Geochemical Journal最新文献_第4页

Theoretical Calculation of Equilibrium Cadmium Isotope Fractionation Factors between Cadmium-bearing sulfides and aqueous solutions 含镉硫化物与水溶液中镉同位素平衡分馏因子的理论计算

IF 0.8 4区地球科学

Geochemical Journal Pub Date : 2022-01-01 DOI: 10.2343/geochemj.gj22018

Jixi Zhang, Renxue Shi

{"title":"Theoretical Calculation of Equilibrium Cadmium Isotope Fractionation Factors between Cadmium-bearing sulfides and aqueous solutions","authors":"Jixi Zhang, Renxue Shi","doi":"10.2343/geochemj.gj22018","DOIUrl":"https://doi.org/10.2343/geochemj.gj22018","url":null,"abstract":"7 In this study, the equilibrium isotope fractionation factors between Cd-bearing 8 aqueous solutions and minerals were predicted. The theoretical method used to calculate 9 the Cd isotope fractionation factors is the first-principle quantum chemistry method (Cd: 10 LANL2DZ, other atoms: 6-311+G(d, P)). Reduced partition function ratios (RPFRs) of 11 Cd-bearing minerals (Greenockite and Sphalerite) were modeled by the method of the 12 volume variable cluster model (VVCM). The theoretical method of “water-droplet 13 method” is used to simulate the solvation effect of different Cd-bearing aqueous solutions. 14 The results show that, in most cases, the Cd-bearing aqueous solutions are enriched in 15 114 Cd relative to Greenockite. The Cd isotope fractionation factors between Cd-bearing 16 aqueous solutions and Greenockite are in the range of 0.433- 0.083 (100℃) . And the Cd 17 isotope fractionations between different Cd-bearing species are believed to be widespread. 18 Cd isotope fractionation factors between different reservoirs are of great theoretical 19 significance to many geochemical processes such as surficial geochemical process and 20 ore-forming process. These theoretical parameters are studied systematically and 21 carefully in this study. 22","PeriodicalId":12682,"journal":{"name":"Geochemical Journal","volume":"36 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91309021","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}

引用次数: 0

An effect of variations in relative sensitivity factors on Al-Mg systematics of Ca-Al-rich inclusions in meteorites with secondary ion mass spectrometry 相对敏感因子变化对陨石富钙铝包裹体Al-Mg系统的二次离子质谱分析影响

IF 0.8 4区地球科学

Geochemical Journal Pub Date : 2021-01-01 DOI: 10.2343/geochemj.2.0634

N. Kawasaki, Changkun Park, S. Wakaki, Hwayoung Kim, S. Park, T. Yoshimura, K. Nagaishi, Hyun Na Kim, N. Sakamoto, H. Yurimoto

{"title":"An effect of variations in relative sensitivity factors on Al-Mg systematics of Ca-Al-rich inclusions in meteorites with secondary ion mass spectrometry","authors":"N. Kawasaki, Changkun Park, S. Wakaki, Hwayoung Kim, S. Park, T. Yoshimura, K. Nagaishi, Hyun Na Kim, N. Sakamoto, H. Yurimoto","doi":"10.2343/geochemj.2.0634","DOIUrl":"https://doi.org/10.2343/geochemj.2.0634","url":null,"abstract":"significant variations in (Al/Al)0, implying that thermal processes of condensation and melting for CAI formation occurred contemporaneously and continued for ~0.4 Myr at the very beginning of Solar System formation, under the assumption of homogeneous distributions of 26Al in the forming region (Kawasaki et al., 2020). Among the data available, an example of the smallest analytical errors in (Al/Al)0 for CAIs has been obtained from a fluffy Type A CAI from Vigarano, with (Al/Al)0 = (4.703 ± 0.082) × 10 –5 (Kawasaki et al., 2019); the relative error is 1.7%. (Al/Al)0 for CAIs is determined from the slope of the regression line for CAI mineral data on the Al-Mg evolution diagram (27Al/24Mg vs. radiogenic excess of 26Mg, 26Mg*) for each CAI. 26Mg* values for CAI minerals are accurately determined with SIMS by correcting both natural mass-dependent fractionation and instrumental mass fractionation (IMF) of SIMS for Mg-isotopes (Itoh et al., 2008; Kita et al., 2012; Kawasaki et al., 2017). On the other hand, relative An effect of variations in relative sensitivity factors on Al-Mg systematics of Ca-Al-rich inclusions in meteorites with secondary ion mass spectrometry","PeriodicalId":12682,"journal":{"name":"Geochemical Journal","volume":"137 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84827294","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}

