{"created":"2021-03-01T06:51:18.854255+00:00","id":32623,"links":{},"metadata":{"_buckets":{"deposit":"effdd9ad-3da6-4c12-9b0b-1daf5fa13ad0"},"_deposit":{"id":"32623","owner":"1","owners":[],"pid":{"revision_id":0,"type":"depid","value":"32623"},"status":"published"},"_oai":{"id":"oai:repository.dl.itc.u-tokyo.ac.jp:00032623","sets":["80:4535:4639:4647","9:504:4538:4641:4648"]},"author_link":["126325","126326","126327","126328","126321","126322","126323","126324"],"item_4_alternative_title_1":{"attribute_name":"その他のタイトル","attribute_value_mlt":[{"subitem_alternative_title":"Seismic Velocity Structure and Vp/Vs Structure beneath the Northeastern Japan Arc as Inferred from Seismic Traveltime Tomography"}]},"item_4_biblio_info_7":{"attribute_name":"書誌情報","attribute_value_mlt":[{"bibliographicIssueDates":{"bibliographicIssueDate":"2001-07-25","bibliographicIssueDateType":"Issued"},"bibliographicIssueNumber":"1","bibliographicPageEnd":"21","bibliographicPageStart":"13","bibliographicVolumeNumber":"76","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":"Precise estimations both for P- and S-wave velocity structures are essential for understanding the nature of the Earth's interior. We attempted to estimate P- and S-wave velocity structures beneath the northeastern (NE) Japan arc by travel time tomography. We used 169,712 P-wave and 103,993 S-wave arrival times read from waveform data of 4,338 events recorded at more than 200 seismic stations. We estimated the velocity structure in the whole area of NE Japan by setting grids with a horizontal spacing of about 25 km and a vertical spacing of 10-30 km. Low-velocity zones (LVZs) almost parallel to the subducted high-velocity Pacific plate are identified for both P- and S-waves. These LVZs have larger amplitudes for S-wave compared to P-wave. Estimated Vp/Vs ratio is 1.69 on average in the upper crust, 1.75 in the lower crust, and 1.77 in the uppermost mantle. This difference in Vp/Vs ratios among layers are probably caused by differences in the material composing each layer. Our results clearly show LVZs for both P- and S-waves in the crust just beneath active volcanoes. In the uppermost mantle, LVZs are distributed continuously along the volcanic front. These LVZs have smaller Vp/Vs values in the upper crust, while they have larger values in the lower crust and uppermost mantle.","subitem_description_type":"Abstract"}]},"item_4_full_name_3":{"attribute_name":"著者別名","attribute_value_mlt":[{"nameIdentifiers":[{"nameIdentifier":"126325","nameIdentifierScheme":"WEKO"}],"names":[{"name":"Nakajima, Junichi"}]},{"nameIdentifiers":[{"nameIdentifier":"126326","nameIdentifierScheme":"WEKO"}],"names":[{"name":"Matsuzawa, Toru"}]},{"nameIdentifiers":[{"nameIdentifier":"126327","nameIdentifierScheme":"WEKO"}],"names":[{"name":"Hasegawa, Akia"}]},{"nameIdentifiers":[{"nameIdentifier":"126328","nameIdentifierScheme":"WEKO"}],"names":[{"name":"Zhao, Dapeng"}]}]},"item_4_identifier_registration":{"attribute_name":"ID登録","attribute_value_mlt":[{"subitem_identifier_reg_text":"10.15083/0000032623","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":"東北大学大学院理学研究科附属地震・噴火予知研究観測センター"},{"subitem_text_value":"愛媛大学地球深部ダイナミクス研究センター"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"中島, 淳一"}],"nameIdentifiers":[{"nameIdentifier":"126321","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"松澤, 暢"}],"nameIdentifiers":[{"nameIdentifier":"126322","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"長谷川, 昭"}],"nameIdentifiers":[{"nameIdentifier":"126323","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"趙, 大鵬"}],"nameIdentifiers":[{"nameIdentifier":"126324","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":"ji0761002.pdf","filesize":[{"value":"1.4 MB"}],"format":"application/pdf","licensetype":"license_note","mimetype":"application/pdf","url":{"label":"ji0761002.pdf","url":"https://repository.dl.itc.u-tokyo.ac.jp/record/32623/files/ji0761002.pdf"},"version_id":"67637036-588c-4c62-b310-330dc7e71ec8"}]},"item_keyword":{"attribute_name":"キーワード","attribute_value_mlt":[{"subitem_subject":"seismic velocity","subitem_subject_scheme":"Other"},{"subitem_subject":"Vp/Vs ratio","subitem_subject_scheme":"Other"},{"subitem_subject":"microearthquakes","subitem_subject_scheme":"Other"},{"subitem_subject":"low-frequency microearthquakes","subitem_subject_scheme":"Other"},{"subitem_subject":"northeastern Japan arc","subitem_subject_scheme":"Other"}]},"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":"東北日本弧の三次元地震波速度構造とVp/Vs構造","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"東北日本弧の三次元地震波速度構造とVp/Vs構造","subitem_title_language":"ja"}]},"item_type_id":"4","owner":"1","path":["4647","4648"],"pubdate":{"attribute_name":"PubDate","attribute_value":"2008-05-30"},"publish_date":"2008-05-30","publish_status":"0","recid":"32623","relation_version_is_last":true,"title":["東北日本弧の三次元地震波速度構造とVp/Vs構造"],"weko_creator_id":"1","weko_shared_id":-1},"updated":"2022-12-19T05:17:16.716597+00:00"}