Thu 4 Aug, 2016 08:55 am - [quote]My wife took geology this past semester and she didn't have to use polarized light, let alone a petrographic scope, to identify any of the rock samples. [/quote]
Did she look at thin... (view)
Sat 30 Jul, 2016 05:16 pm - [quote]substage kighting would show pleiochroism in the biotite. none in amphiboles . Is the biotite/hornblende oriented or in a rock as phenocrysts?
oh yeh, also, how about isotope decay... (view)
Sat 30 Jul, 2016 05:13 pm - Well I was trying to help a fellow student with his homework. He was supposed to describe/ identify a mineral assemblage based on a simple picture of a Dacite in thin section (which I think is a... (view)
Fri 29 Jul, 2016 07:27 am - Hello everyone!
I have what might be a bit of a stupid question for the seasoned geologists/ petrologists (assuming there are any) on this forum: In a thin section, how do you distinguish... (view)