引用次数: 1

A record of 241Am, 236U, 238U, 239Pu, 240Pu, 134Cs and 137Cs in surface seawater and 241Am in aerosols shortly after the FDNPP incident occurred FDNPP事故发生后不久，表层海水中记录了241Am、236U、238U、239Pu、240Pu、134Cs和137Cs，气溶胶中记录了241Am

IF 0.8 4区地球科学

Geochemical Journal Pub Date : 2021-01-01 DOI: 10.2343/geochemj.2.0615

引用次数: 2

Preliminary report on small-mass graphitization for radiocarbon dating using EA-AGE3 at JAEA-AMS-TONO 用EA-AGE3在JAEA-AMS-TONO进行小质量石墨化放射性碳测年的初步报告

IF 0.8 4区地球科学

Geochemical Journal Pub Date : 2021-01-01 DOI: 10.2343/geochemj.2.0629

Takahiro Watanabe, N. Fujita, A. Matsubara, M. Miyake, T. Nishio, C. Ishizaka, Y. Saito-Kokubu

{"title":"Preliminary report on small-mass graphitization for radiocarbon dating using EA-AGE3 at JAEA-AMS-TONO","authors":"Takahiro Watanabe, N. Fujita, A. Matsubara, M. Miyake, T. Nishio, C. Ishizaka, Y. Saito-Kokubu","doi":"10.2343/geochemj.2.0629","DOIUrl":"https://doi.org/10.2343/geochemj.2.0629","url":null,"abstract":"In the case of AMS 14C measurements, the CO2 gas purification procedure from solid samples by the vacuum glass line has been performed as a traditional preparation technique. In some cases (e.g., Morgenroth et al., 2000; Yoneda et al., 2004), sample combustion and gaseous CO2 separation procedures were automatically performed by the EA. Subsequently, the automated graphitization equipment (AGE) was developed by IonPlus AG (Němec et al., 2010; Wacker et al., 2010; Solis et al., 2015). The AGE equipment combined with EA can be utilized as a fully automated sample preparation system to be employed for 14C measurements using standard-sized carbon samples (~1 mg). In fact, currently the third generation of the AGE equipment (AGE3) is commercially available (Solís et al., 2015). Notably, small-mass 14C measurements have been performed on analyte samples characterized by a carbon mass below ~0.1–0.05 mg by the AMS system after manual graphitization using the small-volume vacuum glass line (e.g., Delqué-Količ et al., 2013). However, the EA-AGE3 system has not yet been utilized to perform small-mass sample graphitization for the IAEA standards. In order to evaluate the suitability of the EA-AGE3 system for use in the small-mass graphitization and highefficiency sample preparation techniques, the EA-AGE3 Preliminary report on small-mass graphitization for radiocarbon dating using EA-AGE3 at JAEA-AMS-TONO","PeriodicalId":12682,"journal":{"name":"Geochemical Journal","volume":"56 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78946947","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}

引用次数: 2

Mineralization in the Shimensi Deposit, Northern Jiangxi Province, China: Evidence from Pb and O isotopes 赣北石门寺矿床成矿作用:来自Pb、O同位素的证据

IF 0.8 4区地球科学

Geochemical Journal Pub Date : 2021-01-01 DOI: 10.2343/geochemj.2.0616

Z. Ye, Peng-liang Wang, Yike Li, Xin-kui Xiang, Hui Zhang

引用次数: 3

Combined tracers in hot spring waters across the Kii Peninsula, Japan: Implications for the origins of metamorphic fluids of the SW Japan forearc 日本纪井半岛温泉中的复合示踪剂:对日本西南弧前变质流体起源的启示

