Exploring the Grand Canyon, from the bottom up.

Unfortunately, I won't have time to get to your comments today as I will be in a class all day today, but I think they are good ones.Your comments illustrate the different mindset that exists between what Creationists and some laity consider 'testable science' and what scientists consider testable science.One thing that popped out at me immediately is your implication that I present everything I have stated (in the interpretive portions of my posts) as 100% correct or absolute fact. That is simply not true. Everything I've stated beyond the facts is interpretive AND tentative AND subject to change. Some of it is a bit conjectural, but it all is based on the factual observation.I can explain why graded bedding or pillow structures are significant observations in metamorphic rocks, while you haven't yet been able to adequately support your positions or arguments with any definitive evidence whatsoever.This message has been edited by AdminAsgara, 03-15-2006 08:49 AM

There's really nothing to discuss.All I care about is getting across the distinction between the actual facts and the conjecture. Sometimes the conjectures are offered a little more tentatively than at other times, and sometimes some of the evidence that leads to them is offered too -- more so when the discussion is among scientists I gather, but what the layperson is usually confronted with is nothing but the imaginative scenario. Stick to the actual facts and there is no problem.In fact the exact conditions of the rocks that lead to such conjectures as "marine environment" are often left out or blurred over. I'd simply appreciate it if you and the other geologists would be alert to this effect and try to fill in the descriptive material that supposedly explains the scenarios -- but of course first of all I'd appreciate it if the imaginative scenarios were clearly identified as such and set apart from the facts better.This message has been edited by Faith, 03-15-2006 09:20 AMThis message has been edited by Faith, 03-15-2006 09:46 AMThis message has been edited by AdminAsgara, 03-15-2006 08:49 AM

*sighs*Great, so we have to explain absolutely everything then.

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From reading the technical paper I linked to earlier, it seems the lack of a coarser grained component (i.e., the conglomeratic sequence), points to a marine depositional setting rather than a terrestrial setting for the original proto-sediments; which is consistent with previous theories regarding the geologic history of that particular terrane.

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I actually thought the same thing as soon as Rox mentioned that the conglomerates were absent. Conglomerates tend to be formed in terrestrial environments like river beds because the action of the river creates the rounded pebbles. So you tend to see conglomerates in river basins but not marine basins.If we could see the original rock (i.e. unmetamorphosed) we'd know immediately if it was formed in a terrestrial environment or not, because terrestrial rock is red or orange, on account of the iron in the rock reacting with the air. Offhand I can't remember if you can still tell from the chemical composition of the metamorphosed rock (I haven't done metamorphism for years).As well as that, any cross-bedding or similar structures not destroyed by the metamorphism are also indicative of how the rock originally formed.

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In another thread, I briefly touched on how the U.S. grew via island arc accretion south from about the Wyoming/Montana area. Wyoming is located on the Archean Wyoming craton and everything south and basically west are progressively younger accreted terranes - generally considered to be island arc terranes (volcanic island chains similar to Japan and Indonesia that develop along subduction zones).

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Look, Rox didn't pull this out of her ass or something. (Believe it or not, part of Ireland formed the same way.) An accreted terrane is a term describing a geological section that was formed from slices of rock formations; so I guess what you see is individual slices or areas, all crushed together, consisting of rock formations similar to what we see in Japan and Indonesia. We assume that, as the formations are similar and there is evidence of uplift and other tectonic action that squashed them together, they may have formed like Japan and Indonesia. Hence "progressively younger accreted terranes - generally considered to be island arc terranes" - because the evidence in the rock indicates that this is the most likely explanation.

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According to the linked paper (Ilg et al., 1996), the protosediments which later became the Vishnu Schist, are remants of one of those island arc terranes that collided with the continent back in the Precambrian (early Proterozoic time?).

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The Vishnu Schist is pretty old, but still - we see marine sediments, deformed and uplifted, which were intruded by igneous rock later. That's more or less consistent with what we expect to see in an island arc terrane.

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Evidence is given, but still the interpretations have that aura of fact. No contrary interpretations are suggested. There is no way to verify or falsify such an interpretation. This is what I find so frustrating about both OE and TOE discussions.

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The evidence suggests this is the most likely explanation. We verify or falsify it by examining the evidence - if we see what we expect to see if our explanation is correct, then the explanation is somewhat verified. If we see something unexpected, or something that is not possible for our explanation, it is falsified.Call it interpretation if you will, but that is what science is. Period. There isn't another 'interpretation' in this case because we don't have another that fits the evidence as well or better than our current one. This is not imagination, or speculation - it's called scientific investigation.Imagination and speculation are more the creationist's forte.

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"Gradually it was disclosed to me that the line separating good and evil passes not through states, nor between classes, nor between political parties either, but right through every human heart, and through all human hearts. This line shifts. Inside us, it oscillates with the years. Even within hearts overwhelmed by evil, one small bridgehead of good is retained; and even in the best of all hearts, there remains a small corner of evil." --Alexander Solzhenitsyn, The Gulag Archipelago"Those who fear the darkness have never seen what the light can do."

I haven't read your post carefully yet, but I have to point out that the first two quotes you are presenting are not mine though they are presented as if they were. The third is mine.

