{"created":"2021-03-01T06:51:34.222835+00:00","id":32852,"links":{},"metadata":{"_buckets":{"deposit":"915f3bfb-88d4-4a2d-a297-573f11a62471"},"_deposit":{"id":"32852","owner":"1","owners":[],"pid":{"revision_id":0,"type":"depid","value":"32852"},"status":"published"},"_oai":{"id":"oai:repository.dl.itc.u-tokyo.ac.jp:00032852","sets":["80:4535:4757:4763","9:504:4538:4759:4764"]},"author_link":["128040","128041","128038","128039"],"item_4_alternative_title_1":{"attribute_name":"その他のタイトル","attribute_value_mlt":[{"subitem_alternative_title":"Description of the November 21, 1986 Fissure Eruption on the Caldera Floor of Izu-Oshima Volcano, Japan : Analysis of a Series of Photographs"}]},"item_4_biblio_info_7":{"attribute_name":"書誌情報","attribute_value_mlt":[{"bibliographicIssueDates":{"bibliographicIssueDate":"1987-10-23","bibliographicIssueDateType":"Issued"},"bibliographicIssueNumber":"2","bibliographicPageEnd":"162","bibliographicPageStart":"149","bibliographicVolumeNumber":"62","bibliographic_titles":[{"bibliographic_title":"東京大學地震研究所彙報 = Bulletin of the Earthquake Research Institute, University of Tokyo"}]}]},"item_4_description_13":{"attribute_name":"フォーマット","attribute_value_mlt":[{"subitem_description":"application/pdf","subitem_description_type":"Other"}]},"item_4_description_5":{"attribute_name":"抄録","attribute_value_mlt":[{"subitem_description":"1986年11月21日に伊豆大島のカルデラ床で発生した割れ目噴火について,外輪山北東端と元町郊外で撮影したスチール・フィルムなどをもとに外形上の発達の推移を調べた.三原山の山頂火口から北へ約1km離れたカルデラ床でF1が16時15分に開口し,白煙に続いて灰色の噴煙と赤熱物が噴出した.追いかけるようにF1の南東側にF2が開口した.続いて,16時27分にF3がF2の南東側に,16時40分にF4がF3の南東側にそれぞれ開口した.全体としてみれば,噴火割れ目は北西から南東に,低地から高地に向けて次々に開口した.各割れ目は開口直後に約25m/minの速さで両方向にそれぞれ拡大した.噴火割れ目からの赤熱噴出物は火のカーテンの観を呈した.F1とF2は一列の噴火割れ目になり,それとF3はミ型に雁行した.噴火の勢いは16時50分頃から著しく増大した.火柱の高さはそれまで平均15m/minで増していたが,16時50分過ぎから100m/minの速さに変わった.火柱の高さは17時10分頃に最高の1.6kmに達し,その後しだいに低くなった.火口列の全長はちょうど1.0kmに達した.","subitem_description_type":"Abstract"},{"subitem_description":"On the evening of November 21, 1986, new fissure eruptions occurred on the caldera floor of Izu-Oshima Volcano, Japan. The sequence of their formation is studied on the basis of time-printed photographs which were taken in succession by the authors at close range during the eruption. Shortly after 2 p.m., earthquakes began to increase in number. At 4 : 15 p. m. (7 : 15 a. m. in UT), the first eruption began with the opening of a small fissure from which gas started to rise into the air and then red-hot material spurted up. This outburst was about 1 km north of the summit pit of Mt. Miharayama. At about the same time the second outburst broke out 150 m to the southeast. At 4: 27 p.m., en echelon fissure started to open 110 m farther southeast. During the early stage of eruptions, individual fissures extended, with an average speed of 25 m/ min, both to the northwest and to the southeast across the caldera floor. Red-hot scorias with enormous clouds squirted from many points along fissures in the form of a nearly continuous line of eruptive fountains, producing a curtain of fire. The fountains gradually grew in height with an average speed of 15m/min. By 4: 40 p.m., the curtain of fire reached a height of 440 m and a length of 870 m. During the eruption, deep rumblings emanating from fountains were heard, and numerous earthquakes were felt. At 4: 40 p.m., a new eruption occurred 70 m farther southeast at the flank of Mt. Mihara-yama. On the assumption that the eruptive activity migrated to the southeast due to a rise of local dyke, an average rate of the rise is estimated to be about 3 m/ min. Shortly after 4: 50 p.m., the eruptive phase