caa a22 4500 463216261 CHVBK 20180405153157.0 cr unu---uuuuu 170326e20070601xx s 000 0 eng 10.1007/s00367-007-0080-4 doi (NATIONALLICENCE)springer-10.1007/s00367-007-0080-4 Fabric of gas hydrate in sediments from Hydrate Ridge—results from ODP Leg 204 samples [Elektronische Daten] [F. Abegg, G. Bohrmann, J. Freitag, W. Kuhs] Drilling on Hydrate Ridge, offshore Oregon, during ODP Leg 204 enabled us to investigate fabrics of gas hydrate samples in a wide depth range of the gas hydrate stability zone (GHSZ). X-ray computerized tomographic imaging on whole-round samples, frozen in liquid nitrogen, revealed that layered gas hydrate structures are related to variable processes occurring at different sediment depths. Shallow gas hydrates often form layers parallel or sub-parallel to bedding and also crosscut sedimentary strata and other gas hydrate layers, destroying the original depositional fabric. The dynamic processes interacting with this complicated plumbing system in this shallow environment are responsible for such highly variable gas hydrate fabrics. Gas hydrate layers deeper in the sediments are most often dipping with various angles, and are interpreted as gas hydrate precipitates filling tectonic fractures. These originally open fractures are potential candidates for free gas transportation, and might explain why free gas can rapidly emanate from below the bottom-simulating reflector through the GHSZ to the seafloor. Springer-Verlag, 2007 Abegg F. Research Center Ocean Margins, University of Bremen, 28334, Bremen, Germany aut Bohrmann G. Research Center Ocean Margins, University of Bremen, 28334, Bremen, Germany aut Freitag J. Alfred-Wegener-Institut für Polar- und Meeresforschung, 27568, Bremerhaven, Germany aut Kuhs W. GeoZentrum Göttingen, Abt. Kristallographie, University Göttingen, 37077, Göttingen, Germany aut Geo-Marine Letters Springer-Verlag 27/2-4(2007-06-01), 269-277 0276-0460 27:2-4<269 2007 27 367 https://doi.org/10.1007/s00367-007-0080-4 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00367-007-0080-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Abegg F. Research Center Ocean Margins, University of Bremen, 28334, Bremen, Germany aut NATIONALLICENCE 700 1- Bohrmann G. Research Center Ocean Margins, University of Bremen, 28334, Bremen, Germany aut NATIONALLICENCE 700 1- Freitag J. Alfred-Wegener-Institut für Polar- und Meeresforschung, 27568, Bremerhaven, Germany aut NATIONALLICENCE 700 1- Kuhs W. GeoZentrum Göttingen, Abt. Kristallographie, University Göttingen, 37077, Göttingen, Germany aut NATIONALLICENCE 773 0- Geo-Marine Letters Springer-Verlag 27/2-4(2007-06-01), 269-277 0276-0460 27:2-4<269 2007 27 367 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer