Intraplate Magma Transport. The Concept Of Moving Transition Zone.

New concept of Plate proposed in the post "Plate Tectonics. Thinking Out Of The Sphere." immediately raises the question,  -  Is Transition Zone stable? What factors affect Transition Zone propagation? Can Transition Zone reach surface?

One of the specific features of the Transition Zone is that above it the solid body can respond with ruptures on the deformations, and below the Transition Zone the deformations can not cause ruptures. It was suggested that very this feature is responsible for magma propagation (see the post "Magma Transportation On The Temperature Gradient").

Now we are ready to think of Plate as a complex system of a) elastic solid body of very irregular shape and density b) viscous matter with very irregular viscosity/density/temperature/local_speed beneath/inside the solid body. If we accepted that plates are driven by divergent boundaries, then we don't need to group the semi-solidified/semi-molten matter beneath the plates into single wold-wide global class; we don't need to decouple the class from their solid hosts to invent the mechanism that drives plates.

Of course, the above is based on the "Magma Transportation On The Temperature Gradient" mechanism. The mechanism yet to be proved experimentally. The successful experiment would lead to relevant model of  Continental Formation and Evolution.

Quick search reveals that the closest in this direction were research works on shear-driven upwelling. Probably, if not limited by the paradigm of asthenosphere as separate world-wide layer, they could reach even further.

Plate being a complex system can develop deformations in its solid layer not only along lines, but also it could develop deep localized deformation induced by Moon/Sun. Such repetitive deformations can propagate Transition Zone up to the surface to form and feed a volcano.
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reposted from http://sukhotinsky.blogspot.com/
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