{"id":2910,"date":"2020-07-10T09:08:12","date_gmt":"2020-07-10T00:08:12","guid":{"rendered":"http:\/\/www.eri.u-tokyo.ac.jp\/en\/?p=2910"},"modified":"2020-07-10T09:09:24","modified_gmt":"2020-07-10T00:09:24","slug":"%e3%80%90qe%e3%80%91seismic-and-infrasound-observation-in-nishinoshima-island","status":"publish","type":"post","link":"https:\/\/www.eri.u-tokyo.ac.jp\/en\/news\/2910\/","title":{"rendered":"\u3010QE\u3011Seismic and infrasound observation in Nishinoshima island"},"content":{"rendered":"\n

Volcanic activity\nof Nishinoshima island amongst Bonin Islands, has been continuing since 2013\nand the island is rapidly expanding due to its repeated lava outflows.<\/p>\n\n\n\n

In October 2016\nand September 2019, our team landed on the previously formed part of the island,\nand installed seismometers and infrasound sensors in between the volcanic activities.\nThe observation instruments installed in October 2016 was lost due to eruptions\nin April 2017, but fortunately, seismic and infrasound signals just before and after\nthe beginning of the eruption was recorded. In September 2019, our team landed\nagain on the previously formed land that was not covered by lava flows, and re-installed\nthe instrument consisting of 3-component broadband seismograph and infrasound\nsensor. This report introduces the observation that began in September 2019.<\/p>\n\n\n\n

Most of the older\npart of the island was covered by repeated lava outflow, but as of September\n2019, soil surface was slightly left and many sea birds inhabited (fig.1). We\nburied the seismometer, digging a hole of 30cm deep hole on a tiny piece of the\nsoil covered land that was not covered by lava flows (fig.2).<\/p>\n\n\n\n

The electric power for observation instruments\nare supplied by solar panels, and the data are sent to ERI via satellite link. <\/p>\n\n\n\n

Due to the limitation\nin satellite communication capacity and cost, it is not possible to transmit all\nthe recorded data, so the data were collected by the following procedure:<\/p>\n\n\n\n

  1. After\none day of observation, the local logger creates and compresses the running\nspectrum for the previous day, and send it to ERI.<\/li>
  2. Check\nthe running spectrum manually and if an earthquake or any other events occur,\nwe manually cut out the data at the relevant time and collect them later.<\/li>
  3. This\nprocedure made it possible to grasp the overview of the volcanic activity under\nlimited communication conditions.<\/li><\/ol>\n\n\n\n
    \"\"
    Fig.2 This is how the seismometer was installed. <\/figcaption><\/figure><\/div>\n\n\n\n
    \"\"
    Fig.1 Older part of the island where we installed the seismometer. <\/figcaption><\/figure>\n\n\n\n
    \"\"
    Fig.3 Flow chart of the storage, processing, and transmission of the data. <\/figcaption><\/figure>\n\n\n\n

    \uff08Volcano Research Center: OHMINATO Takao \uff09<\/p>\n","protected":false},"excerpt":{"rendered":"

    Volcanic activity of Nishinoshima island amongst Bonin Islands, has been continuing since 2013 and the island … Continue reading “\u3010QE\u3011Seismic and infrasound observation in Nishinoshima island”<\/span><\/a><\/p>\n","protected":false},"author":9,"featured_media":2914,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2,4,25,12],"tags":[],"class_list":["post-2910","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news","category-eq","category-gallery","category-whats-new"],"_links":{"self":[{"href":"https:\/\/www.eri.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/posts\/2910"}],"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\/9"}],"replies":[{"embeddable":true,"href":"https:\/\/www.eri.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/comments?post=2910"}],"version-history":[{"count":2,"href":"https:\/\/www.eri.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/posts\/2910\/revisions"}],"predecessor-version":[{"id":2916,"href":"https:\/\/www.eri.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/posts\/2910\/revisions\/2916"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.eri.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/media\/2914"}],"wp:attachment":[{"href":"https:\/\/www.eri.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/media?parent=2910"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.eri.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/categories?post=2910"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.eri.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/tags?post=2910"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}