Stratigraphic Correlation

[thaumaturgy]

OK, I've heard some creationists here are quite unfamiliar with a standard Geology concept called stratigraphic correlation.

So this is an attempt to explain it.

Stratigraphic correlation is how we build a complete picture of rocks based on a sample of the various portions of the rocks.

We want to find out how far a rock layer extends in an area. We also may want to know how the environment of deposition changed across an area. If you are standing on a beach you are looking out at the ocean which is depositing sediments in one say, while the dunes you are standing on represent a completely different environment of deposition and some erosion.

When we look at rock cores or exposed "cuts" where rock layers are exposed in a layer we describe the rock and the particle size, and any fossils in them and their general appearance (color, features, etc.)

Then we may travel for miles in some other direction and find another exposed "cut" or look at some different rock core and describe the rock layers in it.

When we set these two descriptions side by side we can find commonalities and some cases where things are missing.

Look at this cartoon. It represents the descriptions from two exposures of several layers of rocks separated by 10 miles:

What you see are some layers, like C and F which look almost exactly alike. They have the same type of fossils and the same type of particle sizes (the little dashes indicate "clay", very fine particles). We assume C and F are correlated which means that they are likely different areas of a very large extent of the SAME environment of deposition and since this is a unique fossil we don't find earlier or much later, they represent the same time-frame as well.

Note how B and D are the same but they aren't at the same level! What this indicates is that LAYER E is MISSING in the first column and was probably eroded away at some places but not in all places. OR it was never deposited over in the area where the first set of layers was exposed. Perhaps the colum that contains E was in DEEPER WATER and the water didn't cover the land in the area of the first column so it didn't deposit any rocks.

Later we see B and D can be CORRELATED and that indicates the water covered all that area.

This is a simplistic gloss of how correlation works, but it underlies how geologists build big, detailed histories of very large areas of land.

Here's a picture of correlations that run down the entire WEST SIDE of the state of Kansas (note the little picture in the upper right corner that shows where the columns are from)

I know this is really hard to see (HERE's a larger version), but what it represents is the real power of being able to CORRELATE across big distances. It requires some advanced knowledge of geology, mineralogy, stratigraphy, and environmental depositional systems.

Ultimately you can generate some really nice pictures in 3 dimensions. Here's something called a FENCE DIAGRAM that represents correlation in 2 dimensions (X and Y) and in the 3rd dimension (the rock layers). The little "poles" in the fence diagram are the rock cores that were described and correlated. Attempts were made to interpolate the data between these datapoints.

For more information on STRATIGRAPHY and CORRELATION, check HERE or HERE.

(Resource 1)
(Resource 2)

 

[DeathMagus]

Is it telling that I saw the thread title "Stratigraphic Correlation" and immediately thought "Thaumaturgy is behind this?" Yes, I think it is telling, and rather wonderful.

Always a pleasure to read your technical, yet insightful posts, Thaum.

 

[dukeofhazzard]

I always learn something from your posts! I really enjoy reading them

 

[AV1611VET]

Let me take a crack at interpreting this, using Flood geology - (if I can).

Let's say that all four animals (trilobite, scorpion, sturgeon, and tusk?) are all alive at the same time, and it's prior to the Flood.

The column on the left is over water, and the column on the right is ten miles away, and over land.

So, just prior to the Flood we have:

• Column Left = C, A
• Column Right = B, E

Now comes the Flood, which would "triage" the animals into, from the bottom up: C, B, E, A.

The trilobites die first, sinking to the bottom of lake and land - (giving you the C and F above).

Next, the scorpions die and should produce B and D side-by-side.

Then the pachyderms die and should produce E on the right.

And finally, the fish die, and should produce A and A side-by-side.

Now what should we have?

• Column Left = C, B, A
• Column Right = C, B, E, A

But --- remember --- the agitation caused by the water would allow the heavier pachyderms to settle, followed by the lighter scorpions, and form your Column Right (over the land).

