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Characteristics of Hydrogen and Oxygen Isotopes and Noble Gas Isotopes in the Groundwater of Weishan, Wudalianchi, Northeast China 被引量:1
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作者 WANG Shuai HUANG Xuelian +5 位作者 QI Shihua HAN Yongjie KUANG Jian WANG Siqi WANG He XIAO Zhicai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第5期1729-1741,共13页
According to the hydrochemical characteristics, hydrogen and oxygen isotope characteristics and the ratio of noble gas isotopes of the sandstone aquifer and basalt aquifer, this study calculated the recharge temperatu... According to the hydrochemical characteristics, hydrogen and oxygen isotope characteristics and the ratio of noble gas isotopes of the sandstone aquifer and basalt aquifer, this study calculated the recharge temperature and residence time of groundwater in the Weishan area of Wudalianchi, also calculating the contribution of noble gas components from different sources to the samples. Based on the characteristics of hydrogen and oxygen isotopes and noble gases Xe and Ne, the recharge altitude and recharge temperature of the two aquifers were estimated, and the recharge temperature fitting with the NGT model as verified, the results showing that the main recharge altitude of groundwater in the region was 500–600 m, the recharge temperature being 2–7°C. He_(eq) and He_(ea) of the samples have been simulated using the OD model, the content of radioactive ~4He in the crust being obtained, the groundwater ages under the two conditions(closed condition and open condition) both being simulated. The results show that groundwater from the sandstone layer water is older than groundwater from the basalt layer. Hydrochemical characteristics and noble gas isotope ratios indicate that in the basalt aquifer and sandstone aquifer in the Weishan area, in addition to atmospheric and crustal helium, there is also an input of mantle-derived helium. The fault constitutes the uplift channel for groundwater containings mantle components, which results in the mantle source composition in water samples near the fault being much higher than those form non-fault areas. 展开更多
关键词 GROUNDWATER HYDROCHEMISTRY hydrogen and oxygen isotopes noble gases ~4He age mantle source input
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Hydrogen and Oxygen Isotopes of Fluid Inclusion in Halite,Northern Shaanxi Salt Basin China
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作者 DING Ting LIU Chenlin ZHAO Yanjun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期213-213,共1页
The Ordovician was an important transitional period for global climate and organic evolution,the global was in the flood and glacial,Onganism was extinction(Zhan,2007;Trotter et al.,2008;Axel et al.,2010).Under the in... The Ordovician was an important transitional period for global climate and organic evolution,the global was in the flood and glacial,Onganism was extinction(Zhan,2007;Trotter et al.,2008;Axel et al.,2010).Under the influence 展开更多
关键词 hydrogen and oxygen isotopes of Fluid Inclusion in Halite Northern Shaanxi Salt Basin China
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Differences in major ions as well as hydrogen and oxygen isotopes of sediment pore water and lake water 被引量:3
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作者 Zhuo Zhang Hua-ming Guo Zhen Wang 《Water Science and Engineering》 EI CAS CSCD 2018年第2期147-156,共10页
Isotopic and chemical compositions of pore water(PW) are highly relevant to environmental and forensic study. Five lake water(LW)samples and five sediment samples were collected to investigate the effects of pore size... Isotopic and chemical compositions of pore water(PW) are highly relevant to environmental and forensic study. Five lake water(LW)samples and five sediment samples were collected to investigate the effects of pore sizes of sediments on PW chemistry and stable isotopes and determine mechanisms controlling their variations. Six pore water fractions were extracted from different-sized pores in each sediment sample at six sequential centrifugal speeds for chemical and isotopic analysis. The sediments consisted mainly