Whillans Ice Stream Subglacial Access Research Drilling (WISSARD) and the GeomicroBiology of Antarctic Subglacial Environments (GBASE)

CfG staff: Mitchell, Andrew.

Key collaborators: Dr. John Priscu, Dr Mark Skidmore, Montana State University. Dr. Brent Christner, Louisiana State University. Dr Jill Mikucki, University of Tennessee.

Overview: http://www.wissard.org/

The Whillans Ice Stream Subglacial Access Research Drilling (WISSARD) project is an integrative study of ice sheet stability and subglacial geobiology in West Antarctica, funded in 2009 by the Antarctic Integrated System Science Program of National Science Foundation’s Office of Polar Programs, Antarctic Division.  There are 13 Principal Investigators (PIs) at eight different US Institutions, with International collaborators including the CfG's Andy Mitchell, who is a PI on the GeoMicrobiology of Antarctic Subglacial Environments (GBASE) sub project.

Figure 1‌GBASE is examining distinct, but hydrologically related, subglacial environments using a combination of biogeochemical and genomic measurements to answer key questions directly relevant to metabolic and phylogenetic biodiversity and the biogeochemical transformation of major nutrients beneath the ice sheets and in deep subglacial lakes. The study of life in subglacial ice sheet environments will provide fundamental information on the physiological and molecular properties of the microbiota which exist under dark and cold conditions and will provide a better understanding of biogeochemical processes involved with elemental transformations on our planet.

This research is focusing on the lower portion of the Whillans Ice Stream in West Antarctica where two hydraulically connected subglacial environments are being accessed: (1) Subglacial Lake Whillans, and (2) wet subglacial sediments and the aquatic environment near the grounding zone where the West Antarctic Ice Sheet meets the sea. GBASE has collected microbiological and geochemical samples from the subglacial lake (i.e. bulk water and sediments) during the austral summer of 2012/2013. Here, we successfully drilled an 800m deep, 1 m wide borehole (Figure 1) into subglacial lake Whillans, which represented the first clean access of an Antarctic subglacial lake (Figure 2). We plan to access the grounding zone sites in 2014/2015.  The boreholes were drilled using a hot water drill that utilizes a large volume microfiltration and UV treatment system to continuously "sterilize" the hot water within the borehole to reduce the number of viable microorganisms originating from the melted snow and ice used as the source water for the hot water drill. This approach maintains a pristine subglacial environment and allows us to collect uncontaminated samples (Priscu et al, 2013).

GBASE investigations will provide a better understanding of the biological diversity of the organisms that live in these cold and dark environments, and the biogeochemical processes that occur in and under the ice. As part of the WISSARD program, GBASE is investigating what may be some of the last unexplored aquatic environments on Earth, which represent a potential analogue for extraterrestrial life habitats on Europa and Mars.

Key publications and references:‌‌

Fricker, HA, R. Powell, J. Priscu, S. Tulaczyk, S. Anandakrishnan, B. Christner, D. Holland, H. Horgan, R. Jacobel, J. Mikucki, A. Mitchell, R. Scherer, and J. Severinghaus. Siple Coast Subglacial Aquatic Environments: The Whillans Ice Stream Subglacial Access Research Drilling (WISSARD) project. (2011) M. Siegert and M. Kennicutt (eds), Proceedings of the Chapman Conference on the Exploration and Study of Antarctic Subglacial Aquatic Environments. American Geophysical Union, Washington, D.C. 199-220.

Christner, BC, Priscu, JC, Achberger, A, Mikucki, JA, Michaud, A, Mitchell, AC, Skidmore, ML, Barbante, C, Vick-Majors, T. (in prep) Subglacial Lake Whillians: An ecosystem beneath the Whillans Ice Plain, Antarctica. Nature.

Michaud, Skidmore, ML, Priscu, J, Mitchell, AC (in prep) Biogeochemical weathering in subglacial Antarctic aquatic environments. Geology.

Priscu, JC, Achberger, AM, Cahoon, JE, Christner, BC, Edwards, RL, Jones, WL, Michaud, AB, Siegfried, MR, Skidmore, ML, Spigel, RH, Switzer, GW, Tulaczyk, S and Vick-Majors, TJ (2013). A microbiologically clean strategy for access to the Whillans Ice Stream subglacial environment. Antarctic Science, 25, pp 637-647. doi:10.1017/S0954102013000035.

Mitchell, AC, Lafrenière, MJ, Skidmore, ML, Boyd, ES (2013) Influence of bedrock mineral composition on microbial diversity in a subglacial environment. Geology 10.1130/g34194.1.

National Science Foundation (2009 - 2015) WISSARD/GBASE – (GeoMicrobiology of Antarctic Subglacial Environments). Date Submitted:  June 2008. Co-Principal investigator Proposal No: 0838933.