I think it would help if you simply left out the conjecture altogether myself. But if you are going to bring it in, then it has to be presented in terms of how you arrived at it. It's not fair to just describe a rock as a "marine environment." I didn't say she pulled it out of a hat. I assume it's standard geology. But my complaint is that the evidence usually isn't given, only the interpretation is given and it is given as fact rather than speculation, and to the poor layman it is often ALL that is given. It makes it impossible for another interpretation of the same phenomena to be offered. You don't give enough of the particulars for a person to think about and you don't like your interpretation being questioned because it's "science" and so on, but that attitude prevents your reader from thinking through the evidence, and especially if one is a YEC makes it nearly impossible to sort out enough fact from fiction to have an answer to you. But of course you don't want to hear the creationist's answer anyway. All you want to do is prove to us we're wrong, so there's not much motivation to be very careful about distinguishing the facts from the interpretations and imaginative scenarios. Boy is that a delusion.This message has been edited by Faith, 03-15-2006 09:40 AMThis message has been edited by Faith, 03-15-2006 09:43 AMThis message has been edited by Faith, 03-15-2006 09:44 AMThis message has been edited by AdminAsgara, 03-15-2006 08:50 AM

If layman was given the evidence and the skills and training to understand all of the information required...they wouldn't be a layman.The majority of people know that when such things are being discussed, they are getting the consensus opinion of the relevant scientists. If they don't want to accept their opinion they are entitled to.

Let's stick to the very narrowly defined topic folks. We are discussing the layering of the Grand Canyon from the bottom up. Any discussion speculation can be taken to another thread.This is solely about the physical rocks, their makeup, their relevance to each other as the thread progresses, and the mainstream geological explanations.

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AdminAsgara Queen of the Universe

http://perditionsgate.bravepages.com

On a debate board when the interpretation is in question, this doesn't fly.This message has been edited by AdminAsgara, 03-15-2006 08:51 AM

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In fact the exact conditions of the rocks that lead to such conjectures as "marine environment" are often left out or blurred over. I'd simply appreciate it if you and the other geologists would be alert to this effect and try to fill in the descriptive material that supposedly explains the scenarios -- but of course first of all I'd appreciate it if the imaginative scenarios were clearly identified as such and set apart from the facts better.

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It's not imagination. Please stop using that term, because it is entirely the wrong descriptive term to use for a scientific explanation based on research and extensive field studies.Anyway - I'm wondering if we should start on a less complex formation. Otherwise it'll take a very long time to explain all the relevent reasoning and lines of evidence behind every conclusion.

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"Gradually it was disclosed to me that the line separating good and evil passes not through states, nor between classes, nor between political parties either, but right through every human heart, and through all human hearts. This line shifts. Inside us, it oscillates with the years. Even within hearts overwhelmed by evil, one small bridgehead of good is retained; and even in the best of all hearts, there remains a small corner of evil." --Alexander Solzhenitsyn, The Gulag Archipelago"Those who fear the darkness have never seen what the light can do."

I'm taking this to a new topic.

You have NOTHING to say on the topic of dating. You cut and ran from that topic. If you are unable to defend your position regarding dating you will NOT bring it up.The dates of the layers are MEASURED just as you measure the ingrediants in a recipe.This message has been edited by AdminNosy, 03-15-2006 10:20 AM

I may have nothing to say about dating, but presenting a date as geologists do is nothing but interpretation, so THEY have nothing to say EITHER. A date in geological time cannot be a FACT, I don't care HOW much evidence supposedly supports it.

I would like for us to move back towards the topic. To do so I would like to make a summary of where we are. Then it was said that Granite is an igneous rock and was an intrusion into the sandstone layer that became the Vishnu Schist.So at this point we have solid evidence of at least four events.There was some rock forming event at some time in the past.That rock was worn down into sand.The sand was transformed in sandstone and then later into the Vishnu Schist.During the process there was a tectonic event and Zoroaster Granite intruded into the Vishnu Schist.Now there is no speculation in this summary so far that I can see.

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Aslan is not a Tame Lion

Don't worry. I will try very hard to keep this on topic and to make sure that there is no speculation. There is no need for either speculation or dates to prove that the Grand Canyon is old and that there was no Flood.I will work as hard as I can to keep this focused on the facts. Just be patient. We have only touched on two of the many, many layers of the Grand Canyon and only four specific events so far. Well, don't worry. We will try to simply present the facts and let the readers make their own judgements about the dates.

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Aslan is not a Tame Lion

You can almost say that was the order except for the last step. If I remember my geology correctly then a Schist is a metamorphic rock. Sedimentary rock can change into metamorphic rock in a number of way. It can buried and compressed due to the depth and heat at that depth or can be heated due to its proximity to a magma body. The latter is called contact metamorphism and there are some distinguishing characteristics for which I cannot recall at the moment. Rox or IRH might be able to help show us which it is.Since this particular Shist is so close to the granite my first guess would be contact metamorphism which would change the order of events a bit.1. Some silicate rock somewhere gets eroded into sand.
2. That sand is deposited which later becomes the Vishnu Sandstone.
3. A magma body intrudes into the sandstone causing contact metamorphism turning the sandstone into schist.
4. The magma never makes it to the surface and therefore cools as granite.Certainly our resident geology experts may have a better explanation as to the type of metamorphism that created the Schist.What is fun to note is that young or old the order of events does not change.

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Of course, biblical creationists are committed to belief in God's written Word, the Bible, which forbids bearing false witness; --AIG (lest they forget)