{"created":"2023-07-27T06:26:39.974004+00:00","id":10478,"links":{},"metadata":{"_buckets":{"deposit":"49237860-e59c-4981-b2aa-c1234de9eb6a"},"_deposit":{"created_by":3,"id":"10478","owners":[3],"pid":{"revision_id":0,"type":"depid","value":"10478"},"status":"published"},"_oai":{"id":"oai:kanazawa-u.repo.nii.ac.jp:00010478","sets":["934:935:937"]},"author_link":["15885","14170","15884","152"],"item_4_biblio_info_8":{"attribute_name":"書誌情報","attribute_value_mlt":[{"bibliographicIssueDates":{"bibliographicIssueDate":"2010-01-01","bibliographicIssueDateType":"Issued"},"bibliographicIssueNumber":"10","bibliographicPageEnd":"543","bibliographicPageStart":"523","bibliographicVolumeNumber":"116","bibliographic_titles":[{"bibliographic_title":"地質学雑誌 = Journal of the Geological Society of Japan"}]}]},"item_4_description_21":{"attribute_name":"抄録","attribute_value_mlt":[{"subitem_description":"Ostracoda, a crustacean group, have valves composed of low-magnesium calcite. The magnesium/calcium (Mg/Ca) and strontium/calcium (Sr/Ca) ratios of fossil ostracodes have been used as indicators of the paleoenvironment. The Mg/Ca ratios and partition coefficients of marine ostracodes generally correlate with the water temperature of the ostracode habitat, and the Mg/Ca and Sr/Ca ratios of freshwater ostracodes have been used as a proxy for water chemistry. We reviewed previous studies on the Mg/Ca and Sr/Ca ratios of ostracode valves and obtained the following findings. (1) Diagenesis is likely to affect the Mg/Ca and Sr/Ca ratios of subfossil and fossil valves ; however, it is difficult to assess the degree of diagenetic alteration using methods developed in previous studies, such as that based on the visual preservation index (VPI) . Our statistic analysis, using published data, revealed no significant correlation between VPI and the Mg/Ca or Sr/Ca ratios of artificial dissolved specimens. (2) The partition coefficients of Mg/Ca and Sr/Ca ratios vary with the taxa, habitat, and phyletic group. Cypridoidea have statistically higher Mg/Ca and lower Sr/Ca partition coefficients than do Bairdioidea and Cytheroidea. Compared with marine taxa, freshwater taxa have more variable partition coefficients. The Mg/Ca partition coefficient of marine ostracodes is clearly dependent on the phyletic group at the family level. (3) The Mg/Ca and Sr/Ca partition coefficients are independent of sex but may depend on ontogenic stage. (4) The variable nature of partition coefficients in marine species indicates that Mg/Ca thermometers have an error of ±2–4°C. (5) Spatial variations in Mg concentration within an individual valve have an effect on the Mg/Ca ratio of the whole valve. The accuracy of Mg/Ca and Sr/Ca ratios as proxies for temperature and water chemistry would be improved if the effects of diagenesis and spatial heterogeneity are evaluated quantitatively and if the partition coefficients of various taxa are available. 微小甲殻類の一種である貝形虫は低マグネシウム方解石の殻を持っており，この殻の微量元素量および，その比は古環境指標として利用されている．一般に海棲の貝形虫の殻のMg/Ca比は，生息場の水温と強い相関があり，淡水棲の貝形虫の殻のMg/Ca比およびSr/Ca比は生息場のMg, Sr量を反映している．既存の研究を総括した結果，次のことが明らかになった．1）続成作用による殻のMg/Ca比およびSr/Ca比の変化を評価する方法は確立されていない．2）殻のMg/Ca比およびSr/Ca比の分配係数の範囲は分類群，生息場，系統によって異なる．