{"created":"2021-03-01T06:51:30.343812+00:00","id":32795,"links":{},"metadata":{"_buckets":{"deposit":"b71dea03-2d9b-4abd-aa6a-7ee3d03c201d"},"_deposit":{"id":"32795","owner":"1","owners":[],"pid":{"revision_id":0,"type":"depid","value":"32795"},"status":"published"},"_oai":{"id":"oai:repository.dl.itc.u-tokyo.ac.jp:00032795","sets":["80:4535:4737:4741","9:504:4538:4739:4742"]},"author_link":["127600","127601","127602","127603","127604","127595","127596","127597","127598","127599"],"item_4_alternative_title_1":{"attribute_name":"その他のタイトル","attribute_value_mlt":[{"subitem_alternative_title":"Source Process, Characteristics of Associated Seismicity and Seismotectonic Implications of the 1986 Omachi Earthquake of  5.9 in the Northwestern Part of Nagano Prefecture, Central Japan"}]},"item_4_biblio_info_7":{"attribute_name":"書誌情報","attribute_value_mlt":[{"bibliographicIssueDates":{"bibliographicIssueDate":"1989-12-25","bibliographicIssueDateType":"Issued"},"bibliographicIssueNumber":"3","bibliographicPageEnd":"456","bibliographicPageStart":"433","bibliographicVolumeNumber":"64","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":"北部フォッサマグナの糸魚川・静岡構造線に長野盆地西縁断層(善光寺地震断層系)及び千曲川構造線のそれぞれの延長がぶつかる地域において発生した1986年12月30日の地震の震源パラメータや余震活動および先駆的活動の特徴,テクトニクスとの関連について調べた.震源域直上の1臨時観測点を含む近傍の観測点のデータを用いて余震の高精度震源決定を行い,さらに本震の震源についても定常観測点に基づく結果を補正した.この際,深発地震データから推定した走時の観測点補正時間を導入した.本震の深さは5.5kmで,その近傍に集中した余震(狭義の余震)の発生域はN15～20°Wの走向をもち,僅かに西に傾いた,ほぼ垂直な面上にあり,水平に6km,深さ方向に4kmの広さに収まる.この余震分布は初動の押し引きから得られた断層面の一つ(走向N19°W,傾斜角73°,すべり角26°)にほぼ一致する.この狭義の余震の外に点在する広義の余震は東西,南北にそれぞれ20kmの広さに分布する.気象庁の観測点の変位地震計記録の初動P波から推定した震源断層の破壊は,本震の震源付近から,余震が密集している南の領域へ向けて3km/sの速度で伝播した.その全面積は6km2,平均的な変位は75cm.変位の立ち上がり時間は0.5sである.また,地震モーメントは1.3×1024dyne・cm,応力降下は220barである.本震の破壊領域は既存の断層上にはなかったが,広義の余震は,2本の新第三紀層中の断層(小谷-中山断層,持京断層)が会合する地点,両断層に画された東南側の領域一帯,北部の両断層に挾まれた地域や,孤立的に東部の一地点に分布する.活動の範囲は時間とともに,拡大縮小の変化が認められた.最大余震はM3.5(広義の余震)で,本震の大きさに比べ,極めて小さく,余震回数も多くはなかったが,その減衰の定数はp=1で,通常と変わらない.この地震に先行した微小地震活動があった.その震源域は広義の余震の一つのクラスターとほぼ一致する.また,周囲半径100km以内の地震活動が1～2年前から1年後にかけて活発であった.直前の5～9日前には,飛騨山地を隔てた跡津川断層でも,目立った活動があった.大町市付近の系魚川・静岡構造線に沿った地域には,過去にも度々M6程度の地震が発生している.その中で1958年の地震の震央は,今回の地震の活動域にある.このときにも跡津川断層の活動が連動した(1858年飛越地震,M6.9).糸魚川・静岡構造線等を含む広域のネオテクトニクスの枠組みのなかに今回の地震の活動域が位置づけられるとともに,小規模の地殻ブロックの役割も注目される.","subitem_description_type":"Abstract"},{"subitem_description":"A remarkable earthquake of Af 5.9 occurred at 09:38 on December 30, 1986, 10km northeast of Omachi city, Nagano Prefecture. This earthquake was accompanied by precursory microearthquake activity from one year before, at nearly the same place with one of the clustering spots of aftershocks, which is located in the vicinity of the meeting point of the Tertiary faults: the Otari-Nakayama and Mochigyou faults. The historical earthquake of M 5.7 in 1858 took place around this spot. Adjacent to this area, there were two other historical events with magnitude around 6 in 1890 and 1918. Synchronized seismic activity between the Omachi region and the Atotsugawa fault region, about 60 km apart from each other, was found in this 1986 event as in 1858. The surrounding seismicity within 100 km from the epicenter of the 1986 event had been active from several years before.","subitem_description_type":"Abstract"}]},"item_4_full_name_3":{"attribute_name":"著者別名","attribute_value_mlt":[{"nameIdentifiers":[{"nameIdentifier":"127600","nameIdentifierScheme":"WEKO"}],"names":[{"name":"Tsukuda, Tameshige"}]},{"nameIdentifiers":[{"nameIdentifier":"127601","nameIdentifierScheme":"WEKO"}],"names":[{"name":"Sakai, Kaname"}]},{"nameIdentifiers":[{"nameIdentifier":"127602","nameIdentifierScheme":"WEKO"}],"names":[{"name":"Kobayashi, Masaru"}]},{"nameIdentifiers":[{"nameIdentifier":"127603","nameIdentifierScheme":"WEKO"}],"names":[{"name":"Hashikoto, Shin'ichi"}]},{"nameIdentifiers":[{"nameIdentifier":"127604","nameIdentifierScheme":"WEKO"}],"names":[{"name":"Haneda, Toshio"}]}]},"item_4_identifier_registration":{"attribute_name":"ID登録","attribute_value_mlt":[{"subitem_identifier_reg_text":"10.15083/0000032795","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":"佃, 為成"}],"nameIdentifiers":[{"nameIdentifier":"127595","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"酒井, 要"}],"nameIdentifiers":[{"nameIdentifier":"127596","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"小林, 勝"}],"nameIdentifiers":[{"nameIdentifier":"127597","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"橋本, 信一"}],"nameIdentifiers":[{"nameIdentifier":"127598","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"羽田, 敏夫"}],"nameIdentifiers":[{"nameIdentifier":"127599","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":"ji0643002.pdf","filesize":[{"value":"1.4 MB"}],"format":"application/pdf","licensetype":"license_note","mimetype":"application/pdf","url":{"label":"ji0643002.pdf","url":"https://repository.dl.itc.u-tokyo.ac.jp/record/32795/files/ji0643002.pdf"},"version_id":"415fdff9-5a94-4182-996d-cacbaa440ef7"}]},"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":"広義の前震・余震活動を伴った1986年長野県北西部大町付近の地震(M5.9)の震源過程と地震テクトニクス","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"広義の前震・余震活動を伴った1986年長野県北西部大町付近の地震(M5.9)の震源過程と地震テクトニクス","subitem_title_language":"ja"}]},"item_type_id":"4","owner":"1","path":["4741","4742"],"pubdate":{"attribute_name":"PubDate","attribute_value":"2008-05-30"},"publish_date":"2008-05-30","publish_status":"0","recid":"32795","relation_version_is_last":true,"title":["広義の前震・余震活動を伴った1986年長野県北西部大町付近の地震(M5.9)の震源過程と地震テクトニクス"],"weko_creator_id":"1","weko_shared_id":-1},"updated":"2022-12-19T05:17:26.555777+00:00"}