Talk:Andesite

Wrong Info

Andesite is a fine-grained, extrusive igneous rock with anhedral or euhedral crystals. It's an intermediate rock and it has a medium color. It occurs when lava or magma from an andesite volcano cools underground. It usually has 55 to 65% total silica content, along with plagioclase feldspar(andesine and oligoclase), pyroxene, amphibole and biotite mica.

OK. Whoever that was, wrong, wrong, wrong. How can it be an extrusive rock which cools underground? Really. Rolinator 05:14, 27 December 2005 (UTC)

It is an extrusive rock. It cools near the surface or at the surface (or somewhere where heat can escape relatively fast). This is why it is fine grained. 38.100.75.194 (talk) 15:11, 12 March 2010 (UTC)

Silliness

Don't know much about geology, but I have a feeling that this article has suffered from some juvenile sabotage:

The water and initial tylerisstupid slab melts rise into the mantle wedge... The following part looks odd, too, unless it is some technical code unfamiliar to me:

Ultimately, the resultant composition of andesite and intermediate magmas is the result of fractional crystallisation, assimilation, partial melting cbnvcnvcnnbvcnbvc and contaminaton by the subducted slab.

Panatomic (talk) 17:11, 30 December 2007 (UTC)

Fixed, thanks - Vsmith (talk) 20:52, 30 December 2007 (UTC)

Thin section photomicrograph

I'm pretty sure that the thin section in the article is in cross nicols and not in plane polarized light. 38.100.75.194 (talk) 15:14, 12 March 2010 (UTC)

Yes, "polarised light" means nothing -- it should say whether it's plane-polarised light or between crossed polars. The image itself has metadata specifying the latter, so I've changed it. --Furrfu (talk) 20:01, 21 March 2010 (UTC)