Understanding through Discussion


Welcome! You are not logged in. [ Login ]
EvC Forum active members: 122 (8781 total)
Current session began: 
Page Loaded: 08-19-2017 9:13 AM
382 online now:
Faith, JonF, kjsimons, Meddle, PaulK, Percy (Admin), ramoss, RAZD (8 members, 374 visitors)
Chatting now:  Chat room empty
Newest Member: evilsorcerer1
Post Volume:
Total: 816,407 Year: 21,013/21,208 Month: 1,446/2,326 Week: 782/345 Day: 20/124 Hour: 2/9

Announcements: Reporting debate problems OR discussing moderation actions/inactions


Thread  Details

Email This Thread
Newer Topic | Older Topic
  
RewPrev1
...
910
11
121314Next
Author Topic:   Young earth explanations for Angular Unconformities
Percy
Member
Posts: 15678
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.3


(1)
Message 151 of 202 (796717)
01-03-2017 2:55 PM
Reply to: Message 150 by Faith
01-03-2017 2:13 PM


Faith writes:

And this idea that there were strata above them that eroded away before more strata were deposited, is, as I said, a brand-new idea never before applied in the discussion of these things.

What was it you imagined was eroded away when people described the surface of an angular unconformity as forming due to erosion of the higher portions of the tilted layers?

This understanding of angular conformities has been around forever and is what everyone has been saying. This is from a 1985 geology textbook in a paragraph describing angular unconformities:

quote:
At least four major events are involved in the development of an angular unconformity: (1) an initial period of sedimentation during which the older strata were deposited in a near-horizontal position, (2) a subsequent period of deformation during which the first sedimentrary sequence was folded, (3) development of an erosional surface on the folded sequence of rock, and (4) a period of renewed sedimentation and the development of a younger sequence of sedimentary rocks on the old erosional surface.

Nothing new about it. It's what Hutton surmised when he first saw Siccar Point. Regarding my drawing where I completed the layers of the angular unconformity that had been eroded away:

You included an extremely similar diagram from James Lyle on your blog page titled Angular Unconformities, Part 3: Lyell on how the rocks were tilted:

You had obviously read about geology's very long understanding that the upper portions of tilted layers erode away to form angular unconformities back in 2011 when you wrote that blog page.

--Percy

Edited by Percy, : Typo.


This message is a reply to:
 Message 150 by Faith, posted 01-03-2017 2:13 PM Faith has responded

Replies to this message:
 Message 152 by edge, posted 01-03-2017 6:32 PM Percy has responded
 Message 163 by Faith, posted 01-03-2017 7:46 PM Percy has acknowledged this reply

    
edge
Member
Posts: 3904
From: Colorado, USA
Joined: 01-09-2002
Member Rating: 4.7


Message 152 of 202 (796726)
01-03-2017 6:32 PM
Reply to: Message 151 by Percy
01-03-2017 2:55 PM


Nothing new about it. It's what Hutton surmised when he first saw Siccar Point. Regarding my drawing where I completed the layers of the angular unconformity that had been eroded away:

Assuming continuity of the layers, which is a necessary assumption, a whole lot of the lower sequence has been somehow removed. I'm wondering where, in Faith's scenario, that material went and how it got there.


This message is a reply to:
 Message 151 by Percy, posted 01-03-2017 2:55 PM Percy has responded

Replies to this message:
 Message 153 by Percy, posted 01-03-2017 6:42 PM edge has responded
 Message 155 by Faith, posted 01-03-2017 7:22 PM edge has responded

  
Percy
Member
Posts: 15678
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.3


Message 153 of 202 (796727)
01-03-2017 6:42 PM
Reply to: Message 152 by edge
01-03-2017 6:32 PM


I'm not sure what is meant by "lower sequence", so Faith might not know what is meant, either.

--Percy

Edited by Percy, : Grammar.


This message is a reply to:
 Message 152 by edge, posted 01-03-2017 6:32 PM edge has responded

Replies to this message:
 Message 154 by edge, posted 01-03-2017 7:15 PM Percy has responded

    
edge
Member
Posts: 3904
From: Colorado, USA
Joined: 01-09-2002
Member Rating: 4.7


Message 154 of 202 (796728)
01-03-2017 7:15 PM
Reply to: Message 153 by Percy
01-03-2017 6:42 PM


I'm not sure what is meant by "lower sequence", so Faith not know what is meant, either.

Well, there is one sequence of rocks above the unconformity and another below. I called them 'upper' and 'lower'. The could be called something else if that makes things clearer. I'm open to suggestions.

ETA: in this case, a sequence would be a continuous layering of rocks through time.

Edited by edge, : No reason given.

Edited by edge, : No reason given.


