Cordova and Runyon on the fossil record

Well I don’t know how to do that. But yes, it is very inappropriate.

On the offending post, click the triple dots, then click the flag. Easy.

At what geologic level does the great unconformity reside?

If you mean the famous great unconformity in the Grand Canyon its surface lies between the Tapeats sandstone (approx. 550 MYA) and the metamorphic rocks of Granite Gorge (1.6 to 1.8 BYA).

Read about the geology for yourself here.

The Great Unconformity

Of course there are thousands of other examples of angular unconformities all over the planet.

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Which ones contain traces of life?

Going back pretty far, they contain pollen and bacteria. @r_speir, why not help me out here? Question to the YLC...Why Not Eras and Epochs?

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I have no idea what the percentage is but here is one example.

According to the caption the lower shale layer is full of trilobite fossils.

The pegmatitic granite is an intrusion dated at about 1.4 billion years ago and is part of the crystalline basement. Above the non-conformity (represented in red) is a Lower Cambrian sequence. One would expect an overall geometry of layers somehow parallel to the unconformity, but at the local scale it is not uncommon to observe contact at an angle, like the one in the picture. The Lower Cambrian sequence misses at this location the Zabriskie Formation (which is found immediately to the right of the area) and starts with the trilobite-rich Latham Shales, followed by the oncolite-rich Chambless Formation.

Marble Mountains, Cadiz (San Bernardino county), California

Source

ETA: For some reason the picture won’t load. Check the source link for the photo or right-click “open image in new tab”

ETA2: OK now the picture loads. Gremlins???

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I’ve been wondering the same thing about you, Mr. One Liner.

We could argue about that, but it would be off-topic. How about something on-topic for a change?

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So first of all, you are wrong about the non-conformity containing fossils. It is the Latham Shales above the non-conformity which is rich in trilobite fossils.

Second, this statement in the caption about the black line identifying the slanted contact angle of the sediment above the non-conformity…

…speaks clearly of two things:

a. By the time of the great Flood, the basement rock had already been pushed up at an angle and the non-conformity was already in place
b. That angle created a reservoir of sorts for the deposit of Flood sediments in the Latham Shales

Conclusion: You have just submitted an almost perfect example of how the Noahic Flood is validated in earth geology.

LOL! You should get a job as a fiction writer your imagination is so vivid!

Tell us again how your quiet gentle Flood produced ALL of these angular unconformities?

Pictures of Angular Unconformities

Bad tactics. You have to find an angular unconformity that specifically addresses his claims to present him with a dilemma. You need one that happens within the Phanerozoic and has fossils both below and above the unconformity.

Here’s another example I found.

This week’s Friday Field Foto is from an area just west of Death Valley called Darwin Canyon. As you can see, there is a sharp, angular contact between two sedimentary formations – an angular unconformity.

Note person in lower right for scale.

When I took this photograph I didn’t have any specific knowledge of this geology because we were driving between stops. But 2 minutes on the google machine uncovered this fantastic web resource – Death Valley Geology: A Field Guide and Virtual Tour by Steven G. Spear from Palomar College.

The information for this angular unconformity is here and this is what they have to say about it:

The layers below the unconformity are the lower Permian Darwin Canyon formation seen at the folds up-canyon. The layers on top are Triassic marine deposits (and may correlate to similar age strata in Butte Valley). The angular discordance of the unconformity is about 20 deg… The age of this unconformity has been quite well dated. The youngest fossils in the beds from under the unconformity are Wolfcampian fusilinids of the Panamint Springs member of the Darwin Canyon formation. The oldest fossils from the layers above the unconformity are Guadelupian (Capitanian) brachiopods and mollusks.

Source

Let the hand waving begin again. :slightly_smiling_face:

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That’s exactly what he said:

There is only one layer that could possibly be described as “lower shale layer”, and it’s the correct one. He even quoted the page as saying:

Above the non-conformity (represented in red) is a Lower Cambrian sequence.

The Lower Cambrian sequence misses at this location the Zabriskie Formation (which is found immediately to the right of the area) and starts with the trilobite-rich Latham Shales, followed by the oncolite-rich Chambless Formation.

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Another classic example is the (subtle) unconformity between the Ordovician and Silurian at this river cliff on the River Onny in the UK.


(Photo credit me)
Both the Purple Shales above and the Onny Shales below are highly fossiliferous.

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Much better.

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The problem with that is that the fossils are above the unconformity, which can be fit into the Flood time scale: below the unconformity, ancient, lifeless, pre-Flood; above it, life in Flood deposits.

Sure, I just wanted to make it clear that @Timothy_Horton description of the unconformity was correct. @r_speir asked for unconformities that “contain traces of life”, so it wasn’t really clear which of the 2 contacting strata he was interested in. The unconformity refers to the relationship between 2 layers, not a particular one.

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The point is that an unconformity with fossils above and below causes big problems for the flood model, as it requires sediment to be deposited, lithified, folded, and eroded, and then more sediment deposited atop the erosional surface, all in a few days.

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Those physical challenges are a huge problem for Flood geology even if the strata above and below contains no fossils. That’s the whole point. The “fossils” angle is just a distraction.