HR: 1400h
AN: B13B-08    [Abstracts]
TI: Astrobiological and Planetary Exploration Implications of Microbial Ichnofossils in Terrestrial Basaltic Glasses
AU: * Bridge, N J
EM: nbridge@uwo.ca
AF: The University of Western Ontario, Department of Earth Sciences, 1151 Richmond St., London, ON N6A 5B7, Canada
AU: Izawa, M M
EM: matthew.izawa@gmail.com
AF: The University of Western Ontario, Department of Earth Sciences, 1151 Richmond St., London, ON N6A 5B7, Canada
AU: Banerjee, N R
EM: neil.banerjee@uwo.ca
AF: The University of Western Ontario, Department of Earth Sciences, 1151 Richmond St., London, ON N6A 5B7, Canada
AU: Flemming, R L
EM: rflemmin@uwo.ca
AF: The University of Western Ontario, Department of Earth Sciences, 1151 Richmond St., London, ON N6A 5B7, Canada
AU: Schultz, C
EM: cynthiaschultz1@comcast.net
AF: San Jose State University, Department of Geology, San Jose, CA 95192-0102, United States
AB: Over the past decade, studies have demonstrated that terrestrial basaltic glass in pillow rims and hyaloclastites are suitable microbial habitats. Microbes rapidly begin colonizing the glassy surfaces along fractures and cracks that have been exposed to water. Microbial colonization of basaltic glass leads to the alteration and modification of the rocks to produce characteristic granular and/or tubular bioalteration textures. The early precipitation of sub-micron titanite grains within the biologically etched alteration structures serves as an agent for preservation that may persist for geologically extended periods of time in the absence of later penetrative deformation. These microbial alteration structures have been observed in several Archean greenstone belts including the Abitibi greenstone belt (2.7 Ga), Pilbara craton (3.35 Ga), and the Barberton greenstone belt (3.5 Ga). Archean subaqueous volcanic rocks provide an excellent analogue for a potential habitat for possible early Martian life, given that basaltic rocks are a major component of the Martian crust. A wide variety of recent evidence strongly suggests the long-term existence of abundant liquid water on ancient Mars. Recent orbiter, lander, and rover missions have found evidence for the presence of transient liquid water on Mars, perhaps persisting to the present day. Beyond Mars, other solar system bodies, notably Europa, Enceladus, and other icy satellites, may well host subaqueous basaltic glasses. We will explore the implications of the newly discovered geological record of basaltic glass bioalteration and basaltic glass as a microbial habitat for planetary exploration and astrobiology.
DE: 0406 Astrobiology and extraterrestrial materials
DE: 0448 Geomicrobiology
DE: 0702 Permafrost (0475)
DE: 1034 Hydrothermal systems (0450, 3017, 3616, 4832, 8135, 8424)
DE: 5200 PLANETARY SCIENCES: ASTROBIOLOGY
SC: Geological Association of Canada [GA]
MN: 2009 Joint Assembly