Thursday, August 1, 2013

Kongsfjordhallet


            Today, we ventured to Kongsfjordhallet.   

Mercifully, it rained for only minutes.  The clouds lifted, and we had a view across the fjord:


            I was already familiar with Kongsfjorden, having covered it in my presentation given during our short week of seminars.  My topic was “Seafloor fingerprints of the Svalbard-Barents Sea Ice Sheet deglaciation”.  This topic was pretty perfect for me, since my masters thesis deals primarily with bathymetry and shallow seismic.  These techniques, when backed up with the acquisition of marine sediment cores, are how scientists construct continuous marine records of glaciation/deglaciation events.  So I’ve seen the seafloor of Kongsfjorden.  But that’s not really what we were doing today.  But just for fun, here’s a picture of the surface of Kongsfjorden.



Today, I had my first experience with section descriptions.  Here she is.



Look upon our glorious section of glaciofluvial deposits overlain by a solifluction lobe!  Prior to this course, I had not heard of solifluction lobes.  They are quite common in permafrost environments.  The saturation of water in the ground causes creep, or slow movement, of the moraine material.  You can be relatively sure of this process because you will see increased vegetation within the lobe, and boulders and cobbles will be pushed outward in a curvilinear pattern on the ground surface (so you have that nice “lobe” shape).  Basically, the ground is flowing.  We dug into the top of the observable surface solifluction lobe to make sure that it correlated with the top of our section.


It matched.  Top of section solved.  We interpreted the rest of our section to be primarily glaciofluvial deposits, as these often form near meltwater channels (very close to the eastern part of our section.  Braided river systems are very common near and within glacial drainage areas.

The solifluction lobe was not the only evidence of permafrost in the area!  Look at these!


Frost circles!


More frost circles (Jón for scale)!



Yeah, these are just really really cool.  No one is completely sure exactly how they form – it is known that permafrost processes can cause sorting – generally the older material is in the center of the frost circle, hence the color change. 

They also come in zebra stripes (Andrea for scale)…


            We spent the morning and afternoon in the sections.  At the end of the afternoon, each group describes and explains their section.  It helps to put the depositional history of the sections in perspective, which lays the foundation for reconstructing glacial events.  After the section discussions, we had a nice hike to Blomsterhamna.  We passed several really amazing things.  Like this massive whale skull (whalebone is pretty significant in dating these areas):



And this beautiful marble formation (we have metamorphism!):


And natural iceberg artwork:


And this:


It’s the Kodak moments in front of a glacier front that count.

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