Friday, August 23, 2013

Kapp Ekholm

Saturday, July 27.  As we packed back onto the Stalbas (I realize that I am spelling it wrong, blogger will not give me the proper a with the circle over it.  I like to call it the angstrom) Friday evening, we headed north.  The intended destination was Poolepynten on Prins Karls Forland.  Poolepynten eluded us on the Sunday prior, by hiding itself with rain.  The weather forecasts were initially good, but as we got closer to PKF, we saw this:

Abandon ship!  Well, perhaps not that dramatic, but needless to say, we did change course.  We headed to Kapp Ekholm, a very familiar site for anyone who has studied Svalbard geology:

Kapp Ekholm is one of the key stratigraphic localities on Svalbard -- four distinct glaciations, dating back to the Late Saalian (~150 ka) have been identified within this site.  Thus, it forms the basis of the glaciation curves proposed for Svalbard.  And here is where we were digging.

Group 2 took KC, Group 3 had KA, and my group had KB.  One thing that might initially strike you about these sections.  They were steep!

But that's cool.  We like danger.

Our group had a dig in the middle part of the section -- essentially, we saw an entire glacial cycle, starting with a diamicton.  We interpreted this diamicton to be a till, based on our discovery of striated clasts within the unit.

Till!  This is a nice picture, because you can see a fairly sharp contact between the lower subglacial till and the upper glaciomarine mud (brown).  This contact shows the transition from a glaciated environment into deglaciation.
And once you deglaciate, you get fauna!  Witness our sand section and all its inhabitants!

Mya truncata and Mytilus edilus used to dominate this place.  The bivalve pictured above is Mya truncata, and he's sort of the definition of ubiquitous.  He lives everywhere, from the tropics to the cold polar regions.  Mytilus edilus (unfortunately, not pictured -- for a closer look, order mussels the next time that you go out for seafood) tells a different story.  He tells us of a warmer climate -- the presence of Mytilus edilus indicates a Holocene climate optimum.  Pretty sweet.  From here on it, it's a straight coarsening upward sequence.

Regression with punctuated debris flow of massive boulders.  

Group 2 had the Holocene glaciation.  Yuribia first explains the diamicton...

And then, she showed us this!

I really like this.  I'm not terribly sure what causes the upward deformation in this imbricated section, but I like it.  It's nice.

By now, we were quite tired from our exertions, and so we had a short respite.

Did I mention the view at Kapp Ekholm?

Across the fjord...

And, perhaps my favorite, evidence of Holocene (like really, really Holocene) kelp-rafted debris!

This is my new favorite dropstone transportation method.

I will end with a small Kapp Ekholm anecdote that may be useful to some who are just beginning their geological career.  Sometimes, you need to crack open a rock.  This may be so that you can identify which rock formation you're in, so you don't screw up your map.  Maybe you've come upon a possible geode, and you want to make sure.  Maybe you are lost in a desolate, formerly shallow sea, and you need to fashion a survival instrument to combat the wild animals lurking amongst the cactus, but limestone is the only material at your disposal (read: Big Bend).  Or maybe you know that a rock is fostering multiple casts and molds, and you really really want to see inside of it.
To accomplish any of these crucial tasks, you need a rock hammer.  And if your rock hammer is stowed in a drawer back on the cruise ship, that task is going to cost you.


Ectoproct (I think from the Fenestrata class) and trace fossils.

This rock cost me a few slices out of my left hand.  Totally worth it.

Take-home point:  Don't forget your hammer.  Ever. 

No comments:

Post a Comment