Understanding through Discussion


Welcome! You are not logged in. [ Login ]
EvC Forum active members: 85 (8950 total)
32 online now:
Aussie, DrJones*, Faith, Hyroglyphx, ringo, Tangle, Thugpreacha (AdminPhat) (7 members, 25 visitors)
Newest Member: Mikee
Post Volume: Total: 867,232 Year: 22,268/19,786 Month: 831/1,834 Week: 331/500 Day: 30/64 Hour: 5/10


Thread  Details

Email This Thread
Newer Topic | Older Topic
  
Author Topic:   Growing the Geologic Column
Coyote
Member (Idle past 449 days)
Posts: 6117
Joined: 01-12-2008


(1)
Message 256 of 740 (734300)
07-27-2014 8:50 PM
Reply to: Message 255 by JonF
07-27-2014 8:11 PM


There's a lesson to be learned from that if one were interested in learning.

My signature addresses that:

quote:
Belief gets in the way of learning.

And Faith is the poster child for that.

Edited by Adminnemooseus, : Off-topic banner.


Religious belief does not constitute scientific evidence, nor does it convey scientific knowledge.

Belief gets in the way of learning--Robert A. Heinlein

How can I possibly put a new idea into your heads, if I do not first remove your delusions?--Robert A. Heinlein

It's not what we don't know that hurts, it's what we know that ain't so--Will Rogers

If I am entitled to something, someone else is obliged to pay--Jerry Pournelle

If a religion's teachings are true, then it should have nothing to fear from science...--dwise1

"Multiculturalism" does not include the American culture. That is what it is against.


This message is a reply to:
 Message 255 by JonF, posted 07-27-2014 8:11 PM JonF has not yet responded

  
herebedragons
Member (Idle past 75 days)
Posts: 1513
From: Michigan
Joined: 11-22-2009


Message 257 of 740 (734302)
07-27-2014 9:41 PM
Reply to: Message 252 by edge
07-27-2014 5:57 PM


Re: Layer / Sill
Based on your and Moose's comments, I may have put the cart before the horse. It seems a basalt is a basalt because it is fine grained (plus the chemical composition part) not just because it is extrusive. However, it is fine grained because it cools rapidly which is indicative of an extrusion. That about right?

I do think Percy makes a good point that usage on the internet is not consistent and the term basalt is used for intrusions. I don't think I have seen the term gabbro used on a generalized cross section at all. So without more information, it is pretty difficult to be completely convincing that it is extrusive.

However, I don't see how tuffs or ash flows could be intrusions nor occur underwater, so they should be sufficient to establish a break in continuous sedimentation (during a flood).

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 252 by edge, posted 07-27-2014 5:57 PM edge has responded

Replies to this message:
 Message 263 by edge, posted 07-28-2014 1:16 AM herebedragons has not yet responded

  
Faith
Member
Posts: 33908
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.2


Message 258 of 740 (734303)
07-27-2014 11:07 PM
Reply to: Message 241 by edge
07-27-2014 5:07 PM


Cardenas basalt
I'm sorry, I don't see how that has anything to do with the question about the Cardenas basalt.

It shows ways of contrasting intrusive with extrusive igneous rocks. The Cardenas Basalt looks essentially like the diagram.

But what it shows is a dike up through the limestone, an intrusive event in other words, but you are saying the Cardenas is not an intrusive. In the example the lava spreads out on an exposed surface, which is similar, but it doesn't originate as an "extrusive."

And "extrusive" is a term that makes no sense to me in this connection. A lava can spread on the surface if it originates from an above-ground volcano, which is apparently what is being called extrusive, but if it originates deep underground, as it does beneath the Grand Canyon, then it is an intrusive as it pushes up through all the rock strata already present. Seems to me that basalt can be either depending on where it originates.

