Van Keulenhamna

Friday, July 26  -- Van Keulenhamna.  We literally took a westerly skip over the fjord to get to this place.

Today, Svalbard graced us with one of her gorgeous sunny ... well, it's always day.  I will go with sunny 12 hour window.

So.  Van Keulenhamna.  Here's a view looking back at the Stalbas:

First thing to notice (I will get to the awesome fold tucked away in the mountains later...).  The beach is mainly gravel, and this is clearly visible.  The beach is also not flat -- there are many little (seriously little) ridges and valleys cutting across it.  And this raised beach goes on for quite a ways...

(Person for scale, above)

We're in marine terrace territory now.  No sections today.  Today, we level the raised beaches, and we use a theodolite to do it.

This surveying technique creates a very precise vertical profile across the entire terrace.  We began the survey at the high tide mark -- an easily recognizable starting point.  The person peering through the theodolite (in this case, Krzysztof) sights the several meter high stick through the lens.  The height is recorded, in some cases to the centimeter, and the surveying continues until the sighter can no longer see the stick.  This is an image of the front-sighting technique.  It's nice and literal -- backsighting occurs when the theodolite is ahead of the stick, and turns around to face it.  Here is what you see:

We operated the theodolite in shifts -- first Group 3, then Group 1, and Group 2 took the last profiles.  I was super jealous of them, because they went all the way to the marine limit.  And then they got this amazing picture:

They're really high up.  The only rocks I climbed today weren't strictly speaking within my working duties.  But rocks sometimes call to be climbed upon, because you can see great things like this!

 

Now you can play your own game of Spot the Ectoproct, Coral, and Brachiopod fragment.

The theodolite was not the only goal of today's field work, however.  We also got to play detective!

Here we employ our finest CSI techniques as we search for pumice.  Happily, pumice is a very distinctive volcanic rock.  It's texture is highly vesicular, it's density much lower than the gravel on the beach, and we were looking for pumice in a pitch black shade.

Iceland pumice.  We expect that this pumice was transported via ocean to Svalbard.  There are volcanoes on Svalbard, and some of them active as recent as the Quaternary, but these are primarily in northwestern Spitsbergen (Sverrefjellet is a good example).  Not exactly close enough to spit pyroclastic material directly onto this beach, but you never know.  To ensure that this pumice is related to Icelandic eruptions, the petrology of each sample will need to be examined and compared to samples recovered in Iceland.


We also looked for intact shells in proximity to the pumice.  This was a largely unsuccessful venture, but it did afford us many opportunities to use random objects as digging tools, locate cool looking rocks, and take the occasional cowboy nap.

The view was truly spectacular.

This nearly vertical strata houses a rock glacier in the center.

 This is just awesome.

And one jump shot of me and Ingunn to end the day.

Skilvika

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:

Leinstranda

Wednesday, July 23rd.  Today, we sailed to Leinstranda.  My group is the reporting group for today.

Leinstranda is tucked away behind the northern tip of Prins Karls Forlund.  This locality keeps it in a inter-fjord area, meaning that Leinstranda did not directly interact with any major ice streams, which Kongsfjordhallet and St. Jonsfjorden certainly did.  Leinstranda was our first "protected" area.  

If you've had sedimentology, or even just physical, you know that geologists have many different descriptors for lithologic units.  Diamicton is one of those terms, and it includes all manner of unsorted, different sized, varying lithology sediment within a mud or otherwise fine grained matrix.

So.  Glacial fun fact.  When a glacier grounds into the sea floor, we can directly evidence its grounding position by locating a till.  Till is diamicton that is deposited directly by glacial activity.  That is what separates it from diamicton.  

Witness my first ever till!

Here, Kaleb explains what group 2 noticed in their findings.  Boulder sized particles, red till.  We generally differentiate till from diamicton by the presence of striated clasts.  Striations typically form as a direct result of a big, weighty glacier sitting on top of a rock, scratching the crap out of it.  Here's a better look at the till (Unit 2b), underlain by a diamicton (Unit 2a), and overlain by glaciomarine mud (dark brown, unlabeled).  Unit 1 is the continuation of a sandy unit that group 3 discovered.

Much thanks to Kaleb for annotating this image!

Anyways, TILL!  I've read about them many times, but this was my first up close encounter.

More things besides till happened -- here's a quick overshot of where we were sectioning:

 

 

 We go pretty much in a diagonal -- group 1 at the top NW, then group 2 in the center, group 3 more easterly (I demand that this is a word!), easily identified by Liz's green jacket. 

My group was in charge of sectioning the sand deposits.

  

Jon is cleaning the "party" layer.  Here's an up close shot:

 

We think this bedding looks heterolithic -- wavy, to be specific.  Wavy bedding consists of alternating sand and mud (or clay) layers, and generally occurs in tidally influenced areas.  After this layer, we had the "business" layer, so called because it had less cool structures.

Cool structures like this sediment deformation!

 

Very cool stuff -- we're looking at the continued retreat of one of the glaciers -- there were at least three acting on the area during the pullback.  Just one remains visible now:

 

We ended the day with jumping shots, which I forgot to be in because I was busy taking them.

Group 1!  Iceland, Denmark, Norway, and the American behind the camera.

Ny-Ålesund

Tuesday evening, July 22^nd.  After our field day in Kongsfjordhallet and hike to Bromsterhamna, we sailed to Ny-Ålesund.

Twenty six people live in this town.  It's one of four permanent living settlements in Svalbard.  It The permanent population is entirely research scientists, with visiting students and other transient scientists year-round.  Tourists are allowed, but you're not permitted to stray from the beaten path.  Seriously, there are ropes that keep you in.  I might've slightly snuck off the path to visit a greenhouse, and I was immediately divebombed by an Arctic tern.  They are vicious, loud, and, I suspect, trained.  Ny-Ålesund is essentially a town of pure science. See the satellite dish?  It’s a nice scale for the faulting.

Plus one bar,

 a mining museum,

and a sled dog kennel.

Sadly, I was not allowed into the dog kennel.  I might note that I took all of those pictures at around 9-930 in the evening.  It was a really beautiful night.  Many of us took the opportunity to shop the Ny-Ålesund  buttiken and send postcards to our families from the most northern post office in the world.

On our way back to the ship, we noticed this:

For scale, here is a shot of Yuribia, Kaleb, me, and the dirty, stratified iceberg floating in the harbor.

We are actually facing the source that calved this berg.  He came from either Conwaybreen (right) or Kronebreen (left):

Pretty amazing.  We got about 400 meters from the calving face of Kronebreen.  A seal swam along with us for a short time, but I couldn’t manage to get a great picture of him.  I settled for one of us instead:

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.