Catastrophic Plate Tectonics - Fact or Fiction?

Yeah, because we all saw how well gravity worked in Indonesia...BTW, you were being facetious, right?This message has been edited by roxrkool, 07-01-2005 02:23 PM

Hi Chiroptera!

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Indeed the mantle is not even ‘fastened’ to the lithosphere. If it was there would be no lithosphere-asthenosphere mechanical boundary.

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This part is not true. The boundary between the lithosphere and asthenosphere is a region where the composition and physical characteristics of the material changes over a relatively small distance. The lithosphere does not simply sit on top of the asthenosphere like a brick my sit atop my cement driveway.

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No, what I said was accurate. I did not imply that the lithosphere sits on top of the asthenosphere like a brick. The concept of the lithosphere is rather straightforward, however there is in fact confusion because the precise definition depends on the property being considered (in our case, mechanical differentiation). Geophysicists may refer to the thermal lithosphere (where the mantle and lithosphere are differentiated by the equation T_s + 0.9(T_m-T_s), where T_s is the surface temperature, T_m is mantle temperature.), elastic lithosphere (where mantle and lithosphere are differentiated by noticable flexural differences in response to surface loads; the elastic lithosphere is defined here as the portion that is sufficiently rigid that elastic stresses are not relaxed on time scales of 10^9 yr or more. Solid-state creep processes relax stresses in the lower, hotter portion of the lithosphere defined by other criteria [conventionally temperature--the thermal lithosphere]), and the mechanical lithosphere (where the mechanical lithosphere remains a coherent part of the plate and typically does not deform by more than 1% on time scales of 10^8 yr at typical mantle stress levels. Because deformation is determined by viscosity (and if deformation rate is normal), viscosity is in turn determined by temperature. Thus the base of the mechanical lithosphere is typically perscribed to be differentiated by a 1,400 K isotherm.)I referred to the mechanical boundary because you incorrectly stated that "The continents are fastened atop of a solid mantle".Also see: Schubert, G., Turcotte, D. L., and Olson, P.; Mantle Convection in the Earth and Planets. pp. 25-26.

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Perhaps this is true. I don't know. But we are not simply talking about deformation in a small localized region, but entire plates moving as a unit. I have some trouble conceptualizing how, if the mantle really did suddenly heat up to this level, and this did lead to the much more vigorous movements, why the convection patterns wouldn't become unstable enough to break into small cells, breaking the large plates into much smaller plates. But I am not a geophysicist; perhaps it is possible.

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That is partly what Baumgardner's 2D computational simulations were all about. Variations in temperature in the mantle are not on small scales but on the order of 1000's of km, hence loci of convection are on those scales. Undoubtedly there would be scattered plumes of rising hotter mantle rock and inverted plumes of sinking colder mantle (and lithospheric) rock, but 99% of mantle redistribution is going to be due to the large scale convection currents.

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That heat would be localized at the subduction zone. It would not be distributed very far through the mantle, and so could not contribute to this accelerated motion of the entire crustal plate.

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Baumgardner's simulations actually show that the first instability probably occured in a lower boundary layer in the lower mantle that goes unstable first and then causes the upper boundary layer to then go unstable and subduct. Baumgardners 2D simulations show the runaway deformation rate quickly spreading throughout the mantle and I am not aware of any inconsistencies that would let us conclude that this should not happen. The spreading of the runaway deformation rate is not just due to conduction of local heat, but I believe it is due to the high strain rate effecting and propogating through adjacent mantle rock, especially along the plane of convection currents (which as seen in the 2D simulations is passed on much faster than thermal conductivity would allow if it were just due to conductive heating).-Chris GroseThis message has been edited by TrueCreation, 07-01-2005 03:51 PM

His question was why didn't water just go in from one end of a continent and go off at the other end. My answer was gravity.As far as I know, the tsunami in Indonesia didn't go in one end of the island and and go off the other end. Sure, it went in quite a bit inland but it didn't go all the way in and cover everything.

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Why are you asking us questions about your own scenario? If we're mistaken to believe your scenario would result in much generated heat, then just say so. Since a non-CPT person opened the thread, there was no introduction to the specifics of the CPT scenario. Perhaps you'd like to provide one.

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Im just tring to keep deerbreh on his toes. Im not going to let him get away with throwing his onus on me. I would be HAPPY to explain to him whatever he would like me to explain. However, for instance in the following case:

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As I see it, CPT has two main problems. First is a coherent mechanism. Baumgardner has proposed "runaway subduction". Frankly, I don't know enough geology/physics to know if this is possible but it does appear that for CPT to occur this would have had to happen. So the physics of runaway subduction is a useful line of inquiry.