But back to the Cardenas. My expecting volcanism to have occurred after the strata was all laid down isn't some presupposition of mine, as you seem to be saying back upthread a ways, it is something I concluded, or let's say hypothesized, from looking at cross sections, especially of course the Grand Canyon cross section, where a magma dike is shown rising from basement rock through the Claron/Tertiary. The fault lines, the rising of the land, and the massive erosion all seem to have occurred in the same time frame.

Some of the magma beneath the canyon itself did not rise up through the strata but remained confined there -- diagrams show truncated intrusions. I connect it with the granite and the schist though you have some other explanation for that I haven't quite digested, and naturally also with that layer of Cardenas basalt -- but that basalt is also exposed to quite a depth on the surface of the canyon so it wasn't just confined though it seems to have originated beneath the canyon --yes, no?. Maybe I'm not picturing this quite right but if that magma/basalt formed both the layer in the Unkar group AND the basalt that's spilled over in the canyon itself, how do you picture it as surface in the Unkar group which then got layered over? Maybe I'm not asking this right. Since it's all over the place there, beneath the canyon and on the surface of the canyon, to me it makes sense that it would be a sill among those layers of the Unkar group. And I know you think I shouldn't be arguing with a geologist about such things.

Edited by Faith, : No reason given.


This message is a reply to:
 Message 241 by edge, posted 07-27-2014 5:07 PM edge has responded

Replies to this message:
 Message 265 by edge, posted 07-28-2014 1:29 AM Faith has not yet responded

  
Faith
Member
Posts: 33908
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.2


Message 259 of 740 (734304)
07-27-2014 11:26 PM
Reply to: Message 242 by Percy
07-27-2014 5:13 PM


New depositions strangely different from old strata
YES! Thanks for that much. It looks really strangely weirdly dramatically different. There is NO way there's ever going to be another Redwall limestone or Coconino sandstone. That's the way it just plain LOOKS when you compare those formations with the paltry depositions that are offered up as the equivalent today.

I don't know why HBD said such a thing. Buried geologic layers are made up of or include many of the same things we see on and near the surface today, such as lava basalt, volcanic ash, sand, silt, mud, clay, burrows, tracks, life (in the form of fossils), even things like entire oyster beds. To me the majority of geologic layers look like lithified ancestors of the layers forming today.

Well, all those things are natural to the Earth so they aren't going to stop, but the strata of what I've been calling the Geo Column just do look strangely different to me, as HBD put it, from what is going on today. And one thing that's different is the scale, those thick thick rocks that span whole continents, and originally piled three miles deep as well. That's why I said there will never be another Redwall Limestone or Coconino Sandstone, could add never another Dover Cliffs or that gigantic wall of rock somebody posted from South America a while back, sorry don't remember the name of it.


Yeah, Time, the Magic Ingredient that turns a delta or continental shelf into the Grand Canyon.

You make it sound like an ancient Earth is just something geologists made up, instead of something that is supported by literally mountains of evidence. The side in this debate who is making things up left and right is you.

Well, there's no point in arguing this out for the zillionth time but in a sense BOTH sides are making things up because that's pretty much all you can do with the prehistoric past. And when you are dealing with made-up stuff, just hypotheticals, it's really quite possible to construct a whole web of evidence for them that looks pretty convincing but is still only a web of interconnected ideas, assumptions, plausibilities and so on. It's easy to confirm something you can't really test. abe: the explanation for how the angular unconformity of Siccar Point formed is a case in point: it's all an argument from Reason, or plausibilities, abe: yes, of course based on observations of the rock itself, but still all you can do is INTERPRET what you're seeing, for the most part these things aren't testable. /abe There's no way to PROVE it formed the way Hutton said it did, you either find the arguments persuasive or you don't, and for all you know there are all sorts of facts that are no longer in evidence that would change your view of it, or just facts you overlook.

