243,516 members
3,456,261 photos

Alden's Fotothing

and share
your photos
our fantastic photo library
Friends.Make Friends
Join our community and have some fun
Photos 116 - 120 of 666
geology rock


Here's what I went to Jenner to see: eclogite. This rock type is what happens to basalt when you push it 30 kilometers down into the Earth and heat it up to around 400 C for a million years or so. It's quite rare at the Earth's surface, but a chunk of it a few hundred meters across popped up amid the rocky glop of the Franciscan subduction complex. The reddish grains are garnet and the blue groundmass is glaucophane.
More latest photos

Comments on this photo:

Jul 07 2005 11:40 GMT curves PRO
Heat and pressure can make for beauty
Jul 07 2005 18:26 GMT jef PRO
I have a 1-foot hunk of that stuff from that very beach.
Jul 07 2005 20:47 GMT alden PRO
That's the only place you can get it for a thousand miles in any direction.