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Author Topic:   Continuation of Flood Discussion
Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 301 of 1304 (731559)
05-15-2014 3:05 PM


Re: the great unconformity
Faith writes:
Things that are made up are sometimes called theories.
In science, "things that are made up" are never called theories. If you hate science so much, why are you trying to be scientific?
I don't see much in that article about the source of the various kinds of rocks and minerals in the GC basement rocks.
Well, now you're just being goofy. The article is full of information about " the source of the various kinds of rocks and minerals in the GC basement rocks." In this excerpt I've highlighted the sections that are specific about origin:
Wikipedia writes:
The Granite Gorge Metamorphic Suite consists of lithologic units, the Brahma, Rama, and Vishnu schists, that have been mapped within the Upper, Middle, and Lower Granite Gorges of the Grand Canyon. The Vishnu Schist consists of quartz-mica schist, pelitic schist, and meta-arenites. They exhibit relict sedimentary structures and textures that demonstrate that they are metamorphosed submarine sedimentary rocks. The Brahma Schist consists of amphibolite, hornblende-biotite-plagioclase schist, biotite-plagioclase schist, orthoamphibole-bearing schist and gneiss, and metamorphosed sulfide deposits. As inferred from relict structures and textures, the Brahma Schist is composed of mafic to felsic-composition metavolcanic rocks. The Rama Schist consists of massive, fine-grained quartzofeldspathic schist and gneiss that likely are probable felsic metavolcanic rocks. On the basis of the presence of relict pillow structures, interlayering of metavolcanic strata, and the large volumes of metavolcanic rocks, the Brahma and Rama schists are interpreted to consist of metamorphosed, volcanic island-arc and associated submarine volcanic rocks. These metavolcanic rocks are locally overlain by the metamorphosed submarine sedimentary rocks of the Vishnu Schist that are interpreted to have accumulated in oceanic trenches. These metasedimentary rocks were originally composed of particles of quartz, clay, and volcanic rock fragments that have become metamorphosed into various schists. The Vishnu Schist exhibits relict graded bedding and structures indicative of turbidite deposits that accumulated in oceanic trenches and other relatively deep-marine settings. The Brahma Schist has been dated to about 1.75 Ga, (1,750 Mya). The felsic metavolcanic rocks that comprise the Rama Schist have yielded an age of 1.742 Ga.
Of course, as inconsistent as ever, you go on to reveal that you *did* find information about origin:
A lot of it is igneous which is to be expected, but there are rocks with a sedimentary origin too.
Do you see anything in there about sandstone or limestone origins, which form a significant portion of the supergroup layers?
I wouldn't give up on the idea too soon myself.
We're well aware that evidence has nothing to do with how seriously you consider an idea. If you think an idea has Biblical support then you'll never give up on it. Whether it has evidence or not is irrelevant to you.
--Percy

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


Message 302 of 1304 (731560)
05-15-2014 3:28 PM


Re: the great unconformity
I meant origin in the sense of original deposition or location. They mention that the Vishnu was uplifted about ten miles for instance.
You highlighted the interpretive part. I would highlight the kinds of rocks found there:
The Vishnu Schist consists of quartz-mica schist, pelitic schist, and meta-arenites. They exhibit relict sedimentary structures and textures that demonstrate that they are metamorphosed submarine sedimentary rocks.

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


Message 303 of 1304 (731561)
05-15-2014 3:30 PM


Re: the great unconformity
All edge does is obfuscate and pull rank, he does nothing else. He's a bully and a shyster.

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


Message 304 of 1304 (731562)
05-15-2014 3:37 PM


Re: the great unconformity
I meant origin in the sense of original deposition or location. They mention that the Vishnu was uplifted about ten miles for instance.
You do realize, of course, that there are a number of marine sedimentary environments, right?
Okay, so the GC Supergroup has limestone in it, so where do we see limestone or metamorphosed limestone in the Vishnu?
On the other hand, we do see rounded Vishnu pebbles in the GC Supergroup. That would mean that the Vishnu is older...
Weird, eh?
The Vishnu Schist consists of quartz-mica schist, pelitic schist, and meta-arenites. They exhibit relict sedimentary structures and textures that demonstrate that they are metamorphosed submarine sedimentary rocks.
Hmm, okay pelites... where do they occur in the GC Supergroup?
ETA: Oh, yeah, and the volcanic rocks, too...
Edited by edge, : No reason given.

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


Message 305 of 1304 (731563)
05-15-2014 3:39 PM


Re: the great unconformity
All edge does is obfuscate and pull rank, he does nothing else. He's a bully and a shyster.
Strange how it's only you who has such problem understanding my posts, isn't it? Just remember, there is a reason that you are frustrated and it can be fixed with some reading and some learning about geology.

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


Message 306 of 1304 (731564)
05-15-2014 3:49 PM


Re: the great unconformity
I just spent more than an hour earlier reading up on the Vishnu schist and related linked topics. I've spent hours and hours and hours reading up on geology over the years.
I have NO interest in talking to someone whose only interest is in pulling rank and oneupsmanship. This is not a debate, this is just an arena for bullying.

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


Message 307 of 1304 (731565)
05-15-2014 3:59 PM


Re: the great unconformity
I just spent more than an hour earlier reading up on the Vishnu schist and related linked topics. I've spent hours and hours and hours reading up on geology over the years.
And?
I have NO interest in talking to someone whose only interest is in pulling rank and oneupsmanship. This is not a debate, this is just an arena for bullying.
I don't remember saying any such thing. If you don't want to learn any facts contrary to your opinions, there isn't much that I can help you with.

