Formations really do match detailed lab expts of sorting under rapid currents

As pointed out by the creationist geologists S. Austin (Grand Canyon: A monument to Catastrophe, 1994) and G. Bertault (Experiments in Stratificaiton AIG video) the theories, obserations and experiments on stratificaiton by* J. Walther (on prograding coastal deposits),
* G. Berthault (J geol. Soc. France)
* P. Julien (Colorado State Univ)
* D. Rubin (Sed. Geology) &
* J. Suthend (Sed. Petrology)provide a far better explanation (than geological eras) of the formations anywhere in the world inlcuding those at Grand Canyon.The Tonto group in the Grand Canyon is about 1000 feet thick and is comprised from top to bottom:Muav limestone
Bright Angle Shale (clay)
Tapeats sandstoneThis formation covers 800 kilometres horizontally and in the current flow direction (that laid down these strata) each layer disappears one at a time in a prograding sequence. So you get these sub-formaitons side-by-side.It turns out that this exactly matches the types of prograding patterns one gets at a beach and what one gets in laboratory (warehouse actually) 'flume' experiments as discovered by the, mainly non-creationists presumably, researchers I cited above.What these people discovered is that under current one gets sorting by particle type and size and the layers are generated both vertically and horizontally at the same time. The lower layers at the end of the flow direction are formed after much of the top layers at the start of the flow area but the layers are trackable from start to end. Changes in flow velocity instigate new layers forming and sorting is partially ordered by frictional effects of whatever layer is currently immediately below the local flow.What this means is that when we see 300 foot of sandstone, 300 foot of shale and 300 foot of limestone we should immediately htink of these experiments, not sedimentation under zero flow. In the flow case one can automatically get sorted beds without having to argue that the source site of sediment has changed what it is yielding.In the experiments, and in a coastal prograding seqeunce, what one gets is sorting from a mixture. While this should not be too surprising what this means is the 1000 feet of the Tonto group at Grand Canyon can be explained in detail (see Austin, 1994) by deposition from a 0.5 to 2 metre/sec flow in a few days rather than 70 million years during the Cambrian period. Of course no-one has ever seen that sort of flow over 800 km for 3 days but straight forward extrapoloation from the flume experiments, as well as Rubin's data (see above), demonstrates that this is what one gets.The point is instead of arbitrary series of events over 70 million years the entire formaiton is explained by the same sort of sorting process that occurs at every beach and has been studied in detail in flumes.I can't emphasize enough that the three sub-beds of the 1000 foot thick Tonto group looks geometrically, and from a particle size, just like the facies one gets from currents in the lab or at a beach. It's just on a bigger scale. Mainstream geologists have to completely ignore the powerful mechanism of hydrological sorting to explain a 1000 foot bed with particle variation becasue it immediately reduces their 70 million years to a single catastrophe.I strongly recommend the A$10 or A$20 outlay for Berthault's video "Experiments in Stratification" from AIG (and Austin's Grand Canyon).Sedimentology had always been assumed to yield the principles of superposition but that is only true in near-zero flow.The best explantion of the beds anywhere in the world is catastrophic flow, each for days at a time, over vast areas. This is the Genesis flood folks.[This message has been edited by Tranquility Base, 12-05-2002]

You do a good job of condescension Wehappy and assume that just becasue we claim there are three sub-beds to the Tonto that it is as simple as that. And I've understood about transgressive sequences all year.You think that posting a 'just-so' paragraph on the Tapeats removes what we are saying? We're saying that the entire Tonto is one big prograding sequence, just like at a beach but 1000 foot thick. The 300 feet of sandstone, 300 feet of shale and 300 feet of limestone is the gross sorting that occurred.If I understand it correctly, your explanation instead requires millenia of sandstone, then millenia of shale and then millemnia of limestone, completely arbitarily. (EDIT: I have assumed that you guys would not apply the prograding sequence idea to the 3 components of a 1000 foot thick formaiton, but I may be wrong).[This message has been edited by Tranquility Base, 12-06-2002]

