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Author Topic:   Growing the Geologic Column
edge
Member (Idle past 49 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 241 of 740 (734283)
07-27-2014 5:07 PM
Reply to: Message 239 by Faith
07-27-2014 5:04 PM


Re: Blackrock Escarpment is all volcanic
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.

Edited by edge, : No reason given.


This message is a reply to:
 Message 239 by Faith, posted 07-27-2014 5:04 PM Faith has responded

Replies to this message:
 Message 258 by Faith, posted 07-27-2014 11:07 PM edge has responded

  
Percy
Member
Posts: 19110
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.0


(1)
Message 242 of 740 (734284)
07-27-2014 5:13 PM
Reply to: Message 237 by Faith
07-27-2014 4:54 PM


Re: Layer / Sill
Faith writes:

In her defense, I think that what we observe happening today DOES look strangely different than what we see in the rock record.

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.

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.

--Percy


This message is a reply to:
 Message 237 by Faith, posted 07-27-2014 4:54 PM Faith has responded

Replies to this message:
 Message 246 by herebedragons, posted 07-27-2014 5:31 PM Percy has acknowledged this reply
 Message 259 by Faith, posted 07-27-2014 11:26 PM Percy has responded

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


Message 243 of 740 (734285)
07-27-2014 5:16 PM
Reply to: Message 239 by Faith
07-27-2014 5:04 PM


Re: Blackrock Escarpment is all volcanic
Oh come on!

The way to tell the difference between a sill and a subaerial flow is by contact metamorphosis surfaces. In the problem presented, is there contact metamorphosis in the contact between the lava flow and the shale above it? NO. So the shale was not there when the lava extruded and it was NOT an intrusion into the shale layer.

If you want to know if the Cardenas lava is intrusive or extrusive, look at the contact metamorphosis between it and the layer that overlies 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 239 by Faith, posted 07-27-2014 5:04 PM Faith has not yet responded

  
Faith
Member
Posts: 33907
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.2


Message 244 of 740 (734286)
07-27-2014 5:16 PM
Reply to: Message 217 by edge
07-27-2014 12:46 PM


Re: Layer / Sill
In her defense, I think that what we observe happening today DOES look strangely different than what we see in the rock record. But to me it highlights the fact that it takes lots of time (as well as specific circumstances) to convert these unconsolidated sediments into recognizable rock units. We just don't see it happening year by year as it would have had to happen in a global flood.

In order for Walther's Law to be in effect, you must have changing sea levels and this only really happens on a scale of geological time.

According to Old Earth assumptions, but they are just assumptions, something you take for granted, but if a worldwide Flood DID occur that would provide the very situation of changing sea levels where Walther's Law operates, but much faster. In the case of the Flood it took about five months for the level to rise to its fullest height and after it had stayed at its height for a month or two it took another five months to regress. Plenty of time to deposit all those sediments the forty days and nights of heavy rain had dumped into the rising water.

If the Atlantic Ocean transgressed across New Jersey and into the mid-west, you'd see layers precursive to those Faith is talking about.

Yes, that's the idea. And so much the more if the Pacific wandered up to meet the Atlantic in the Midwest.


This message is a reply to:
 Message 217 by edge, posted 07-27-2014 12:46 PM edge has responded

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Percy
Member
Posts: 19110
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.0


Message 245 of 740 (734287)
07-27-2014 5:22 PM
Reply to: Message 240 by herebedragons
07-27-2014 5:05 PM


Re: Layer / Sill
herebedragons writes:

When a rock is referred to as Basalt, it can be assumed to be extrusive, unless there are reasons to think otherwise. Are there reasons why you think those examples are intrusions?

You're right, but if you do a Google search for "intrusive basalt" (including the quotes) you'll get thousands of results. During the discussion while poking around on the web it seemed to me like there are many articles out there that aren't careful in their terminology and refer to sills and dikes as just "basalt" without the "intrusive" modifier.

So I wonder if it might be better to not belabor the point about correct usage of the word "basalt" and instead just always be clear about whether we're talking about extrusive or intrusive, or about lava or magma, or about sills or lava layers.

--Percy


This message is a reply to:
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Replies to this message:
 Message 249 by herebedragons, posted 07-27-2014 5:43 PM Percy has acknowledged this reply
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herebedragons
Member (Idle past 75 days)
Posts: 1513
From: Michigan
Joined: 11-22-2009


Message 246 of 740 (734289)
07-27-2014 5:31 PM
Reply to: Message 242 by Percy
07-27-2014 5:13 PM


Re: Layer / Sill
I don't know why HBD said such a thing.