markedly increased in violence and changed form from fire fountains to some red-hot pillars. The pillars grew rapidly higher with an average velocity of 100 m/min. They reached maximum heights of 1.6 km at 5: 10 p.m. By that time, the fissure zone extended as much as 10 km long and consisted of four individual fissures 140-440 m in length. Lava from fissures spread out to form fan-shaped flows to the north-northwest and to the northeast of the caldera floor. The activity started to decline around 6 p.m. and ceased at about 11p.m., having lasted 7 hours. Although no lives were lost, a series of violent eruptions on November 21 forced all 10,000 islanders to evacuate Izu-Oshima island temporarily.","subitem_description_type":"Abstract"}]},"item_4_full_name_3":{"attribute_name":"著者別名","attribute_value_mlt":[{"nameIdentifiers":[{"nameIdentifier":"128040","nameIdentifierScheme":"WEKO"}],"names":[{"name":"Abe, Katsuyuki"}]},{"nameIdentifiers":[{"nameIdentifier":"128041","nameIdentifierScheme":"WEKO"}],"names":[{"name":"Takahashi, Masayoshi"}]}]},"item_4_identifier_registration":{"attribute_name":"ID登録","attribute_value_mlt":[{"subitem_identifier_reg_text":"10.15083/0000032852","subitem_identifier_reg_type":"JaLC"}]},"item_4_publisher_20":{"attribute_name":"出版者","attribute_value_mlt":[{"subitem_publisher":"東京大学地震研究所"}]},"item_4_source_id_10":{"attribute_name":"書誌レコードID","attribute_value_mlt":[{"subitem_source_identifier":"AN00162258","subitem_source_identifier_type":"NCID"}]},"item_4_source_id_8":{"attribute_name":"ISSN","attribute_value_mlt":[{"subitem_source_identifier":"00408972","subitem_source_identifier_type":"ISSN"}]},"item_4_subject_15":{"attribute_name":"日本十進分類法","attribute_value_mlt":[{"subitem_subject":"453","subitem_subject_scheme":"NDC"}]},"item_4_text_21":{"attribute_name":"出版者別名","attribute_value_mlt":[{"subitem_text_value":"Earthquake Research Institute, University of Tokyo"}]},"item_4_text_4":{"attribute_name":"著者所属","attribute_value_mlt":[{"subitem_text_value":"地震研究所"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"阿部, 勝征"}],"nameIdentifiers":[{"nameIdentifier":"128038","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"高橋, 正義"}],"nameIdentifiers":[{"nameIdentifier":"128039","nameIdentifierScheme":"WEKO"}]}]},"item_files":{"attribute_name":"ファイル情報","attribute_type":"file","attribute_value_mlt":[{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2017-06-26"}],"displaytype":"detail","filename":"ji0622003.pdf","filesize":[{"value":"1.3 MB"}],"format":"application/pdf","licensetype":"license_note","mimetype":"application/pdf","url":{"label":"ji0622003.pdf","url":"https://repository.dl.itc.u-tokyo.ac.jp/record/32852/files/ji0622003.pdf"},"version_id":"90516832-faca-46aa-af34-51443cc9ad0d"}]},"item_language":{"attribute_name":"言語","attribute_value_mlt":[{"subitem_language":"jpn"}]},"item_resource_type":{"attribute_name":"資源タイプ","attribute_value_mlt":[{"resourcetype":"departmental bulletin paper","resourceuri":"http://purl.org/coar/resource_type/c_6501"}]},"item_title":"伊豆大島カルデラ床での割れ目噴火(1986年11月21日)の推移 : 写真解析による調査","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"伊豆大島カルデラ床での割れ目噴火(1986年11月21日)の推移 : 写真解析による調査","subitem_title_language":"ja"}]},"item_type_id":"4","owner":"1","path":["4763","4764"],"pubdate":{"attribute_name":"PubDate","attribute_value":"2008-05-30"},"publish_date":"2008-05-30","publish_status":"0","recid":"32852","relation_version_is_last":true,"title":["伊豆大島カルデラ床での割れ目噴火(1986年11月21日)の推移 : 写真解析による調査"],"weko_creator_id":"1","weko_shared_id":-1},"updated":"2022-12-19T05:17:28.590236+00:00"}