Re: volcanic ashes

From: Robert Flory (wyogeo_at_bigfoot.com)
Date: 07/10/04 

Date: Fri, 9 Jul 2004 22:24:05 -0700

"Carsten Troelsgaard" <carsten.troelsgaard@mail.dk> wrote in message
news:40eaa620$0$249$edfadb0f@dread12.news.tele.dk...
>
> I'm achtually not all too sure on basaltic magmas. The chemical
composition
> may cause a much faster developement of small crystals, and it's not
unusual
> that crystals float in the magma. Anyway, this is not the airborne
> pyroclastics that you adress.
> I'm still not a specialist. Maybe you should hit googles until one shows
up.
>
> > Thanks,
> >
> > Frederiek
>
> You'r welcome,
>
When I used to live on the Snake River plains, the kids and I used to pick
up small pieces of basaltic glass. I've seen it in many pillow lavas. It
is a function of the rate of cooling.

http://www.uni-mainz.de/FB/Geo/mineralogie/petrologie/Burkhard/AachenPaper_free.pdf

even artificial http://www.albarrie.com/Filtration/fil-basalt.html

Bob