IF 0.8 4区地球科学

Geochemical Journal Pub Date : 2021-01-01 DOI: 10.2343/geochemj.2.0637

Koki Momose, Makoto Shiogama, M. Hori, K. Kandori, Y. Nishio

{"title":"Combined tracers in hot spring waters across the Kii Peninsula, Japan: Implications for the origins of metamorphic fluids of the SW Japan forearc","authors":"Koki Momose, Makoto Shiogama, M. Hori, K. Kandori, Y. Nishio","doi":"10.2343/geochemj.2.0637","DOIUrl":"https://doi.org/10.2343/geochemj.2.0637","url":null,"abstract":"Copyright © 2021 by The Geochemical Society of Japan. slab-derived fluid. However, non-meteoric δD-δ18O signatures in spring waters are not always coupled with volcanic-like He isotopic signatures. According to observations from across the Kii Peninsula, non-meteoric δDδ18O signatures are specifically distributed on the western side of the median tectonic line (MTL), despite the wide distribution of groundwater with high 3He/4He ratios (Umeda et al., 2006; Morikawa et al., 2016). Spatial variations of spring waters may be attributed to compositional variations of the original deep fluid (Iwamori et al., 2020). Moreover, non-meteoric δD-δ18O signatures can also be produced by clay mineral dehydration (Dählman and Lange, 2003). Because the δD-δ18O signatures of dehydrated water from clay minerals overlap the isotopic range of magmatic water, the signature could not be used for distinguishing the origins. In this study, we used Cl-B-Li systematics and a mixing model to distinguish the origins of the water from 16 hot springs distributed across the Kii Peninsula, Japan. Li and B are light elements that are characterized by high mobility and are similar to Cl, but with different degrees of incompatibility, depending on the associated mineral phases and temperatures. Therefore, the proportion of these elements has been used for understanding diagenetic and metamorphic processes (Trompetter et al., 1999; Marschall et al., 2009; Reyes and Trompetter, 2012). Reyes and Trompetter (2012) showed the different Cl-BCombined tracers in hot spring waters across the Kii Peninsula, Japan: Implications for the origins of metamorphic fluids of the SW Japan forearc","PeriodicalId":12682,"journal":{"name":"Geochemical Journal","volume":"79 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80135014","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}

引用次数: 2

Shorter average chain length of n-alkanes from flowers than leaves of modern plants: Implications for the use of n-alkane-derived proxies in soils 花中正构烷烃的平均链长比现代植物的叶子短:对土壤中正构烷烃衍生代用品使用的影响

IF 0.8 4区地球科学

Geochemical Journal Pub Date : 2021-01-01 DOI: 10.2343/geochemj.2.0639

Yuejing Fang, Jing Yang, Shijin Zhao, Jie Wu, Yuying Huang, Huan Yang

引用次数: 0

Zircon U-Pb dating of a tuff layer from the Miocene Onnagawa Formation in Northern Japan 日本北部中新世女川组凝灰岩层的锆石U-Pb定年

IF 0.8 4区地球科学

Geochemical Journal Pub Date : 2021-01-01 DOI: 10.2343/geochemj.2.0622

Jumpei Yoshioka, J. Kuroda, N. Takahata, Y. Sano, K. Matsuzaki, H. Hara, G. Auer, S. Chiyonobu, R. Tada

{"title":"Zircon U-Pb dating of a tuff layer from the Miocene Onnagawa Formation in Northern Japan","authors":"Jumpei Yoshioka, J. Kuroda, N. Takahata, Y. Sano, K. Matsuzaki, H. Hara, G. Auer, S. Chiyonobu, R. Tada","doi":"10.2343/geochemj.2.0622","DOIUrl":"https://doi.org/10.2343/geochemj.2.0622","url":null,"abstract":"alternation rhythms have been interpreted as reflecting orbital-forced climate changes (Tada, 1991), timescales of the sedimentary cycles have not been precisely constrained. Knowledge of the mechanism controlling the sediment cycles of the Onnagawa Formation is critical to understand the evolution of the Japan Sea basin and its associated changes in the environment during the Middle-to-Late Miocene, when the global climate faced a significant cooling phase (e.g., Holbourn et al., 2013). Chronostratigraphy of the Onnagawa Formation has been developed by diatom biostratigraphy of diatomaceous sediment in the Oga Peninsula (Koizumi et al., 2009). However, many outcrops of the Onnagawa Formation have been suffered from silica diagenesis, which dissolved most diatom frustules composed of opalA and reprecipitated as opal-CT (e.g., Koizumi et al., 2009; Tada and Iijima, 1983). Consequently, preservation of diatom frustules became very poor and diatom biostratigraphy could be barely applicable. Although the Onnagawa Formation in the studied area is suffered from silica diagenesis, it is well exposed, and its continuous sequence can be obtained by splicing several sections. Zircon U-Pb dating of a tuff layer from the Miocene Onnagawa Formation in Northern Japan","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":"88173806","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}

引用次数: 1

High-precision Δ′17O measurements of geothermal H2O and MORB on the VSMOW-SLAP scale: evidence for active oxygen exchange between the lithosphere and hydrosphere 在VSMOW-SLAP尺度上对地热水和MORB的高精度Δ’17O测量:岩石圈和水圈之间活氧交换的证据