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How can you present this as a problem if you do not understand it sufficiently to do so? I agree the geophysics of runaway subduction is directly relevant to CPT

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If he admits that he really didn't have any objectively definable reason to say this was a 'problem', and that his argument is mere speculation and conjecture, I would be happy to explain further in good heart. The point is I don't have to--the onus is not on me to refute assertions based on conjecture.

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I think this is the heat Deerbreh was referring to. The problem is, when you have titantic masses moving about rapidly, titanic energies are involved. You've got quite a heat problem.

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well do I? How much heat do I have over-budget? First tell me why the heat is problematic and then we can proceed to point out the solution to it.

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Not to mention that the oceanic crust is less dense than the mantle you have it falling into. This would never happen. Subduction only occurs because the oceanic crust, being more dense than continental crust, is forced beneath it and down into the mantle where it eventually becomes part of the mantle.

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Um, ok, no this is not accurate. The oceanic lithosphere has a material composition that at equal temperature is less dense than mantle rock, but the lithosphere is colder than mantle rock by over 1000 K and this results in a higher actual density. Subduction is not only a result of collision with continents whose crust is less dense than oceanic crust. It always has a higher density than underlying mantle. The reason it doesn't just subduct somewhere else is because the lithosphere is a rigid platform. The gravitational forces due to negative buoyancy would have to exceed its elastic strength. Yes collision with less dense continents cause subduction because it causes the plate to flex and bend toward the mantle, but the ocean plate does not try to bouey underneat the continents--it has negative buoyancy relative to the mantle and so continues to slide into the mantle. Have you heard of the tectonic force of slab pull?

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What caused the continents to suddenly begin moving at a rate of 10's of miles per day?

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The initiation of runaway subduction is debatable. Baumgardner has shown that the runaway instability can occur on its own on a timescale of about 10^7 yr, which I have no problem with (I am sure the earth is far older than 10ky anyways) or other possible situations have been suggested such as a small slab of oceanic lithosphere breaking off and subducting without the drag of the previously attached plate. I am sure numerous other geodynamic perturbations can be hypothesized as well. Accelerated decay has also been suggested.

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Where did the energy come from to accelerate the continents?

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Runaway rates of mantle convection, I presume.

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Where did the energy from decelerating continents go?

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Into underlying mantle, plate flexure and continental strain rates which may have subsequently rebounded or caused orogenesis, adjacent ocean lithosphere--it may depend on the geologic setting.

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Why, if the sea floor was recently created, does it instead appear young at oceanic ridges and ancient opposite them

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Because older seafloor was exposed and involved with more of the duration of the CPT event.

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Why is CPT inconsistent with radiometric dating?

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Is it?

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Why is CPT inconsistent with magnetic reversal data?

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It certainly isn't inconsistent. I would like to see you explain this one especially.

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What about all the earthquakes and tidal waves such huge movements of the earth would have caused?

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There may have been some tsunamis (I don't know if "tidal" waves would have been a huge problem, I doubt whether the "entire" earth's surface was completely covered at all during the event due to mountain building) I have not considered tsunamis to very significant depth. However I have considered seismicity. The dramatic weakening occuring at the slip zone at the cold top of the subducting lithosphere may allow for smooth sliding of the ocean lithosphere into the mantle without much high intensity stick-slip seismicity. I think this would directly effect earthquake intensity and frequency. However even if the the dramatic weakening was not sufficient and frictional heating occured, high intensity seismicity should still not occur. The high temperatures (and local melting due to the hydrated crust) at the slip fault would act as a kind of nonviscous lubricant. Furthermore this would also imply a boundary limit for high temperatures (because the rate of heating would decrease as the volume of melt increased providing a slip plane and decreasing friction), so heating as a result of the plate contact would be minimal.This would effect not only earthquake intensity and frequency during runaway subduction at the slip boundary, but will also allow for significant island-arc volcanism near subduction zones as is seen.-Chris GroseThis message has been edited by TrueCreation, 07-01-2005 03:47 PMThis message has been edited by TrueCreation, 07-01-2005 03:56 PM

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"...research [is] a strenuous and devoted attempt to force nature into the conceptual boxes supplied by professional education. Simultaneously, we shall wonder whether research could proceed without such boxes, whatever the element of arbitrariness in their historic origins and, occasionally, in their subsequent development." Kuhn, T. S.; The Structure of Scientific Revolutions, pp. 5, 1996.

"In all of that time, Baumgardner has never, to my knowledge, published a coherent explanation of how CPT could have occured in a peer reviewed scientific journal (as opposed to creationist publications)."Please understand why Hydroplate and CPT theories seem "improbable" from being published in Leading Science Journals, as per Walt Brown(In the Beginning: Compelling Evidence for Creation and the Flood - Misleading Statements).

