{"created":"2023-07-27T06:58:27.683524+00:00","id":56905,"links":{},"metadata":{"_buckets":{"deposit":"d6706ebf-48f7-4ae6-9de9-668a368731b2"},"_deposit":{"created_by":18,"id":"56905","owners":[18],"pid":{"revision_id":0,"type":"depid","value":"56905"},"status":"published"},"_oai":{"id":"oai:kanazawa-u.repo.nii.ac.jp:00056905","sets":["2812:2813:2829"]},"author_link":["99510"],"item_9_biblio_info_8":{"attribute_name":"書誌情報","attribute_value_mlt":[{"bibliographicIssueDates":{"bibliographicIssueDate":"2006-07-10","bibliographicIssueDateType":"Issued"},"bibliographicPageStart":"2p.","bibliographicVolumeNumber":"2003 – 2004","bibliographic_titles":[{"bibliographic_title":"平成16(2004)年度 科学研究費補助金 基盤研究(C) 研究成果報告書概要"},{"bibliographic_title":"2004 Fiscal Year Final Research Report Summary","bibliographic_titleLang":"en"}]}]},"item_9_creator_33":{"attribute_name":"著者別表示","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{}],"nameIdentifiers":[{},{}]}]},"item_9_description_21":{"attribute_name":"抄録","attribute_value_mlt":[{"subitem_description":"伊豆大島内を発震源とする地震波速度変化の検出を目指した実験期間中に,1980年伊豆半島東方沖地震が発生した。本研究ではこの観測データを再解析し,この地震に伴った地震波速度変化の存在とその変化量を明らかにするとともに,地震波速度の応力依存性の空間分布を調べることを目指した。これまでの我々の研究において,観測された地震波速度の時間変化には,海洋潮汐成分と経年的応力蓄積による2つの成分があることがわかっていた。本研究ではそれらを取り除くことで,地震発生後の応力変化に伴ったより微弱な変化成分を抽出した。解析の結果明らかになった変化量は,観測点毎に異なり,波線に沿った平均速度が速くなった観測点と,反対に遅くなった観測点の両方が見られた。特に地震波速度が速くなるという観測は,他の研究で指摘されているような地震の揺れで地表付近の岩石に「緩み」が出来て速度が変化したという考えでは説明できず,地下での速度増加を意味する。地震波速度の応力依存性の空間分布,特に深さ方向の分布を調べるため,波線全体での見かけ速度変化と領域での応力変化量の概算値から,見かけの依存性を求めた。震央距離が長くなるほど波線が地下深部を通過することを利用して,この見かけの依存性と震央距離の関係から依存性の空間分布の推定を行った。見かけ依存性のデータとして,本研究で得られた値だけではなく,これまでに報告されているデータのコンパイルも行った。解析の結果,依存性は表層で1(/MPa)程度の大きさであり,深さとともに急速に減少し,数km深くなる毎に1/10程度に減少することが分かった。","subitem_description_type":"Abstract"},{"subitem_description":"An experiment to detect temporal velocity changes of seismic waves was conducted in 1979-1986 in Kanto and Tokai regions, Japan. Analyzing the travel times observed in the experiment, we have already found that stress variation generated by ocean tides and the tectonic stress accumulation gives rise to the temporal velocity changes in the crust. The Izu-Hanto-Toho-Oki earthquake took place in 1980 within the experiment area. It is supposed that the stress changes associated with the earthquake caused the velocity changes of seismic waves in the crust around the source. We detect the temporal variation of seismic wave velocities, after removing effects of the velocity changes caused by ocean tides and a secular stress accumulation in the crust from the observed travel times. We also investigate the spatial distribution of the stress sensitivity of seismic waves in the crust using the observed velocity changes related the tides, the tectonic stress, and the earthquake. We calculate apparent sensitivities of the velocity to the stress using the observed velocity changes and the relevant stress changes along the wave paths. We compile also apparent stress sensitivities reported by many other researchers. The observed apparent stress sensitivity rapidly decreases with the base line length, which means that the stress sensitivity should sharply decreases with depth. The stress sensitivity is estimated to be about 1 (1/MPa) at the surface and decrease by one order of magnitude