of quartz, feldspar, and clay minerals. The hydrogen and oxygen isotopic compositions of PW are mainly controlled by the overlying LW, although the lag effect of exchange between overlying LW and PW results in isotopic differences when recharge of LW is quicker than isotopic exchange in PW. Identical isotopic compositions of PW from sediments with different pore sizes indicate that isotopic exchange of water molecules with different pore sizes is a quick process. The ratio of average total dissolved solid(TDS) concentration of PW to TDS concentration of LW shows a strong relationship with adsorption capacity of sediments, demonstrating that remobilization of ions bound to sediments mainly causes a chemical shift from LW to PW.Concentrations of Ca^(2+), Mg^(2+),and Cl^-in PW remain unchanged,while concentrations of Na^+,K^+,and SO_4^(2-) slightly increase with decreasing pore size. Chemical differences of PW from sediments with different pore sizes are governed by ion adsorption properties and surface characteristics of different-si zed particles. 展开更多
关键词 PORE size CENTRIFUGAL extraction hydrogen and oxygen isotopes Major ions REMOBILIZATION
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Ore genesis of Badi copper deposit, northwest Yunnan Province, China: evidence from geology, fluid inclusions, and sulfur, hydrogen and oxygen isotopes
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作者 Hejun Yin Jianguo Huang Tao Ren 《Acta Geochimica》 EI CAS CSCD 2018年第4期559-570,共12页
The Badi copper deposit is located in Shangjiang town, Shangri-La County, Yunnan Province. Tectonically, it belongs to the Sanjiang Block. Vapor-liquid two-phase fluid inclusions, CO2-bearing fluid inclusions, and dau... The Badi copper deposit is located in Shangjiang town, Shangri-La County, Yunnan Province. Tectonically, it belongs to the Sanjiang Block. Vapor-liquid two-phase fluid inclusions, CO2-bearing fluid inclusions, and daugh- ter-beating inclusions were identified in sulfide-rich quartz veins. Microthermometric and Raman spectroscopy studies revealed their types of ore-forming fluids: (1) low-tem- perature, low-salinity fluid; (2) medium-temperature, low salinity CO2-bearing; and (3) high-temperature, Fe-rich, high sulfur fugacity. The δ^18O values of chalcopyrite- bearing quartz ranged from 4.96‰ to 5.86%0, with an average of 5.40%0. The δD values of ore-forming fluid in equilibrium with the sulfide-bearing quartz were from - 87‰ to - 107‰, with an average of - 97.86%0. These isotopic features indicate that the ore-forming fluid is a mixing fluid between magmatic fluid and meteoric water. The δ^34S values of chalcopyrite ranged from 13.3‰ to 15.5‰, with an average of 14.3‰. Sulfur isotope values suggest that the sulfur in the deposit most likely derived from seawater. Various fluid inclusions coexisted in the samples; similar homogenization temperature to different phases suggests that the Badi fluid inclusions might have been captured under a boiling system. Fluid boiling caused by fault activity could be the main reason for the mineral precipitation in the Badi deposit. 展开更多
关键词 Badi copper deposit Fluid inclusion Sulfurisotope hydrogen and oxygen isotope Ore genesis
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Power-law patterns in the Phanerozoic sedimentary records of carbon, oxygen, sulfur,and strontium isotopes
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作者 Haitao Shang 《Journal of Palaeogeography》 SCIE CSCD 2024年第1期116-126,共11页
Power-law patterns appear in a variety of natural systems on the modern Earth;nevertheless,whether such behaviors appeared in the deep-time environment has rarely been studied. Isotopic records in sedimentary rocks, w... Power-law patterns appear in a variety of natural systems on the modern Earth;nevertheless,whether such behaviors appeared in the deep-time environment has rarely been studied. Isotopic records in sedimentary rocks, which are widely used to reconstruct the geological/geochemical conditions in paleoenvironments and the evolutionary trajectories of biogeochemical cycles, offer an opportunity to investigate power laws in ancient geological systems. In this study, I focus on the Phanerozoic