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

From the standpoint of rocks being deformed by what I would call 'primary' conditons (occurring at deposition) yes. The problem is that a real dropstone situation has fewer variables such as the origin of the fragment within the ash flow, its pathway through the ash and the movement of the ash.Also, this type of deposition is subaerial.So, if we are talking about erosion, sedimentation, unconformities, etc., I think it much simpler to look at a simple dropstone system. Faith could have us running in circles trying to explain what's going on in the inside of an ash flow. That would be a logical interpretation. It would really be interesting to visit the location and see what other indicators there are. The annotated figure that I mentioned in my previous post showed cross-bedding in the ash flow with transport in the opposite direction. That could have been schematic or the boulder could have had a different velocity than the ash. Just too many questions for me to feel confident here. With only the photograph as evidence, yes. One thing to remember is that these flow can entrain boulders and 'float' them so that their immediate source is not the volcano itself, but from within the ash flow. Again, if you look at the 7th figure in the UMass lecture notes, you can see how they think volcanic rocks are transported in this type of flow.I just don't think that we can get into such details here. This is why geologists take field trips...Edited by edge, : No reason given.

Have you ever noticed the presence of cross-beds in the Coconino? How are those beds deposited at such an angle?And notice that nice, flat eriosional surface that truncates the cross-beds in this picture. But of course, erosion could never do such a thing... Or maybe you've read that the Coconino is highly variable in thickness, so how can it be perfectly horizontal?

I think this is an important point. No matter what definition of 'strata' you use, the sediments were all 'loose' when deposited, and they can obviously be deposited in non-horizontal fashion.So, when we see non-horizontal 'hard' strata (using Faith's criteria), we still have to describe the sagging rock structure.Faith has never given us evidence that this sagging structure is tectonic or otherwise related to intrusion (uplift) of a basement rock into the 'strata'.On the other hand, we have seen numerous cases of the sagging of loose sediments around a 'hard point' in the sequence of rocks.As far as I'm concerned, much of this discussion is really unnecessary. But perhaps some good has come from the discussion... I never thought of it this way, but it's a good observation.

I think Faith sees Steno's principles as a magic bullet she can use to refute the possibility that inclined bedding planes occurred at deposition. Remember, she wants all deformation, volcanism, etc., to have happened after the flood. Never mind that these are just principles and not immutable laws.I also think that among YECs, in general, there is a desire to accept authority. After all, their deity is the ultimate authority and he speaks through the Bible and the YEC interpretation. So, once you have an agreeable authority, he/she is revered.

Well, part of it. Do you understand what I'm saying when I explain that Steno's principles are just that: principles? Do you understand that a principle is not necessarily an immutable law? Do you understand that a principle depends upon definitions? Your personal attacks are getting tiresome. Is this all you've got?

Yes, this was Steno's understanding 350 years ago.Care to join us in this century with the knowledge that we have gained since then?

Please provide a reference to 'The Strata'. Gravel deposits are never continental, even in the geological record. What are you talking about? Ummm, most of the NA continent is above sea level, why would it be accumulating continental-scale sedimentary deposits? Gibberish. Are you saying that no sediments are accumulating on the bottom of the ocean? Who says there is a billion years of sediment on the ocean floor?As usual, you are making no sense. Please try again. As expected, Faith. Then perhaps you could enlighten us.Edited by edge, : No reason given.

Heh, I seriously doubt that. Yes, it appears that a hope is all you've got. According to whom?

