Thursday, November 2, 2017

Subduction - the Convenient Assumption

 Plate Tectonics as Junk Science
   (... Begins by assuming the conclusion .. )

"If  the creation of new oceanic lithosphere at oceanic ridges were the only process operating, the Earth clearly would have increased in volume and surface area at a remarkable rate in the comparatively recent geologic past" . "...large scale expansion is extremely unlikely...."   "Thus, an important element of the  seafloor spreading hypothesis from the outset has been the assumption that oceanic lithosphere is being returned to the mantle landward of the deep ocean trenches."    F.J. Vine 1987.  Encyclopedia of Structural Geology and Plate Tectonics (Seyfert), p.712  (confirming subduction was, and still is, an assumption.  [In other words, an ocean equal in size to the one we see at the present day is assumed to have disappeared down that thick red line - which is an oblique projection and therefore much thinner in reality than shown.]

Fig.1. Subduction zone and spreading ridges :-  As the statements of the Fathers of Plate Tectonics (above and below) show, the heavier trace of earthquakes around the Pacific and the Alpine - Himalayan region are assumed to be the zones of  corollary destruction of the ocean floors partnering the spreading ridges (lighter red trace).  They are not.  Click here for the wysiwyg alternative view according to Earth expansion.   [Image courtesy of USGS.]

".. It is convenient, in the context of plate tectonics, to emphasise underthrusting (subduction) of one plate rather than overthrusting (overriding) of the other, although kinematically both are equivalent" John G. Dennis 1987. Encyclopedia of Structural Geology and Plate Tectonics (Seyfert), p.503 (emphasising convenience and underthrusting - exactly a decade later than [1] and [2])

And again :-

" ..The theory of plate tectonics is based on several assumptions, the most important of which are :-
  • New plate material is generated at ocean ridges, or constructive plate boundaries, by sea-floor spreading. 
  • The Earth's surface area is constant, therefore the generation of new plate material must be balanced by the destruction of plate material elsewhere at destructive plate boundaries. Such boundaries are marked by the presence of deep ocean trenches and volcanic island arcs in the oceans and, when continental lithosphere is involved, mountain chains. 
  • Plates are rigid and can transmit stress over long distances without internal deformation – relative motion between plates is accommodated only at plate boundaries."  (Link)  (March, 2010 => Nov.2017)

There it is - JUNK SCIENCE (!)  :-: assume your conclusion  before you even start looking. It's called the scientific method. Spin an idea off the top of your head and see if you can discover something or other to support it, and call it causation.

This matter of assumptions, ..highlights the difference in approach between Geophysics and Geology. Geophysicists are clever, and reckon with some paper and pencil they can figger it out, and don't worry too much about the geology; get the 'rithmetic rite and the facts are sure to follow. They have to make assumptions, usually at the top of the page ("Let this be that and that and that be this") so the arithmetic will work. And then they think they're smart (and pretty) when the conclusions equal the assumptions. Geologists on the other hand are pretty ugly (and dumb) and mostly wouldn't know how, and as well, knowing the relative sobriety imposed by outcrop, look askance at the scribbled eurekas shoved under their nose by jubilant geophysicists creaming themselves over their beautiful inventions (repeat links for [1]  [2]).

The top of the page:- Growth of the ocean floors uncompensated by subduction means that the Earth is getting bigger.   Plate tectonics says, "This is impossible because we can't figger out how this can possibly be". Therefore, since there is no known mechanism by which the ocean floors can grow to create (not less than) two thirds of the entire surface area of the Earth, Plate Tectonics simply says:- "So, we can dismiss the possibility. Out of hand. Instead we will assume that subduction occurs. That way we do not have to consider the possibility of something we know nothing about, and what we think we do know, remains intact. Besides, we can see subduction in the seismic tomography. It is well documented."

Fig.2. Circum-Pacific subduction zone. Showing the plethora of earthquakes encircling the hinge of Pangaean opening (Pacific / Indonesian / Himalayan and Mediterranean regions). Apart from the accompanying rubble of destruction, these epicentre plots on the map are literally the only physical evidence for subduction. (Image from USGS, July, 2010) (Any day of the week.)

