Thursday, June 20, 2013

Sunday June 16, 2013

The thermometer shows the temperature is slightly above 0°C but it has been snowing all day; fortunately we do not have field work today so we can enjoy the snow from our rooms while drinking some hot cocoa. It is almost summer but in the Svalbard archipelago it feels like the middle of winter, at least for a Houstonian. I am in Longyearbyen City, located at 78.22°N, 15.65°E in west Spitsbergen, the largest island of Svalbard. The city has a population of a little over 2000 and many tourists this time of the year. I am currently attending a sedimentology field course in the University Centre in Svalbard (UNIS) lead by Maria Jensen, associate professor in sedimentary geology.  Svalbard is located well inside the Arctic Circle, which explains why there is sunlight for 24 continuous hours during the summer and in the winter, the opposite happens, there is no sunlight for 24 continuous hours. This along with the 7-hour time change from Houston made it a little difficult to attain a normal sleeping schedule.

View from the aircraft down to the glaciated mountains in south Spitsbergen, the biggest island in Svalbard on my way to Longyearbyen City.

Longyearbyen City, located on a fjord valley in the Adventfjorden bay, as viewed from Hiorthhamn

I am here as part of the new exchange program between the University of Houston (UH) and University of Stavanger (UiS).  The primary exchange is for students to go between those two schools but also allows for UH students to take specialized classes in Svalbard.

During the first day of the course, all the students were required to attend a safety course. This class is designed to teach students how to work safely in areas where there might be some wild life like polar bears, walruses, artic foxes, and reindeers for example. We also learned how to handle and use rifles and flare guns, which we have to carry every time we go out to the field. Then, we were driven to the harbor where we jumped into the water to test survival suits. These suits are especially designed to float and protect against the cold water and must be worn every time we travel on small boats.

As the name of this class suggests, this is a field course and we will spend most days outside observing and describing outcrops. Usually on Monday mornings we have lectures to introduce us to the subject and in the afternoon we go on a short field excursion. Tuesdays, Wednesdays, and Thursdays are full day excursions and on Fridays we meet in the classroom to present, discuss, and compare our observations with published work on the same or related areas. My classmates come from a wide variety of countries including Iceland, Sweden, The Netherlands, Italy, Switzerland, and Indonesia. 
UNIS student accommodations. These barracks were originally built to house miners and now have been redesigned as dorms for visiting students

The first day of class, Professor Jensen along with an invited lecturer, Dr. Louise Hansen from the Geological Survey of Norway, introduced us to sedimentary processes, valley systems, and gravitational processes. The first field area is just a few meters away from the school, a pebbly river on the Adventdalen area. The river runs from a glacier into the city and out to Adventfjorden, a bay southeast of Isfjorden, the second largest fjord in Svalbard. The water is extremely turbulent and muddy. The clasts are very coarse, angular to sub-rounded, and poorly sorted. Artificial pebbly levees have been built along the river to protect the city but the river preserves mid-channel bars that were probably deposited as bedload sheets, thin deposits of poorly sorted material that move downstream.

The second field area we visited is located on the other side of the bay, around 7 km away from Longyearbyen. To reach our destination, Hiorthhamn, we had to cross Adventfjorden in a zodiac. 
This area used to be a coal mining camp in the early 20th century and today only a few huts remain. The area is also characterized by fan deposits from slush and debris flows. The fans were composed of lobe-like structures, possibly single avalanches that have deposited unsorted material over time (from clay and silt particles to boulders of almost 1 m in diameter). The source area is a rock glacier. Some areas of the fan seem to be inactive since they are vegetated by mosses and even small flourishing plants. 
Students having lunch on fan deposits in Hiorthhamn

In our last excursion day we studied a different fan system in Todalen, north of Longyearbyen. This is a valley with a small river that flows into Adventfjorden. The source area here is siliciclastic outcrops and the grains are much smaller than in Hiorthhamn, still angular and unsorted. The channels and levees formed by the debris and slush flows are as high as 1.5 meters while the fans themselves are around 300 meters wide. Various studies have focused on the distinction between debris and slush deposits since they could be used as paleoclimate indicators because slush flows are directly related to snow.

Students at the beginning of a field day, observing modern fan deposits in Todalen

 I will be applying the lessons of this class to my own research, studying glacial siliciclastic deposits of Antarctica.  I will post again next week with more details about the geology of the region and our next field areas.

Yuribia Muñoz
UH Earth and Atmospheric Sciences PhD Student


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