every few kilometers.","subitem_description_type":"Abstract"}]},"item_9_description_22":{"attribute_name":"内容記述","attribute_value_mlt":[{"subitem_description":"研究課題/領域番号:15540409, 研究期間(年度):2003 – 2004","subitem_description_type":"Other"},{"subitem_description":"出典：「1980年伊豆半島東方沖地震に伴った地殻内地震波速度変化の研究」研究成果報告書　課題番号15540409\n（KAKEN：科学研究費助成事業データベース（国立情報学研究所））\n（https://kaken.nii.ac.jp/ja/report/KAKENHI-PROJECT-15540409/155404092004kenkyu_seika_hokoku_gaiyo/)を加工して作成","subitem_description_type":"Other"}]},"item_9_description_5":{"attribute_name":"提供者所属","attribute_value_mlt":[{"subitem_description":"金沢大学自然科学研究科","subitem_description_type":"Other"}]},"item_9_identifier_registration":{"attribute_name":"ID登録","attribute_value_mlt":[{"subitem_identifier_reg_text":"10.24517/00063179","subitem_identifier_reg_type":"JaLC"}]},"item_9_relation_28":{"attribute_name":"関連URI","attribute_value_mlt":[{"subitem_relation_name":[{"subitem_relation_name_text":"https://nrid.nii.ac.jp/ja/search/?kw=80109264"}],"subitem_relation_type_id":{"subitem_relation_type_id_text":"https://nrid.nii.ac.jp/ja/search/?kw=80109264","subitem_relation_type_select":"URI"}},{"subitem_relation_name":[{"subitem_relation_name_text":"https://kaken.nii.ac.jp/ja/grant/KAKENHI-PROJECT-15540409/"}],"subitem_relation_type_id":{"subitem_relation_type_id_text":"https://kaken.nii.ac.jp/ja/grant/KAKENHI-PROJECT-15540409/","subitem_relation_type_select":"URI"}},{"subitem_relation_name":[{"subitem_relation_name_text":"https://kaken.nii.ac.jp/ja/report/KAKENHI-PROJECT-15540409/155404092004kenkyu_seika_hokoku_gaiyo/"}],"subitem_relation_type_id":{"subitem_relation_type_id_text":"https://kaken.nii.ac.jp/ja/report/KAKENHI-PROJECT-15540409/155404092004kenkyu_seika_hokoku_gaiyo/","subitem_relation_type_select":"URI"}}]},"item_9_version_type_25":{"attribute_name":"著者版フラグ","attribute_value_mlt":[{"subitem_version_resource":"http://purl.org/coar/version/c_ab4af688f83e57aa","subitem_version_type":"AM"}]},"item_files":{"attribute_name":"ファイル情報","attribute_type":"file","attribute_value_mlt":[{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2021-11-08"}],"displaytype":"detail","filename":"SC-PR-FURUMOTO-M-kaken 2006-2p.pdf","filesize":[{"value":"96.2 kB"}],"format":"application/pdf","licensetype":"license_11","mimetype":"application/pdf","url":{"label":"SC-PR-FURUMOTO-M-kaken 2006-2p.pdf","url":"https://kanazawa-u.repo.nii.ac.jp/record/56905/files/SC-PR-FURUMOTO-M-kaken 2006-2p.pdf"},"version_id":"09d54280-0e94-42d3-b5d8-67f2b01cdd14"}]},"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":"research report","resourceuri":"http://purl.org/coar/resource_type/c_18ws"}]},"item_title":"1980年伊豆半島東方沖地震に伴った地殻内地震波速度変化の研究","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"1980年伊豆半島東方沖地震に伴った地殻内地震波速度変化の研究"},{"subitem_title":"Study on seismic wave velocity changes in the crust associated with the 1980 Izu-Hanto-Toho-Oki Earthquake","subitem_title_language":"en"}]},"item_type_id":"9","owner":"18","path":["2829"],"pubdate":{"attribute_name":"公開日","attribute_value":"2021-11-08"},"publish_date":"2021-11-08","publish_status":"0","recid":"56905","relation_version_is_last":true,"title":["1980年伊豆半島東方沖地震に伴った地殻内地震波速度変化の研究"],"weko_creator_id":"18","weko_shared_id":-1},"updated":"2023-07-27T14:26:05.332909+00:00"}