ABE: Looking for that picture of the South American formation, found "tepui" and Mt. Roraima which may be what I'm remembering but the picture that was posted here didn't show up. This one is maybe the closest:

Such enormous slabs of rock that originally had to have been strata suggest the Flood to my mind, and certainly not slow deposition over millions of years. But there's a case in point where it's a matter of finding an argument plausible or not. And besides such gigantic flat slabs of rock there are all kinds of strange/ weird/ bizarre geological formations all over the world that I can't see ever getting reproduced on the Old Earth model, that all suggest the Flood to me.

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 242 by Percy, posted 07-27-2014 5:13 PM Percy has responded

Replies to this message:
 Message 266 by edge, posted 07-28-2014 1:46 AM Faith has responded
 Message 369 by Percy, posted 07-29-2014 11:57 AM Faith has responded

  
Faith
Member
Posts: 33908
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.2


Message 260 of 740 (734305)
07-28-2014 12:52 AM
Reply to: Message 251 by Percy
07-27-2014 5:54 PM


Re: Layer / Sill
All that evidence for the Old Earth in all the sciences is mostly just plausibilities, interpretations of observations, suppositions, assumptions, hypotheses and so on. There's a lot of it so it looks like a lot of *evidence* -- which it is of course if you count plausibilities, interpretations of observations, assumptions, hypotheses and so on as evidence. Which again, is all anyone's got for the prehistoric past.

Walther's Law is about rising sea level, not waves, tsunami-sized or not. The Flood would certainly have been a case of rising sea level -- over a five month period or so, and then there was the regressive phase as well, another five month period or so. So your remark about time in relation to a tsunami is totally irrelevant. Not that huge waves couldn't have contributed to the Flood scenario, as I'm sure they must have occurred especially as most of the water had receded away. Tides would have been operating still after all.

YOu think it would have taken "geologic time" in the millions of years to lay down the sediments we see in the strata, I don't. Matter of plausibilities. You can't prove how long it would have taken and neither can I, but five months up and five months back seems like plenty of time to carry and dump sediments.

Edited by Faith, : No reason given.


This message is a reply to:
 Message 251 by Percy, posted 07-27-2014 5:54 PM Percy has responded

Replies to this message:
 Message 442 by Percy, posted 07-30-2014 2:42 PM Faith has responded

  
Faith
Member
Posts: 33908
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.2


Message 261 of 740 (734306)
07-28-2014 12:55 AM
Reply to: Message 253 by Percy
07-27-2014 6:06 PM


Re: Layer / Sill
Yeah, but I've never misused the terms dike or sill.

HBD put up that test that shows a dike which is NOT what edge was saying the Cardenas is.

This is all just a bunch of definitional hairsplitting about "basalt." Why waste time over such stuff? We're talking about lava from volcanoes, that has a variety of forms and contents and does different things. "Dike" and "sill" ought to be sufficient to describe it where it intrudes into rock.

Edited by Faith, : No reason given.

Edited by Faith, : No reason given.


This message is a reply to:
 Message 253 by Percy, posted 07-27-2014 6:06 PM Percy has acknowledged this reply

  
Faith
Member
Posts: 33908
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.2


Message 262 of 740 (734307)
07-28-2014 1:11 AM
Reply to: Message 216 by edge
07-27-2014 12:30 PM


Cardenas
Edited to add: I just noticed how this diagram shows the erosional unconformity between the Temple Butte and the Muav. Also, notice the presence of dikes and sills along with the Cardenas lava.

Erosional unconformity noted.

As for the dikes and sills, that just adds to the impression that the Cardenas could be a sill, just a particularly thick one.

Edited by Faith, : No reason given.


This message is a reply to:
 Message 216 by edge, posted 07-27-2014 12:30 PM edge has responded

Replies to this message:
 Message 267 by edge, posted 07-28-2014 1:49 AM Faith has responded

  
edge
Member (Idle past 49 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 263 of 740 (734308)
07-28-2014 1:16 AM
Reply to: Message 257 by herebedragons
07-27-2014 9:41 PM


Re: Layer / Sill
Based on your and Moose's comments, I may have put the cart before the horse. It seems a basalt is a basalt because it is fine grained (plus the chemical composition part) not just because it is extrusive. However, it is fine grained because it cools rapidly which is indicative of an extrusion. That about right?

