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Author | Topic: Sedimentary Rock Formation | |||||||||||||||||||||||||||||
TheLiteralist Inactive Member |
A common YEC position is that all, or nearly all, sedimentary rock layers are due to waterborne sediments. This would be particularly true of fossil-bearing layers.
Yet, I think traditional geology holds that some of the layers are the result of water-borne sediments that were cemented by minerals while others are the result of wind-carried sediments that have compacted into stone. (And, perhaps, I have over-simplified it). At any rate, I would like to see a discussion of why certain layers could NOT have been the result of water-borne sediments. I refer specifically to fossil-bearing layers that contain fossils of land-dwelling organisms. AbE: I guess it should be noted for those who might not know...I am a YEC. --Jason This message has been edited by TheLiteralist, 08-29-2005 04:19 AM
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AdminNosy Administrator Posts: 4754 From: Vancouver, BC, Canada Joined: |
Thread moved here from the Proposed New Topics forum.
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Coragyps Member (Idle past 761 days) Posts: 5553 From: Snyder, Texas, USA Joined: |
Some landforms are just incapable of being formed underwater. Geologists (and I'm not one) are not dummies: they have actually studied such things as the steepest angle that a pile of sand, like a dune, can form under a desert sky vs. under water. It's maybe 30 degrees in air, and way under ten degrees under water. You can do an experiment like that at home with a jar, some water, and a handful of sand. Particle-size distribution is different in wind-blown and water-carried sediment, too, and is subject to experiment to verify which can cause what.
As to fossils, I have read of fossilized dinosaur nests that were buried by dunes - no water involved at the time of burial. My bet would be that, in most such cases, groundwater was responsible for bringing in the minerals to consolidate the sediment and fossilize the eggs. But you can bet that the folks digging the nest out paid very close attention to all the features that point to whether the deposit was wind-deposited or not. This message has been edited by Coragyps, 08-29-2005 10:07 PM
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RAZD Member (Idle past 1431 days) Posts: 20714 From: the other end of the sidewalk Joined: |
there are fossils of marks scraped into the sand by grass-like plants which are identical to such formations visible today wherever you have windblown dune grass.
you do not get this underwater. we are limited in our ability to understand by our ability to understand RebelAAmerican.Zen[Deist
{{{Buddha walks off laughing with joy}}}
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Jazzns Member (Idle past 3938 days) Posts: 2657 From: A Better America Joined: |
The largest problem an all water based theory has is how evaporites get deposited. These are structures that form literally BECAUSE of the lack of water.
The only mechanism that prominent YECs can offer is some sort of bizzare geothermal underwater chemical reaction but there are TONS of problems with that. The biggest is probably trying to explain why the old evaporites formed different than the ones that look exactly the same that ARE forming today via evaporation. No matter what you might be able to say about how water MIGHT be able to form something sort like a dune, you can't get away from the evaporites that absolutly need dry eolian environments to form. No smoking signs by gas stations. No religion in the public square. The government should keep us from being engulfed in flames on earth, and that is pretty much it. -- Jon Stewart, The Daily Show
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Nuggin Member (Idle past 2519 days) Posts: 2965 From: Los Angeles, CA USA Joined: |
Not to mention that water tends to sort the granuals. If these layers were being deposited in one fell swoop by a single great flood, wouldnt we expect heavy layers at the bottom and silty layers on top
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Nighttrain Member (Idle past 4020 days) Posts: 1512 From: brisbane,australia Joined: |
Hi, Jason, quickest way I know to determine if sediments have been water-borne is to look at the edges of the particles/rocks. If they are rounded or worn, they were normally tumbled by water. Sharp edges remain even if erosion caused a slide down a mountainside. While brittle rocks can splinter in a watercourse, it doesn`t take much distance to round off the edges. So if we looked at strata and find little or no rounding, it`s almost certain it has never been in a flood, let alone 'The Biggie'.
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TheLiteralist Inactive Member |
Hi Coragyps,
Coragyps writes: Some landforms are just incapable of being formed underwater. Geologists (and I'm not one) are not dummies: they have actually studied such things as the steepest angle that a pile of sand, like a dune, can form under a desert sky vs. under water. It's maybe 30 degrees in air, and way under ten degrees under water. You can do an experiment like that at home with a jar, some water, and a handful of sand. Particle-size distribution is different in wind-blown and water-carried sediment, too, and is subject to experiment to verify which can cause what. Well, I think those are some good points...I'd like to see some of the resident geologists expand on these ideas a bit more.
