( .. and spells its demise .. )
(From lst edition, archives ~ May, 2008)
The so-called 'cold subducting slab' of the Western Pacific 'slides under' the continental lithosphere and terminates on the asthenosphere, i.e., it is *not* being returned to the deep mantle. No return to the deep mantle means that subduction (here, the type area of the mechanism) cannot be a driver for Plate Tectonics. " The sinking of vast sheets of oceanic lithosphere back into the mantle is the primary driving force of plate tectonics." |
Fig. 1. Seismic tomography beneath the Japan Trench. Showing 'FLAT' SUBDUCTION. No sinking here... The 'subducting slab' (blue/ cold) is simply being 'pushed' under the continental margin of Japan by so-called "ridge-push". [Vertical cross-section beneath Japan produced from GAP-P1. This is the same figure as Fig 2(a) in Obayashi et al., 2006.)
Plate Tectonics would probably say,
"Well of course, only a fool would think the cold descending slab sinks into the mantle the way we've been showing it for years and years and years. *THAT* angle is only the TOP of the going-down part in the upper mantle, ..you know, the lithosphere, ..the brittle bit where you get all the Earthquakes. Now we know that what *really* happens is that the slab gets pushed flatly under the continents just so far, by the force of ridge-push (..you know, that ten centimetres of dyke that gets intruded at the ridge every year? ...the one forcing the ocean floors apart and pushing it across half the world? ... yes, that one), then it snaps off and sinks (flatly) allowing the part just emplaced to be overridden by the next length of subducting slab. As it heats up it becomes less rigid (pale blue). We've been telling you all along about FLAT SUBDUCTION, haven't we? So, ..well, ... now it's clear that is what we're dealing with - flat subduction. We've known all along that the other subduction, the steep one, is really a bum steer. But this one's a little beauty - because we thought of it."
"But didn't you think of the other one too?"
"Well, ...Not me, ..I didn't think of it.."
.... So that in time we have a whole lot of them (slabs), all stacked neatly one on top of the other descending 'flatly' into the mantle. You see all those concentric, flatly orientated, pale-blue pixelated layers going right to the core-mantle boundary? Well, they're all piles of flat slabs, all heaped one on top of the other, going down, zig-zagging into the mantle, ..getting heated up as they go down, which is why they're paler blue. Not so brittle you see....
"But some of them are paler than others, and they're *above* darker blue ones. In fact the one right at the bottom is the darkest blue of the lot."
"Well obviously that's because it was even darker blue to begin with. You're obviously not getting what this science is about, are you."
"But it's even darker blue than the ones at the top. Well, the ones underneath the asthenosphere."
"Obviously you need to read a book."
That's what's good about Plate Tectonics, it can be bent any way at all. It's as bendable as whoever bending it is bent enough to be bent on making up bent explanations. It is no more than sheer invention - a bent invention unto whomever is bent takes it upon themselves to bend. ..
Rubber numbers.
But how did we ever get the picture of steep "subducting slabs" in the first place, when tomography shows them to be so obviously flat? Why? Because only ever shown was the broken lithospheric edge-effect down to about 600km, i.e., what happens at the edge between the continental lithosphere and the oceanic lithosphere, i.e., the upper mantle effect. Usually the bottom part is carefully trimmed off in case it spoils things. There was a story going around, you see ...about how subducting slabs drive Plate Tectonics via the deep mantle and convection, so only ever shown was the data to support it (the steep bit), .. looking like it was returning to the mantle.
Bent, you see?
But now, with the spin-related, concentric structure of the mantle (=>) becoming ever more obvious through mantle tomography, this concentric, non-descending structure of mantle slabs is becoming something of a celebrity.
[ Celeb Tectonics (may need quoted text shown) (Celebtonics.) ('Coz it looks good.)]
Of course, 'flat' slab subduction is a contradiction of the spirit of original agreement as to the meaning of the term, but what does that matter when there's a whole new gravy train of publication opportunity revving up, just waiting to leave the station?
All Plate Tectonics has to explain now is how the subducted slab (flat subducted or no) gets colder (bluer) as it goes down, as in the figure. And why the non-oceanic/ continental lithosphere is all hot on the landward side. Well, we could say that's easy, is it not? The friction of the slab going down and getting pushed along heats everything up and makes it rise, just like at the ridge, ...even melts it and gives volcanoes. But the slab of course must stay cold because it has to sink to drive everything, but there are surely research opportunities there too, to pad out this gravy train.
I wonder if this flat slab grinding away underneath the continents, melting everything and making it rise, rises with the rise too... Or does the slab stay cold while the friction it generates heats everything else up?
