{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,30]],"date-time":"2026-04-30T07:39:25Z","timestamp":1777534765533,"version":"3.51.4"},"reference-count":15,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2009,11,18]],"date-time":"2009-11-18T00:00:00Z","timestamp":1258502400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Sagami Bay is an active tectonic area in Japan. In 1993, a real-time deep sea floor observatory was deployed at 1,175 m depth about 7 km off Hatsushima Island, Sagami Bay to monitor seismic activities and other geophysical phenomena. Video cameras monitored biological activities associated with tectonic activities. The observation system was renovated completely in 2000. An ocean bottom electromagnetic meter (OBEM), an ocean bottom differential pressure gauge (DPG) system, and an ocean bottom gravity meter (OBG) were installed January 2005; operations began in February of that year. An earthquake (M5.4) in April 2006, generated a submarine landslide that reached the Hatsushima Observatory, moving some sensors. The video camera took movies of mudflows; OBEM and other sensors detected distinctive changes occurring with the mudflow. Although the DPG and OBG were recovered in January 2008, the OBEM continues to obtain data.<\/jats:p>","DOI":"10.3390\/s91109241","type":"journal-article","created":{"date-parts":[[2009,11,19]],"date-time":"2009-11-19T02:20:40Z","timestamp":1258597240000},"page":"9241-9254","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Trial of Multidisciplinary Observation at an Expandable Sub-Marine Cabled Station \u201cOff-Hatsushima Island Observatory\u201d in Sagami Bay, Japan"],"prefix":"10.3390","volume":"9","author":[{"given":"Takafumi","family":"Kasaya","sequence":"first","affiliation":[{"name":"Japan Agency for Marine\u2013Earth Science and Technology (JAMSTEC), 2-15, Natsushima-cho, Yokosuka, Kanagawa, 237-0061, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kyohiko","family":"Mitsuzawa","sequence":"additional","affiliation":[{"name":"Japan Agency for Marine\u2013Earth Science and Technology (JAMSTEC), 2-15, Natsushima-cho, Yokosuka, Kanagawa, 237-0061, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tada-nori","family":"Goto","sequence":"additional","affiliation":[{"name":"Japan Agency for Marine\u2013Earth Science and Technology (JAMSTEC), 2-15, Natsushima-cho, Yokosuka, Kanagawa, 237-0061, Japan"},{"name":"Department of Civil and Earth Resources Engineering, Graduate School of Engineering, Kyoto University, Kyoto daigaku-Katsura, Nishikyo-ku, Kyoto, 615-8540, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ryoichi","family":"Iwase","sequence":"additional","affiliation":[{"name":"Japan Agency for Marine\u2013Earth Science and Technology (JAMSTEC), 2-15, Natsushima-cho, Yokosuka, Kanagawa, 237-0061, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Keizo","family":"Sayanagi","sequence":"additional","affiliation":[{"name":"Institute of Oceanic Research and Development, Tokai University, 3-20-1, Orido, Shimizu-ku, Shizuoka-shi, 424-8610, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eiichiro","family":"Araki","sequence":"additional","affiliation":[{"name":"Japan Agency for Marine\u2013Earth Science and Technology (JAMSTEC), 2-15, Natsushima-cho, Yokosuka, Kanagawa, 237-0061, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kenichi","family":"Asakawa","sequence":"additional","affiliation":[{"name":"Japan Agency for Marine\u2013Earth Science and Technology (JAMSTEC), 2-15, Natsushima-cho, Yokosuka, Kanagawa, 237-0061, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hitoshi","family":"Mikada","sequence":"additional","affiliation":[{"name":"Department of Civil and Earth Resources Engineering, Graduate School of Engineering, Kyoto University, Kyoto daigaku-Katsura, Nishikyo-ku, Kyoto, 615-8540, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tomoki","family":"Watanabe","sequence":"additional","affiliation":[{"name":"Marine Works Japan Ltd. \/ c\/o JAMSEC YES, 3173-25, Syowa-machi, Kanazawa-ku, Yokohama, Kanagawa, 236-0001, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ichiro","family":"Takahashi","sequence":"additional","affiliation":[{"name":"Marine Works Japan Ltd. \/ c\/o JAMSEC YES, 3173-25, Syowa-machi, Kanazawa-ku, Yokohama, Kanagawa, 236-0001, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Toshiyasu","family":"Nagao","sequence":"additional","affiliation":[{"name":"Institute of Oceanic Research and Development, Tokai University, 3-20-1, Orido, Shimizu-ku, Shizuoka-shi, 424-8610, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2009,11,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"263","DOI":"10.1016\/S0031-9201(98)00107-1","article-title":"Preliminary results of a three-year continuous observation by a deep seafloor observatory in Sagami Bay, central Japan","volume":"108","author":"Momma","year":"1998","journal-title":"Phys. Earth Planet. Int."},{"key":"ref_2","first-page":"185","article-title":"Renewal of \u201cReal-time deep seafloor observatory off Hatsushima Island in Sagami Bay\u201d\u2013Toward the development of \u201cnext-generational\u201d real-time deep seafloor observatory","volume":"18","author":"Iwase","year":"2001","journal-title":"JAMSTEC Deep Sea Res."},{"key":"ref_3","unstructured":"Iwase, R., Asakawa, K., Mikada, H., Goto, T., Mitsuzawa, K., Kawaguchi, K., Hirata, K., and Kaiho, Y. Off Hatsushima Island observatory in Sagami Bay: Multidisciplinary long term observation at cold seepage site with underwater mateable connectors for future use. Tokyo, Japan."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"170","DOI":"10.1109\/JOE.2002.1002471","article-title":"Real-time geophysical measurements on the deep seafloor using submarine cable in the southern Kurile subduction zone","volume":"27","author":"Hirata","year":"2002","journal-title":"IEEE J. Ocean. 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