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

NO, I agree. The sagging layers "hypothesis" is pretty silly.HBD

I don't believe your memory is correct here.You wrote that the sagging strata were drag folds. I then said that, if so, there should be some evidence of shearing. Your response has been, 'well, look at the drag folds!'. You have yet to show that they are drag folds...Anyway, how did this drag cause gravel to deposit out away from the basement along bedding planes?Please provide some kind of kinematic model showing shear planes and directions of motion. You said this:

quote:

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"I suppose it should be found somewhere in the Tapeats."

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Can you do that? So, rather than being at the surface and saturated with water, you want to have the Tapeats buried under two miles of sediment and still be a soft sediment. That is your scenario, remember: all tectonism occurred after all the rocks were deposited.And you still show no evidence for 'intrusion'. Other than the fact that you have not shown that any drag folds exist, how would that create the cross bedding that is depicted?You realize, of course, that your sense of motion is virtually indistinguishable from sediments compacting under gravitational forces.How about some physical evidence? It seems that you are doing a whole lot of 'guessing' here. How about a fault? Maybe some offset beds or dikes? Again, I do not see evidence for drag folding. It may exist, I just don't see it.The real problem for you comes when one tries to show the sense of motion along these shear plane that would move the gravel out into an apron-type of arrangement.Maybe you could draw in the shear planes and show the sense of motion along them that gives rise to these gravels. In the meantime, debris shedding from a topographic high explains things pretty well.In summary, I'm still waiting for evidence that supports your scenario.

The recent discussion about drag folds indicates that some participants may not be aware that drag folds are associated with faults. I thought a definition might be helpful, so just to help things along, here's a definition from About.com:

Not being there is kind of an obstacle, but a couple of observations might be made. I see the same 45 degree fracture set in that area as you. It appears to extend as far into the distance to the right as far as I can see. It does not seem to extend to the left, though there may be some vestiges in the upper left corner of the photograph.The overriding feature, however, is that bedding planes (nearly horizontal) can be trace the length of the outcrop with no offset. Indeed they may be warped slightly in the lower part of the outcrop, but that goes away immediately under the Potsdam Sandstone label.Part of the problem is that these rocks have been uplifted to their current position, in part due to glacial rebound. The geological history is more complex than Faith seems to think. Edited by edge, : No reason given.

Just to explain a little further, I annoted Percy's reference photo from About.com. Bedding planes are highlighted in magenta and the fault is highlighted in yellow. The sense of motion is upper block to the right (I forgot to draw an arrow...).Note two main things pertinent to this discussion:1. the fault surface is not 'straight and flat',
2. there is evidence for shearing (in this case, we would call it 'brecciation').Edited by edge, : No reason given.

If the gravels were stripped off by the uplift, they would have been pushed against the hill not stripped away from it. The gravel would have been pinched between the Tapeats and the Archean structure, not ripped away from it. Ok, but... there should be patterns on the opposite side that reflect that asymmetry. The opposite side should have distorted in the opposite way. The same kinds of patterns are found on image 'e' If those patterns were caused by asymmetrical lift, the tallest hill (image 'e') was lifted up and to the right but the hill furthest to the left was lifted up and to the left.In image 'b', the layers above the hills are undisturbed. How "asymmetrical" are you thinking?HBD

It's my eyes, macular degeneration, not the monitor. I simply included the bush with the disturbed rocks above it because it's also dark, but the rocks above it are the target, part of the disturbance at the point where the bend to the left occurs. If you can't see how the layers to the left sagged while soft, and the gaping contact lines couldn't have been caused by blasting, there's no further hope for this discussion. It's me against a passel of biased untrustworthy opponents.

This is all apparently a matter of vision of one sort or another. Not to be able to see the evidence that the layers sagged while soft rather than being deposited in that condition just puts you, and HBD, so beyond reason I might as well save my eyes and get out of this madhouse. Edited by Faith, : No reason given.

Funny, I wouldn't trust you as far as I could throw you -- though I WOULD enjoy throwing you a great distance -- with any of your wouldacoulda speculations about anything whatever.Edited by Faith, : No reason given.

Res ipsa loquitur.

No, it's your memory that's bad. I have never mentioned drag folds in relation to the road cut layers,. There are none there. They are very prominent in the McKee drawings, however, and that is what I was talking about.But what's the point. When communication has gone this far off the rails it's over.

I think you and Edge are both talking about this diagram: Because it's so easy to include an image in a message and entails almost no overhead, I encourage everyone to include images under discussion in every message.Edge can correct me if I have this wrong, but I believe he's saying that since you think you see drag folds in one or more of the diagrams in this image, and since drag folds are associated with faults, where do you see the faults that should be present if indeed there are drag folds.

Here's your version of the image: TAD, HBD and everyone else can see that to the left the lighter colored layers above your red line tilt downward, and to the right they are mostly level. The question concerns what you see in the diagram that leads you to believe that the layers were originally horizontal.Looking at this message and the next one, I'm going to help you save your eyes and your sanity by suspending you for a couple hours.

I don't know what trust has to do with anything... Rather than addressing my character, address the argument.If the mounded hill was pushing up into the layers of sandstone and gravels were being stripped off the hill, why would they be forced out away from the surface? Why would they not be pressed against the surface of the hill?If the gravels are settled between the layers, away from the hill, in a line that follows the upper surface of the layer... doesn't it make more sense that they fell off the hill and landed on an exposed surface and were then buried by the next layer?You claim the gravels as evidence of "drag folds" or uplift and deposition, but the logic of what that observation suggests is completely backwards. I didn't make a wouldacoulda speculation about anything.HBD

I'm sorry to hear that. It must be frustrating. I don't want to be flippant or insulting about a condition that is beyond your control, but I wonder at the wisdom of arguing so vehemently about what you see in a picture when you have such trouble seeing in the first place. How could you distinguish between uplift of the right side and "sagging" of the left side. How can you tell that is not a near-shore deposit that tapers off near the water's edge? How can you tell? There is no "gaping contact line." That's what I am talking about. You think you see that, but it's not there and instead of admitting that it could be an artifact of your vision problems, you call us "untrustworthy." There is NO gap between those layers, it is shadows cast by an uneven surface. What would go a long way to improving discussion is if you would just admit when your wrong and not blame us. There is no "gaping contact line."HBDEdited by herebedragons, : spelling