336
views
0
recommends
+1 Recommend
1 collections
    22
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Expedition 336 summary

      Expedition 336 Scientists

      Proceedings of the IODP

      Integrated Ocean Drilling Program

      Read this article at

      ScienceOpenPublisher
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Integrated Ocean Drilling Program (IODP) Expedition 336 successfully initiated subseafloor observatory science at a young mid-ocean-ridge flank setting. All of the drilled sites are located in the North Pond region of the Atlantic Ocean. This area is known from previous ocean drilling and site survey investigations as a site of particularly vigorous circulation of seawater in permeable 8 Ma basaltic basement underlying a <300 m thick sedimentary pile. Understanding how this seawater circulation affects microbial and geochemical processes in the uppermost basement was the primary science objective of Expedition 336. Major strides in ridge-flank studies have been made with subseafloor borehole observatories (CORKs) because they facilitate combined hydrological, geochemical, and microbiological studies and controlled experimentation in the subseafloor. During Expedition 336, two fully functional observatories were installed in two newly drilled holes and an instrument and sampling string were placed in an existing hole.

          Related collections

          Most cited references 33

          • Record: found
          • Abstract: not found
          • Article: not found

          Iron and sulfide oxidation within the basaltic ocean crust: implications for chemolithoautotrophic microbial biomass production

            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Channelized fluid flow in oceanic crust reconciles heat-flow and permeability data

             A Fisher,  K. Becker (2000)
            Hydrothermal fluid circulation within the sea floor profoundly influences the physical, chemical and biological state of the crust and the oceans. Circulation within ridge flanks (in crust more than 1 Myr old) results in greater heat loss and fluid flux than that at ridge crests and persists for millions of years, thereby altering the composition of the crust and overlying ocean. Fluid flow in oceanic crust is, however, limited by the extent and nature of the rock's permeability. Here we demonstrate that the global data set of borehole permeability measurements in uppermost oceanic crust defines a trend with age that is consistent with changes in seismic velocity. This trend-which indicates that fluid flow should be greatly reduced in crust older than a few million years-would appear to be inconsistent with heat-flow observations, which on average indicate significant advective heat loss in crust up to 65 Myr old. But our calculations, based on a lateral flow model, suggest that regional-scale permeabilities are much higher than have been measured in boreholes. These results can be reconciled if most of the fluid flow in the upper crust is channelized through a small volume of rock, influencing the geometry of convection and the nature of fluid-rock interaction.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Alteration of oceanic volcanic glass: textural evidence of microbial activity

              The subsurface biosphere may constitute as much as 50 percent of Earth's biomass. Direct and indirect evidence suggests that an extensive biosphere exists in the rocks below the sea floor. This survey of basalts of the Atlantic, Pacific, and Indian Oceans supports the hypothesis that bacteria have colonized much of the upper oceanic crust, which has a volume estimated at 10(18) cubic meters. Although this is the largest habitat on Earth, its low abundance of bacteria constitutes much less than 1 percent of Earth's biomass.
                Bookmark

                Author and article information

                Journal
                10.2204/iodp.proc.336.2012
                Proceedings of the IODP
                Integrated Ocean Drilling Program
                1930-1014
                16 November 2012
                Article
                10.2204/iodp.proc.336.101.2012

                This work is licensed under a Creative Commons Attribution 4.0 Unported License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/

                Product
                Self URI (journal page): http://publications.iodp.org/

                Comments

                Comment on this article