IF 0.8 4区地球科学

Geochemical Journal Pub Date : 2021-01-01 DOI: 10.2343/geochemj.2.0644

Takashi Sambuichi, U. Tsunogai, Kazushige Kura, F. Nakagawa, T. Ohba

{"title":"High-precision Δ′17O measurements of geothermal H2O and MORB on the VSMOW-SLAP scale: evidence for active oxygen exchange between the lithosphere and hydrosphere","authors":"Takashi Sambuichi, U. Tsunogai, Kazushige Kura, F. Nakagawa, T. Ohba","doi":"10.2343/geochemj.2.0644","DOIUrl":"https://doi.org/10.2343/geochemj.2.0644","url":null,"abstract":"have reported 17O-depletion in terrestrial silicates compared with that in hydrospheric H2O such as seawater and meteoric water (Pack et al., 2016; Sharp et al., 2016). The ∆′17O value of mantle-derived silicates ranges from –70 to –30 × 10−6; however, the mean ∆′17O value of meteoric water is +33 × 10−6 and that of seawater collected at various depths is –5 ± 1 × 10−6 (Luz and Barkan, 2010). This difference in ∆′17O between the lithosphere and hydrosphere has been explained by kinetic fractionation of oxygen isotopes during degassing from the magma ocean on the early primitive earth (Tanaka and Nakamura, 2013) or oxygen isotope exchange between the seawater and lithospheric components such as seafloor basalt and continental crust (Pack and Herwartz, 2014; Sengupta et al., 2020; Sengupta and Pack, 2018). The latter explanation has been proposed on the basis of findings that the equilibrium fractionation exponent θ [=ln17α/ln18α; αA-B = RA/ RB where iR corresponds to the abundance ratio of the heavy isotope (iO where i = 17 or 18) to the light isotope (16O).] between silicates and H2O is a funcHigh-precision ∆′17O measurements of geothermal H2O and MORB on the VSMOW-SLAP scale: evidence for active oxygen exchange between the lithosphere and hydrosphere","PeriodicalId":12682,"journal":{"name":"Geochemical Journal","volume":"20 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90492790","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}

引用次数: 3

Equilibrium sulfur isotope fractionations of several important sulfides 几种重要硫化物的平衡硫同位素分馏

IF 0.8 4区地球科学

Geochemical Journal Pub Date : 2021-01-01 DOI: 10.2343/geochemj.2.0623

Jixi Zhang

{"title":"Equilibrium sulfur isotope fractionations of several important sulfides","authors":"Jixi Zhang","doi":"10.2343/geochemj.2.0623","DOIUrl":"https://doi.org/10.2343/geochemj.2.0623","url":null,"abstract":"Copyright © 2021 by The Geochemical Society of Japan. sulfur isotope analyses have been applied to ore deposits; the pioneers of this subject area are Kulp et al. (1956) and Jensen (1957, 1959), among others. At present, sulfur isotopes are used in the fields of geology (e.g., Shanks et al., 1981), biology (e.g., Rees, 1973; Habicht and Canfield, 1997; Habicht et al., 1998; Bolliger et al., 2001; Brüchert et al., 2001; Detmers et al., 2001) and environmental science (e.g., Harris et al., 2013), etc. Notably, research on the mass-independent fractionation of sulfur is currently the most active topic in the field of sulfur isotope geochemistry (Farquhar et al., 2000, 2001, 2013; Savarino et al., 2003; Subrata et al., 2013). It is well known that equilibrium isotope fractionation can be used to estimate the formation temperature of minerals in geological systems (Urey and Greiff, 1935; Urey, 1947). Isotope geochemistry mainly focuses on the change in the isotope ratio between different species rather than on their absolute abundances. The general rule for isotope fractionation is that heavy isotopes tend to form more stable chemical bonds; for example, M34S is more stable than M32S (M stands for metal cations). When considering kinetic isotope effects, molecules with different isotopes have different reaction rates (O’Neil, 1986). In the case of sulfur, 34S/32S is the key point of interest. In most cases, isotope fractionation is relatively small, and most of the time, the δ notation is used to express isotope fractionation. In this article, only the ratio of 34S/32S is Equilibrium sulfur isotope fractionations of several important sulfides","PeriodicalId":12682,"journal":{"name":"Geochemical Journal","volume":"6 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90598499","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}

引用次数: 6