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Re: islands in the Pacific-was Re: mammal mystery
>Granites tend to be solidified stocks from which volcanos originated.
Not usually. Most granites rise within the earths crust but rarely break
the surface to form volcanoes. Gabbros are the larger-crystaled, plutonic
equivelent of the most abundant volcanoes, those that produce basalt.
Unfortunately there is a popular tendancy to call all large-grained igneous
rocks granites when the term should be restricted to only a few acidic
plutonic rocks. In the context of the thread, if your mountain is a true
granite, there is almost no chance at all of there being fossils because
the granite body would have solidified at a depth within the earth of
several miles. If fissues had been developed with in the granite that has
subsequently eroded out and were being filled with sediment, there is a
slim chance of fossils being found there. But we are drawing a really long
>If it is all granite - no. Granite almost never has fossils.
Could someone provide me with an example of a granite with a fossil in it?
Other than above-mentioned fissure fills, I fail to see how this coule
Dr Paul M.A. Willis
Consulting Vertebrate Palaeontologist
Quinkana Pty Ltd