Oh please, if the Baumgardner had science backing his theories, they would be published. No question about it.

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Oh please, if the Baumgardner had science backing his theories, they would be published. No question about it.

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No. But if Baumgardner had all science backing his theories, they would be published. The problem is that an underdeveloped theory that basically flies in the face of a paradigm that has held the general consensus and has been used as a basis of research by hundreds of thousands of scientists for well over 100 years, is not exactly considerable without considerable weight in its favor. CPT is not nearly as outrageous as other theories that attempt to shift the paradigm of uniformitarian geology, but it is not nearly consummately coherent. It would not be wise for Baumgardner to even attempt to publish his findings and he knows this.-Chris Grose

Is that what the model predicts? Tens of miles per day plate movement?If so Chris, have you looked at ophiolite complexes much? Wouldn't you think that at that rate, we'd see evidence for higher pressures in ophiolite complexes? We know the pressures and temperatures at which minerals exist and those found in ophiolite complexes point to very specific temperatures and pressures, which are consistent with mainstream plate movement rates.Mineralogic study is a powerful tool in geology and one which, when utilized, does not support YECism.Additionally, at that rate, wouldn't we see more complex and more numerous thrust faulting and related structures at collision zones than we do?I'm not so very interested in the physics of the earth or their related models (math bores me to tears), but I can tell you that no matter what the models say is possible, CPT must still be able to explain in a rational and reasonable manner what exists on the surface of the planet. Rocks and structures and mineralogy are the reality - not the models.So what I would like to know is what on the surface of the planet is evidence for CPT?

I would think that CPT as a theoretical possibility ought to be publishable - provided it can be shown that it really is a possibility. There's no need to get into the idea that it actually has happened.And once the idea is out there then maybe there will be enough interest from mainstream scientists that some of them might contribute to working out what the effects would be.

Chris, geologists LOVE to argue. That's what we do best.. besides brew and drink beer. (NOT till we're 21 though!! LOL)Baumgardner needs to first present his theories to the scientific community before he gets that backing. No serious scientist is going to back him just because. If it worked like that, we'd still be arguing if basalt precipitated from marine water. Baumgardner has had 20 years(?) to work on his theory and still has not presented it to the scientific community - that's enough reason to ignore CPT.If a geologist thought he/she had enough data to overturn even the most important paradigm in geology, they would do it and it would get published. And what a marvelous time we would have debating and discussing it. Geologists are well aware that innovative thinking often results controversy and this is what makes geology so exciting.

Do you believe that Noah was alive millions of years ago?Are you saying that the Genesis Flood took place over the course of tens of millions of years?

Heck if I know. My recollection is that both TB and TC used to believe this. I don't know if TC has changed his views on this, but he might have. TB says he has changed his views, but just as per his last visit, he remains a paragon of lack of specificity.--Percy

I thought I remembered TB recently saying something about the continents moving several miles per year. However, he didn't specify where that number came from.

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The initiation of runaway subduction is debatable. Baumgardner has shown that the runaway instability can occur on its own on a timescale of about 10^7 yr, which I have no problem with (I am sure the earth is far older than 10ky anyways)

Do you believe that Noah was alive millions of years ago?
Are you saying that the Genesis Flood took place over the course of tens of millions of years?

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No, I am saying that it would take several million years for the runaway instability that initiated CPT to develop. I have held the view that the earth must be at least significantly older than 10ky (albeit, maybe not quite as old as 4.6 Gy) since I began studying the general distribution of elements in the earth--The amount of fractionation and redistribution of elements the earth has gone through demands quite a bit of time. But that is another subject.-Chris GroseThis message has been edited by TrueCreation, 07-01-2005 05:53 PM

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"...research [is] a strenuous and devoted attempt to force nature into the conceptual boxes supplied by professional education. Simultaneously, we shall wonder whether research could proceed without such boxes, whatever the element of arbitrariness in their historic origins and, occasionally, in their subsequent development." Kuhn, T. S.; The Structure of Scientific Revolutions, pp. 5, 1996.

Thought of something else.In addition to ophiolite complexes and such, another thing we can examine are the magma and rocks at spreading centers. In order to maintain CPT for... how many years???... don't we need to see production of lithosphere/rock at spreading centers at the same rate as destruction of lithospher/rock at subduction zones?And if so, shouldn't see textural and mineralogical evidence for rapid intrusion/extrusion and cooling of the igneous rocks at spreading centers?And wouldn't this rapid intrusion/extrusion of magma result in increased global ocean temperatures?