Good point Edge.What Julien's and Rubin's data givesis particle size/velocity sorting statistics. they didn't get limestone, correct. One still has to have the raw products (mixed together is fine) before sorting. So what was the source of the limestone? Obviously weathered shells etc but creationists also propose the precipitation of calicum from inorganic sources as well.Nevertheless the point is that the empirical data, carefully collected for particle size, velocities etc suggests that hydrological sorting is a perfect and natural explanation of such facies, as big as they are. The lower layers at the end of the flow would have been layed after much of the top layers at the start of the flow even though the layers track over the distance.My comment on the principle of superpositon is that because of the prograding issue we can't assume that all of a lower layer was laid before all of the upper layer. If we apply this to the Tonto then assumptions of 70 million year differences could be completely incorrect.[This message has been edited by Tranquility Base, 12-06-2002]

CoragypsSee my answer to Edge on calcium sources.

WehappyI actually understand the situation perfectly for prograding seqeunces at a beach and in the creaitonist interpretation of the Tonto.Are you really admitting that, although the strata within the Tonto facies are sperated by bedding planes (essentially by definition) that a particular stratum, or facies for that matter, was not laid down at a fixed geological time even though the startum, or at least groups of strata, can be tracked for hundreds of kilometres? So the 70 million years traversed by the Tonto is not really true? Are you saying that some of the Mauv limestone was laid before some of the Tapeat sandstone? I of course believe that but I can almost gaurentee you that your fellow geologists would put a near 70 million gap between those formations. You are clearly distancing yourself from the principle of superposition in this case and I applaude that.[This message has been edited by Tranquility Base, 12-06-2002]

CoragypsDo yuo get anything like 300 foot facies of stuff forming on top of 300 foot beds on top of 300 foot beds today? If that's the case then the idea of dating by stratigraphical level is pointless. In the case of the Tonto group the strata are supposedly seperated by about 70 million years.If your agreeing with us on the hydrological sorting mechanism that is great but I don't see that ackowledged by the stratigraphic dating guys.[This message has been edited by Tranquility Base, 12-06-2002]

MooseI am reading it, and I did read it, but I'm trying to see if you guys really believe that for 1000 foot beds with only three facies. This is clearly not stated in a stratigraphical dating context.So will anyone go on the record and agree specifically that some of the top of the Mauv limestone was laid at the same time as some of the bottom of the Tapeat sandstone? Do you realise that these strata would normally be dated about 70 million years apart? (I know you know that actually).PS - I had always thought that when you guys talked of a prograding seqeunce it was for tens of feet of sediment not a 1000 foot formaiton. Please stop assuming I don't understand this stuff. I do. And I may or may not be finding some inconsisteny. We'll see.[This message has been edited by Tranquility Base, 12-06-2002]

weyhappyYou show me where there are 1000 foot deep transgressive sequences with only three facies occurring anywhere today. Sorting that would occur on the scale required for the Tonto group is the Flood.[This message has been edited by Tranquility Base, 12-06-2002]

To all of my teachers hereI enjoy learning from you but what sort of teacher pretends that his student doesn't understand something he does?In the very first post of this thread I outlined what transgressive, prograding seqeunces are all about (I summarized it in plain English for the typical reader here):

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"in the current flow direction (that laid down these strata) each layer disappears one at a time in a prograding sequence. So you get these sub-formaitons side-by-side."

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"It turns out that this exactly matches the types of prograding patterns one gets at a beach and what one gets in laboratory"

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"under current one gets sorting by particle type and size and the layers are generated both vertically and horizontally at the same time."

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The lower layers at the end of the flow direction are formed after much of the top layers at the start of the flow area but the layers are trackable from start to end.

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That was my first post!Most of you are quite rude.I am perfectly aware that regressive seqeunces have been understood for a long time, at least as long as J. Walther of Walther's law (about 100 years ago) if not longer.But I have never, ever read that applied to an entire 1000 foot bed stratigraphically except by creationoists.And if that is the case then the only difference between us is that we would point out that 1000 vertical feet covering only 3 facies and the 800 kilometres traversing 3 prograding beds speaks of something much larger than a slow marine invasion. Austin estimates 0.5 to 2 metres/sec for about 3 days would generate the entire Tonto deposit. The vertical and horizontal scope is very different to your beaches.

