HR: 1340h
AN: T33A-0524    [Abstracts]
TI: Improved Access To Aging Ocean Basement Biosphere For Microbial Geochemical Studies
AU: * Cowen, J P
EM: jcowen@soest.hawaii.edu
AF: School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu, HI 96822 United States
AU: Glazer, B
EM: glazer@hawaii.edu
AF: Institute of Astronomy, UH-NAI, University of Hawaii at Manoa, Honolulu, HI 96822 United States
AU: Rappe, M
EM: rappe@hawaii.edu
AF: School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu, HI 96822 United States
AU: Kenig, F
EM: fkenig@tigger.cc.uic.edu
AF: Earth and Environmental Sciences, University of Illinois, Chicago, IL 60607 United States
AU: Fisher, A
EM: afisher@ucsc.edu
AF: Earth Sciences Department, University of California, Santa Cruz, CA 95064 United States
AU: Copson, D
EM: copson@hawaii.edu
AF: School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu, HI 96822 United States
AU: Harris, D
EM: harris@hawaii.edu
AF: School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu, HI 96822 United States
AU: Jolly, J
EM: jjolly@hawaii.edu
AF: School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu, HI 96822 United States
AU: Nuzzio, D
EM: ais@aishome.com
AF: Analytical Instruments Systems, P.O. Box 458, Flemington, NJ 08822 United States
AB: CORK observatories affixed to Integrated Ocean Drilling Program (IODP) boreholes offer an unprecedented opportunity to study biogeochemical properties and microbial diversity in circulating fluids from sediment-buried ocean basement. Preliminary 16S rRNA gene sequence data from 65 degrees C fluids escaping from the top of the over-pressured ODP borehole 1026B, on the flanks of the Juan de Fuca Ridge indicated the presence of diverse Bacteria and Archaea, including gene clones with varying degrees of relatedness to known dissimilatory nitrate reducers (with ammonia production), thermophilic sulfate reducers, and thermophilic fermentative heterotrophs, consistent with fluid chemistry measurements. However, questions remain regarding microbial community structure, key metabolic pathways and rates, and redox chemistry of the basement fluids, along with concerns for contamination issues. We describe ongoing developments intended to address key in situ analytical and sampling challenges including: 1) The new generation CORKs' dedicated microbiological/geochemical fluid delivery system specifically designed to minimize chemical contamination and surface biofouling; and 2) Development of a seafloor instrument sled for coupling to the CORK's bio-fluid delivery system for acquisition of real-time, in situ electrochemical (voltammetry) redox chemistry data on basement fluids, in addition to in situ particle filtration of basement fluids for molecular genetics, culturing and biogeochemical studies. Results of the first deployment of this instrument sled to new CORK observatory 1301A in Cascadia Basin, on the flanks of the Juan de Fuca Ridge, will be described.
DE: 0406 Astrobiology and extraterrestrial materials
DE: 0420 Biomolecular and chemical tracers
DE: 0424 Biosignatures and proxies
DE: 1037 Magma genesis and partial melting (3619)
DE: 3021 Marine hydrogeology
SC: Tectonophysics [T]
MN: Fall Meeting 2005