Flood Geology (contd. from "Carnivorous animals...")

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touchingcloth
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Flood Geology (contd. from "Carnivorous animals...")

Post by touchingcloth »

A continuation of a discussion between myself and Jac in another thread (http://discussions.godandscience.org/vi ... 105#p76709).
I've picked out all the posts between us from the other thread (so other readers don't have to do any trawling!) and dumped them here so we can carry on where the other thread left off.
touchingcloth wrote:Jac - (just to pull back a bit to the initial topic of the thread, if that's ok...) presumably you attribute the time of the fall to being after the appearance of the first human...just curious what you make of the fossil evidence of carnivorous animals that is orders of magnitude older than fossils of the first humans? (Apologies if this has been addressed already)
Jac3510 wrote:Not much, TC. That would only be a problem if I assumed the geological evidence indicated that some fossils are "orders of magnitude older than fossils of the first humans." You have to assume uniformitarianism to get that, which is, at best, a philosophical, not scientific, position. As it stands, I believe in a global flood, which I take as a better explanation for modern geological structures, and thus, for the dating of fossils. Nothing, I presume, you haven't heard before.
touchingcloth wrote:Even considering the strata upon strata between the latest dinosaurs and earliest humans?
Jac3510 wrote:Yes. You have to realize that the assumption that strata only get built up by millions of years is a philosophical notion on your part. There's no reason to suppose that the Flood would bury them in the same places.
touchingcloth wrote:Well assuming that strata slowly build up is one part of it, as is dating rocks in the same strata as certain fossil species, as is noticing that certain species of animals (well, whole orders of animals in fact) consistently turn up in deeper strata than others.

There's not reason to suppose that a flood would bury them all in the same place, but there's even less reason to think that one would sort them (and rocks) in this manner.
Jac3510 wrote: Remember that at the time of the Flood, pretty much all humans were living in the same place. You wouldn't expect to find human fossils buried throughout the stata, especially not on a global scale.
touchingcloth wrote: You'd expect them to be in the same (or at least overlapping) strata as their supposed contemporaries, though.

Where is the place where all humans were living at the time of the flood?
Jac3510 wrote:
touchingcloth wrote:You'd expect them to be in the same (or at least overlapping) strata as their supposed contemporaries, though.
"their" is ambiguous. Could you restate?
Where is the place where all humans were living at the time of the flood?
The Middle East.
touchingcloth wrote:
Jac3510 wrote:
touchingcloth wrote:You'd expect them to be in the same (or at least overlapping) strata as their supposed contemporaries, though.
"their" is ambiguous. Could you restate?
In other words you'd expect to find human remains in at least some corresponding strata with those that dinosaurs are found in, wouldn't you? (Pardon the question, but you're "pure" YEC aren't you, not progressive or anything, just a single act of creation?)
Jac3510 wrote: As I said, there were a relatively small number of humans living in a small area. I would not expect to find them buried together, especially not over the entire world. Further, humans are a bit smarter than animals, so they could have survived the flood longer, meaning any human remains that would have been fossilized during the flood--and there wouldn't have been many--would have been more likely to be found in higher strata.

And I'm not sure what you mean by "a single act of creation." I think creation took place progressively over six days.
touchingcloth wrote:
Jac3510 wrote: As I said, there were a relatively small number of humans living in a small area. I would not expect to find them buried together, especially not over the entire world. Further, humans are a bit smarter than animals, so they could have survived the flood longer, meaning any human remains that would have been fossilized during the flood--and there wouldn't have been many--would have been more likely to be found in higher strata.
But it is plausible that there will be some human remains in strata in the middle east that are deeper than corresponding strata in, say, Australia that contain dinosaur remains, right? Or in other words, finding human remains below the Kt boundary is entirely plausible?
Jac3510 wrote:To directly answer your question: possible? Yes. Plausible? That may be a stretch. Bear in mind that the YEC view has the flood happening very early in human history--maybe only a couple thousand years.