And that, in a nutshell, is plate tectonics' position.  But can we see subduction?   Is it well documented?  The answer is no, ...we can't.   And it isn't.   What we can see (that is well documented) is a zone of earthquakes that releases about ten times as much energy around the Pacific rim as spreading ridges and transform faults combined, and that reaches down to about 760 - 800km, and whose relative first motions of displacement are in fact much more ambiguous than the 'carrying down' of subduction says, and many of which are as much (if not more) 'sideways' (along the zone) than down.  But plate tectonics assumes that these earthquakes (= brittle behaviour) mean that the zone of mantle in which they occur  (which they call a  'slab'/  'mantle slabs') is cold, and is therefore more dense,  and is therefore sinking.  So when Plate Tectonics uses the term "subducting cold mantle slabs" as shorthand for what it intends to convey, it is being highly misrepresentative of the facts.  It is in fact saying no more than "..a zone of Earthquakes that reaches down to 800km".  It can pontificate all it likes about the theory of "anomalous seismic zones"  (again in case you missed them [1]/[2]), but the palpable fact(s) is/are the distribution of the earthquakes

There are ways of interpreting that distribution (as described on this site)  other than Plate Tectonics says.    The mantle is not necessarily 'subducting', nor even  (as it supposedly 'descends') is it cold, .and the 'slab' (if described as such) is actually constituted of the entire ocean floor right back to the ridge, not simply the turned-down sector that Plate Tectonics chooses to label 'slab'.  If coldness and slabness is the point, why doesn't the entire ocean floor just sink?   It is after all cold and more dense than the mantle on which it is sitting. Why must it travel so far from the ridge before it is cold enough to sink?  It's pretty cold right where it is - on an Icelandic slope, say, ..even in the sunshine.  And why (if it is cold) must it always sink on a line (a continental margin)?  Why doesn't it just sink anyhow, a 'plate' - and zig-zag to the bottom of the mantle?  Because there is a space problem? room for all that ocean floor at the surface to sit on the much smaller curvature of the core-mantle boundary?  Or maybe, because gravitational force tapers off with depth it will tend not to sink at all after a while?

Nope, ..that's not it.  According to Plate Tectonics it's not cold (/dense) enough.  To become cold (/dense) enough it has to be pushed down into the hotter regions of the mantle where it can undergo a phase transition to its denser equivalent of eclogite.  THEN it can sink ("because it's cold" - "because it's dense").

What?  It has to sink into the hot mantle and soak up heat so it can become cold /dense enough to sink?  Yup!  That indeed is Plate Tectonics' logic.   And just in case we need another bit of logic in order to swallow that one we have to consider another bit of PT-ers' logic, ...that to get down there in the first place the slab has to be forced down.  How?  Well, the continental lithosphere at a 'plate boundary'.  What's that?  By the continental lithosphere that is lighter than ("floating on")  the asthenosphere, do I hear you ask?  Well, .. yes again.  That's more Plate Tectonic logic.  It goes on and on, this logic, .. a bottomless Christmas Stocking jamboree of Wonderland Possibilities to aid publication and career advancement.  Can there be any wonder it's considered the greatest thing since sliced bread? [The Gift that keeps on Giving.]

"The development of plate-tectonic theory certainly warrants a Nobel Prize," said Dr. Marcia McNutt, president-elect of the American Geophysical Union. "There is no doubt that it ranks as one of the top ten scientific accomplishments of the second half of the 20th Century."

What Ms. McNutt means here is for the way Plate Tectonic theory has unerringly served the career interest of decades of geologists - or more exactly, geophysicists. An alternative explanation and (given the setting) a far more likely one for these earthquakes (and the crustal brittleness of 'slab' they represent), is that they simply express a fast rate of deformation. Even mud when pulled quickly will fracture, so it seems rational to regard that the rapid application of stress to any normally ductile viscous (or brittle) material will respond (within reason) in a similarly brittle way. And if there is any doubt about the fast rate of deformation around the Pacific just consider the daily number of earthquakes going off around it (well, ..month, according to the image above; makes no difference on a geological time-scale). On the scale of geological time this is a *horrendously* fast rate. Even on a daily rate it is horrendously fast (how fast do your fingernails grow?) Anybody who thinks those earthquakes represent the build-up of stress over geological time just needs to ask anybody living around the Pacific, where Earthquakes are going off every day (just about), especially the Indonesians who live on the cusp of global hemispherical twist, the devastated battlefield of Pangaean crustal severance.

