onsdag 1. juli 2015

Where on Google Earth #495

I found Gord's WoGE #494 quite quickly, a very interesting location in Argentina with sufficient visible clues to make it a relatively simple search.

My summer vacation starts in 3 hours, so I don't really have the time to search for a "perfect" WoGE this time. With the new update, Google Earth itself has a lot of interesting geography highlighted, which makes it a little bit harder to find something that will take at least a few hours to find.

This one shouldn't be hard to find, I believe.

But there is a LOT of geology here - metamorphic, economical, structural, glacial, morphological, erosional...

Previous WoGEs are collected by Felix on his blog and a KML file.

5 kommentarer:

  1. 69.4173 N, 17.1928 E

    Here we have fjords on the west coast of Norway, and the glacial influence on the landscape is pronounced.

    I'm having a bit of a tough time finding descriptions of this area in English, but here's what I've pieced together: during the Paleozoic, Laurentia (North America and Greenland) collided with Baltica (Scandinavia and the Baltic region) in the Caledonian Orogeny. This orogeny caused deformation and metamorphism in the region. During the breakup of Pangaea, there was extension in this region, and rifting further to the west. Erosion brought the Caledonides low, creating a peneplain. Subsequent uplift and glaciation caused the higher relief of the mountains and the fjords seen today.

    See https://en.wikipedia.org/wiki/Caledonian_Orogeny and https://en.wikipedia.org/wiki/Scandinavian_mountains

  2. This precise area is better described than most of this island, since there is a rather unusual mine here.

  3. Okay, after a longer search, I've managed to find a bit more (esp. this: http://www.ngu.no/FileArchive/BVrapporter/BV4194.pdf)

    There was a nickel mine near Hamn, which was mined from 1872 to 1886, mining pyrrhotite and pentlandite from a gabbro body surrounded by gneiss. In places the gneiss is more similar to a migmatite than a real gneiss. The gabbro has dominant minerals of calcic plagioclase, orthopyroxene, clinopyroxene, and a small amount of biotite. Hamn lies just to the west of the Svanfjellet Shear Zone, which runs WNW-ESE through the map area (http://www.ngu.no/upload/Publikasjoner/Rapporter/2003/2003_011.pdf, http://www.ngu.no/FileArchive/NGUPublikasjoner/Bulletin427_33-36.pdf).

    One of the interesting things about the Hamn mine is that the world's first hydroelectric power plant was built there in 1882, which provided electricity for lights.

  4. And right across the bay is the Skaland graphite mine, which has now hollowed out the first part of the mountain completely. Mining has moved to a smaller deposit further out, which had the side benefit of providing a road to Strandby, a place with two houses and three outbuildings where I was fortunate enough to spend a week some years ago.