sedimentary records of carbon, oxygen, sulfur, and strontium isotopes, which have well documented and extraordinarily comprehensive datasets. I perform statistical analyses on these datasets and show that the variations in the sedimentary records of the four isotopes exhibit power-law behaviors. The exponents of these power laws range between 2.2 and 2.9;this narrow interval indicates that the variations in carbon, oxygen, sulfur, and strontium isotopes likely belong to the same universality class, suggesting that these systematic power-law patterns are governed by universal, scale-free mechanisms. I then derive a general form for these power laws from a minimalistic model based on basic physical principles and geosystem-specific assumptions, which provides an interpretation for the power-law patterns from the perspective of thermodynamics. The fundamental mechanisms regulating such patterns might have been ubiquitous in paleoenvironments, implying that similar power-law behaviors may exist in the sedimentary records of other isotopes. 展开更多
关键词 Power laws Phanerozoic sedimentary records Carbon isotope(δ~(13)C) oxygen isotope(δ~(18)O) Sulfur isotope(δ~(34)S) strontium isotope(~(87)Sr/~(86)Sr)
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Origin of the Yueguang gold deposit in Xinhua, Hunan Province, South China: insights from fl uid inclusion and hydrogen–oxygen stable isotope analysis
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作者 Hongxin Fan Qiang Wang +2 位作者 Yulong Yang Yao Tang Hao Zou 《Acta Geochimica》 EI CAS CSCD 2024年第2期235-254,共20页
The Yueguang gold deposit is located in Fengjia,Xinhua County,Hunan Province,South China.It represents a recently discovered small-scale gold deposit situated in the southwestern region of the Jiangnan Orogenic Belt,w... The Yueguang gold deposit is located in Fengjia,Xinhua County,Hunan Province,South China.It represents a recently discovered small-scale gold deposit situated in the southwestern region of the Jiangnan Orogenic Belt,west of the Baimashan granitic batholith.In order to discern the characteristics of the ore-formingfluids,the underlying mineralization processes,and establish a foundation for the origin of the Yueguang gold depositfluid inclusion micro-thermometry,as well as quartz hydrogen and oxygen isotope analysis,have been carried out on samples obtained from various stages of mineralization.The hydrothermal miner-alization stages within the Yueguang gold deposit can be categorized into three stages:(i)the barren,pre-ore quartz-pyrite stage(Stage Ⅰ),the quartz-pyrite-gold stage(Stage Ⅱ),and the post-ore quartz-carbonate stage(Stage Ⅲ),with the second stage being the main mineralization stage.Thefluid inclusions identified in samples from the main min-eralization stage can predominantly be described with the NaCl–H_(2)O and CO_(2)–NaCl–H_(2)O systems.These inclusions display homogenization temperatures ranging from 158.8 to 334.9℃,and thefluid salinity ranges from 0.3%to 4.0%(wt.%NaCl equiv.).Laser Raman spectroscopy analysis of individual inclusions further reveals the presence of gas-phases such as CO_(2),CH_(4),and N_(2).Isotopic analysis indicatesδ^(18)Ofluid values ranging from 3.95 to 6.7‰ and δDH_(2)O values ranging from-71.9 to-55.7‰.These results indi-cate that the ore-formingfluid of the Yueguang gold deposit belongs to metamorphic hydrothermalfluids of middle-low temperature and low salinity.In the process of ore formation,gold is transported in the form of Au(HS)2-complexes,with gold deposition being driven byfluid immiscibility.Therefore,the Yueguang gold deposit is categorized as an orogenic gold deposit dominated by metamorphic hydrother-malfluid.It may become a new target for gold exploration in the Baimashan region,central Hunan Province. 展开更多
关键词 Hunan province Yueguang gold deposit Fluid inclusions hydrogenoxygen isotopes Laser Raman Fluid immiscibility Orogenic gold deposit
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Origin of the Dashuigou independent tellurium deposit at Qinghai–Xizang Plateau: constraints from the light stable isotopes C, O, and H