The reason the even lighter trilobites are not on top at Column Right could be because they died much sooner than the others, sank to the bottom, and were covered (locked in) by an initial subterranean blast.

Just a theory.

 

[Daffaforce]

You need many more additional factors for your "theory" to work, compared to the simple geologic explanation from thaumaturgy.

 

[DeathMagus]

Interesting theory, AV. Just one question, though. Wouldn't a subterranean blast of that magnitude generate some sort of sign in the rock layers that we'd be able to easily find?

 

[AV1611VET]

Interesting theory, AV. Just one question, though. Wouldn't a subterranean blast of that magnitude generate some sort of sign in the rock layers that we'd be able to easily find?

Yes --- and no.

It would have, IMO, left a hole that could have been closed by God later, when He cleaned up the mess.

Can't be proven, of course, but that's what I say all along.

There is no evidence (with possibly one exception) for the Flood.

 

[Split Rock]

Let me take a crack at interpreting this, using Flood geology - (if I can).

Let's say that all four animals (trilobite, scorpion, sturgeon, and tusk?) are all alive at the same time, and it's prior to the Flood.

The column on the left is over water, and the column on the right is ten miles away, and over land.

So, just prior to the Flood we have:

• Column Left = C, A
• Column Right = B, E

Now comes the Flood, which would "triage" the animals into, from the bottom up: C, B, E, A.

The trilobites die first, sinking to the bottom of lake and land - (giving you the C and F above).

Next, the scorpions die and should produce B and D side-by-side.

Then the pachyderms die and should produce E on the right.

And finally, the fish die, and should produce A and A side-by-side.

Now what should we have?

• Column Left = C, B, A
• Column Right = C, B, E, A

But --- remember --- the agitation caused by the water would allow the heavier pachyderms to settle, followed by the lighter scorpions, and form your Column Right (over the land).

The reason the even lighter trilobites are not on top at Column Right could be because they died much sooner than the others, sank to the bottom, and were covered (locked in) by an initial subterranean blast.

Just a theory.

The problem is that he is only giving you the index fossils for these strata, not all the fossils found in them. So, the layers with the fish may also have coral and a shell fish similar to the "tusk" but a different species. This has always been the issue with "hydrological sorting" ideas like Morris came up with... they don't actually describe what geologists find. Shellfish, for example, are found through out most of the geological column (in marine strata), although they change over time.

 

[DeathMagus]

Yes --- and no.

It would have, IMO, left a hole that could have been closed by God later, when He cleaned up the mess.

Can't be proven, of course, but that's what I say all along.

There is no evidence (with possibly one exception) for the Flood.

Then I'm confused as to why you feel the need to explain any of Thaum's post at all, if God can and does routinely "clean up" evidence of his work.

 

[AV1611VET]

Then I'm confused as to why you feel the need to explain any of Thaum's post at all, if God can and does routinely "clean up" evidence of his work.

God doesn't "routinely 'clean up' evidence of his work."

This was a one-time thing.

And I explained "Thaum's" post, because I feel he is drawing the wrong conclusion based on his interpretation of what he has presented to us.

 

[Loudmouth]

God doesn't "routinely 'clean up' evidence of his work."

This was a one-time thing.

And I explained "Thaum's" post, because I feel he is drawing the wrong conclusion based on his interpretation of what he has presented to us.

Then demonstrate that he has drawn the wrong conclusion. Form a hypothesis that makes predictions based on observed mechanisms that better describes the data.

 

[Naraoia]

The trilobites die first, sinking to the bottom of lake and land - (giving you the C and F above).

Next, the scorpions die and should produce B and D side-by-side.

Then the pachyderms die and should produce E on the right.

And finally, the fish die, and should produce A and A side-by-side.

Can you explain why they would die in that specific order?

But --- remember --- the agitation caused by the water would allow the heavier pachyderms to settle, followed by the lighter scorpions, and form your Column Right (over the land).

The reason the even lighter trilobites are not on top at Column Right could be because they died much sooner than the others, sank to the bottom, and were covered (locked in) by an initial subterranean blast.

