Evolutionists, please answer this

don findlay wrote:

(Anyhow, ..still waiting for some grown-up to come with an explanation
how vertically dropping slabs can create **TWO** circumglobal mountain
belts on the planet - one extensional and the other compressional. The
current 'answer' (favoured by grown-ups) seems to be childishly
idiotic. No? Yes? If nobody is turning up to answer this one it can
only be because they're afraid they might get handcuffed to their
explanation. True grown-ups, indeed.


I wonder if Stuart, ...being a grown-up (when not blowing on his
alphabet soup to create convection cells that is), and into handcuffs
(literature ones I mean) ... has an explanation for this one. I mean
from a thermodynamic, 'energy' point of view....

What about it, Stu? Dropping slabs, ..or friction? Which? and
*TWO* mountain belts. What was it you said about the elegance of
convection and Plate Tectonics?


It looks like Stu's playing dumb on this one. Maybe somebody in
physics with a geological bent can explain this one to poor dumb
geologists over here - seeing as to how geology these days is dependent
on physics for its Plate Tectonics:- ... How can subducting slabs
(dropping vertically into the mantle or grinding down the underside of
the crust ('lithosphere')) generate enough energy from uniformly
distributed "corpuscles of heat-releasing radioactive elements in the
mantle":- http://users.indigo.net.au/don/ng/corpuscles.html
to make **TWO** mountain belts on the planet, ..1. the spreading ridges
on the ocean floors (which dwarf the regular ones for size and are
extensional), and 2. the regular ones in the continental crust which
are compressional?

From an energy perspective I mean, ..these cold chunks of ocean floor
which have moved for thousands of kilometres, and have lost all their
heat on the way, ...well not quite all since once they start to bend
down *THE ZONE* they release even more (to throw up these mountain
belts), ..I mean, how are we supposed to envisage this from an energy
perspective? And why the big hiatus in losing heat - represented by
the big flat bit between the slope off the ridges, and the subduction
zone?

Doesn't this mean (if we balance the compressional mountain belt with
the extensional one, and find the balance is with extension) that the
net effect is to keep making an *extensional* mountain belt and that
means the ridges (and the ocean floors) keep rising?


Also:-
_______________________________

http://scicolloq.gsfc.nasa.gov/Lowman.html
PAUL LOWMAN
GODDARD SPACE FLIGHT CENTER

"Space Exploration and Plate Tectonics"

The second half of the 20th century saw two historic scientific
developments: the achievment of space flight and the emergence of the
theory of plate tectonics. These superficially independent events are
much more closely related than most scientists realize. This lecture
will summarize major discoveries from space research, both terrestrial
and extraterrestrial, and demonstrate their relation to plate tectonic
theory. Examples will include sea-surface altimetry, direct
measurement of plate rigidity and plate motion, remote sensing of
continental areas, discovery of folded mountains on Venus (a planet
with no plates), and evidence that even small bodies like the Moon have
undergone early global differentiation, forming crusts analogous to the
continental crust of the Earth. Plate tectonic theory has been
essentially confirmed by space research, but it has also been found at
least incomplete, if not incorrect, in several respects.
____________________________________________

....And what does somebody from Goddard Space Centre mean when he says
that last bit about Plate Tectonics being incomplete? He's just said
it's a "historic achievement".

...And " *SEVERAL* respects"? Can anybody mention one? What's he
mean? What's he talking about?