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作者 Jianzhao Yin Yuhong Chao +2 位作者 Haoyu Yin Hongyun Shi Shoupu Xiang 《Acta Geochimica》 EI CAS CSCD 2024年第2期385-398,共14页
By studying the light isotopic compositions of carbon,oxygen,and hydrogen,combined with previous research results on the ore-forming source of the deposit,the authors try to uncover its metallogenic origin.The δ^(18)... By studying the light isotopic compositions of carbon,oxygen,and hydrogen,combined with previous research results on the ore-forming source of the deposit,the authors try to uncover its metallogenic origin.The δ^(18)O and δ^(13)C isotope signatures of dolomite samples vary between 10.2 and 13.0‰,and between−7.2 and−5.2‰,respectively,implying that the carbon derives from the upper mantle.δD and δ^(18) O of quartz,biotite,and muscovite from diff erent ore veins of the deposit vary between−82 and−59‰,and between 11.6 and 12.4‰,respectively,implying that the metallogenic solutions are mainly magmatic.According to the relevant research results of many isotope geologists,the fractionation degree of hydrogen isotopes increases as the depth to the Earth’s core increases,and the more diff erentiated the hydrogen isotopes are,the lower their values will be.In other words,mantle-derived solutions can have extremely low hydrogen isotope values.This means that the δD‰ value−134 of the pyrrhotite sample numbered SD-34 in this article may indicate mantle-derived oreforming fl uid of the deposit.The formation of the Dashuigou tellurium deposit occurred between 91.71 and 80.19 Ma. 展开更多
关键词 Carbon oxygen and hydrogen isotopes ORIGIN Independent tellurium deposit The Qinghai–Xizang Plateau
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Oxygen and Hydrogen Isotopes of Waters in the Ordos Basin,China:Implications for Recharge of Groundwater in the North of Cretaceous Groundwater Basin 被引量:10
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作者 YANG Yuncheng SHEN Zhaoli +4 位作者 WENG Dongguang HOU Guangcai ZHAO Zhenhong WANG Dong PANG Zhonghe 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第1期103-113,共11页
Hundreds of precipitation samples collected from meteorological stations in the Ordos Basin from January 1988 to December 2005 were used to set up a local meteoric water line and to calculate weighted average isotopic... Hundreds of precipitation samples collected from meteorological stations in the Ordos Basin from January 1988 to December 2005 were used to set up a local meteoric water line and to calculate weighted average isotopic compositions of modern precipitation. Oxygen and hydrogen isotopes, with averages of-7.8‰ and -53.0‰ for δ^18O and δD, respectively, are depleted in winter and rich in spring, and gradually decrease in summer and fall, illustrating that the seasonal effect is considerable. They also show that the isotopic difference between south portion and north portion of the Ordos Basin are not obvious, and the isotope in the middle portion is normally depleted. The isotope compositions of 32 samples collected from shallow groundwater (less than a depth of 150 m) in desert plateau range from -10.6‰ to -6.0‰ with an average of-8.4‰ for δ^18O and from -85‰ to -46‰ with an average of-63‰ for δD. Most of them are identical with modern precipitation. The isotope compositions of 22 middle and deep groundwaters (greater than a depth of 275 m) fall in ranges from -11.6‰ to -8.8‰ with an average of -10.2‰ for δ^18O and from -89‰ to -63‰ with an average of -76‰ for δD. The average values are significantly less than those of modern precipitation, illustrating that the middle and deep groundwaters were recharged at comparatively lower air temperatures. Primary analysis of ^14C shows that the recharge of the middle and deep groundwaters started at late Pleistocene. The isotopes of 13 lake water samples collected from eight lakes define a local evaporation trend, with a relatively flat slope of 3.77, and show that the lake waters were mainly fed by modern precipitation and shallow groundwater. 展开更多
关键词 GROUNDWATER lake water oxygen and hydrogen isotopes precipitation Ordos Basin
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Estimating distribution of water uptake with depth of winter wheat by hydrogen and oxygen stable isotopes under different irrigation depths 被引量:10