3）これらの分配係数の範囲は種内の成長ステージによって異なる場合がある．4）海棲種のMg/Ca比の分配係数から見積もられる水温は約2～4℃の誤差を伴う．5）殻内の微小領域でのMgの分布の不均一性は殻全体のMg/Ca比に影響する．貝形虫殻のMg/Ca比，Sr/Ca比をより精密な環境指標として確立するためには，生息環境のMg/Ca比，Sr/Ca比，続成作用や試料の前処理の厳密な評価，およびより多くの分類群のデータが必要である．","subitem_description_type":"Abstract"}]},"item_4_publisher_17":{"attribute_name":"出版者","attribute_value_mlt":[{"subitem_publisher":"日本地質学会 = Geological Society of Japan"}]},"item_4_relation_12":{"attribute_name":"DOI","attribute_value_mlt":[{"subitem_relation_type":"isIdenticalTo","subitem_relation_type_id":{"subitem_relation_type_id_text":"10.5575/geosoc.116.523","subitem_relation_type_select":"DOI"}}]},"item_4_relation_28":{"attribute_name":"関連URI","attribute_value_mlt":[{"subitem_relation_type_id":{"subitem_relation_type_id_text":"http://www.geosociety.jp/","subitem_relation_type_select":"URI"}},{"subitem_relation_type_id":{"subitem_relation_type_id_text":"https://www.jstage.jst.go.jp/browse/geosoc","subitem_relation_type_select":"URI"}}]},"item_4_rights_23":{"attribute_name":"権利","attribute_value_mlt":[{"subitem_rights":"Copyright © 日本地質学会 Geological Society of Japan"}]},"item_4_source_id_11":{"attribute_name":"NCID","attribute_value_mlt":[{"subitem_source_identifier":"AN00141768","subitem_source_identifier_type":"NCID"}]},"item_4_source_id_9":{"attribute_name":"ISSN","attribute_value_mlt":[{"subitem_source_identifier":"0016-7630","subitem_source_identifier_type":"ISSN"}]},"item_4_version_type_25":{"attribute_name":"著者版フラグ","attribute_value_mlt":[{"subitem_version_resource":"http://purl.org/coar/version/c_970fb48d4fbd8a85","subitem_version_type":"VoR"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"森下, 知晃"}],"nameIdentifiers":[{},{},{}]},{"creatorNames":[{"creatorName":"山口, 龍彦"}],"nameIdentifiers":[{}]},{"creatorNames":[{"creatorName":"眞柴, 久和"}],"nameIdentifiers":[{}]},{"creatorNames":[{"creatorName":"神谷, 隆宏"}],"nameIdentifiers":[{},{},{},{}]}]},"item_files":{"attribute_name":"ファイル情報","attribute_type":"file","attribute_value_mlt":[{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2017-10-03"}],"displaytype":"detail","filename":"SC-PR-MORISHITA-T-523.pdf","filesize":[{"value":"2.2 MB"}],"format":"application/pdf","licensetype":"license_note","mimetype":"application/pdf","url":{"label":"SC-PR-MORISHITA-T-523.pdf","url":"https://kanazawa-u.repo.nii.ac.jp/record/10478/files/SC-PR-MORISHITA-T-523.pdf"},"version_id":"540fd3b3-6944-43bd-b9fd-d5cd9358e931"}]},"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":"journal article","resourceuri":"http://purl.org/coar/resource_type/c_6501"}]},"item_title":"貝形虫の殻のMg/Ca比, Sr/Ca比による古環境推定の現状と問題点","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"貝形虫の殻のMg/Ca比, Sr/Ca比による古環境推定の現状と問題点"},{"subitem_title":"A review of the utility of Mg/Ca and Sr/Ca ratios of ostracode valves as a tool for paleoenvironmental reconstructions","subitem_title_language":"en"}]},"item_type_id":"4","owner":"3","path":["937"],"pubdate":{"attribute_name":"公開日","attribute_value":"2017-10-03"},"publish_date":"2017-10-03","publish_status":"0","recid":"10478","relation_version_is_last":true,"title":["貝形虫の殻のMg/Ca比, Sr/Ca比による古環境推定の現状と問題点"],"weko_creator_id":"3","weko_shared_id":-1},"updated":"2023-07-28T01:40:19.558090+00:00"}