More generally, the KT boundary is problematic enough in itself for a lot of reasons I won't go into here. Further, you are still assuming uniformitarian geology. Who says that much of the pre-flood strata were not rearranged by the Flood?

Put the question this way: suppose there was a global flood during the very early portion of human history. What would you expect to find in the rock strata and fossil layers? You would expect a fossil record composed primary of marine and plant life, and then to a much lesser extent of animal life, and to a far, far lesser extent some human life. That human life would not be uniformly distributed throughout the strata but would be concentrated in the upper. You would also expect evidence of very quickly formed rock layers, of marine animals at the tops of mountains, of trees and even animal fossils protruding through various strata, and evidence of animals dying and being fossilized in an instant, and this, all over the globe, etc.

Guess what? We find exactly all these things. Now, at this point, we are turning the conversation more in the direction of a discussion about the Flood, which is not what this thread is about, so if you want to continue this line, I'd suggest opening a thread on it. My only point, though, in bringing this to your attention is that the fossil record is perfectly consistent with what we would expect in a YEC model, which, I believe, was the essence of your question.

Now, I'm not a geologist, and I don't spend a ton of time focusing on the geological defenses of YEC. Most of what I know are things I've picked up from here or there. My primary area of study is in biblical studies, philosophy, and Hebrew. I may have to do some digging to get the answers to some of your questions. But I think the general framework I've provided is sufficient to provide at least a broadly conceptual answer.
touchingcloth wrote:
Jac3510 wrote:Put the question this way: suppose there was a global flood during the very early portion of human history. What would you expect to find in the rock strata and fossil layers? You would expect a fossil record composed primary of marine and plant life, and then to a much lesser extent of animal life, and to a far, far lesser extent some human life. That human life would not be uniformly distributed throughout the strata but would be concentrated in the upper. You would also expect evidence of very quickly formed rock layers, of marine animals at the tops of mountains, of trees and even animal fossils protruding through various strata, and evidence of animals dying and being fossilized in an instant, and this, all over the globe, etc.
I'll put aside the various problems I have with this, and agree with you that given certain conditions a global flood could result in animals being fossilized in that order.

However, that doesn't account for older rocks being found in deeper strata; a 2 week old igneous rock is much the same as a thousand year old one, or a million year old one. As I've agreed that there are elements of plausibility to your flood hypothesis as an interpretation of the evidence, I'd hope you would agree that gauging the age of when a strata was laid down by the age of the rocks it contains is also a reasonable use of the evidence?
Whew! That was a mammoth post to edit!
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Re: Flood Geology (contd. from "Carnivorous animals...")

Post by Jac3510 »

Thanks for taking the time to break up the thread, TC. Makes keeping track of conversations, and keeping them on topic, much easier :)
TC wrote:However, that doesn't account for older rocks being found in deeper strata; a 2 week old igneous rock is much the same as a thousand year old one, or a million year old one. As I've agreed that there are elements of plausibility to your flood hypothesis as an interpretation of the evidence, I'd hope you would agree that gauging the age of when a strata was laid down by the age of the rocks it contains is also a reasonable use of the evidence?
I certainly agree it's reasonable. Depending on your assumptions, I think it's a pretty obvious conclusion to make. I'm sure, though, you would agree that just because something is reasonable doesn't make it true, although it does seem that something must at least be reasonable to be true (assuming we ignore quantum mechanics :p)!

It seems, though, that you have two assumptions here that require, at minimum, that pesky uniformitarianism again:

1. That you know "the age of when the strata was laid down", and
2. That you know "the age of the rocks it contains."

Correct me if I'm wrong, but don't things like fossil layers, erosion patters, radiometric dating, and other such factors play heavily in discovering the age of these two items? And if so, don't you see how a global flood would impact the dating for both?

