{"created":"2021-03-01T06:51:50.327465+00:00","id":33095,"links":{},"metadata":{"_buckets":{"deposit":"bc409a86-51bd-48bd-8cdc-6fba0ffb1195"},"_deposit":{"id":"33095","owner":"1","owners":[],"pid":{"revision_id":0,"type":"depid","value":"33095"},"status":"published"},"_oai":{"id":"oai:repository.dl.itc.u-tokyo.ac.jp:00033095","sets":["80:4535:4837:4838","9:504:4538:4839:4840"]},"author_link":["129077","129076"],"item_4_alternative_title_1":{"attribute_name":"その他のタイトル","attribute_value_mlt":[{"subitem_alternative_title":"波形解析からみた伊豆半島川奈崎冲群発地震の活動様式"}]},"item_4_biblio_info_7":{"attribute_name":"書誌情報","attribute_value_mlt":[{"bibliographicIssueDates":{"bibliographicIssueDate":"1980-03-31","bibliographicIssueDateType":"Issued"},"bibliographicIssueNumber":"3","bibliographicPageEnd":"462","bibliographicPageStart":"441","bibliographicVolumeNumber":"54","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":"The earthquake swarm activity which occurred in the Kawanazaki-oki area of the Izu peninsula is studied through the analysis of waveforms. The earthquakes are usually concentrated within a brief time interval (e.g., 1 hour); they usually share a similar waveform; and the arrival times for certain isolated waves, measured from the P-wave onset of their events, are the same within a deviation of 0.05 sec (0.02 sec for the events with similar size). Similar behavior, but with different waveforms, can be seen for the earthquakes which occurred in another time interval. Nineteen event groups, with their own spectral characteristics, are obtained for 264 earthquakes selected from 365 earthquakes. In addition, the corner frequency of the source spectrum in a given event group is constant, that is independent of earthquake magnitudes between 1.5 and 3. From the points of waveform and spectrum, we suggest that there exist numerous cracks and faults bounded by strong barriers, and the earthquakes in a given event group are occurring over the same fault as repeated stick-slip.","subitem_description_type":"Abstract"},{"subitem_description":"1978年11月24日頃より,伊豆半島,川奈崎沖において地震活動が活発化し約20日間続いた.この地震は,その活動状況からみて典型的な群発地震であった.今回これらの地震について,地震波動の波形並びにスペクトル解析から,その活動様式についていくつかの特徴ある結果を得た.主な結果は次の通りである.(1)大山観測所上下動成分の早送り記録(25mm/sec)の重ね合せにより波形について調べた結果,ある限られた時間帯(例えば,1時間)に発生する群発地震の波形は非常に似ており,いわゆる\"\"相似地震\"\"によって構成されていることが解った.更にこのような傾向は,互いに方向の異なる他の観測所の記録についても同じである.(2)一連の相似地震にはS波を含むいくつかの孤立波形が見られる.初動から測ったそれぞれの孤立波形の到達時刻は0.05secの範囲内で一致し,特に同じ大きさを持つ地震についてみると,初動から20sec 後のCoda waveについても同様の傾向が見られる.(3)S波についてのスペクトル解析から,相似地震のCorner frequencyはM=1.5-3の間で略一定である.合計365個(M≧1.5)の観測された地震のうち,相似波形を持つ地震数5個以上のものを1組の相似地震群とすると,全体として約72%のものが,いずれかの組に属する相似地震であり,計19種類の相似地震群が得られた.(1),(2),(3)の結果からみて,それぞれの相似地震は,ある限られたせまい範囲,例えば同じ断層面上で繰返し発生していることが推定され,又19種類の相似地震の存在は群発地震の活動域が順次移動していったことを示すものであろう.","subitem_description_type":"Abstract"}]},"item_4_full_name_3":{"attribute_name":"著者別名","attribute_value_mlt":[{"nameIdentifiers":[{"nameIdentifier":"129077","nameIdentifierScheme":"WEKO"}],"names":[{"name":"辻浦, 賢"}]}]},"item_4_identifier_registration":{"attribute_name":"ID登録","attribute_value_mlt":[{"subitem_identifier_reg_text":"10.15083/0000033095","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":"Tsujiura, Masaru"}],"nameIdentifiers":[{"nameIdentifier":"129076","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":"ji0543002.pdf","filesize":[{"value":"1.2 MB"}],"format":"application/pdf","licensetype":"license_note","mimetype":"application/pdf","url":{"label":"ji0543002.pdf","url":"https://repository.dl.itc.u-tokyo.ac.jp/record/33095/files/ji0543002.pdf"},"version_id":"db000ef5-7e78-4fec-99d2-dc284abb3086"}]},"item_language":{"attribute_name":"言語","attribute_value_mlt":[{"subitem_language":"eng"}]},"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":"Mechanism of the Earthquake Swarm Activity in the Kawanazaki-oki, Izu Peninsula, as Inferred from the Analysis of Seismic Waveforms","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"Mechanism of the Earthquake Swarm Activity in the Kawanazaki-oki, Izu Peninsula, as Inferred from the Analysis of Seismic Waveforms","subitem_title_language":"en"}]},"item_type_id":"4","owner":"1","path":["4838","4840"],"pubdate":{"attribute_name":"PubDate","attribute_value":"2008-05-30"},"publish_date":"2008-05-30","publish_status":"0","recid":"33095","relation_version_is_last":true,"title":["Mechanism of the Earthquake Swarm Activity in the Kawanazaki-oki, Izu Peninsula, as Inferred from the Analysis of Seismic Waveforms"],"weko_creator_id":"1","weko_shared_id":-1},"updated":"2022-12-19T04:08:55.059289+00:00"}