Another thing about rapid tectonics is that most of the displacements we see on just about all faults, active or inactive, have to have occurred in a short period. Of course tremendous frictional heat is generated, but we old earthers have time to dissipate it. If the crustal movements evident in the geologic record occurred in a short time you would expect widespread frictional melting, which is actually quite rare in the geological record.
I was reading a paper in Geology a while ago (I don't have it in front of me) on frictional melting. It mainly occurs in environments where large masses of rock are relatively unrestrained, notably at the bases of mega-landslides and in the rapid isostatic re-adjustments immediately following large impacts. In most conventional faulting the rock masses are "pinned" at the ends and can't move rapidly. But in the aforementioned environments large displacements can occur rapidly generating enough heat to melt rock at the surface of movement.
Brent
--- "bivalve" <bivalve@mail.davidson.alumlink.com>
> wrote:
>The earthquakes caused by rapid tectonics would have been rather disruptive, too. Geology just had an article on the Chicxulub impact causing large-scale collapse of the continental margin of eastern North America. If a single major asteroid impact can do that, the effects of continents hitting each other at about 75 km per hour need to be accounted for to make the model credible.
>
> Dr. David Campbell
> "Old Seashells"
> Biology Department
> Saint Mary's College of Maryland
> 18952 E. Fisher Road
> St. Mary's City, MD 20686-3001 USA
> dcampbell@osprey.smcm.edu, 301 862-0372 Fax: 301 862-0996
>"Mollusks murmured 'Morning!'. And salmon chanted 'Evening!'."-Frank Muir, Oh My Word!
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