Geology... Glaciology... and Avalanches... Oh My!! (June 17)

Wednesday, June 17, 2009

Today's theme was Geology and Glaciology. Today we were greeted with beautiful sunny day... the winds calmed down after our adventurous night with the barracks shaking in the wind... haha. Our day at UNIS started out with an introduction to geology - specifically the unique geology of Svalbard. The lecture was given by Dr. Hanne Christiansen. We learned that the oldest rocks on Svalbard have been dated to be from 1.27 Billion to 410 million years ago... that's just insane! We also were made aware that the island of Svalbard has traveled quite a lot around the globe during the rearrangements of the earth's plates through the past billion years. 450 million years ago Svalbard was located near teh equator (Alaska too)... the mountains here were formed when the coast collided with Greenland. During the "Age of the Dinosaurs" Svalbard moved from 45 degrees N latitude to 60 degrees N latitude... as a matter of fact there are many many fossils of plant life here in the arctic confirming it used to be in a much more tropical environment. Dinosaur fossils have been found here as well in the past few decades, and the coal that is now mined here was the result of the compression of vegitation and plant life during the Jurassic Period... How Cool is that?! During the past 2-3 million years Svalbard has moved to it's current location and been through ab out 30-50 major glaciations. Now Svalbard is 60% covered by glaciers.

The second set of lectures during the day covered Glaciology and they were presented by Monica Sund. I learned So much about glaciers... SOOOoooo interesting! WE covered the parts of glaciers and how they move and act... On Svalbard the fastest moving glacier is Kronebreen (moving approximately 600 meters a year... that's almost 2 meters a day!), and the slowest which is more typical (4 meters per year). Another really interesting topic we covered was glacial surges... I had no clue what these were previous to today! [Taken as a quote from Dr. Sund's webpage here is a definition of a glacial surge]
"Glacier surges are characterized by cyclical advances related to internal changes in the glacier system, and occur in both terrestrial and tide-water glaciers. The surges are short-lived periods of rapid movement and usually advancing terminus, usually lasting 2 - 10 years." Basically a glacial surge involves a large mass from the glacial moving down to a lower part of the glaciar suddenly (well relatively suddenly...we're talking over the course of a couple years) in which case the glacier may calve if on a body of water or advance...

Check out Dr. Monica Sund's website to see time-lapse video of glaciers actually moving over the course of a year! It's amazing!
http://www.unis.no/35_STAFF/staff_webpages/geology/monica_sund/web/New/monica_sund_homepage.htm

Now it's also important to note that all those images you see on tv of glaciers calving (when huge pieces fall into the ocean) aren't necessarily images of the so called "global warming". It is clear that throughout the past decades glaciers constantly advance and retreat... it's just a process. In many cases calving will occur simply because the shelf is unstable. There is still a lot to be researched on this topic to see how future changes in climate patterns may effect glaciers... it's all a very complicated scientific puzzle that is very difficult to solve.

After lecture we hiked back up to Nybyen and had a short talk about the Longyearbyen glacier right behind our baracks. The original plan was to hike up to it, but as we had just received snowfall the day before we decided against it and had a new field activity helping with an avalanche study.

We learned about the different avalanches they get here in Svalbard and saw examples of the snow cornices on the mountains right beside our baracks in the valley... then we learned about the plan for the day. We split into two groups... for this project we were to measure out a 4x4 area on top of the snow surface where an avalanche had fallen earlier in the season... depositing snow and rocks from the mountain. The goal was to then gather all of the rocks in this area, weigh them, and record the location and angle of the study region. The data we collected was going to be used in a research project to prove that these avalanches really do move a lot of rock down the mountainside. I headed up in the first group... quite the vertical hike up the side of the mountain as you can see here. We started working and after finishing up our first "square" we heard this crack sound and rumbling.. hard to describe... then we looked up and saw some snow falling and a few rocks... we looked over to the project instructor and he was like "Move Move!!" haha... we were so intrigued by what was going on none of us had decided to shift over out of the way of the tumbling debris! haha... Anyways after that we decided it would be wiser to work on the lower portion of the mountain... so after a few photos at the top we hiked carefully back down and helped the group at the bottom. It was a pretty fun afternoon on the mountainside!