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

If I "wiggle" one way and then the other it's because you are trying to pin some kind of exactness on me that I DO NOT MEAN. I keep saying that and you continue to do it. I'm trying to be clear.I won't deal with Thin Air tomorrow either. His rude attitude is way too much on top of what I already have to contend with. I'd rather be suspended.

Please do not comment on your perception of the personal qualities of others. I'm not letting others do it to you, and I'm not going to allow you to do it to others. Pointing out contradictory positions is not rude. Please confine your discussion to the topic.

Well, I'm getting the impression that Jesus wants me to answer you (I am not claiming to write what He wants me to write, though I hope it's acceptable.) That's the way it seems to me: that the request is unreasonable and makes no sense. It seems like meaningless nitpicking. It's hard to see it any other way though I've been trying to answer as well as I can and nothing I say seems sufficient. Perhaps I made it clearer in my answer to Admin. Perhaps not; That's because the request seems meaningless and unnecessary and I still see it that way. Horizontal is horizontal, why the quibbling? I honestly do not get it, it honestly seems like some form of madness to keep going on about it. Bringing in the angle of repose is another thing that strikes me as meaningless. I'm simply trying to be honest.This whole line of inquiry hits me as bizarre.Look at how the Strata, the Stratigraphic Column, deposited in horizontal layers. I'm not talking some kind of strange perfection, I'm talking the horizontality that is VISIBLE everywhere in those layers. But it doesn't seem to matter how I try to explain it, it's never going to be enough, is it? I'll be accused of all kinds of things from trying to "wiggle" out of this that or the other or who knows what all. You have NO idea what a nightmare this absolutely meaningless inquisition is to me. Steno describes "fluid" sediments, not lumps. I have NO idea what point you are trying to make with your obvious remarks. I have no idea what degree of incline would have what effect and I do not see any relevance or importance to the question. None. What I generally suppose is that on any incline the sediments will spread out to form a horizontal surface, therefore being thinner/shallower at the higher part and thicker/deeper at the lower. At what degree of incline something else might happen I have NO idea and NO interest in the question. (ABE: I didn't need to add this sentence; the former statement is my position what would happen with FLUID sediments. Not dry sediments.) Best I can do, but probably not to your satisfaction.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

A brief digression here, hopefully to clarify some points made earlier in the thread.We often read where Faith writes that erosion cannot form straight and flat surfaces. This has become and article of faith, so to speak. As 'proof' she wants us to show such surfaces in the modern environment (as though she has just become a uniformitarian).In response, there have been numerous examples provided by several members showing erosional and depositional surfaces that are as 'straight and flat' as can be expected from nature.In order to clarify my points on this, I re-submit the following annotated picture from Point Arena in California. I attempt to show an example of a wave-cut terrace that has been uplifted above sea level (this is common along the west coast of North and South America, in fact, it was noticed by Darwin, IIRC). I have added a solid yellow line to show just how even this surface is when viewed from the same elevation as the terrace (as shown in this image).In order to satisfy Faith, I have chosen a location where the rocks are tilted on end to account for the possibility of a future angular unconformity if this surface were buried at some time in the future. I have drawn some orange accent lines to show the orientation of the original, horizontally deposited bedding in these sedimentary rocks. Is this clear to people?As a bonus, I have looked into the future and proposed that a new wave-cut bench is forming at the base of the cliffs at the surf line. In magenta, I show the base of the cliff and an arrow extending out into the surf where the rocks are being rather savagely beaten by waves. If allowed to continue for a long enough period of time, I contend that rocks above wave base will be planed off to form another wave cut bench below the one supporting the lighthouse in the picture. In other words, we are seeing a geological process in action ... erosion.One notable observation here is that erosion (and I'm not sure what else it could be) has truncated (cut off), at their upper end, the bedding planes shown in orange. By the principle of cross-cutting features, this means that the erosion is younger than the sedimentary layering. In fact, it is also younger than the tectonic event that caused the layers to become tilted.Now, Faith might say that this surface is caused by shearing (at least where it is straight and flat). However, I challenge that. What body of rock moved across the tilted sediments shown in the picture? That would be how shearing (faults) form: by moving one body of rock relative to an adjacent body of rock. So, where is it?And I'm not even going to get into the lack of evidence for shearing...Or, Faith may just say that she 'doesn't see it'. I hope that my highlighting and annotation help with this problem.However, I know almost to a certainty, that Faith will say that this surface is not 'straight and flat' ...... enough.I will point out that this could just possibly be a matter of opinion, ... or bias. However, I fail to see any examples of unconformities in the ancient record that are more even than this.Here is another example of a 'straight and flat' surface formed by continental glaciation in north Sweden. I'm not sure if everyone can see it or not, but I refer to the gently sloping surface at the base of the larger trees and above the dark gray, slaty rocks which are tilted toward us in the picture. It's like an ADA compliant sidewalk, and yet, 'not straight and flat' ... enough.Now, further to the point of this discussion, we have several mechanisms for forming straight and flat surfaces, which I have mentioned previously:1. wave-cut benches,
2. erosion to base level
3. erosion to a resistant layer
4. glacial planationSo, why do I mention these? Simple: they are supported mechanisms, in contrast to Faith's mechanism (as nearly as I can understand it): Never mind that we have not actually established that shearing actually happened.I apologize for being blunt and if I hurt someone's feelings, but these are facts and I cannot ignore reality.