Yes. The term 'basalt' has certiain implications, both textural and compositional.

I do think Percy makes a good point that usage on the internet is not consistent and the term basalt is used for intrusions. I don't think I have seen the term gabbro used on a generalized cross section at all. So without more information, it is pretty difficult to be completely convincing that it is extrusive.

It's all a function of cooling history. If a dike cools quickly, it could be a basalt. Usually this will happen at the surface or near the surface since that is where the cooler environments are.

However, I don't see how tuffs or ash flows could be intrusions nor occur underwater, so they should be sufficient to establish a break in continuous sedimentation (during a flood).

Correct. In general. Tuffs can be water lain if they occur over a lake, for instance. I have seen ash flows which probably covered a shallow lake or swamp. It gets really interesting...

This message is a reply to:
 Message 257 by herebedragons, posted 07-27-2014 9:41 PM herebedragons has not yet responded

  
Faith
Member
Posts: 33908
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.2


Message 264 of 740 (734309)
07-28-2014 1:21 AM


I've been slogging through the posts in this thread I hadn't answered yet and trying to respond at least where they raise questions or issues I want to address, or just where they interest me. But this is a LOT of work and I can't keep up with it. I've not responded to a lot of Percy's posts for instance, and HBD and JonF are both complaining I haven't dealt with posts of theirs. Earlier on and on earlier threads I just let a lot of long posts go, a lot of edge's for instance because he'd use technical terminology so that in many cases most of the post would simply be incomprehensible, as well as irritating for other reasons, and with so much coming at me I'm not going to stop and look up all those terms. I'm glad he seems to have stopped doing that. In any case, I can't do better than I'm doing, don't know what the solution to this is if there is any.

Replies to this message:
 Message 268 by Pressie, posted 07-28-2014 1:52 AM Faith has not yet responded

  
edge
Member (Idle past 49 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


(1)
Message 265 of 740 (734310)
07-28-2014 1:29 AM
Reply to: Message 258 by Faith
07-27-2014 11:07 PM


Re: Cardenas basalt
But what it shows is a dike up through the limestone, an intrusive event in other words, but you are saying the Cardenas is not an intrusive.

Maybe I can clarify. The lava flows are definitely extrusive onto the surface of the earth. The thing is that they have to come from somewhere. We often call those sources 'feeders' or vents. Those would be very close to the surface, yet intrusive.

Edited to add: I'm still not sure that this is clear. Is it understood that there is a transition between intrusive and extrusive? In other words, some volcanic rocks can be considered to be intrusive. Sometimes we call the in-between rocks 'sub-volcanic'. Does this help?

In the example the lava spreads out on an exposed surface, which is similar, but it doesn't originate as an "extrusive."

If there is one thing that people should know about geology is that things are usually more complex than one would like. Yes, volcanic rocks must have some intrusive source. It may be miles away, but it surely exists.

And "extrusive" is a term that makes no sense to me in this connection. A lava can spread on the surface if it originates from an above-ground volcano, which is apparently what is being called extrusive, but if it originates deep underground, as it does beneath the Grand Canyon, then it is an intrusive as it pushes up through all the rock strata already present. Seems to me that basalt can be either depending on where it originates.

Yes. But when we think of the Siberian Traps, or the Columbia River Basalts, or the Deccan Traps ("traps" is great word, eh?) we think of the extrusive rocks. Their ventssource is implied.

But back to the Cardenas. My expecting volcanism to have occurred after the strata was all laid down isn't some presupposition of mine, as you seem to be saying back upthread a ways, it is something I concluded, or let's say hypothesized, from looking at cross sections, especially of course the Grand Canyon cross section, where a magma dike is shown rising from basement rock through the Claron/Tertiary. The fault lines, the rising of the land, and the massive erosion all seem to have occurred in the same time frame.

