Evidence that the Great Unconformity did not Form Before the Strata above it

Why not?Are you saying that the upper sand was deposited at the same time as the dune beneath it?So, nothing happened in between, like a change in wind direction or any wind erosion? Well, that's weird since we see things that look exactly like it in the geological record. Of course (ignoring for the moment the misuse of engineering properties of materials) they occur in water. We see them also. But they are different, as I have previously explained.

Well, for one, it allows us to redefine what erosion is.Evidently...

I see. So ANY time gap now makes for an angular unconformity? We don't need the millions of years then? Welcome to the Flood time frame.

I am sure you must have evidence. Would you like to share it with us?

I don't know of any limitations. Who said we did? In fact, I think Percy has spedifically stated that the duration of an erosional event is unknown. It's just a gap in the rock record. Do you think that gaps record time? The geological record is not a tape recorder, Faith. The question is how long did it take to deposit the rocks, not how long to erode them away. II could snip an hour of tape out in minutes. That tells you nothing about how long it took to record that tape.

Of course we can often set minimum time spans; for example we can say with a very high confidence level that the Great Unconformity represents a gap of over two billion years since it took over two billion years to lay down the Super Group plus some unknown period of time to erode it away.

This is a travesty and a distraction from the topic of this thread.

Hi edge,Have you ever seen the upper surface of the Navajo Sandstone? It's the kind of thing that's a bit difficult to find on the internet unless you know the name of a place where you can look at it, and I do.It's in Arches National Park, I was just there looking at it a couple of weeks ago. WOW, you can see the dunes and the interdune areas on the top of it. I have better pictures than this but my wife has my camera in Denver at the moment. All the white sandstone from the forefront is Navajo. Edited by petrophysics1, : No reason given.

There's still no indication that my point has gotten across, so I shall repeat it again. Whether you're making points about Mosaic Canyon (as you say you are now), or about Siccar point (as you have in the past), or about the Great Unconformity (as you also have in the past, and which is the subject of this thread), what happens is that you raise questions about details having nothing to do with angular unconformities. If these questions are relevant to your point then that's fine. If not, and the indications I have are that they are not (again, see Message 550), then please keep the focus of your discussion on those parts of the image that are relevant to how you believe angular unconformities are created.

Since Faith hasn't replied yet and since I do think I understand what she means, let me relate my understanding of what Faith's saying in my own words. Fatih's corrections should be helpful in understanding her viewpoint:

1. Before the flood there were no sedimentary layers anywhere, not on land or sea bottom. There was limestone and clay and shale and slate and sandstone and so forth, but evidently not organized into sedimentary layers.
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2. The flood scoured all this material off the land down to bedrock (Faith's definition of "bedrock" isn't clear to me). This is the only erosion Faith is talking about, as far as I know. The eroded material became suspended in the active flood waters.
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3. As the flood waters quieted the previously eroded material began falling out of suspension to form all the sedimentary layers of the geological record, including the Grand Canyon Supergroup. Because material falling out of suspension doesn't explain the sorting of material into the homogenous sedimentary layers, more recently Faith has been placing greater emphasis on Walther's Law as being responsible for the sedimentary layers.
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4. Tectonic forces caused uplift of the Grand Canyon region, and they also tilted the layers of the Grand Canyon Supergroup and broke it into blocked sections.
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5. Receding flood waters eroded the sedimentary layers to form structures like the Grand Canyon.

Deciding what is and isn't on topic is the moderator's responsibility. Please let this moderator do his job.The message you're replying to was about the timespans represented by missing eroded material of the geologic record, including material eroded away at angular unconformities. This seems very relevant to the topic.Concerns about topic are better brought to the Report Discussion Problems Here 4.0 thread.

Perhaps I shouldn't have used the term "angular unconformity." I'm not sure.I felt that the Navajo Sandstone was on topic because it represents erosion of tilted layers, though in this case the tilting is due to cross-bedding and the material being eroded was not, in some cases, lithified. The principles are the same.

An angular unconformity is a perfect description of what is seen in the Navajo Sandstone as I pointed out back in Message 594.Repeating the image from that post and from the explanatory link in that post. If you look at that picture you will see horizontal bands of sand which truncate the crossbedded bands abruptly and is clear evidence of a period when the peaks of the lower dunes got eroded away and a layer of material (not showing cross bedding) was laid down followed by renewed dune building. In fact in the picture you can see several such interruptions where unknown amounts of already deposited material was eroded away.

Percy did a decent job of describing my Flood scenario in Message 625, but I thought I'd add my own restatement of it. Yes, erosion of ALL erodible sediments on land. By the pummeling of forty days and nights of rain, saturating the land, causing mudslides, mixing into the sea water which is starting to rise up on the land. There were no sedimentary rocks in this early phase of the Flood, if that's what you mean. What do you mean, "Correct?" I'm trying to describe what must have happened in the Flood.No, the GC Supergroup did not exist yet. It was laid down as strata in the next phase of the Flood. I'm talking about the earliest phase of the Flood, when NO sedimentary rocks yet existed. They were all laid down IN the FLood, including the Supergroup, as I even said in the post you are answering. The strata that later became the Great Unconformity did not yet exist. No, as you just quoted me saying, the strata of the Supergroup, "the lowest levels which later formed the Great Unconformity" are being laid down as strata by the rising Flood water. The unconformity did not yet exist because the strata of the Supergroup did not yet exist, are only now being laid down in this second phase of the Flood.This is all being laid down on what I called "bedrock" or whatever non-erodible surface remained after all the erodible sediments had been eroded off it and suspended in the Flood water, the sediments that are now beginning to deposit as strata. If "bedrock" is not the right word, please correct it. Indeed I do, though apparently you aren't getting it. Percy did a pretty good job of explaining it though, perhaps that will help. Not in the slightest.Edited by Faith, : No reason given.

There are just a couple of small points I'd like to correct in your otherwise good description of the Flood scenario: Yes. "Bedrock" is the only word I can think of to describe what must have been a surface that could not be eroded after everything above it that could be eroded had been eroded. If there is no such thing or another term is needed, please supply.I'd say "rising" Flood waters. This is the earliest phase of the Flood. Yes, "active" too I guess. It took five months for the Flood to rise to its ultimate height so it was climbing up onto the land fairly slowly. Yes. But this would have occurred while the water was rising, which is how I now understand Walther's Law works. Yes. Walther's Law offers an explanation that is becoming clearer lately. Yes. Yes.