Let me put the question to you this way: suppose with me, for the sake of argument, that there was a global flood. If you assumed that there never had been, and rigidly applied uniformitarianism in examining the existing rocks and strata, wouldn't the very factors just mentioned actually confuse you as to what actually had happened?
Proinsias wrote:I don't think you are hearing me. Preference for ice cream is a moral issue
And that, brothers and sisters, is the kind of foolishness you get people who insist on denying biblical theism. A good illustration of any as the length people will go to avoid acknowledging basic truths.
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Re: Flood Geology (contd. from "Carnivorous animals...")

Post by touchingcloth »

Jac3510 wrote:It seems, though, that you have two assumptions here that require, at minimum, that pesky uniformitarianism again:

1. That you know "the age of when the strata was laid down", and
2. That you know "the age of the rocks it contains."

Correct me if I'm wrong, but don't things like fossil layers, erosion patters, radiometric dating, and other such factors play heavily in discovering the age of these two items? And if so, don't you see how a global flood would impact the dating for both?

Let me put the question to you this way: suppose with me, for the sake of argument, that there was a global flood. If you assumed that there never had been, and rigidly applied uniformitarianism in examining the existing rocks and strata, wouldn't the very factors just mentioned actually confuse you as to what actually had happened?
Can I ask what you mean by uniformitarianism (so I don't misunderstand you!)?

A global flood would certainly impact things like fossil layers and erosion patterns...but the only effect - as far as I can comprehend - it would have on rocks of different ages would be of jumbling them up, not sorting them.
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Re: Flood Geology (contd. from "Carnivorous animals...")

Post by Jac3510 »

Can I ask what you mean by uniformitarianism (so I don't misunderstand you!)?
Wiki's definition, which reflects my own understanding:
  • Uniformitarianism, in the philosophy of naturalism, assumes that the same natural laws and processes that operate in the universe now, have always operated in the universe in the past and apply everywhere in the universe. It is frequently summarized as "the present is the key to the past," because it holds that all things continue as they were from the beginning of the world.
A global flood would certainly impact things like fossil layers and erosion patterns...but the only effect - as far as I can comprehend - it would have on rocks of different ages would be of jumbling them up, not sorting them.
Why would it have a problem sorting them? We've known that water (and air) sort sediments into discernible strata for a very long time. Creationists are fond of citing a '97 issue of Nature in which spontaneous stratification was experimentally observed. Add to that the well known phenomena of horizontal stratification, and you can see it the way creationists do: during the Flood, the layers were formed not one after another, but simultaneously, as the various rocks sorted themselves in spontaneous stratification.

Of course, we could also point to the often cited Mt St Helens eruption, which has sorted layers produced in a very short period of time. Creationists are sometimes accused of comparing apples and oranges, since those layers are made of volcanic rather than sedimentary rocks, but if the issue under discussion is spontaneous stratification, it seems the same principles could apply to one as well as the other.

Maybe I'm misunderstanding you, though, since I am pretty sure you are already aware of the above. So which part of the sorting do you have a problem with?
Proinsias wrote:I don't think you are hearing me. Preference for ice cream is a moral issue
And that, brothers and sisters, is the kind of foolishness you get people who insist on denying biblical theism. A good illustration of any as the length people will go to avoid acknowledging basic truths.
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Re: Flood Geology (contd. from "Carnivorous animals...")

Post by touchingcloth »

Jac3510 wrote:Maybe I'm misunderstanding you, though, since I am pretty sure you are already aware of the above. So which part of the sorting do you have a problem with?
Sorry - I should have made it more clear. It's not the stratification based on the physical properties of rocks/dirt that I have issue with (you just have to shake some mud and water up and watch it settle to realise that), so I totally accept that flooding would lead to stratification based on the physical properties of stuff mixed up with the flood waters.

