Astrobiologists Discover Strange Benthic Microbial Mats in Antarctica
Benthic microbial mats in Lake Untersee. Photo copyright: Dale T. Andersen 2011.
Photosynthetic microbial mats forming large conical structures up to half a meter tall have been discovered by astrobiologists in Lake Untersee, Antarctica. This research is described in an article in the May 2011 issue of the journal Geobiology.
Lake Untersee is located at 71°20'S, 13°45'E in the Otto-von-Gruber-Gebirge (Gruber Mountains) of central Dronning Maud Land. [Download Google Earth .kmz file of Lake Untersee]. The lake is 563 meters above sea level, with an area of 11.4 square kilometers and is the largest surface lake in East Antarctica.
During the expedition, three members of the field team, Dale Andersen (SETI Institute), Ian Hawes (University of Canterbury), and Chris McKay (NASA ARC) explored the lake beneath its 3 meter thick ice-cover and discovered the large conical structures that dominate the under-ice landscape.
To date, there have been no other reports of modern microbial mats forming such structures, which resemble a class of stromatolites termed large complex cones that were present on Earth approximately 3.4 billion years ago in the Pilbara (see Allwood et al. Nature, Vol 44, 2006).
Studies of these structures will help scientists interpret the record of life preserved in rocks and will hopefully provide new insights about the communities of microorganisms of Earth's earliest biosphere.
Support for the multinational project was a mix of private and govt funds via the Tawani Foundation, NASA's Astrobiology program, and Russia's Arctic and Antarctic Research Institute (AARI).
Discovery of large conical stromatolites in Lake Untersee, Antarctica, Geobiology
Volume 9, Issue 3, pages 280-293, May 2011, Andersen, D. T., Sumner, D. Y., Hawes, I., Webster-Brown, J. and McKay, C. P. (2011), Discovery of large conical stromatolites in Lake Untersee, Antarctica. Geobiology, 9: 280-293. doi: 10.1111/j.1472-4669.2011.00279.x
Ian Hawes collecting samples of the benthic microbial mats in Lake Untersee. Photo copyright: Dale T. Andersen 2011.
Dale Andersen begins a dive under the ice. He is about to be handed a Sony Ex1 video camera. Photo copyright: Dale T. Andersen 2011.
Dale Andersen using a portable compressor to charge diving gear. Photo copyright: Dale T. Andersen 2011.
Lake Untersee Base Camp as seen from a nearby hill. Photo copyright: Dale T. Andersen 2011.