I'll step in briefly to try to answer this: How far from horizontal a surface can be while still accumulating sediments is important because you said it is impossible for sediments to deposit on and next to rocks in any way that is not horizontal, and that therefore it is impossible that the sedimentary layers immediately atop this dropstone were deposited after the dropstone fell on a lake or sea bed: Another reason why how far from horizontal a surface can be while still accumulating sediments is important is that you said that layers like this could have not have been deposited in this way but that the Archean layer had to be intrusive, pushing the originally horizontal Tapeats layers upward and completely pinching out the lower Tapeats layers: But if layers can deposit when they're 5% and 10% and 15% away from horizontal then that would affect your position a great deal. This is why how far from horizontal a surface can be while still accumulating sediments is very important.Edited by Admin, : Improve image positioning.

Do you really, honestly, not understand the difference between a beach environment and the bottom of a body of water where there are no waves? You've seen snow drape over objects during a heavy snowfall on a calm day, right? Does the fact that snow doesn't drape smoothly over a mountain peak in a blizzard mean that those calm snowfalls don't happen?

Heh, heh, ... at first I thought you were showing us some gigantic dinosaur coprolites... They would, however be confined by the basin that they exist in so they would likely not flow (though I have seen it). One thing to remember is that the angle of repose in water would be less than in air because of the buoyant force of the water which would decrease the normal force of gravity (as you said, it's simple physics).The point is that the forces of cohesion, gravity, buoyancy, and internal friction all work to provide a degree of resistance to flow. I think that Faith believes unconsolidated sediments to have no strength at all, but even as it touches down, each grain starts forming some kind of relationships to other grains that create some strength. In fact with clays, they can start binding immediately because of their flat shape and unsatisfied bonds on their edges.The ultimate result of this process is a rock. Since the process is a continuum, we do not really create a distinction when referring to 'strata'. Otherwise, sedimentologists would be in endless debates about when a layer becomes a 'stratum' (sound familiar?).One interesting outgrowth of this phenomenon of angle of repose (kudos to whoever brought it up originally) is that eolian deposition should have a different angle from aqueous repose for the same material.Here is a demonstration of an eolian angle of repose from volcanic tephra alongside a highway in Iceland. You can see the natural angle as measured. You can also see departures from that angle where spires of volcanic rock intrudes the tephra along the skyline.An interesting effect is shown where the angle of repose has caused the debris to cross the road due to precipitation, freeze-thaw, etc., of the loose material. When cut back by excavation equipment, a new angle is established.I hope this is not too far off-topic, but I thought maybe some were not aware of the importance of the angle of repose. Certainly, cross-bedding in flowing water must adhere to this property of the material.