My problem with it is that the strata also contain igneous rocks, and these appear very strongly to be sorted by their age, rather than by their physical properties. So I guess my question is how would a flood lead to strata with rocks sorted by age, rather than by mass/density/surface area etc.?
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Re: Flood Geology (contd. from "Carnivorous animals...")

Post by Jac3510 »

My problem with it is that the strata also contain igneous rocks, and these appear very strongly to be sorted by their age, rather than by their physical properties.
Sorry to be nitpicky, but I want to avoid assumptions as much as you do. So that I don't misunderstand you again, could you restate this without using the word "age," which is, in many ways, a major issue under discussion? What I mean is, could you rephrase with specific reference to the features of the rocks that are used to date them rather than us assuming the conclusions of what I've been calling uniformitarian geology? Given your specific mention of igneous rocks, I think I know what you are referring to, but I'd just like to be more explicit. :)
Proinsias wrote:I don't think you are hearing me. Preference for ice cream is a moral issue
And that, brothers and sisters, is the kind of foolishness you get people who insist on denying biblical theism. A good illustration of any as the length people will go to avoid acknowledging basic truths.
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Re: Flood Geology (contd. from "Carnivorous animals...")

Post by touchingcloth »

Jac3510 wrote:
My problem with it is that the strata also contain igneous rocks, and these appear very strongly to be sorted by their age, rather than by their physical properties.
Sorry to be nitpicky, but I want to avoid assumptions as much as you do. So that I don't misunderstand you again, could you restate this without using the word "age," which is, in many ways, a major issue under discussion? What I mean is, could you rephrase with specific reference to the features of the rocks that are used to date them...
No problem - "these appear very strongly to be sorted by the ratio of isotopes they contain, rather than by their physical properties".
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Re: Flood Geology (contd. from "Carnivorous animals...")

Post by Jac3510 »

I figured you meant as much. Now, given your usage of the word "very strongly," can you provide me a few examples of what you are referring to exactly? I say 'exactly' on purpose here. There is no doubt in my mind that rocks do seem "very strongly" assorted by their age if we take all the usual uniformitarian assumptions and ignore the possibility of a global flood. So, for instance, rocks at a lower strata would be older than rocks at a higher strata; fossils in the lower strata would be from older creatures (which we know because they are in older strata . . . always did seem a bit circular to me, but moving on); etc.

But if we look only at the isotopes, we are specifically looking at the K-AR ratios (yes, no?). So are you suggesting that rocks in higher strata have more AR than rocks rocks at lower strata, with the inverse being true with regard to K? I'm certainly sure you can point to high-AR containing rocks near the surface and low-AR rocks deep in the layers, but we are looking for "very strong" correlation. I don't know that it is as universal as you imply, given what little I do know about the types of rocks found in various layers (say, in the Grand Canyon) and the way rocks are often dated by their strata and the fossils associated with them.

So, bottom line, can you provide me some "very strong" evidence that rocks found in lower strata contain a higher ratio of K to AR than rocks found at higher strata? I'm certainly not saying you can't. I've not done much research on the topic, and I would be very interested to see what YECs have to say about such things. But there's no need to go running off looking for such research until I know what I'm looking for, is there?
Proinsias wrote:I don't think you are hearing me. Preference for ice cream is a moral issue
And that, brothers and sisters, is the kind of foolishness you get people who insist on denying biblical theism. A good illustration of any as the length people will go to avoid acknowledging basic truths.
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Re: Flood Geology (contd. from "Carnivorous animals...")

