{"created":"2021-03-01T06:43:45.861066+00:00","id":8371,"links":{},"metadata":{"_buckets":{"deposit":"6ab750bd-7c71-4975-9a1b-f53955144430"},"_deposit":{"id":"8371","owners":[],"pid":{"revision_id":0,"type":"depid","value":"8371"},"status":"published"},"_oai":{"id":"oai:tsukuba.repo.nii.ac.jp:00008371","sets":["3:233:254"]},"author_link":["34815"],"control_number":"8371","item_12_biblio_info_6":{"attribute_name":"書誌情報","attribute_value_mlt":[{"bibliographicIssueDates":{"bibliographicIssueDate":"2004","bibliographicIssueDateType":"Issued"}}]},"item_12_date_granted_46":{"attribute_name":"学位授与年月日","attribute_value_mlt":[{"subitem_dategranted":"2004-03-25"}]},"item_12_degree_grantor_44":{"attribute_name":"学位授与大学","attribute_value_mlt":[{"subitem_degreegrantor":[{"subitem_degreegrantor_language":"ja","subitem_degreegrantor_name":"筑波大学"},{"subitem_degreegrantor_language":"en","subitem_degreegrantor_name":"University of Tsukuba"}],"subitem_degreegrantor_identifier":[{"subitem_degreegrantor_identifier_name":"12102","subitem_degreegrantor_identifier_scheme":"kakenhi"}]}]},"item_12_degree_name_43":{"attribute_name":"取得学位","attribute_value_mlt":[{"subitem_degreename":"博士（理学）"},{"subitem_degreename":"Doctor of Philosophy in Science"}]},"item_12_description_4":{"attribute_name":"抄録","attribute_value_mlt":[{"subitem_description":"Tsunami deposits are indicators of great submarine earthquakes that cannot be decoded from historical earthquake records over the long-term.\nAccurate 14C age determination, discrimination of tsunami deposits from storm deposits and estimation of the source area of tsunamis are fundamental problems for accurate recurrence-interval analyses using ancient tsunami deposits.\nFirstly, in this study, 14C dating, ecological and taphonomic criteria on sample selection are discussed．“True” ages of tsunami deposits are\nexpected from the dating of indigenous and fresh shells ecologically compatible with the depositional environment of the host rocks. Secondly, a “Tsunami depositional sequence model” which identifies the tsunami deposit is proposed for a Holocene buried valley on the southwestern Boso Peninsula, based on depositional structures, high-resolution grainsize\nanalyses and the taphonomy of molluscan shells. This model consists of a stack of depositional units Tna to Tnd which are used to decode the\ntsunami waveform. A typical tsunami has a wave period that is at least 100-times longer than those of storm waves, and includes remarkable edge\nwaves in its middle stage resulting from the reflection of long waves on the continental shelves. A very long wave period of the Holocene tsunami is evidenced by an alternation of hummocky cross-stratified sand units including traction carpet and/or transport lag and mud drapes in Unit Tnb that make up the main part of the tsunami deposit. This cycling of sedimentary structures show repeated arrivals of high-density currents combined with long stagnant stages permitting the deposition of mud drapes.  ･･･","subitem_description_language":"en","subitem_description_type":"Abstract"}]},"item_12_description_45":{"attribute_name":"学位授与年度","attribute_value_mlt":[{"subitem_description":"2003","subitem_description_type":"Other"}]},"item_12_description_5":{"attribute_name":"内容記述","attribute_value_mlt":[{"subitem_description":"Includes bibliographical references","subitem_description_language":"en","subitem_description_type":"Other"},{"subitem_description":"この博士論文は内容の要約のみの公開（または一部非公開）になっています","subitem_description_language":"ja","subitem_description_type":"Other"}]},"item_12_dissertation_number_47":{"attribute_name":"報告番号","attribute_value_mlt":[{"subitem_dissertationnumber":"乙第2022号"}]},"item_access_right":{"attribute_name":"アクセス権","attribute_value_mlt":[{"subitem_access_right":"open access","subitem_access_right_uri":"http://purl.org/coar/access_right/c_abf2"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"藤原, 治","creatorNameLang":"ja"},{"creatorName":"Fujiwara, Osamu","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"34815","nameIdentifierScheme":"WEKO"}]}]},"item_files":{"attribute_name":"ファイル情報","attribute_type":"file","attribute_value_mlt":[{"accessrole":"open_access","date":[{"dateType":"Available","dateValue":"2013-12-18"}],"displaytype":"detail","filename":"B2022.pdf","filesize":[{"value":"179.4 kB"}],"format":"application/pdf","mimetype":"application/pdf","url":{"objectType":"abstract","url":"https://tsukuba.repo.nii.ac.jp/record/8371/files/B2022.pdf"},"version_id":"21c4e8e5-20fd-4a89-8d73-c54f29d2754f"},{"accessrole":"open_access","date":[{"dateType":"Available","dateValue":"2013-12-18"}],"displaytype":"detail","filename":"1.pdf","filesize":[{"value":"12.6 kB"}],"format":"application/pdf","mimetype":"application/pdf","url":{"objectType":"summary","url":"https://tsukuba.repo.nii.ac.jp/record/8371/files/1.pdf"},"version_id":"2b2c3622-b807-4fc1-825d-6323248ebe88"}]},"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":"doctoral thesis","resourceuri":"http://purl.org/coar/resource_type/c_db06"}]},"item_title":"Tsunami depositional sequence model in shallow bay sediments : an example from Holocene drowned valleys on the southern Boso Peninsula, eastern Japan","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"Tsunami depositional sequence model in shallow bay sediments : an example from Holocene drowned valleys on the southern Boso Peninsula, eastern Japan","subitem_title_language":"en"}]},"item_type_id":"12","owner":"1","path":["254"],"pubdate":{"attribute_name":"PubDate","attribute_value":"2007-07-25"},"publish_date":"2007-07-25","publish_status":"0","recid":"8371","relation_version_is_last":true,"title":["Tsunami depositional sequence model in shallow bay sediments : an example from Holocene drowned valleys on the southern Boso Peninsula, eastern Japan"],"weko_creator_id":"1","weko_shared_id":-1},"updated":"2023-05-02T01:31:21.934825+00:00"}