EdgeAustin's reconstruction has 800 horizontal kms from Nevada to New Mexico being laid from west to east via advancing flood waters with mostly 0.5 to 2 m/s flow velocity (W to E). From west to east we have Muav limestone, Bright Angel shale, Tapeats sandstone and the Great Unconformity.It's fine with me if you think this stuff was laid via hydrodynamic sorting vertically at the same time as horizontally.

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Three beds? Three facies? Really, where do you get this stuff?

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I thought we were talking about the 1000 foot Tonto series with three facies: M limestone, BA shale, T sandstone. It is these three which form a transgressive seqeunce from Nevada to NM or are we talking past each other? I apologize about referring to these also as beds. I am unaware of the exact definition of a bed and tend to use it to mean a collection of strata. But I know what a facies and a stratum are technically. Feel free to educate me on the definition of a bed. Should I refer to the Tonto as a bed or a formaiton or either?[This message has been edited by Tranquility Base, 12-06-2002]

So, since none of this is controversial to anyone then it doesn't matter to any of you that what is normally given a 70 my age difference could have been partially ocurring at the same time? That represents about 13% of the Phanezoic geo-col from the Cambrian to the Quaternary. How can you guys ever date a fossil by its position in the Cambrian in that case?Anyway, if you're prepared to believe that 13% of the Phanezoic is partially overlapping then we will point out that at that sort of rate the pre-Cenozoic Phanezoic could have been formed in about 6 or 7 such episodes. The scale of depositon calls for flow rates that would have deposited it all in a matter of months.[This message has been edited by Tranquility Base, 12-07-2002]

^ But the fact that the three facies that make up the Tonto are about 300 feet thick each but look like a transgressive sequence belies the catastrophic scale. That is the point I am trying to make. The strata can be followed horizontally despite the fact that the age of a stratum traverses much of the age of the bed! In your case a single stratum ridiculously traverses much of 70 million years. It is so obvious that these huge beds were deposited rapidly.ah2gfwj sbswbng (my oldest son typed that and I'll leave it here for posterity)[This message has been edited by Tranquility Base, 12-07-2002]

^ Lots of rhetoric Wehappy.So no comment on the fact that the facies sorted hydrodynamically from each other are about 300 feet thick each? Nevertheless the 70 million year difference, 13% of the Phanezoic, just became overlapping.[This message has been edited by Tranquility Base, 12-07-2002]

Mark24The sorting happens at multiple resolutions. You get a global (ie large-scale) sorting over 800 km horizontally and 1000 vertical feet and a local stratum level effect as well. It's not a pefect sorting across the entire 1000 feet. There are imperfections and they get sorted locally.

EdgeWho is Nevins? It rings a bell from our previous chats. Did Austin publish creaitonist material as Nevin's at one point? I think we all know his real name is Austin and that is what he publishes under these days too.The effect that Berthault, Julien et al find empirically is anti-intuitive. You get course stuff downstream first becasue the bed builds up horizontally and vertically at the same time and under rapid flow the fine stuff isn't deposited at all until the flow rate has decreased. The key issue is flow rate changes as well as flow rate at all. I thought it would be as you said as well but this is not what is found in the flume studies done at Colorado State. The leading edge (furthest from the source area) is coarse.Calling the Mauv a formaiton is fine by definition but may be a misnomer for creationists if we believe that it was formed at the same time as the Bright Angel and Tapeats. As a layman geologists I would think that creaitonists would view anything formed simultaneously to be a formation and the sorting by material as facies no matter how big. Because in the past, and perhpas still, you guys have had such a bias with the law of superposition it wouldn't occur to yuo to call the Tonto a formaiton. For us it is becasue it all formed in one dynamic.Having said all that, I can't speak for the professional creationist geologists. I'm only a humble biophysicist.I am fully aware that a 300 foot facies is a simplification but in our view of how they formed, a useful one. I'm fully aware that these formaitons come and go horizontally and are quite complex. Tonguing etc does not make any of Austin's clacs pointless. As a physicists we can do all sort of calcualtions that get the correct ballpark result. A spherical horse travelling at 20 km/hr will take 4 hours to travel 80 km regardelss of the anatomical simplificaiton made. Austin's results will be ballpark correct as long as, within the resolution he is working, he hasn't made any blunders. There is no need to require higher resolution to work out the basic flow rates. Just use Rubin et als empirical charts.