Simply from a conceptual viewpoint earthquakes in a zone that we know is deforming quickly is far more likely to be linked directly to rates of deformation, than they are to be linked (in a crust that gets hotter with depth) directly to coldness (with depth). Hot enough to give partial melting, but cold enough to cause sinking? I think not (!) What about you? Besides there is not one earthquake, and never has been in the time I have been looking at that map, on the cold ocean floor itself away from the ridges. They're all on the transform adjacent the ridges or on subduction zones - the hot parts. So what's all this about 'cold' - brittle stuff? Hot and fast (and brittle) is more like it.

The term "cold subducting slab" is therefore little more than meaningless pterospeak, no more than supposition, but most of all it is code to support consensus: "I speak the lingo. I am one of you."

To understand the extent to which this meaningless pterospeak dogma has permeated understanding of plate tectonics we can juxtapose the quotes at the top of the page with others of teaching institutions today, which supposedly carry authority in this matter of subduction - which as things stand today is the crux of the Earth Sciences. All consensus publications (there are no mainstream others) are written around this fundamentally wrong 'cold slabby' concept of plate tectonics. In them you can see the extent to which the assumption of subduction underpins the position of plate tectonics. There is nothing factual about it.

"The size of the Earth has not changed significantly during the past 600 million years, and very likely not since shortly after its formation 4.6 billion years ago. The Earth's unchanging size implies that the crust must be destroyed at about the same rate as it is being created." (link)
" If the Earth was not to be blown up like a balloon by the continual influx of new volcanic material at the ocean ridges, then old crust must be destroyed at the same rate where plates collide. The required balanced occurs when plates collide, and one plate is forced under the other to be consumed deep in the mantle." (link - originally :-: Now)
"Working together, the spreading and subduction processes make for a great global balance (the earth is really into balance and is good at it - it's been practicing for a very long time). New basaltic crust is produced at the spreading centers, and then consumed (or eaten, if you will) at the subduction zones, where it is purified and converted into granite. This is a real good thing, too! Without both processes the earth would either expand like a balloon (and pop?), or it would eventually eat itself into non-existence. Either result would cause problems for those of us destined to exist on its surface." (link)

"Either result would cause problems for those destined to exist..."?     Well, we can't possibly have that, can we (problems in science)?   That wouldn't do at all.  That is why the subduction myth, as it was originally formulated (top of page), and which has transformed what used to be a subject with a highly empirical quotient, into *Junk Science*,  is perpetuated.   It avoids problems in science.

Find more about "assumptions of Plate Tectonics" [1] [2]

Fig.3. The necessity for the 'convenient assumption' of subduction.. ..Is the need for the removal of a hypothetical Panthalassa to make way for the present ocean floors. If there were no Panthalassa (below the picture) the continents would never separate. An imaginary Panthlassa (that has been destroyed) (so we never see it) is necessary for subduction to work. . (Image courtesy of Nasa.)
Or you could animate it and make it look nice, but it still doesn't work. There needs to be a continent riding on the oceanic lithosphere (green) so continents can collide and build mountains, otherwise Plate Tectonics would never work. But continents sitting on top of oceanic lithosphere is a contradiction in terms since continents sit on continental lithosphere, not oceanic lithosphere. [See how dopey and contradictory (link) all this Plate Tectonic stuff is? Why would anybody want to learn it? (Why would anybody want to teach it?) (Classroom mayhem.. that's what they're asking for) (if students have any sense..)
Nothing wrong with the sea-floor spreading (making the Earth bigger), .. it's the subduction (making it smaller) turns it into the nonsense of Plate Tectonics.]

"..If (as seems certain)... the Earth is neither expanding nor contracting, the net rates of spreading and subduction over any great circle on the Earth must be equal, and the pattern of plates and late motion must adjust to keep this so." (link)

Contradictions ==== "If, .. (as seems certain... )" ... (Yes/but..) (Now/then)

Googling < Plate Tectonics Junk Science >  [prescient]

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