The fairly obvisou conclusion is that there are multiple volcanic events...

Some of the magma beneath the canyon itself did not rise up through the strata but remained confined there -- diagrams show truncated intrusions. I connect it with the granite and the schist though you have some other explanation for that I haven't quite digested, and naturally also with that layer of Cardenas basalt -- but that basalt is also exposed to quite a depth on the surface of the canyon so it wasn't just confined though it seems to have originated beneath the canyon --yes, no?

Well, all intrusive rocks and extrusive rocks had a source somewhere beneath.

Maybe I'm not picturing this quite right but if that magma/basalt formed both the layer in the Unkar group AND the basalt that's spilled over in the canyon itself, how do you picture it as surface in the Unkar group which then got layered over?

As I said, they are different events, though you deny it. Detailed chemistry and age dates will confirm this.

Maybe I'm not asking this right. Since it's all over the place there, beneath the canyon and on the surface of the canyon, to me it makes sense that it would be a sill among those layers of the Unkar group. And I know you think I shouldn't be arguing with a geologist about such things.

No one knows everything. You can question all you want. You can argue all you want. It'a free world, at least here.

Edited by edge, : No reason given.


This message is a reply to:
 Message 258 by Faith, posted 07-27-2014 11:07 PM Faith has not yet responded

  
edge
Member (Idle past 49 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


(1)
Message 266 of 740 (734312)
07-28-2014 1:46 AM
Reply to: Message 259 by Faith
07-27-2014 11:26 PM


Re: New depositions strangely different from old strata
Well, there's no point in arguing this out for the zillionth time but in a sense BOTH sides are making things up because that's pretty much all you can do with the prehistoric past.

Except that some of us can provide evidence.

And when you are dealing with made-up stuff, just hypotheticals, it's really quite possible to construct a whole web of evidence for them that looks pretty convincing but is still only a web of interconnected ideas, assumptions, plausibilities and so on. It's easy to confirm something you can't really test.

We test things all the time. I"m not sure what you are talking about here.

abe: the explanation for how the angular unconformity of Siccar Point formed is a case in point: it's all an argument from Reason, or plausibilities, abe: yes, of course based on observations of the rock itself, but still all you can do is INTERPRET what you're seeing, for the most part these things aren't testable.

Well then, show us the countervailing evidence, or prove the logic to be incorrect. Simply making assertions is schoolyard stuff.

There's no way to PROVE it formed the way Hutton said it did,

"Proof" is for mathematics and alcohol. Which one are you talking about?

... you either find the arguments persuasive or you don't, and for all you know there are all sorts of facts that are no longer in evidence that would change your view of it, or just facts you overlook.

Then you have your work cut out for you. The current evidence suggests an old earth. If you have other evidence, it's time to bring it on.

ABE: Looking for that picture of the South American formation, found "tepui" and Mt. Roraima which may be what I'm remembering but the picture that was posted here didn't show up. This one is maybe the closest:

Yes, I've been there. It's not really a mystery. it is an uplifted plateau that is being eroded away and leaving behind individual monuments or tepui.

Such enormous slabs of rock that originally had to have been strata suggest the Flood to my mind, and certainly not slow deposition over millions of years. But there's a case in point where it's a matter of finding an argument plausible or not. And besides such gigantic flat slabs of rock there are all kinds of strange/ weird/ bizarre geological formations all over the world that I can't see ever getting reproduced on the Old Earth model, that all suggest the Flood to me.

The weird thing is that these rocks are Precambrian. In other words, an entire sequence of rocks that you refuse to seriously discuss in the Grand Canyon.

And actually, the fact that they are so old is an argument that that, indeed, similar formations may not be forming now.


This message is a reply to:
 Message 259 by Faith, posted 07-27-2014 11:26 PM Faith has responded

Replies to this message:
 Message 272 by Faith, posted 07-28-2014 2:25 AM edge has responded

  
edge
Member (Idle past 49 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 267 of 740 (734313)
07-28-2014 1:49 AM
Reply to: Message 262 by Faith
07-28-2014 1:11 AM


Re: Cardenas
As for the dikes and sills, that just adds to the impression that the Cardenas could be a sill, just a particularly thick one.

