....Subduction
           (...the Far Side of Ridge Spreading) 

This has probably been said before but it bears a stand-alone page repeat - if subduction were to occur, then the continents would never separate and there would be no Plate Tectonics.  Why?  Because as soon as the continents tried to separate (because of a spreading ridge developing between them - as in the Atlantic, say) that growth of ocean floor would be matched by destruction.  The continent immediately facing the ridge (the 'near' side) would push the embryonic growing oceanic lithosphere down so the continents would never separate.  In order for Plate Tectonics to work subduction has to operate somewhere on the other side of the continent being separated - the 'far' side. ..............................

 
In the current model, plate motion is driven by subduction, i.e., it is subduction that pulls apart the oceanic lithosphere and separates the continents that ride on top.

Subduction, which is only occurring around the Pacific rim not only pulls on the Pacific plate (and destroys it), but must pull on the rest of the world's plates to destroy the non-Pacific volume of ocean floor that's being created as well.  This is impossible on grounds of scale alone because the turned down section of the lithosphere is so short, only a few hundred kilometres, compared to the tens of thousands of areal kilometres it has to pull.  Besides, the subduction zone can only pull on the Pacific plate since it is separated from the others by spreading ridges.

It is even more impossible when we think of the thermal dynamics involved.  For the so-called "cold subducting slab" (which has already traversed half the Earth's surface without getting cold enough to sink) now finds itself (as a subducting slab) ( forced down by continental lithosphere) in a much hotter zone where it is (supposedly) generating enough friction to melt the crust and create the Fiery Ring of the Pacific.  Surely, being forced down and getting hot enough to convert to eclogite (so that it can get more dense and sink), ...it should just pop back up instead, ..being hot, .. like at the spreading ridge.

In fact as the tomography of 'flat subduction' now shows, this 'popping up' is in fact exactly what is supposed to happen in the case of India, Japan, North America, and South America, as career artists hop on the bandwagon with no regard for the disaster towards which Plate Tectonics is heading, because this means that classic subduction, the downgoing subduction that returns the mantle to the lithosphere, can no longer work; instead there is just diapir rise (at the ridges), with the continental crust being lifted bodily upwards around the zone of flat subduction, and skating about on the asthenosphere as well.  Which is virtually the morpho-kinetics of Earth expansion, tempered by rotation.

So, ..the destination towards which Plate Tectonics is headed is actually Earth Expansion?   Sure is.

Anyhow, we're decades away from that, so ... (back to Plate Tectonics) which is it?  The slab sinks because it is cold?... or sinks because it is hot?   Ocean floor pushed from the ridge? ..or ocean floor pulling back to the ridge?  Colliding plates building folds? ..or one lifting the other up with no folds?  Subduction and plate separation driven by a roiling mantle boil?  Or subduction and plate separation driven by a freezing chill from outer space?  ..And so on.   ..Contradictions at every turn.

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