Yep. To someone who is knowledgeable of these relationships and understands them, it's rather simple to make reliable predictions. If one refuses to learn, guessing is all that's left. I don't know Faith's background, but I suspect she hasn't worked with materials very much. Grouts, mortars, concretes, etc. (hell, just a mixture of sand and water) 'gels' rather quickly achieving a measure of stability. Mix them up and they will again 'flow'. Let them sit for just a few minutes and they bind again. We're not talking 'curing', it's just the irregular shapes of the particles settling into interlocking positions with each other. When grouts are pumped into cracks or bores for soil stabilization, you have to get it moving and keep it moving or the process comes to a grinding halt.JB

As opposed to 'nit picking', it's fundamental to geological processes. When you tell us that sediment can only be laid down horizontal and yet we can repeatedly test the sedimentary process with a few simple tools and demonstrate you are wrong, it leads us to question your position. We can look at lakes and ponds world over where the sediment comes right up to the edge, rather than all settling to the lowest point. As a scuba diver, I can assure you that I've seen sediment drape over countless objects in a manner extremely consistent with the ways that Percy has tried to explain to you. As Capt. Stormfield points out, we can watch snow drape objects and follow contours repeatedly, and contrary to your assertions, snow falling through the air and contacting a surface behaves quite like sediment falling out of suspension in water - why?, because objects passing through air and water follow the same rather simple rules. You've avoided my simple questions in this regard like the plague, so I hardly see how you can honestly claim you've been trying to answer as well as you can. That's just nonsense in light of the retorts you have given those questions. Even your own answers are not consistent. One minute you are claiming that we are imputing some precision to you that you are not claiming, and then next you say "horizontal is horizontal". You can't have it both ways Faith. Either "horizontal" is perfection, or horizontal has variations based on the situation. You only see it as madness because if forces you to learn and to not make blanket statements. Once again, as opposed to "meaningless", angle of repose is of critical importance to geological processes. The angle of repose of a material in a given situation is repeatably testable and thus predictable and DIRECTLY related to the assertions you are making. The fact that it does strike you as meaningless means you need education before making any more assertions. As I've mentioned before, the "horizontality" that you describe is a function of scale. When looking for a far distance, it's easy to claim "just look at it ... it's HORIZONTAL". Problem is, zoom in and put your hands on it and suddenly it isn't perfectly horizontal any more. You're playing a fuzzy game until you want to play the in focus game. That's not the way science works. Oh, C'mon Faith. The term "fluid" as it's applied to sediment applies to a shovel full or a cubic yard or an acre foot. Fluidity is as property of the material and that property holds no matter the volume. The more viscous the sediment sludge, the less fluid it is. Every shovel of sediment in that picture has measurable fluid properties. There are even standardized ways of measuring these properties and frankly either learn about them so you can include them in your assertions or assume we will deem you willfully ignorant and treat you as such. That's not a rude statement, but a fair statement. Ok, I'll explain in greater detail: In the context of the sediment discussion, by "a high energy environment", I mean agitated water. Conversely, a "low energy environment" would be still water. In a still, deep, lake bottom environment, unless it's angle of repose is exceeded, sediment that is deposited at the high end of the lake has no means to move to the low end of the lake. Your assertion that all sediments will fill in at the low end is just bunk. There is simply no process by which it can pick itself up and move (thus the 'legs' comment).Better? So for the last umpteen pages, you have been directly making claims about things that you have "NO idea" about and "NO interest" in. See the problem?JB

Its because you've said that certain sedimentary layers could not have formed through sedimentation because they are not horizontal enough.That makes people question how horizontal you think something has to be before you could accept that it was the result of sedimentation.You have yet to tell us.

Faith, I still think that perhaps you are confusing the term "fluid" as used in the world of materials with the term "liquid". Several of us have provided links to show that these two are NOT the same, but your argument still seem to make it sound as though you haven't sorted this out. Solids, gasses and liquids can all have fluid properties and you have been provided with examples in all three categories.Particles suspended in liquid will indeed follow along with the behavior of the liquid. But once the energy becomes insufficient to maintain the suspension of the particles (in other words, gravity or other forces overcomes the agitation of the water and force the separation of the particle from the water), the particles settle and join other particles on the bottom.While the particles that have joined one another at the bottom as a group have certain fluid properties, they resists gravity's attempt to spread them out horizontally far more strenuously than does a thin liquid like water.In addition to the angle of repose which is testable and repeatable (and thus reliably predictable), materials specialists have developed other methods of measuring the fluid properties of sands, gravels, grouts, mortars and concretes (with the common gooey sediments being closest to grouts). One such is a "slump" test. You load a 'slump cone' (generally 12" tall) with the aggregate you are testing (wet or dry as required), strike off the top level and lift the cone up. The amount the material settles is called "slump". Some tests on more plastic materials might ask for measuring the slump at time intervals (say 15 seconds and again at 60 seconds) whereas materials like gravel will slump immediately and then no more no matter how long you wait. Some tests may ask you to tap or shake the material base which introduces energy into the test slug and may increase the slump. When you watch this slumping process, you are watching the fluid properties of the material in action.From a practical standpoint as it relates to your "draping" assertions on this thread, the greater the slump of the sediment, the less draping will occur. The more stiff, sticky and viscous the sediment, the lower the slump and the more draping that will occur.It's all testable and repeatable and done to death Faith. Standard physics apply. You can protest all you want that it has nothing to do with your assertions, but fact is it has EVERYTHING to do with your assertions and it's not that hard to follow as to why.JB

