{"id":252,"date":"2012-10-08T03:41:02","date_gmt":"2012-10-07T18:41:02","guid":{"rendered":"http:\/\/www.eri.u-tokyo.ac.jp\/_html\/en\/?p=252"},"modified":"2016-04-14T17:02:28","modified_gmt":"2016-04-14T08:02:28","slug":"depth-dependent-mode-of-tremor-migration-beneath-kii-peninsula-nankai-subduction-zone","status":"publish","type":"post","link":"https:\/\/www.eri.u-tokyo.ac.jp\/en\/research\/252\/","title":{"rendered":"Depth-dependent mode of tremor migration beneath Kii Peninsula, Nankai subduction zone"},"content":{"rendered":"<p style=\"text-align: center\"><strong>Depth-dependent mode of tremor migration beneath Kii Peninsula, Nankai subduction zone<\/strong><\/p>\n<p style=\"text-align: center\">Kazushige Obara<span style=\"font-size: 11px\">,\u00a0<\/span>Takanori Matsuzawa<span style=\"font-size: 11px\">,\u00a0<\/span>Sachiko Tanaka\u00a0and Takuto Maeda<\/p>\n<p style=\"text-align: center\"><a href=\"http:\/\/www.agu.org\/pubs\/crossref\/2012\/2012GL051420.shtml%20\" target=\"_blank\">GEOPHYSICAL RESEARCH LETTERS, VOL. 39, L10308, doi:10.1029\/2012GL051420, 2012<\/a><\/p>\n<p>&nbsp;<\/p>\n<p><strong>Abstarct<\/strong><\/p>\n<p>We investigated the migration mode of deep non-volcanic tremor activity beneath Kii Peninsula, southwest Japan. Major tremor episodes are characterized by long-term migration with a velocity of about 10 km\/day, propagating along the strike of the subducting plate. Similar tremor migration in Cascadia is accompanied by reverse propagation at speeds on the order of 100 km\/day and much faster slip-parallel migration at speeds on the order of 1000 km\/day. We systematically searched for migrating tremor with clear linearity in space and time. As a result, we found tremor migrations at speeds ranging from 1 to 60 km\/hr depending on the along-dip position in the tremor zone. The observed decrease in migration speed with increasing measurement time scale suggests that migration is controlled by a diffusion process. The along-strike migration at lower speeds, including both forward and backward directions relative to the long-term migration episode, is concentrated at the updip side of the tremor zone, whereas the faster slip-parallel migration is distributed over the entire zone. The long-term migration seems to consist of and be excited by the propagation of along-strike creep at the updip part. The concentration of along-strike migrating tremor sequences at the updip side may reflect the existence of abundant fluid that accumulates at the corner of the mantle wedge. The faster slip-parallel migrations represent projections of along-strike fluctuations in slip pulse propagation controlled by striations along the plate interface.<\/p>\n<p style=\"text-align: center\"><a href=\"http:\/\/www.eri.u-tokyo.ac.jp\/old\/wp-content\/outreach-old\/uploads\/2012\/10\/obara8_1.gif\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone\" title=\"obara8_1\" src=\"http:\/\/www.eri.u-tokyo.ac.jp\/old\/wp-content\/outreach-old\/uploads\/2012\/10\/obara8_1.gif\" alt=\"\" width=\"454\" height=\"226\" \/><\/a><\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Depth-dependent mode of tremor migration beneath Kii Peninsula, Nankai subduction zone Kazushige Obara,\u00a0Takano &hellip; <a href=\"https:\/\/www.eri.u-tokyo.ac.jp\/en\/research\/252\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Depth-dependent mode of tremor migration beneath Kii Peninsula, Nankai subduction zone&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11],"tags":[],"class_list":["post-252","post","type-post","status-publish","format-standard","hentry","category-research"],"_links":{"self":[{"href":"https:\/\/www.eri.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/posts\/252"}],"collection":[{"href":"https:\/\/www.eri.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.eri.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.eri.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.eri.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/comments?post=252"}],"version-history":[{"count":1,"href":"https:\/\/www.eri.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/posts\/252\/revisions"}],"predecessor-version":[{"id":253,"href":"https:\/\/www.eri.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/posts\/252\/revisions\/253"}],"wp:attachment":[{"href":"https:\/\/www.eri.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/media?parent=252"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.eri.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/categories?post=252"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.eri.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/tags?post=252"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}