  
Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 308 of 1304 (731566)
05-15-2014 4:08 PM


Re: the great unconformity
Faith writes:
You highlighted the interpretive part. I would highlight the kinds of rocks found there:
The Vishnu Schist consists of quartz-mica schist, pelitic schist, and meta-arenites. They exhibit relict sedimentary structures and textures that demonstrate that they are metamorphosed submarine sedimentary rocks.
I highlighted the exact same text, just a shorter portion of it, the part that explicitly describes the "original deposition" material (to use your words), which is what you said was missing. Are you not able to understand the meaning of this passage you just quoted? Do you not see that it is saying that Vishnu Schist is composed of metamorphosed rock that was originally sedimentary layers from a marine environment?
--Percy

  
Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 309 of 1304 (731567)
05-15-2014 4:10 PM


Re: the great unconformity
Faith writes:
All edge does is obfuscate and pull rank, he does nothing else. He's a bully and a shyster.
Would everyone who sees Edge's contributions in this thread as nothing but incredibly patient and informative please give his Message 305 an upvote.
--Percy

  
Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 310 of 1304 (731568)
05-15-2014 8:04 PM


Re: the great unconformity
Faith writes:
At any angular unconformity Geology says there is a zone of erosion between the upper and lower sections,...
Yes.
...which you appear to be denying based on the photographs you posted of the Great Unconformity.
No.
When a surface is eroded, the eroded material is absent. It's no longer there, carried away by wind and water. The next sedimentary layer is deposited directly onto the eroded surface.
But in your scenario the top of the Great Unconformity is not an eroded surface. For you it's an interface with the Tapeats where somehow the deeply buried supergroup layers tilted, and all that material of the supergroup layers had to go somewhere, and what you said in Message 271 was:
Faith in Message 271 writes:
The block of strata broke off as it was pushed up against the Tapeats, and the erosion caused by the abrasion between it and the Tapeats collected along the contact line as it slid for some distance, but also collected beneath the block itself...The rest of the length of the strata from which the tilted block broke off has to be where it always was, it's just not shown on the diagrams.
And so I responded with images showing that there is no layer of broken material between the tilted supergroup and the Tapeats. Strangely, you looked at the images and seem to believe there *is* broken material between the supergroup and the Tapeats, but there isn't. You must be looking at the scree. Eroded material from above gathers on any available surface. We've been over this before.
--Percy

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


Message 311 of 1304 (731569)
05-15-2014 10:38 PM


Re: the great unconformity
I find it curious (for lack of a better term) that the Tapeats appears to be (and is) angularly unconformable in the left 2/3rds of the photo, but appears to be conformable in the right 1/3rd of the photo. It must be that the lower units must be striking* parallel to the unconformity exposure in the right 1/3rd.
Which goes to show you, that a wrong perspective can give you a very wrong image of what is there.
Moose
* Strike - The bearing (compass direction) of a horizontal line on a bedding plane, a fault plane, or some other planar structural feature.

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


Message 312 of 1304 (731570)
05-15-2014 10:52 PM


Re: the great unconformity
I find it curious (for lack of a better term) that the Tapeats appears to be (and is) angularly unconformable in the left 2/3rds of the photo, but appears to be conformable in the right 1/3rd of the photo. It must be that the lower units must be striking* parallel to the unconformity exposure in the right 1/3rd.
Which goes to show you, that a wrong perspective can give you a very wrong image of what is there.
Moose
* Strike - The bearing (compass direction) of a horizontal line on a bedding plane, a fault plane, or some other planar structural feature.
It's a case of apparent dip.
https://www.google.com/#q=apparent+dip
Edited by edge, : No reason given.
Edited by edge, : No reason given.

  
JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


Message 313 of 1304 (731571)
05-16-2014 8:30 AM


Re: the great unconformity
I've spent hours and hours and hours reading up on geology over the years.
Obviously untrue. If you really had you would know the lingo and know something of mainstream geology. You know neither.
Perhaps you meant to say you have spent hours gazing uncomprehendingly at geology books and we sites?

  
Percy
Member
Posts: 22391
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 314 of 1304 (731572)
05-16-2014 8:33 AM


Re: the great unconformity
This image is a good illustration of how the direction of cut through tilted layers affects their appearance:
A cut parallel to the tilt, the left face of the cube, shows all of the tilt. A cut at a 45 degree angle to the tilt, the middle plane at the top, shows only some of the tilt. And a cut perpendicular to the tilt, the right face of the cube, shows no tilt at all.
--Percy

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


Message 315 of 1304 (731573)
05-16-2014 9:09 AM


Re: the great unconformity
When a surface is eroded, the eroded material is absent. It's no longer there, carried away by wind and water. The next sedimentary layer is deposited directly onto the eroded surface.
It's really kind of amusing when I make an assertion based on what I've learned from a Geology source that some EvCer will come along and contradict it thinking I made it up.
Here's a video about the Great Unconformity where the erosion is pointed out about halfway through, starting about 2:40:
Perhaps I should go find that video of Paul Garner the UK creationist that has lots of good footage of the Grand Canyon and clearly shows the band of erosion between the Great Unconformity and the Tapeats.

  
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