Tuesday, June 2, 2009

Been A While : P

I suppose I should resurrect this thing!

What I've been doing since the last update:
-Research
-Finishing up classes and attempting to keep my head above the proverbial waterline
-Research
-A couple of small, random band functions
-Research
-Final exams
-Research
-Moving out
-Research
-Graduating
-Research
-More moving out
-MORE research
-Commuting between GB and EL to tie up the big loose ends in my research, create my AGU poster, a vector map of my study area, and find what is apparently the ONE garnet in all of my thin section samples.
-Sleeping
-AGU
-Photomicrographs and petrography and discussion of metasomatism, oh my. Woo.
-Caffeine detox
-Pathetic attempts at packing

And tomorrow: MOVING to Champaign! This should be interesting.

Here's what a photomicrograph looks like, for the curious:

The scale bar is 100 micrometers long, and this is a shot of zircons embedded in alkali feldspar, quartz, and suspected "amphibole" (we're not sure yet; might specifically be actinolite) crystals. The zircons are the small, brightly-colored, semi-rectangular crystals. The "amphiboles" are the green/brown, furry-looking crystals; the alkali feldspars are the black-and-white crystals with the jagged lineations; and the quartz is the amorphous white stuff. There's a strange reaction rim around the zircons embedded in the amphibole that we need to look at a bit more, so don't ask me about that.

Seeing those in the thin sections means that we can extract zircons from the kilogram of aplite I have crushed up and sitting in a bag, once we process the sample a bit more. With the extracted zircons, we can mount them on a disc and zap 'em with a laser, creating a small cloud of melted zircon, containing such elements as Zr, U, Th, Pb, and Si, among other things. The relative proportions of the radioactive/radiogenic elements will allow us to extract an approximate age from the zircons that is hopefully representative of the age of crystallization of the rock.

Cool stuff. This is what I'm doing with my summer vacation - exactly what I was doing during the year, without the whole going to class business.

1 comment:

Anonymous said...

Welcome Back! Good to see a new post.
If you close one eye and squint fancifully at the picture you can see a dog. The central zircon is his left ear, and the one with the darker red cast is his mouth. White chest and brindled back.

--pooh