This message is a reply to:
 Message 153 by Percy, posted 01-03-2017 6:42 PM Percy has responded

Replies to this message:
 Message 162 by Percy, posted 01-03-2017 7:41 PM edge has responded

  
Faith
Member
Posts: 25832
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 155 of 202 (796729)
01-03-2017 7:22 PM
Reply to: Message 152 by edge
01-03-2017 6:32 PM


What was it you imagined was eroded away when people described the surface of an angular unconformity as forming due to erosion of the higher portions of the tilted layers?

The uppermost portion of the tilted strata. Not a separate layering of strata.
Duh.

ABE: This post was not meant for edge but for Percy, so I have rewritten it to the right person in Message 163

Edited by Faith, : 63]


This message is a reply to:
 Message 152 by edge, posted 01-03-2017 6:32 PM edge has responded

Replies to this message:
 Message 159 by edge, posted 01-03-2017 7:35 PM Faith has responded

    
Faith
Member
Posts: 25832
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 156 of 202 (796730)
01-03-2017 7:25 PM
Reply to: Message 138 by edge
01-02-2017 10:33 PM


No such thing is present at Siccar or any other place we have discussed. They are ubiquitous in any area that has been tectonized (which would include Faith's scenario for unconformities).

I still want to know how you explain the FACT that the rocks ARE folded despite the absence of this sort of evidence of folding you are talking about.

I also don't think you've answered the question about how rocks get folded or tilted without tectonic pressure.


This message is a reply to:
 Message 138 by edge, posted 01-02-2017 10:33 PM edge has responded

Replies to this message:
 Message 157 by edge, posted 01-03-2017 7:32 PM Faith has responded

    
edge
Member
Posts: 3904
From: Colorado, USA
Joined: 01-09-2002
Member Rating: 4.7


Message 157 of 202 (796731)
01-03-2017 7:32 PM
Reply to: Message 156 by Faith
01-03-2017 7:25 PM


I still want to know how you explain the FACT that the rocks ARE folded despite the absence of this sort of evidence of folding you are talking about.

All I was saying is that in the images we have been looking at, you cannot see a fold axis. I'm certain that they exists and are visible on a larger scale.

However, as we have seen, this does not help you in the least.

I also don't think you've answered the question about how rocks get folded or tilted without tectonic pressure.

I never said otherwise. I said that we do not see the tectonic structures that would be expected for a shear zone between the two packages of rocks. I was very careful in my wording on this.
This message is a reply to:
 Message 156 by Faith, posted 01-03-2017 7:25 PM Faith has responded

Replies to this message:
 Message 160 by Faith, posted 01-03-2017 7:37 PM edge has responded

  
Faith
Member
Posts: 25832
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 158 of 202 (796732)
01-03-2017 7:34 PM
Reply to: Message 147 by edge
01-03-2017 11:34 AM


For rocks to fold I'd still guess there has to be some kind of resistance to the force that is folding them. It doesn't have to be overhead, but in this picture you've posted that is still a big possibility. What are the ages of those rocks in that picture? If they are, say, low in the Paleozoic, then there would have been a deep stack of layers above them just as at Siccar Point. But I'd also surmise the possibility of some resistance between the upper folded block and the flat layers beneath it, giving sliding movement punctuated by jerky stops, based on the fact that the folds are not nice and smooth as they are at Siccar Point, but irregular, suggesting jerky movement.
This message is a reply to:
 Message 147 by edge, posted 01-03-2017 11:34 AM edge has not yet responded

    
edge
Member
Posts: 3904
From: Colorado, USA
Joined: 01-09-2002
Member Rating: 4.7


Message 159 of 202 (796733)
01-03-2017 7:35 PM
Reply to: Message 155 by Faith
01-03-2017 7:22 PM


The uppermost portion of the tilted strata. Not a separate layering of strata.

All I'm saying is that we do not know what was above the actual, original sedimentary rocks that we see at Siccar, based on the images that we have seen.

I also said that a regional investigation would tell us if there were such rocks.

Duh.

Your word, not mine.
This message is a reply to:
 Message 155 by Faith, posted 01-03-2017 7:22 PM Faith has responded

Replies to this message:
 Message 161 by Faith, posted 01-03-2017 7:38 PM edge has not yet responded

  
Faith
Member
Posts: 25832
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 160 of 202 (796734)
01-03-2017 7:37 PM
Reply to: Message 157 by edge
01-03-2017 7:32 PM


I haven't "seen" any of your claims so far. It's all a big cheat. As always, there comes a point when discussions with you devolve into you making unverifiable claims in order to win the argument. This gets old.
This message is a reply to:
 Message 157 by edge, posted 01-03-2017 7:32 PM edge has responded

Replies to this message:
 Message 166 by edge, posted 01-03-2017 7:59 PM Faith has responded

    
Faith
Member
Posts: 25832
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 161 of 202 (796735)
01-03-2017 7:38 PM
Reply to: Message 159 by edge
01-03-2017 7:35 PM


I was talking to Percy, not you. I meant to be anyway, since what I quoted is his constant refrain. Now I see it was from you. Sorry.

