Pub Date : 2021-01-01DOI: 10.2343/geochemj.gj22001
Kenta Asahina, T. Nakajima, Koji U. Takahashi, Miyuki Kobayashi, Y. Hanamura
{"title":"Spatio-temporal changes in the depositional environment of Miocene organic rich mudstones in the Akita Basin deduced from biomarker analysis","authors":"Kenta Asahina, T. Nakajima, Koji U. Takahashi, Miyuki Kobayashi, Y. Hanamura","doi":"10.2343/geochemj.gj22001","DOIUrl":"https://doi.org/10.2343/geochemj.gj22001","url":null,"abstract":"","PeriodicalId":12682,"journal":{"name":"Geochemical Journal","volume":"126 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88688547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Constraints of the geochemical characteristics of apatite on uranium mineralization in a uraninite-rich quartz vein in the Haita area of the Kangdian region, China","authors":"Minghui Yin, Zhengqi Xu, Hao Song, Chengjiang Zhang, Suheng Zhang, Jianmin Tian, Hu Guo","doi":"10.2343/geochemj.2.0638","DOIUrl":"https://doi.org/10.2343/geochemj.2.0638","url":null,"abstract":"","PeriodicalId":12682,"journal":{"name":"Geochemical Journal","volume":"77 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82577965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Y. Matsui, Wataru Fujisaki, J. Torimoto, Keiko Tanaka, M. Nishizawa, M. Yamamoto, S. Kawagucci, Y. Shimane, Mika Tei, K. Uematsu, Akihiro Tame, Y. Kawahito, T. Kameda
Fujisaki et al., 2016, 2018, 2019). To prepare the samples for OC analysis with EA-IRMS, coexisting carbonate minerals need to be removed to ensure accurate and precise quantification. For example, for a sediment sample that contains 1 wt% OC and 1 wt% carbonate derived C, the total C would be 2 wt% and the δCtotal C of the non-acidified (non-decalcified) sample would be about –11‰, since the δCorg of a typical pelagic sediment is about –22‰ while the δCcarbonate of benthic foraminifera is about 0‰. In this case, the δCtotal C value cannot be used as a proxy for the δCorg. Several approaches have been proposed for removing carbonate minerals, such as acid treatment using either hydrochloric, phosphoric, or sulfurous acid (Al-Aasm et al., 1990; Brodie et al., 2011) and the stepwise combustion method (Uchida et al., 2008). Acid treatment can be Gold-coated silver capsule for elemental analyzer-isotope ratio mass spectrometer: Robust against pretreatment of rock material for organic carbon and δ13C analyses
Fujisaki et al., 2016, 2018, 2019)。为了准备样品进行EA-IRMS OC分析,需要去除共存的碳酸盐矿物,以确保准确和精确的定量。例如,对于含有1 wt% OC和1 wt%碳酸盐衍生C的沉积物样品,总C为2 wt%,而非酸化(非脱钙化)样品的δCtotal C约为-11‰,因为典型的远洋沉积物的δ cgc约为-22‰,而底栖有孔虫的δ c酸盐约为0‰。在这种情况下,δCtotal C值不能作为δCorg的代表。已经提出了几种去除碳酸盐矿物的方法,例如使用盐酸、磷酸或硫酸进行酸处理(al - aasm等人,1990年;Brodie et al., 2011)和逐步燃烧法(Uchida et al., 2008)。酸处理可用于元素分析仪-同位素比质谱仪的金包银胶囊:对岩石材料的预处理具有很强的抗氧化性,可用于有机碳和δ13C分析
{"title":"Gold-coated silver capsule for elemental analyzer-isotope ratio mass spectrometer: Robust against pretreatment of rock material for organic carbon and δ13C analyses","authors":"Y. Matsui, Wataru Fujisaki, J. Torimoto, Keiko Tanaka, M. Nishizawa, M. Yamamoto, S. Kawagucci, Y. Shimane, Mika Tei, K. Uematsu, Akihiro Tame, Y. Kawahito, T. Kameda","doi":"10.2343/geochemj.2.0626","DOIUrl":"https://doi.org/10.2343/geochemj.2.0626","url":null,"abstract":"Fujisaki et al., 2016, 2018, 2019). To prepare the samples for OC analysis with EA-IRMS, coexisting carbonate minerals need to be removed to ensure accurate and precise quantification. For example, for a sediment sample that contains 1 wt% OC and 1 wt% carbonate derived C, the total C would be 2 wt% and the δCtotal C of the non-acidified (non-decalcified) sample would be about –11‰, since the δCorg of a typical pelagic sediment is about –22‰ while the δCcarbonate of benthic foraminifera is about 0‰. In this case, the δCtotal C value cannot be used as a proxy for the δCorg. Several approaches have been proposed for removing carbonate minerals, such as acid treatment using either hydrochloric, phosphoric, or sulfurous acid (Al-Aasm et al., 1990; Brodie et al., 2011) and the stepwise combustion method (Uchida et al., 2008). Acid treatment can be Gold-coated silver capsule for elemental analyzer-isotope ratio mass spectrometer: Robust against pretreatment of rock material for organic carbon and δ13C analyses","PeriodicalId":12682,"journal":{"name":"Geochemical Journal","volume":"1 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86478997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bibhuti Gogoi, G. Hazarika, H. Chauhan, Sowrav Saikia
{"title":"Role of viscous swirling in the formation of magnetite ocelli or fleck structure in the migmatites of Shillong Plateau Gneissic Complex, eastern India","authors":"Bibhuti Gogoi, G. Hazarika, H. Chauhan, Sowrav Saikia","doi":"10.2343/geochemj.2.0643","DOIUrl":"https://doi.org/10.2343/geochemj.2.0643","url":null,"abstract":"","PeriodicalId":12682,"journal":{"name":"Geochemical Journal","volume":"31 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79014234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Application of handheld XRF on Ta-Nb-Sn-W ore: Factory calibration or user calibration?","authors":"A. Somarin, Li Zhou, Ingo Steinhage","doi":"10.2343/geochemj.2.0624","DOIUrl":"https://doi.org/10.2343/geochemj.2.0624","url":null,"abstract":"","PeriodicalId":12682,"journal":{"name":"Geochemical Journal","volume":"1 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89464211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Origin of porphyritic texture by magma mixing in the andesitic rocks of Ghansura Rhyolite Dome from the Bathani volcano-sedimentary sequence, Eastern India","authors":"Bibhuti Gogoi, G. Hazarika, H. Chauhan","doi":"10.2343/geochemj.2.0613","DOIUrl":"https://doi.org/10.2343/geochemj.2.0613","url":null,"abstract":"","PeriodicalId":12682,"journal":{"name":"Geochemical Journal","volume":"34 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87545755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}