As to fossils, I have read of fossilized dinosaur nests that were buried by dunes - no water involved at the time of burial. My bet would be that, in most such cases, groundwater was responsible for bringing in the minerals to consolidate the sediment and fossilize the eggs. Okay. I have heard such things myself. A question that comes into my mind, though, is how the egg was preserved long enough to undergo fossilization.
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TheLiteralist Inactive Member |
Hi RAZD,
Well, the grass-marks-on-dunes fossils I've never heard of before. It brings to mind a slightly different issue. Particularly fossils of ripples in sand (like you see underwater at the beach) and footprints of various creatures. I can envision these types of delicate fossil imprints occuring only if the sand contained water and some sort of curing agent...sort of like how concrete works. Otherwise, it seems like the mark would quickly disappear. How COULD a grass mark on a dune become fossilized? (Just curious as to what the traditional geology explanation is...if there is one). --Jason
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TheLiteralist Inactive Member |
Hi Nuggin,
The only answer I can muster for that objection to the Flood is that the Flood might have had several stages and various events (volcanic eruptions, earthquakes, tsunamis, recessions, etc.)...so the layers probably wouldn't represent "one fell swoop." Although, there probably would be a few places, particularly during the time after the rains and before the final recessions, where such a pattern would be made. However, this is sort of off-topic. I am not asking for evidence against the Flood per se. I am asking for evidence that not all sedimentary rock layers were not made by water-borned sediments. See, it would be a possibility, even under the evolution/billions-of-years paradigm, for ALL the layers to be the result of water-borne (but non-Flood) sediments. But, traditional geology claims that some of the sediments in the sedimentary rock layers are not water-borne. --Jason
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Jazzns Member (Idle past 3938 days) Posts: 2657 From: A Better America Joined: |
I am asking for evidence that not all sedimentary rock layers were not made by water-borned sediments. Evaporites. QED. No smoking signs by gas stations. No religion in the public square. The government should keep us from being engulfed in flames on earth, and that is pretty much it. -- Jon Stewart, The Daily Show
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TheLiteralist Inactive Member |
Hi Jazzns,
I'm not ignoring your point about evaporites. I thought your point was a thoughtful one. I just wanted to do a little reading up on evaporites, first. I don't even know the YEC position on evaporites...let alone traditional geology's position (except for the overview of both positions, which you gave). --Jason
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Coragyps Member (Idle past 761 days) Posts: 5553 From: Snyder, Texas, USA Joined: |
I don't even know the YEC position on evaporites....
I've seen the proposal that all that 800-degree water from the "fountains of the deep" was saturated with salt, and that as it mixed with cool water on the surface, the salt fell out of solution to form, for example, the Zechstien and Louann Salt - both massive sodium chloride deposits. I see a couple of big, large, and humungeous problems with this:1) Saturated salt water at 700 F contains, if I recall right from the Halliburton Cementin Manual, about 50% salt by weight. If you mix a sample of that brine with an equal weight of freezing-cold fresh water, the mixture will be at a temperature of 350 F or so, and contain 25% salt. However, water at room temperature will still hold 26% salt by weight. So no salt can drop out in this scenario. 2) Noah might have been a little uncomfortable in 350 degree water.....
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edge Member (Idle past 1732 days) Posts: 4696 From: Colorado, USA Joined: |
At any rate, I would like to see a discussion of why certain layers could NOT have been the result of water-borne sediments. I refer specifically to fossil-bearing layers that contain fossils of land-dwelling organisms. Does this mean that you deny modern sand dunes are the product of eolian deposition? Or do you deny that eolian dunes formed in the past, but certainly can in the present? If so why? Dunes are modern analogs to features in the geological record.
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TheLiteralist Inactive Member |
Hi edge,
Does this mean that you deny modern sand dunes are the product of eolian deposition? Or do you deny that eolian dunes formed in the past, but certainly can in the present? If so why? Dunes are modern analogs to features in the geological record. Do these ancient dunes contain fossils, by any chance? Is there anything in the dune-analagous features that would absolutely prevent a watery origin? --Jason--Jason
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