Why is that? You have been given abundant evidence that the Cardenas is extrusive. Why do you simply deny?

Why do you assume that there is only one intrusive/extrusive event?


This message is a reply to:
 Message 262 by Faith, posted 07-28-2014 1:11 AM Faith has responded

Replies to this message:
 Message 270 by Faith, posted 07-28-2014 2:11 AM edge has responded

  
Pressie
Member
Posts: 2082
From: Pretoria, SA
Joined: 06-18-2010


(1)
Message 268 of 740 (734314)
07-28-2014 1:52 AM
Reply to: Message 264 by Faith
07-28-2014 1:21 AM


Faith writes:

But this is a LOT of work and I can't keep up with it.


Of course it is. You do know that tens of thousands of geologists all over the world get paid for doing geology full-time? In my country around 3 000; where exploration and mining companies are the biggest employers, followed by research organisations (exploration and mining companies provide most of the funds for research on geology), Universities (exploration and mining companies provide most of the funds for research on geology) , Government research organisations (exploration and mining companies provide most of the funds for research on geology), etc.? Every single person working full-time on geology knows more than you about the subject.

This message is a reply to:
 Message 264 by Faith, posted 07-28-2014 1:21 AM Faith has not yet responded

Replies to this message:
 Message 269 by edge, posted 07-28-2014 2:00 AM Pressie has responded

  
edge
Member (Idle past 49 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


(1)
Message 269 of 740 (734315)
07-28-2014 2:00 AM
Reply to: Message 268 by Pressie
07-28-2014 1:52 AM


Of course it is. You do know that tens of thousands of geologists all over the world get paid for doing geology full-time? In my country around 3 000; where exploration and mining companies are the biggest employers, followed by research organisations (exploration and mining companies provide most of the funds for research on geology), Universities (exploration and mining companies provide most of the funds for research on geology) , Government research organisations (exploration and mining companies provide most of the funds for research on geology), etc.? Every single person working full-time on geology knows more than you about the subject.

Good points, and you know what?

They test geological theories every day.


This message is a reply to:
 Message 268 by Pressie, posted 07-28-2014 1:52 AM Pressie has responded

Replies to this message:
 Message 271 by Faith, posted 07-28-2014 2:13 AM edge has not yet responded
 Message 278 by Pressie, posted 07-28-2014 3:05 AM edge has not yet responded

  
Faith
Member
Posts: 33908
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.2


Message 270 of 740 (734316)
07-28-2014 2:11 AM
Reply to: Message 267 by edge
07-28-2014 1:49 AM


Re: Cardenas

As for the dikes and sills, that just adds to the impression that the Cardenas could be a sill, just a particularly thick one.

Why is that?

I don't see why not. There are already sills there, why not another?

You have been given abundant evidence that the Cardenas is extrusive. Why do you simply deny?
Why do you assume that there is only one intrusive/extrusive event?

I'm not so much assuming it as looking for evidence for it. Because I did get convinced that all this occurred after the strata were laid down so I continue to look for how that could be evidenced. I'm sure it's frustrating to you since you've got it all worked out to your own satisfaction already, but I'm still looking for new angles on it. You've given some evidence but it doesn't strike me as conclusive: the erosional surfaces.


This message is a reply to:
 Message 267 by edge, posted 07-28-2014 1:49 AM edge has responded

Replies to this message:
 Message 277 by edge, posted 07-28-2014 3:05 AM Faith has responded
 Message 443 by Percy, posted 07-30-2014 3:01 PM Faith has responded

  
Newer Topic | Older Topic
Jump to:


Copyright 2001-2018 by EvC Forum, All Rights Reserved

™ Version 4.0 Beta
Innovative software from Qwixotic © 2019