Post by touchingcloth »

Jac3510 wrote:But if we look only at the isotopes, we are specifically looking at the K-AR ratios (yes, no?). So are you suggesting that rocks in higher strata have more AR than rocks rocks at lower strata, with the inverse being true with regard to K?
Not exclusively K-Ar dating, but a combination of that method along with uranium-lead, lead-lead and a number of others. But you got the gist of it (although it's not so much that rocks/minerals at deeper strata will have more Ar than those in shallower strata, but that the ratio of K:Ar will be more in favour of Ar in deeper samples...).
Jac3510 wrote:So, bottom line, can you provide me some "very strong" evidence that rocks found in lower strata contain a higher ratio of K to AR than rocks found at higher strata? I'm certainly not saying you can't. I've not done much research on the topic, and I would be very interested to see what YECs have to say about such things. But there's no need to go running off looking for such research until I know what I'm looking for, is there?
I've grabbed a few papers that show a range of different radiometric dating methods - I selected ones where each article itself shows a range of strata, and I've also got a couple of articles that overlap with each other on dates. Bear with me!

First up 3 papers all making use of uranium-lead dating: And secondly a couple of papers making use of the K-Ar method: So in summary that collection of papers shows the following strata and their corresponding isotope-derived dates:
  • Ordovician - 458Ma
  • Silurian - 439Ma
  • Permian-Triassic extinction - 253Ma
  • Permian-Triassic boundary - 235Ma
  • Mid-Triassic - 221Ma
  • Late-Triassic - 210Ma
  • Eocene - 45Ma
  • Miocene - 12Ma
Don't forget that all of those geologic periods were identified in strata well before radiometric dating was made possible.
I believe that prior to the 20th century the working assumption was that deeper strata were older, and that higher strata were built up slowly over time. Radiometric dating seems to confirm the assumption that deeper=older, but forced a rethink in the assumption about the speed at which strata were deposited (the pre-20th century notion being that, say, X feet of sediment takes X years to form. Radiometric dating showed that different strata were laid down at different rates). The papers cited above aren't even the tip of the iceberg of the huge volume of research that confirms this.
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Re: Flood Geology (contd. from "Carnivorous animals...")

Post by Jac3510 »

Thanks much. Exactly what I was asking for. Give me some time to dig into it.
Proinsias wrote:I don't think you are hearing me. Preference for ice cream is a moral issue
And that, brothers and sisters, is the kind of foolishness you get people who insist on denying biblical theism. A good illustration of any as the length people will go to avoid acknowledging basic truths.
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Re: Flood Geology (contd. from "Carnivorous animals...")

Post by touchingcloth »

No worries - I'll keep my eye out for any articles that happen to have the full text available for free online (the cited ones are all abstracts).
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Re: Flood Geology (contd. from "Carnivorous animals...")

Post by Jac3510 »

Abstracts aren't a problem. I work in a library. I can get pretty much anything for free through our ILL system 8)
Proinsias wrote:I don't think you are hearing me. Preference for ice cream is a moral issue
And that, brothers and sisters, is the kind of foolishness you get people who insist on denying biblical theism. A good illustration of any as the length people will go to avoid acknowledging basic truths.
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Re: Flood Geology (contd. from "Carnivorous animals...")

Post by Jac3510 »

TC,

Quick update. The idea coming out of creationist organizations like ICR seems to be that decay rates were highly accelerated during the Flood year. I'm looking for the mechanism (some of the papers I've looked at are rather technical) and will get back to you.

My first thought is that if they are right on this, it could certainly, in principle, explain the long ages implied by radioisotopes. I'm not sure, though, that by itself accounts for the sorting. In principle, even if true, you wouldn't necessarily expect rocks in deeper strata to decay more quickly than rocks in those closer to the surface (which is why I'm looking for the suggested mechanism). It would seem, though, if they have some reason to believe that deeper rocks accelerate their decay faster, you have a basic principle by which to explain what you are asking about. Obviously, you would then have to go back and apply the math to each layer, but that's the beauty of science, isn't it? Predictions and all that.

Will get back soon enough.
Proinsias wrote:I don't think you are hearing me. Preference for ice cream is a moral issue
And that, brothers and sisters, is the kind of foolishness you get people who insist on denying biblical theism. A good illustration of any as the length people will go to avoid acknowledging basic truths.
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Re: Flood Geology (contd. from "Carnivorous animals...")