He's the one making the dogmatic claim that there were horizontal strata that eroded away, which is the idea I'm saying has never entered into this discussion before.

This is what he said in Message 151 that I thought I was answering:

What was it you imagined was eroded away when people described the surface of an angular unconformity as forming due to erosion of the higher portions of the tilted layers?

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 159 by edge, posted 01-03-2017 7:35 PM edge has not yet responded

Replies to this message:
 Message 165 by Percy, posted 01-03-2017 7:59 PM Faith has not yet responded

    
Percy
Member
Posts: 15678
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.3


Message 162 of 202 (796736)
01-03-2017 7:41 PM
Reply to: Message 154 by edge
01-03-2017 7:15 PM


edge writes:

I'm not sure what is meant by "lower sequence", so Faith not know what is meant, either.

Well, there is one sequence of rocks above the unconformity and another below. I called them 'upper' and 'lower'. The could be called something else if that makes things clearer. I'm open to suggestions.

Calling them the lower sequence is fine, but in that case I don't know what you meant by "a whole lot of the lower sequence has been somehow removed." If the lower sequence is the portion below the unconformity, none of it has been removed. I still have a feeling there may still be a terminology issue in play, either that or I'm missing something.

--Percy


This message is a reply to:
 Message 154 by edge, posted 01-03-2017 7:15 PM edge has responded

Replies to this message:
 Message 164 by edge, posted 01-03-2017 7:55 PM Percy has responded

    
Faith
Member
Posts: 25832
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 163 of 202 (796737)
01-03-2017 7:46 PM
Reply to: Message 151 by Percy
01-03-2017 2:55 PM


Percy writes:

What was it you imagined was eroded away when people described the surface of an angular unconformity as forming due to erosion of the higher portions of the tilted layers?

The uppermost portion of the tilted strata. Not a separate layering of strata.

Duh.


This message is a reply to:
 Message 151 by Percy, posted 01-03-2017 2:55 PM Percy has acknowledged this reply

    
edge
Member
Posts: 3904
From: Colorado, USA
Joined: 01-09-2002
Member Rating: 4.7


Message 164 of 202 (796739)
01-03-2017 7:55 PM
Reply to: Message 162 by Percy
01-03-2017 7:41 PM


Calling them the lower sequence is fine, but in that case I don't know what you meant by "a whole lot of the lower sequence has been somehow removed." If the lower sequence is the portion below the unconformity, none of it has been removed. I still have a feeling there may still be a terminology issue in play, either that or I'm missing something.

Certainly.

What I'm saying is that the portions of the fold that were above the current location of the unconformity (the red lines) are gone.

They had to go someplace, no?

Edited by edge, : No reason given.


This message is a reply to:
 Message 162 by Percy, posted 01-03-2017 7:41 PM Percy has responded

Replies to this message:
 Message 167 by Faith, posted 01-03-2017 8:01 PM edge has responded
 Message 169 by Percy, posted 01-03-2017 8:06 PM edge has not yet responded

  
Percy
Member
Posts: 15678
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.3


(1)
Message 165 of 202 (796740)
01-03-2017 7:59 PM
Reply to: Message 161 by Faith
01-03-2017 7:38 PM


Faith writes:

He's the one making the dogmatic claim that there were horizontal strata that eroded away, which is the idea I'm saying has never entered into this discussion before.

No, Faith, I never said anything like that, and until just now you never said that was your understanding of what I said. You might at least try keeping to a consistent story.

Summarizing the big problems with your fantasy scenario, cubic miles of strata cannot disappear without a trace (meaning no remains of rubble or signs of shearing), disturbances to buried strata cannot fail to disturb overlying strata, rocks weather to form the appearance of age according to their composition and length of exposure and not how long ago they formed, and sedimentary rocks do not form by drying.

--Percy


This message is a reply to:
 Message 161 by Faith, posted 01-03-2017 7:38 PM Faith has not yet responded

Replies to this message:
 Message 170 by edge, posted 01-03-2017 8:14 PM Percy has acknowledged this reply

    
RewPrev1
...
910
11
121314Next
Newer Topic | Older Topic
Jump to:


Copyright 2001-2015 by EvC Forum, All Rights Reserved

™ Version 4.0 Beta
Innovative software from Qwixotic © 2017