Okay, here comes the nit-picking
Trilobites aren't all that light, they had calcified exoskeletons. By the way, they were most probably on the bottom anyway.

Your "pachyderms" are placoderms. "Pachyderms" are an obsolete group where rhinos and elephants and other mammals were lumped together by Cuvier.

Just a theory.

*hears echoes of "evolution is just a theory!"*

 

[Naraoia]

Your "pachyderms" are placoderms. "Pachyderms" are an obsolete group where rhinos and elephants and other mammals were lumped together by Cuvier.

My apologies! Just checked what you meant... yeah, not the fish. Sorry.

I suspect that "tusk" is more likely a coral than a tusk, by the way. And if that fish is a sturgeon I'll eat my boots.

 

[AV1611VET]

I'll checkmark out --- thanks.

 

[thaumaturgy]

Let me take a crack at interpreting this, using Flood geology - (if I can).

Interesting theory, but now look closely: the little DASHES indicate very very small particles. They are CLAY SIZED particles. just a couple MICRONS in size. It takes an exceedingly calm body of water to allow these puppies to settle out.

So the turbulence necessary to keep a trilobite, let alone an elephant aloft in a water column would not allow the settling of clay sized particles.

Also, we see many large extents of different energy regimes reflected here. This is where the famous HJULSTROM diagram comes in handy:

This tells me that very small particles are easily eroded and kept aloft at relatively low water velocity. You have to get really calm to dump out a clay sized particle.

(Also the little "horn like thing" is actually a type of ancient extinct coral called a HORN CORAL or "Rugose Corals". They are an extinct coral that first showed up during the Ordovician and lasted through the Permian --only on earth between about 450million years ago and about 250million years ago--

The other "Crab like thing" is actually a relative of the trilobite called a EURYPTERID. They existed in the rock record from the Cambrian to the Permian. So we know that these rocks are at the oldest, Permian in age and all except the bottom layers are younger than Ordovician!

Cool, huh?

 

[FishFace]

I'll checkmark out --- thanks.

He couldn't understand it so he ran off. Nice.

 

[Naraoia]

(Also the little "horn like thing" is actually a type of ancient extinct coral called a HORN CORAL or "Rugose Corals".

Yay, I've guessed right It's a coral

That one semester of geoscience did do me some good after all

 

[gamespotter10]

Let me take a crack at interpreting this, using Flood geology - (if I can).

Let's say that all four animals (trilobite, scorpion, sturgeon, and tusk?) are all alive at the same time, and it's prior to the Flood.

The column on the left is over water, and the column on the right is ten miles away, and over land.

So, just prior to the Flood we have:

• Column Left = C, A
• Column Right = B, E

Now comes the Flood, which would "triage" the animals into, from the bottom up: C, B, E, A.

The trilobites die first, sinking to the bottom of lake and land - (giving you the C and F above).

Next, the scorpions die and should produce B and D side-by-side.

Then the pachyderms die and should produce E on the right.

And finally, the fish die, and should produce A and A side-by-side.

Now what should we have?

• Column Left = C, B, A
• Column Right = C, B, E, A

But --- remember --- the agitation caused by the water would allow the heavier pachyderms to settle, followed by the lighter scorpions, and form your Column Right (over the land).

The reason the even lighter trilobites are not on top at Column Right could be because they died much sooner than the others, sank to the bottom, and were covered (locked in) by an initial subterranean blast.

Just a theory.

you're gonna try to tell me that not a single human slipped and fell and got fossilized in the precambrian rock?

oh, and if they were sorted by their ability to escape as you claim, then the turtles should be at the bottom, and the birds at the top. is this what we find? nope

 

[Bombila]

Nicely explained, Thaumaturgy.

I have a scattered grasp of geology, partially gleaned from ghostwriting papers in the early seventies for a writing-challenged geology grad student, so 'reminders' like these, along with more recent work, are like a refresher course.