% IMPORTANT: The following is UTF-8 encoded.  This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.

@INPROCEEDINGS{Stipp:206276,
      author       = {Stipp, Michael and Schumann, Kai and Leiss, Bernd and
                      Ullemeyer, Klaus},
      title        = {{S}ynchrotron texture analysis reveals the cause for
                      mechanical strong behavior of soft {N}ankai accretionary
                      prism sediments from offshore {SW}-{J}apan},
      reportid     = {PUBDB-2015-00781},
      year         = {2014},
      abstract     = {The International Ocean Discovery Program (IODP) is
                      currently exploring subduction and seismogenesis offshore
                      SW-Japan where earthquakes of magnitude 8.0 to 8.5 and
                      related tsunamis recur every 80-100 years. For the
                      tsunamigenic potential of the forearc slope and accreted
                      sediments their mechanical strength, composition and fabric
                      have been investigated. 19 drill core samples were
                      experimentally deformed in a triaxial cell under
                      consolidated and undrained conditions at confining pressures
                      of 400-1000 kPa, room temperature, axial shortening rates of
                      0.01-9.0 mm/min, and up to $64\%$ axial strain. Mechanically
                      weak samples show a deviatoric peak stress after only a few
                      percent strain (< $10\%)$ and a continuous stress decrease
                      after a maximum combined with a continuous increase in pore
                      pressure. Strong samples display a constant residual stress
                      at maximum level or even a continuous stress increase
                      together with a decrease in pore pressure towards high
                      strain. Synchrotron texture and composition analysis of the
                      experimentally deformed and undeformed samples using the
                      Rietveld refinement program MAUD indicates an increasing
                      strength of the illite and kaolinite textures with
                      increasing depth down to 523 m below sea floor.
                      Experimentally deformed samples have generally stronger
                      textures than related undeformed core samples and they show
                      also increasing strength of the illite and kaolinite
                      textures with increasing axial strain. When comparing
                      mechanically weak and strong samples it can be seen that the
                      weak samples have a bulk clay plus calcite content of 31-65
                      $vol.-\%$ and most of their illite, kaolinite, smectite and
                      calcite [001]-pole figures have maxima >1.5 mrd. Strong
                      samples which were deformed to approximately the same amount
                      of strain (up to $∼40\%)$ have no calcite and a bulk clay
                      content of 24-36 $vol.-\%.$ Illite, kaolinite and smectite
                      [001]-pole figure maxima are mostly <1.5 mrd, except for one
                      sample which was deformed to a considerably higher strain
                      $(64\%).$ The higher clay and calcite content and the
                      stronger textures of the mechanically weak samples can be
                      related to a collapsing pore space of the originally
                      flocculated clay aggregates. This process is not effective
                      in the strong samples, but it could be crucial for
                      earthquake rupture, surface breakage and tsunami
                      generation.},
      month         = {Aug},
      date          = {2014-08-14},
      organization  = {17th International Conference on
                       Textures of Materials (ICOTOM-17),
                       Dresden (Germany), 14 Aug 2014 - 29 Aug
                       2014},
      cin          = {DOOR},
      cid          = {I:(DE-H253)HAS-User-20120731},
      pnm          = {DORIS Beamline W2 (POF2-54G13)},
      pid          = {G:(DE-H253)POF2-W2-20130405},
      experiment   = {EXP:(DE-H253)D-W2-20150101},
      typ          = {PUB:(DE-HGF)6},
      url          = {https://bib-pubdb1.desy.de/record/206276},
}