I am norwegian doctor who worked as expedition doc on the Antarctic research station Troll for the summer season 2007-2008. NB: This blog is intended as a personal and ecological account from The Ice Planet - fully independent of the Norwegian Polar Institute, their official web page being: npweb.npolar.no

04 Dec 2007

Field trip

2 days ago, I got (yet another) chance to satisfy my science-fetishism.
As already mentioned, a 2-man BAS (British Antarctic Survey) expedition is being conducted in our "neighbourhood"; starting with the Jutulsessen nunatak area. The team comprises german geologist Horst and anglo-swedish(?) field guide Suna (well used to icy environments after overwintering at the british Halley station, a very remote station floating on a massive glacier). Basically, they're skidoo-ing around the wilderness, collecting representative rocks from different areas and trying to avoid crevasses on the way. The rocks will later provide endless months of lab work for Horst (radiometric dating, composition analysis, etc, etc), and finally, a couple of years down the line, he'll hopefully be able to cast light on the differing theories on crust formation. He's very enthusiastic about it, and after spending an afternoon sampling the local area with the two of them, me too. Geology looses (some of) its nerdiness when enjoyed in the field, armed with a big hammer.

Horst happily hammering away.

Fresh piece of granite intrusion dike. If that doesn't impress you, imagine steaming hot magma flooding cracks in the crust from below, deep deep down in the earth, under immense pressures. Heavy.

Suddenly back in touch with our feminine side, we stopped to enjoy this impressive garnet crystal, embedded in the granite matrix.

Migmatite. The most common rock in our area, called Gjelsvikfjella - part of the Fimbulheimen mountain range. Migmatite is a borderline rock type between magmatic (=igneous) and metamorphic. The layering is due to immense pressures and temperatures, causing partial melting. When the white lines (leucosomes) melt even more, and join up in big white continuus blocks, they're called granite, which qualifies fully to be called metamorphic. What's left (the black, harder bits) will then be called restite.

Big chunks of restite inside the granite. Geological hand-lens for scale. Baffin boot not meant to be included.

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