YECs wonāt touch this sort of physical evidence. Of course it was the famous angular unconformity at Siccar Point Scotland which convinced geologist James Hutton in 1788 the Earth wasnāt young.
Itās a meeting abstract, Sal. FASEB publishes those abstracts, yes, but they arenāt papers. Iāve got lots of such abstracts that I have never listed on my cv.
No, my disclaimer will do just fine. As long as we can help you inform your students that they are not getting accurate information (aka facts) from you, then we are accomplishing something.
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).
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
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-conformityā¦
ā¦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.
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.
This weekās 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 ā an angular unconformity.
Note person in lower right for scale.
When I took this photograph I didnāt 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 ā 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 degā¦ 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.
