georefid:2011-097142SEDIS Publication Catalogueana.macario@awi.dehttp://sedis.iodp.org/pub-catalogue/informationpointOfContact2013-07-08T00:00:00Zhttp://sedis.iodp.org/pub-catalogue/index.php?id=10.1130/G32043.1<gco:CharacterString>Episodic seafloor mud brecciation due to great subduction zone earthquakes</gco:CharacterString>2011-01-01publicationgeorefid:2011-097142doi:10.1130/G32043.1Sakaguchi, AritoJAMSTEC (Japan Agency for Marine-Earth Science and Technology), IFREE (Institute for Frontier Research on Earth Evolution), Yokohama, JapanauthorKimura, GakuUniversity of Tokyo, JapanauthorStrasser, MichaelUniversity of Bremen, GermanyauthorScreaton, Elizabeth J.University of Florida, United StatesauthorCurewitz, DanielSyracuse University, United StatesauthorMurayama, MasafumiKochi University, JapanauthorGeological Society of America (GSA), Boulder, CO, United StatespublisherdocumentHardcopyGeology (Boulder)39 (10)919-922The Nankai Trough off southwest Japan has an approximately 1300 yr historical record of great earthquakes, including the most recent, the A.D. 1944 Tonankai (M = 8.2) earthquake. Evaluation of the activity of an individual submarine fault is difficult when only onland observations are available. Submarine core records can pinpoint individual fault activity. Here we present Integrated Ocean Drilling Program (IODP) Nankai Trough Seismogenic Zone Experiment data from the shallow portion. IODP Expedition 316 drilled and cored several holes in the shallow portion of the offshore Tonankai earthquake area, including sites in the hanging wall of a margin-dominating splay fault that has previously been interpreted to have ruptured coseismically during megathrust earthquakes. X-ray computed tomography scanning revealed that the uppermost core at one site contains repeated occurrences of mud breccia. Radioisotope dating of the uppermost mud breccia indicates a deposition time consistent with the 1944 Tonankai earthquake, suggesting that the mud-breccia layers result from episodic brecciation caused by seismic shaking. Mud brecciation provides a potential new tool to reconstruct ancient earthquake history in subduction zones.completedSeismologyAsiabrecciabrecciationclastic sedimentscomputed tomography datacorescoseismic processesdeep-sea environmentearthquakesExpedition 316Far Eastfaultsgreat earthquakesIntegrated Ocean Drilling ProgramJapanmarine environmentmarine sedimentsmudNankai TroughNanTroSEIZENorth PacificNorthwest PacificPacific Oceanpaleoseismicityperiodicityreconstructionsedimentssplay faultssubduction zonesTonankai earthquake 1944troughsWest Pacificurn:org.iodp:exp:316urnlargerWorkCitationcampaignEnglishgeoscientificInformation136.4300136.480033.010033.1400Includes appendix