Angle of repose has been discussed to death here before. Coragyps sent me a kit so I can observe it myself with sand. I don't doubt what has been said about it so I don't expect to get any surprising results which is no doubt a big part of why I never got to the experiment.But in a discussion of horizontality and the horizontal formation of strata it seems like a red herring. I've only skimmed through the posts above, however, so I may have a different take when I read them more carefully. I doubt it but who knows.I do have to acknowledge that edge's wave-cut terrace is straight enough and level enough to qualify for the prize. I don't remember it from earlier but it should have won then. So it COULD have become the G.U. contact in those straight and level pictures. I have to concede that he did show an erosional surface that is that level and straight. I still don't think that's how the G.U. formed of course, but for now he's met the test and I concede that much.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

All that has been shown here of "draped" sediments is drawings of the layers of the Tapeats over lumpy rocks. No photos have been shown so all we have is descriptions. The Tapeats is shown in the drawings to be draped in recognizable layers. No amount of mere theory is going to show me that happened with fluid sediments at deposition. As the argument starting with the road cut picture went, I could expect something of the sort with FORMED-BUT-SOFT layers but not with loose sediments. So if you want to prove that the Tapeats layers draped UPON DEPOSITION, you need some photos of some kind.Edited by Faith, : No reason given.

As for "fluid" and "liquid" since the distinction has been made I don't forget it, but I should probably just use the term "liquid" when talking about the deposition of sediments as layers since that's what I have in mind.

Today, I found this diagram showing a location in China where there is a shear zone (a fault) between underlying crystalline basement and overlying Miocene sedimentary rocks.I'm wondering if this is what Faith has in mind as a possible shear explanation for the Great Unconformity. The problem is that virtually all of the deformation is in the overlying rocks rather than in the basement rocks. This is a common theme in the geological record. Typically, rocks underlying a fault are less disrupted (deformed), which does not compare to the Great Unconformity.First of all there is an obvious shear zone characterized by oriented minerals, rock fragments and a 'mylonitic fabric'.In this case the rocks are being compressed horizontally (from both left and right). When this happens, the rocks need to expand in some direction (I suppose they might shrink...) and the easiest way is upward to the surface, forming ... mountains (isn't it great when things come together?).Now, when the basement rocks are compressed, they likewise must go somewhere and, unless they are sliding into the mantle due to negative buouancy, the easiest direction is also up. Look at the body labeled 'metamorphic rocks'. They are clearly forced up and over the sedimentary cover, again along a shear zone.So, how does this comport with Faith's scenario where the metamorphic rocks are compressed (folded) but do not disturb the overlying sediments?Well, in places we might see some kind of detachment fault (a fault parallel to bedding planes), but it would show shear textures. The real problem arises when we ask where the rocks are going. Ultimately, they have to go up... to the surface, in fact.In every case of faults parallel to bedding planes, they 'daylight'. They somehow reach the surface, usually by cutting upward through the superstructure of sedimentary rocks as shown in the cross section. For the purposes of this discussion, I would really like to see this shear zone of Faith's cut upward through the Tapeats, Bright Angel, etc. formations....As a final point, what happens when the surface is irregular? You can perhaps imagine your car driving along on nice smooth pavement and suddenly hitting a curb or a hedge. In the case of a curb, the deformation will probably be confined to your car (the upper layer), in the case of the hedge, the car will suffer some damage but the hedge will be splattered all over the land surface, effectively as fragments in the overlying layer.I call this, for lack of a better term, a buttresssing effect. Irregular surfaces either do not like to suffer shearing or they get severely disrupted. That is why people use studded snow tires: the ice surface gets severely disrupted in stopping the car. Basically, the gross coefficient of friction is raised on the sliding surface and sliding is resisted.Where do we see this in the Grand Canyon?