I guess its just that to someone who doesn't study these things a lot, it can be hard to see the kind of processes that will someday, maybe, become rock. Its like looking at a still of a movie and trying to figure out the plot. I too see the same processes at work today that formed the features of the past. However, I can see how someone like Faith would see it as strangely different. It does take some research to understand 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 242 by Percy, posted 07-27-2014 5:13 PM Percy has acknowledged this reply

Replies to this message:
 Message 248 by edge, posted 07-27-2014 5:36 PM herebedragons has not yet responded

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


(1)
Message 247 of 740 (734290)
07-27-2014 5:31 PM
Reply to: Message 244 by Faith
07-27-2014 5:16 PM


Re: Layer / Sill
According to Old Earth assumptions, ...

I have yet to be shown that the supported assumption of an old earth is wrong. Perhaps you can do that?

... but they are just assumptions, ...

Well-supported assumptions.

... something you take for granted, ...

Not at all. I agree that some processes are rapid.

... but if a worldwide Flood DID occur that would provide the very situation of changing sea levels where Walther's Law operates, but much faster.

Actually, the law would be in effect, but there would be vanishingly little time to produce a record.

In the case of the Flood it took about five months for the level to rise to its fullest height and after it had stayed at its height for a month or two it took another five months to regress.

Not enough time to create the deposits that we find. Where did the sediments come from? How did dinosaur tracks form in the middle of the fludde? Where did evaporites come from?

Why are these questions radioactive to YECs?

Plenty of time to deposit all those sediments the forty days and nights of heavy rain had dumped into the rising water.

Please show what rocks eroded to provide the sediments in 40 days.

Yes, that's the idea. And so much the more if the Pacific wandered up to meet the Atlantic in the Midwest.

If, if, if...

Please provide evidence of such a fludde.


This message is a reply to:
 Message 244 by Faith, posted 07-27-2014 5:16 PM Faith has not yet responded

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


Message 248 of 740 (734291)
07-27-2014 5:36 PM
Reply to: Message 246 by herebedragons
07-27-2014 5:31 PM


Re: Layer / Sill
I guess its just that to someone who doesn't study these things a lot, it can be hard to see the kind of processes that will someday, maybe, become rock. Its like looking at a still of a movie and trying to figure out the plot. I too see the same processes at work today that formed the features of the past. However, I can see how someone like Faith would see it as strangely different. It does take some research to understand it.

It's hard sometime to wrap your mind around geological concepts. To me, a Mesozoic rock looks different from a Paleozoic rock, different from a Proterozoic rock. I can imagine someone trying to figure out how a modern stream channel gets incorporated into the geological record; keeping mind that all we really are familiar with is terrestrial processes. I think if you see a lot of rocks with similar depositional environments from various ages, it becomes easier.

This message is a reply to:
 Message 246 by herebedragons, posted 07-27-2014 5:31 PM herebedragons has not yet responded

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


Message 249 of 740 (734292)
07-27-2014 5:43 PM
Reply to: Message 245 by Percy
07-27-2014 5:22 PM


Re: Layer / Sill
So I wonder if it might be better to not belabor the point about correct usage of the word "basalt" and instead just always be clear about whether we're talking about extrusive or intrusive, or about lava or magma, or about sills or lava layers.

You're probably right, but most stratigraphic sections I have found only identify them as "basalt" which Faith simply dismisses as intrusive. Just like I presented 4 sections with clear lava layers between sedimentary layers and what I get is "basalt IS usually intrusive into sedimentary rock,"

Grrrr.

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 245 by Percy, posted 07-27-2014 5:22 PM Percy has acknowledged this reply

Replies to this message:
 Message 252 by edge, posted 07-27-2014 5:57 PM herebedragons has responded

  
Minnemooseus
Member
Posts: 3781
From: Duluth, Minnesota, U.S. (West end of Lake Superior)
Joined: 11-11-2001
Member Rating: 5.2


(1)
Message 250 of 740 (734294)
07-27-2014 5:52 PM
Reply to: Message 245 by Percy
07-27-2014 5:22 PM


Re: Layer / Sill
I'm reading a fair amount of "Yes, but.." material from the evo side.

Basalt, diabase (also called dolerite), and gabbro all have the same (general) chemical composition. I say "general", in that there is a considerable amount of variation.

The difference is grain size, fine to coarse for the above. And yes, there are dikes and sills that are considered to be basalts (or basaltic).

Shallow and/or small intrusives can be quite fine grained. On point about intrusives that didn't seem to be covered very well, is that they would tend to have chilled margins. In other words, the margins cooled faster and are finer grained, and the interiors cooled slower and are coarser grained.

...here are many articles out there that aren't careful in their terminology and refer to sills and dikes as just "basalt" without the "intrusive" modifier.

That they are sills or dikes automatically means "intrusive". Intrusive dike would be a redundancy.

Gotta go.

Moose


This message is a reply to:
 Message 245 by Percy, posted 07-27-2014 5:22 PM Percy has responded

Replies to this message:
 Message 253 by Percy, posted 07-27-2014 6:06 PM Minnemooseus has acknowledged this reply
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Percy
Member
Posts: 19110
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.0


(1)
Message 251 of 740 (734295)
07-27-2014 5:54 PM
Reply to: Message 244 by Faith
07-27-2014 5:16 PM


Re: Layer / Sill
Faith writes:

According to Old Earth assumptions, but they are just assumptions, something you take for granted,...

