Friday, August 9, 2013


Thursday, July 24th.  During the night, we headed south for Skilvika.  It was ... rough seas.

When I was aboard the R/V Araon, a ship upon which I stayed for 33 days in and en route to and from Antarctica, I got seasick only once.  And I might mention that the "once" in Antarctica was in the Bransfield Strait, during a pretty serious storm.  I still managed to log something like ten hours in multibeam data before I had to leave and hide in my bunk.  I survived the Drake Passage both ways (though we definitely had a Drake Lake on the way in). 

My sea-legs are apparently fake.  I, along with several of my classmates, was bed-bound during a significant part of this cruise.  The trek to Skilvika might have been the worst. 

In any case, we did arrive to blue (sort of) skies.

You can really see the raised beaches in this last photo.  Raised beaches are a signature of glacio-isostatic rebound.  When an ice sheet builds up, the heavy weight of it causes an isostatic depression on the crust beneath the sheet.  The bigger the sheet, the deeper the depression.  When the ice sheet retreats, the crust will begin to rebound, but not before multiple sedimentary deposits have been made.  Usually, this goes in the cycle, from bottom-up, of a till (the glacial extent), glaciomarine mud (the initial pullback), and then the depositional environment can really begin to vary.  You might get sand or gravel deposits (this is the general case that I have seen in our travels)...or you might get something else!  These are the detective clues in putting the ice sheet back together.

Group 1 got the Skilvika till.  Here we are, overlaying the bedrock.

We had to dig out a lot of mud to reach the till.  Jon really enjoyed the mud, and the picture taking that went with it.

I call this the Magpie picture.  No one has to worry about running out of scale objects in this section!  You're welcome, reporting group 2.

We did eventually find the till.

The field notebook marks the transition between glaciomarine mud and till.  You can see a change in texture and color.  At the very bottom of the picture, if you squint, you can make out a bit of oxidation.  We suspect those are weathered dropstones.  Over time, they have "grown" little oxidation halos. 

We also found this nearby:

 This is a polar bear track, and, unfortunately, is the closest that we got to actually witnessing a polar bear, because the stuffed one that they roll out for the tourists in Longyearbyen doesn't count!  Good thing we travel prepared in Svalbard!

Yuribia and group 2 got the steeply dipping gravel foresets.  Seriously steep.

Yikes to the foresets.  Other cool things about today:

Hiking to Scottbreen.  Here's what he looked like from far away...

We crossed a few baby moraines and ravines.  It began to rain.  And here's Scottbreen up close:

This glacier is obviously in retreat.  First clue: there is no calving front.  The glacier is no longer terminating in the sea, and it's got a giant puddle of meltwater in front of it.  That meltwater channel forms a nice braided river system that we later had to cross.

Scottbreen has retreated a full 2.3 km from the shoreline.  We followed his little river system all the way to the beach, where we stopped for a bit of tea at a Polish workstation (where they are working on glaciology, I believe).

And then, tillite!

This is what happens when a till gets buried and lithified.  

And this is what happens when you have a hot tub on board a cruise ship, and the students have had a successful day:

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