You can see from the figure it only gets cold when it meets a continental margin. If there were no continental lithosphere to force the mantle down (=>) there would be no convection and no Plate Tectonics. It wouldn't matter how hot the Earth was inside, with no continental lithosphere to push the mantle slabs down there would be no Plate Tectonics. (Got it?... the logic of the subducting slab against a continent? .... just by sitting there doing nothing the continental lithosphere is driving Plate
Tectonics.)
Now, ..that's the Western Pacific. It's the same in the Eastern Pacific where the Americas are overriding the Pacific plates. And it's the same under the Tonga trench. And it's the same for India, now that it's not India colliding with Asia and crumpling up the Himalayas, but the Himalayas that are being bodily uplifted by India being driven (flatly) underneath causing the collapse of the Himalayas southwards over the Indian Craton.
So with all this so-called "flat subduction" going on (a contradiction in terms if ever there was one) where's the subduction that returns stuff to the mantle to drive Plate Tectonics actually happening? (Hey, ..More research! Who said this Plate Tectonics stuff was boring?? Don't you just luv-vit?)
"Flat subduction" Googles about 2,860 (0.44 seconds) June 3rd, 2008
"Flat subduction" Googles about 7,840 (0.30 seconds) March 08, 2010.
Gee, this flat subduction is just crying out for research. That's more than thirty years ago since subduction (the genuine article) started. There's a wiki entry on the web too for just about everything to do with Plate Tectonics, but still no Wiki Entry for flat subduction (as at June, 2010). [seems to begin May, 2016 as 'Flat Slab Subduction' - I can hardly believe this!! df-20171004).] How come?
[ Addendum 20171005 :- Well, .. it could have something to do with my objection to Flat (/Slab) Subduction (along with a whole lot of others being compiled having been up on the web from about 2001/2 till this year (2017) when I had to change service providers because the one I'm with was not part of the National Broadband Network - up until which point (thanks to google) it enjoyed virtually top-of-the-web status for any rationally conjoined search terms to do with Plate Tectonics / Earth expansion, since which time there has been the most muscular effort from the academic community to reinforce the idea of flat subduction. But how can I know?. Academics are obviously the last people to put a reference to their nemesis. And the public don't much like their holy cows being painted black. Anyone thinking they can go against such a solid consensus as Plate Tectonics offers (and the hype that goes with it ; [1; 500,000 returns today)] [2]) without serious repercussions, is kidding themselves. [P.S. - Checking first link above, looks like it's been edited out too.]
The tomography depicting flat subduction is becoming more and more apparent, and has the potential to torpedo Plate Tectonics in its entirety. (=>) [see also.] Could this possibly be the reason nobody wants to deal with it (except here)? Subduction in its various guises is the central pillar of Plate Tectonics after all, .. and 'flat subduction' is its nemesis. [No convection = no Plate Tectonics.]
GeoFix apology for Plate Tectonics' subduction, .. from the University of Arizona:-
| "Plate tectonics, a theory which revolutionized our understanding of the earth. The theory however, failed to fully explain the formation of the Rocky Mountains, until the "flat subduction" model was developed. Dickinson and Snyder (1978) proposed that shallow-slab subduction could have transmitted tectonic stresses into the foreland and caused the Laramide-style block uplifts. Bird (1988) suggested that shear traction of the shallowly subducting plate stripped away the mantle lithosphere beneath the North American crust and transmitted shear stress capable of causing the foreland uplifts..." (http://www.geo.arizona.edu/geo5xx/geo527/Rockies/flatsub.html) |
"Flat subduction" ... Sounds good when it's backed with the www.*.edu respectability that's been paid for, but it's really another failed root'n-toot'n, shoot'n the foot'n goalpost shift... because if subduction is flat then there is no return to the deep mantle as there is with the conceptualised steep variety, which is the lynchpin of Plate Tectonics. Flat subduction is the overriding of gravitationally collapsing, equilibrating Pangaean crust ..of Earth expansion. As Hugo of the Benioff zone had it.
In Plate Tectonics the message is the concept, .. not the facts.
And they call this ("bending") science?? You gotta laugh! Some football! The biggest con-job in Earth science. But nobody wants to believe it.
Or are they just dumb? No. They are hamstrung by the sterility of consensus politics, .. by keep trying to position the goalposts according to the pressures of funding. And doing it without upsetting that $$$-applecart. How about for the price of a beer (/a couple of apples just about) together we can keep this thing on the road - (how simplicity trumps complexity) - and maintain some rage while we're at it, .. if you're bothered by the way experts keep bending the facts and leading people up the garden path by pulling dominoes out from off the bottom of the pack and deliberately putting them in the wrong order, so they can turn them around at will (or trying to do jigsaws without looking at the picture on the front of the box).
Fig.2. Flat subduction. The picture on the front of the box ["Lithospheric boudinage". 1 = continental lithosphere + collapsing edge; 2 = 'out-from-under mantle growth; + = earthquakes; 3= oceanic crust. (From Earth expansion 1st edition)]
=> (links)
