Re: Volcanic cooling - Physics anyone?

Arthur V. Chadwick (chadwicka@swac.edu)
Fri, 28 Feb 1997 17:02:53 -0800

Although this subject may have little or nothing to do with basaltic magmas,
any number of granitic batholiths have indications of granitization apparent
to the careful observer. For example the pluton upon which UC Riverside
sits on is well exposed behind the campus and displays well defined
sedimentary stratification. A few tens of miles further inland near Palm
Springs is a remarkable sandstone which grades laterally into a perfectly
good granite.
Although metasomatism, which was popular as an explanation of granites in
the 1940's and 50's, has largely fallen into disrepute, many competent
geologists still consider it the best explanation for such deposits. One of
the greatest draws for this explanation aside from the field relationships
was that it offered a solution to the "room problem", which remains one of
the great enigmas in geology. I have a couple of Russian papers (ok, so
they are russian...) depicting the relicts of fossils of molluscs and other
forms in granite.

If metasomatism is an acceptable explanation for a significant volume of
granite, this may impact the time problem with respect to cooling of
batholiths.
Art
http://chadwicka.swau.edu