PM
Reply to: Message 304 by ThinAirDesigns
03-19-2015 10:26 PM


Again you reduce my comment to a mere definition. Good grief. I've posted dozens of cross sections myself, I know what they are and this picture does NOT look like a cross section.

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