Post by Canuckster1127 »

Rich references this and links to it from the main site. It may help to frame some of the issues and the claim of possible variants in decay rates.

http://www.lpl.arizona.edu/~matthewt/yeclaimsbeta.html
Radiometric Dating Problems with radiometric dating techniques are greatly overstated by most young-Earth advocates. They often cite isolated instances of implausible dates, but these are generally caused by obsolete dating methods, contamination that a good scientist would detect (and which does not affect the large majority of dates), or by attempting to date materials that are younger than the dating method's margin of error (using radiometric methods to date recent Hawaiian lavas or living sea creatures, for example, is akin to using an unmarked yard-long stick to measure the thickness of a human hair). Most modern radiometric dating uses the isochron method, which measures several different samples (and sometimes different decay paths) and correlates them. The isochron method basically cross-checks itself constantly, and results that do not represent real ages will fail the isochron tests. Consequently, the isochron method does not require any assumption about initial amounts of parent and daughter elements (a common young-Earth objection to radiometric dating). An important consideration with the isochron method, however, is to know what it is that you're dating. Plotting several samples on an isochron will tell you how long ago the samples were separated from one another. For samples from the same lava flow, this will give you the age of the lava flow. But for samples from different flows, there can be a residual isochron giving the age of the melting event in the Earth's mantle from which the flows were derived. This is exactly what ICR geologist Steve Austin measured in the Grand Canyon. He claims that Rb/Sr isochron dating of lavas at the top of the Grand Canyon gives ages older than Grand Canyon basement rocks (ICR Impact #224, http://www.icr.org/pubs/imp/imp-224.htm). However, since Austin's samples came from several different flows, he could not have been dating the age of a single flow, rather he was dating the magma chamber beneath the Grand Canyon, from which all of the flows came. Although Austin claims that his "anomalous ages" cast doubt on radiometric dating in general, the fact is that geochemists often use the same method Austin used to date melting events much earlier than the formation of the flows themselves. For a more detailed discussion of ICR's "Grand Canyon Dating Project," see Stassen (1999), http://www.talkorigins.org/faqs/icr-science.html. Another common objection to radiometric dating is that addition or removal of parent or daughter elements may have occurred. However, in most cases this would leave tell-tale chemical clues that scientists could detect (and indeed this frequently happens), and furthermore such contamination could not possibly account for all of the world's radiometric measurements, which are in good agreement. Finally, radioactive decay rates are known to be constant under all relevant physical conditions. The fact is that, although radiometric dating is imperfect like any other science, there is tremendous overall agreement among radiometric ages, as well as with stratigraphic (relative) ages, giving very strong circumstantial evidence for the reliability of radiometric dating methods. For a general overview of radiometric dating, see Radiometric Dating: A Christian Perspective by Christian geologist Roger Wiens (http://asa.calvin.edu/ASA/resources/Wiens.html).
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Re: Flood Geology (contd. from "Carnivorous animals...")

Post by touchingcloth »

Jac3510 wrote:My first thought is that if they are right on this, it could certainly, in principle, explain the long ages implied by radioisotopes. I'm not sure, though, that by itself accounts for the sorting. In principle, even if true, you wouldn't necessarily expect rocks in deeper strata to decay more quickly than rocks in those closer to the surface (which is why I'm looking for the suggested mechanism). It would seem, though, if they have some reason to believe that deeper rocks accelerate their decay faster, you have a basic principle by which to explain what you are asking about.
As in, for example, heat & pressure differences at deeper strata affecting decay rates?

I'd be interested to see what you manage to dig up - any mechanism would have to account for both alpha and beta decay (K-Ar relies on beta/inverse beta decays, U-Pb relies on a series of alpha and beta decays. It would also have to account for U-Pb relying on 2 separate decay series (U238 - Pb206 & U235 - Pb207) both with different half-lives and different number of alpha/beta decays in the series.
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