There are no assumptions. The amount of evidence for an ancient Earth is massive across many fields of science, not just geology. You're just tossing grenades into the discussion. Let's keep the focus on the topic.

...but if a worldwide Flood DID occur that would provide the very situation of changing sea levels where Walther's Law operates, but much faster.

The tsunami wave that flowed over Japan did not leave behind anything resembling Walther's Law. That's because Walther's Law requires geologic time in order to operate. Waves have to pound shorelines day after day and year after year for eons while runoff from land feeds the process as a source of the sedimentary material laid down by Walther's Law. A flood, no matter how large, cannot leave behind this kind of sedimentary sequence nor even these kinds of sedimentary layers to any significant extent.

If the Atlantic Ocean transgressed across New Jersey and into the mid-west, you'd see layers precursive to those Faith is talking about.

Yes, that's the idea. And so much the more if the Pacific wandered up to meet the Atlantic in the Midwest.

If Edge was describing a situation where in just a few months the Atlantic Ocean transgressed all the way to the mid-west, then no, we wouldn't observe anything like the flood layers you keep describing, not even precursors.

If Edge was instead describing a situation where in geologic time the Atlantic Ocean transgressed all the way to the mid-west, then yes, we would observe the beginnings of the types of layers normally seen in the geologic record.

--Percy


This message is a reply to:
 Message 244 by Faith, posted 07-27-2014 5:16 PM Faith has responded

Replies to this message:
 Message 260 by Faith, posted 07-28-2014 12:52 AM Percy has responded

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


Message 252 of 740 (734296)
07-27-2014 5:57 PM
Reply to: Message 249 by herebedragons
07-27-2014 5:43 PM


Re: Layer / Sill
You're probably right, but most stratigraphic sections I have found only identify them as "basalt" which Faith simply dismisses as intrusive. Just like I presented 4 sections with clear lava layers between sedimentary layers and what I get is "basalt IS usually intrusive into sedimentary rock,"

I would say that the term 'basalt' generally refers to an extrusive igneous rock, unless qualified or otherwise determined by context.

A coarse-grained basaltic (composition) rock would be called a gabbro, so many dikes are actually gabbro. These are almost certainly intrusive in character. I know of no extrusive gabbros, or granites.

In a way it is unfortunate that geology is such an old science that there are many archaic terms, and casually used words, along with words derived from a variety of languages just to confuse things. However, it makes for a rich history and colorful language, just takes a long time to master it.

ETA: I should add that 'basalt' definitely refers to a fine-grained rock.

Grrrr.

Being casually dismissed is a sure insult.

Edited by edge, : No reason given.


This message is a reply to:
 Message 249 by herebedragons, posted 07-27-2014 5:43 PM herebedragons has responded

Replies to this message:
 Message 257 by herebedragons, posted 07-27-2014 9:41 PM edge has responded

  
Percy
Member
Posts: 19110
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.0


Message 253 of 740 (734297)
07-27-2014 6:06 PM
Reply to: Message 250 by Minnemooseus
07-27-2014 5:52 PM


Re: Layer / Sill
Minnemooseus writes:

That they are sills or dikes automatically means "intrusive". Intrusive dike would be a redundancy.

Well, sure, but misuses like that are what you find on the Internet, and the Internet is where Faith finds most of the raw material from which she constructs her misimpressions. The first result of a Google search for "intrusive basalt" is a website with the phrase "intrusive basalt dike".

But my main concern is when "basalt" is used without a modifier. We could insist that it always means extrusive, but we'd be fighting Faith forever on that definition because half the Internet uses it to also refer to sills, plugs and dikes.

--Percy


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 Message 250 by Minnemooseus, posted 07-27-2014 5:52 PM Minnemooseus has acknowledged this reply

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


Message 254 of 740 (734298)
07-27-2014 6:12 PM
Reply to: Message 250 by Minnemooseus
07-27-2014 5:52 PM


Re: Layer / Sill
I'm reading a fair amount of "Yes, but.." material from the evo side.

I think this comes from trying to provide a textbook in piecemeal fashion. And most of the discrepancies are really not relevant to the actual discussion being driven by Faith's strange understanding of geological evidence.

This message is a reply to:
 Message 250 by Minnemooseus, posted 07-27-2014 5:52 PM Minnemooseus has acknowledged this reply

  
JonF
Member
Posts: 5626
Joined: 06-23-2003
Member Rating: 2.6


Message 255 of 740 (734299)
07-27-2014 8:11 PM
Reply to: Message 234 by Faith
07-27-2014 4:47 PM


To me this is unique.

Obviously. But it is far from unique on Earth. And yet you have claimed that all sedimentary layers were in place before these igneous layers formed.

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

Edited by Admin, : Fix typo.


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