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Friday, 6 January 2017

Gallery -- Putorana and Vestfirdir

There are remarkable similarities between the "glaciated trap landscapes" of Putorana in Siberia and Vestfirdir in Iceland.  Flat-bedded basalt layers, flattish plateau surfaces, and deeply incised troughs cut by powerful ice streams.  The main difference is that Vestfirdir is at the coast, with many of the deepest troughs now containing fjords or arms of the sea.  Putorana is far inland, and the troughs are still dry, apart from a few which contain long finger lakes.

Five from Vestfirdir (thanks to Mats Wibe Lund and Murray Foote):


And four from Putorana:


1 comment:

  1. An interesting tranche of glacial information. I was particularly interested by the illustration of the Russian view of the extent of the ice sheets. The southern margins were much further north than I would have expected. I guess it is to do with lack of humidity to feed the ice.

    In my work in Azerbaijan, I've always had glaciation at the back of my mind. Certainly the two Caucasus ranges are tall enough to have snow in sheltered areas for a lot of the year today, but to what extent were peri-glacial features to be found in the foothills and plains below the mountain ranges?

    The illustration also shows the extent of the inundation of the Kura valley from high level stands of the Caspian Sea. I've worked on plenty of evidence of that, the other issue is low water levels probably caused by the flow of water into the Caspian from one of the main sources, the Ural river, being locked up in the northern ice sheets.

    Many of the rivers feeding the Kura have terraces formed as a result of the Kura being blocked by high levels of the Caspian and later rejuvenation due to Caspian low levels. working out what is what is the hard part.

    Dave

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