From: Dale Andersen's Astrobiology Field Reports
Posted: Sunday, December 16, 2012
Satellite image showing the location of Lake Untersee and Lake Obersee
9 December 2012
Astrobiologist Dale Anderson and his team visited nearby Lake Obersee today. Lake Untersee is situated at an altitude of 560 meters and more than 100 meters in depth in many places. In contrast, Lake Obersee is located at a higher latitude of 756 meters and is smaller and shallower with a maximum depth of 55 meters.
While at Lake Obersee Dale's team took some water samples. They also dropped a camera into the lake to take an initial look around. Much to Dale's surprise they did not see any of the conical stromatolites that are a prominent feature of Lake Untersee. Either Dale's team did not happen to look at the right spot in Lake Obersee or these conical stromatolites are a feature unique to Lake Untersee. If these conical stromatolites are unique to Lake Untersee, then Dale suspects that there is something special happening in Lake Untersee given that this is the only place on modern day Earth where such features have been observed.
Image: Lake Untersee, Antarctica (-71.348°, 13.448°) Gigapixel Image from the lake: Visit this link to view this immense panorama in all its glory. Credit: Dale T. Andersen
10 December 2012
Dale reports that is was another beautiful day at Lake Untersee. Today the team obtained sediment samples from under the ice at the deep end of Lake Untersee from a depth of approximately 100 meters.
12 December 2012
Dale and his team went back to Lake Obersee to shoot some video and dredge samples from the bottom of the lake. Watching the video shot in Lake Obersee, Dale is convinced that something very special going on in Lake Untersee that is not going on inside nearby Lake Obersee. Lake Untersee is the only place known in modern times where conical stromatolites are being formed. The microbial mats see thus far in Lake Obersee are, in contrast, present as a thin veneer and thread-like in structure. It is important to note that the environmental conditions in and around these Antarctic lakes is very similar to conditions thought to exist on early Mars.
These two lakes are currently not connected in any way but there may have been some interaction in the distant past. Dale's observations in Lake Obersee were made at a depth of 20 meters. Dale thinks that some of the differences in microbial mats and stromatolites may have to do with the underlying rock in the two lakes and how it affects the overlying water composition.
This image of the large conical stromatolites in Lake Untersee was made using a Nikon D3s with a Nikkor 14-24mm lens inside a Subal Housing. Lighting was provided by two Sea & Sea YS-250 Pro strobes in manual mode. Credit: Dale T. Andersen
13 December 2012
Dale made two dives today in Lake Untersee dedicated to vidoegraphy using his Sony EX-1 video camera with him. This was to be followed by another dive focused on still photography of the lake.
The current plan is to depart Lake Untersee between 16 and 17 December. Trucks will come in from Novo station to pack up gear and people and head back. Dale and others will follow on Skidoos and then come back to Lake Untersee to pick up any remaining gear. Weather permitting, they expect to be in Cape Town on the 17 December and on their way home shortly thereafter.
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