I think I was running out of time last night and got to be a bit brief and perhaps a little short-tempered at the posts I'm responding to. Yes, I see what you mean. In some recent posts, Faith had started to provide an independent definition of 'strata' and to emphasize the point, she had started referring to it as 'The Strata'. I have no idea what this meant, but I suppose it conforms to her definition of 'real strata'. I wasn't in the mood to entertain further machinations. We have had plenty of those around here lately. Faith had mentioned these sedimentary deposits we were discussing are continental in scale. I was pointing out that comparing a gravel deposit to the Coconino (for instance) is not a good comparison. Here is the exchange: So, as you can see, I was uncertain as to what she meant. I intended to point out that yes, since most of the continents are very much emergent (above sea level), they are mostly undergoing erosion and continental-scale sedimentary deposits are not the norm.Here is what I said: Faith's next statement is a resurrection of an old argument of hers that the geological column stopped at the end of the flood. Basically, she is saying that sedimentary record has stopped. Our argument is that it has continued, just in a different place. This would be normal for geological processes.I think people have a hard time seeing long-slow processes and assume that the present is all that there is. And since all we see is erosion going on around us, that the world is fundamentally changed from the great sedimentary formations of the Phanerozoic. We don't see all of the sediments being deposited on the bottom of the ocean, and even the Mississippi River Delta is 'out of sight'.I refer to a later sentence of hers to show my point: In fact this may be true, but it is so for two geological reasons:1. The process of continental-scale deposits requires a long time and the slow process of transgressing/regressing seas, It was probably never visible.2. Continental-scale deposits require submerged continents.So, I responded with: Intending to mean that things are as I would expect them without modern, continental-scale deposits and that (as commonly occurs with YECs) there is no surprise here. In my very first geology class, this was one topic of discussion and I remember it well. Edited by edge, : No reason given.

Okay, that's the observation. Now you have left the realm of evidence and injected a personal wish. How long do you think it should be? I have explained the reason for this. I mean, isn't it pretty obvious that you cannot deposit a basal Cambrian (Tapeats, for instance) type of sandstone across the continent while the continent is above sea level?I'm not getting your problem here. Yes, that's what I said. The continents are above sea level. That is not reasonable. You don't know how many tectonic events there have been. Edited by edge, : No reason given.

I understand your frustration. It's really hard to debate on subjects where one is uninformed.But that can be fixed. It's a free world. Believe what you want. But if you come to a forum like this, expect to be questioned. Not if you look at all of the evidence. For instance, even at the height of the Cretaceous transgressions, there were emergent lands with volcanism and erosion in progress. I'm not sure why that should be a problem. Why do you term it a 'screeching halt'? Do you have some evidence that it happened quickly? My guess is that your only evidence is personal incredulity ... which isn't evidence. Actually, there was some. In the late Proterozoic, you had erosion of the GC metamorphic rocks (which had already been deformed and metamorphosed at least once; followed by deposition and then disruption of the GC Supergroup rocks; then more erosion followed by a long period of quiescence with a few erosional unconformities present. Then later, of course, you had uplift of the Colorado Plateau and downcutting of the Grand Canyon I've actually known this for a while. It is difficult to argue scientific points when you don't have evidence.

The problem is that we actually see those sagging, draping forms; so it's not a matter of whether they exist. The first two here, we have already seen from Namibia. The third one is from Washington state.

Well, yes, the land has to be covered by water. That is critical. However, the other critical point is that we develop laterally continuous deposits by transgressing and regressing of the oceans. Otherwise, you could not get the huge sheets of sediments covering areas the size of continents.Now, you can get regressive sequences, but they are a little harder to preserve since the exposed land surface can be eroded. However, they do happen. For instance going from the Hermit Shale to the Coconino Sandstone is regressive.

It's possible, I suppose; but there are other counterbalancing effect such as subsidence. As we load the crust, it will literally sink into the mantle.Rising sea levels, I think, are much more affected by melting ice caps and increased volcanism at the mid-ocean ridges.

This is correct that there have been multiple transgressions and regressions. In fact, during the Caboniferous there were many of them resulting in the stacked swampy deposits providing us with multiple coal layers. Look up 'cyclothems' sometime.However, the Tapeats --> Bright Angel --> Muav sequence in the GC is a classic transgressive sequence.When you think about it, it is easier to preserve from erosion sediments that have more sediment deposited on top of them. Since regressive sequences tend to leave more land exposed to erosion, they have a less chance of preservation. However it is still very common.On the other hand, erosion during transgression occurs mainly at the seashore where wave action destroys the land surface as the sea encroaches. However, the sand deposit representing a beach is then left behind and buried by more offshore sediments and then preserved. For instance, the Tapeats is mostly a beach sand and and slow transgression of the Tapeats sea caused it to be covered by the Bright Angel and then the Muav.I have drilled though a few of these things and I can tell you from experience that transgressive sands are generally thicker and more continuous than regressive sands.A great regressive sequence is the Hermit --> Coconino, as I mentioned before. There, we have a great erg (desert) encroaching across lowland swamps of the Hermit as sea level subsided.Keep in mind that these are the great cycles that we see in the geological record. There are many minor transgressive/regressive cycles throughout the record that give us things like stacked coal beds.