HR: 15:25h
AN: T23F-08    [Abstracts]
TI: Microbial Life in Ridge Flank Crustal Fluids at Baby Bare Seamount, Juan de Fuca Ridge
AU: * Huber, J A
EM: jhuber@mbl.edu
AF: Marine Biological Laboratory, Josephine Bay Paul Center, 7 MBL Street, Woods Hole, MA 02543
AU: Johnson, H P
EM: johnson@ocean.washington.edu
AF: University of Washington, School of Oceanography, Box 357940, Seattle, WA 98195
AU: Butterfield, D A
EM: David.A.Butterfield@noaa.gov
AF: University of Washington, Joint Institute for the Study of the Atmosphere and Ocean, NOAA/PMEL, 7600 Sand Point Way NE, Seattle, WA 98115
AU: Baross, J A
EM: jbaross@u.washington.edu
AF: University of Washington, School of Oceanography, Box 357940, Seattle, WA 98195
AB: To determine the microbial community diversity within old oceanic crust, a novel sampling strategy was used to collect crustal fluids at Baby Bare Seamount, a 3.5 Ma old outcrop located in the northeast Pacific Ocean on the eastern flank of the Juan de Fuca Ridge. Stainless steel probes were driven directly into the igneous ocean crust to obtain samples of ridge flank crustal fluids. Genetic signatures and enrichment cultures of microorganisms demonstrate that these crustal fluids host a microbial community composed of species indigenous to the subseafloor, including anaerobic thermophiles, and species from other deep-sea habitats, such as seawater and sediments. Evidence using molecular techniques indicates the presence of a relatively small but active microbial population, dominated by bacteria. The microbial community diversity found in the crustal fluids may indicate habitat variability in old oceanic crust, with inputs of nutrients from seawater, sediment pore-water fluids and possibly hydrothermal sources. This report further supports the presence of an indigenous microbial community in ridge flank crustal fluids and advances our understanding of the potential physiological and phylogenetic diversity of this community.
DE: 0410 Biodiversity
DE: 0448 Geomicrobiology
DE: 0450 Hydrothermal systems (1034, 3017, 3616, 4832, 8135, 8424)
DE: 0456 Life in extreme environments
DE: 0465 Microbiology: ecology, physiology and genomics (4840)
SC: Tectonophysics [T]
MN: Fall Meeting 2005