lucek wrote:Um yes it does. But given PT is driven by convection of the mantle I don't see how this supports you're case in the slightest.
You do not see why, because your conception of PT is at least 20 years old. You should read that review by Stern:
RJ Stern Subduction initiation: spontaneous and induced, Earth and Planetary Science Letters 226 (2004) 275–292I quote Stern:
"Earth is a spectacularly unusual planet and one of its most remarkable features is the plate tectonic system. Missions to other planets reveal that ours is the only planet in the solar system with subduction zones and plate tectonics [1]. The unique nature of plate tectonics on Earth is equivalent to saying that only Earth has subduction zones [2]. In spite of this singularity, there are fundamental misconceptions that concern aspects of plate tectonics and mantle con- vection. Not only are these wrong, they are deeply embedded prejudices of many earth scientists that continue to be taught to students. The most important misconception is that mantle convection moves the lithosphere (see dJargon BoxT), dragging the plates as it moves. This is repeatedly shown in introductory textbooks. In fact, Earth’s mantle convects mostly because cold lithosphere sinks at subduction zones [3] with mantle plumes representing a d. . .clearly resolved but secondary mode of mantle convectionT ([4], p. 159)."
then:
"There is a consensus among geodynamicists that the sinking of cold, gravitationally unstable litho- sphere drives the plates and indirectly causes mantle to well up beneath mid-ocean ridges. Some estimate that 90% of the force needed to drive the plates comes from the sinking of lithosphere in subduction zones, with another 10% coming from ridge push [11]."
So according to Stern, subduction is the driving force.
The problem is that others like Doglioni, completely refute it using well supported arguments. Read this paper:
C. Doglioni, M. Cuffaro and E. Carminati (2006) What moves slabs? Bollettino di Geofisica Teorica ed Applicata Vol. 47, n.3, September 2006 pp. 227-247And now, there is no more consensus about what drives plate tectonics at the point that top geodynamists like Doglioni explore some old hypothesis. Read this paper:
Federica Riguzzi Giuliano Panza, Peter Varga, Carlo Doglioni (2010) Can Earth's rotation and tidal despinning drive plate tectonics? Tectonophysics Vol484, Issue 1-4, pages 60-73But the answer is quite clear from some recent analysis of the anatolia/aegean sea region. The displacement of the lithosphere is mantle driven. Read this paper:
Le Pichon & Kreemer (2010) The Miocene-to-Present Kinematic Evolution of the Eastern Mediterranean and Middle East and Its Implications for Dynamics. Earth and Planetary Sciences Volume 38, pp. 323-351So the lithosphere does not move in blocks, but it follows mantle currents. This has fundamental implications, especially in the case of Wadati Benioff zone which become the front of mantle flows. This clearly limits the maximum surface of recycled lithosphere
as I explained earlier
in this post.
I'll let you some time to digest these papers and concepts and we can continue this discussion later.
In the field of observation, chance favors only the prepared mind. Louis Pasteur.