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作者 GUO Fei MA Juan-juan +3 位作者 ZHENG Li-jian SUN Xi-huan GUO Xiang-hong ZHANG Xue-lan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第4期891-906,共16页
Crop root system plays an important role in the water cycle of the soil-plant-atmosphere continuum. In this study, com- bined isotope techniques, root length density and root cell activity analysis were used to invest... Crop root system plays an important role in the water cycle of the soil-plant-atmosphere continuum. In this study, com- bined isotope techniques, root length density and root cell activity analysis were used to investigate the root water uptake mechanisms of winter wheat (Triticum aesfivum L.) under different irrigation depths in the North China Plain. Both direct inference approach and multisource linear mixing model were applied to estimate the distribution of water uptake with depth in six growing stages. Results showed that winter wheat under land surface irrigation treatment (Ts) mainly absorbed water from 10-20 cm soil layers in the wintering and green stages (66.9 and 72.0%, respectively); 0-20 cm (57.0%) in the jointing stage; 0-40 (15.3%) and 80-180 cm (58.1%) in the heading stage; 60-80 (13.2%) and 180-220 cm (35.5%) in the filling stage; and 0-40 (46.8%) and 80-100 cm (31.0%) in the ripening stage. Winter wheat under whole soil layers irrigation treatment (Tw) absorbed more water from deep soil layer than Ts in heading, filling and ripening stages. Moreover, root cell activity and root length density of winter wheat under TW were significantly greater than that of Ts in the three stages. We concluded that distribution of water uptake with depth was affected by the availability of water sources, the root length density and root cell activity. Implementation of the whole soil layers irrigation method can affect root system distribution and thereby increase water use from deeper soil and enhance water use efficiency. 展开更多
关键词 hydrogen and oxygen stable isotopes multisource linear mixing model winter wheat distribution of wateruptake with depth
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Characteristics of hydrogen/oxygen isotopes in water masses and implications for spatial distribution of freshwater in the Amundsen Sea,Southern Ocean
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作者 SHAO Hebin HE Jianfeng +4 位作者 LUO Guangfu LAN Musheng YU Lejiang GUO Guijun LIAN Ergang 《Advances in Polar Science》 CSCD 2021年第3期221-238,共18页
Antarctica’s marginal seas are of great importance to atmosphere-ocean-ice interactions and are sensitive to global climate change.Multiple factors account for the freshwater budget in these regions,including glacier... Antarctica’s marginal seas are of great importance to atmosphere-ocean-ice interactions and are sensitive to global climate change.Multiple factors account for the freshwater budget in these regions,including glacier melting,seasonal formation/decay of sea ice,and precipitation.Hydrogen(H)and oxygen(O)isotopes represent useful proxies for determining the distribution and migration of water masses.We analyzed the H and O isotopic compositions of 190 seawater samples collected from the Amundsen Sea during the 34th Chinese Antarctic Research Expedition in 2017/2018.The upper-oceanic structure(<400 m)and freshwater(meteoric water and sea ice melt)distribution in the Amundsen Sea were identified based on conductivity-temperature-depth data and the H and O isotopic composition.Antarctic Surface Water,characterized as cold and fresh with low H and O isotopic ratios,was found distributed mainly in the upper~150 m between the Antarctic Slope Front and Polar Front,where it had been affected considerably by upwelled Upper Circumpolar Deep Water(UCDW)between 68°S and 71°S.A three-endmember(meteoric water,sea ice melt,and Circumpolar Deep Water)mixing model indicated that waters with relatively high proportions(>3%)of freshwater generally lie in the upper~50 m and extend from Antarctica to~65°S in the meridional direction(anomalously low freshwater proportion occurred between 68°S and 71°S).Winter Water mainly occupied the layer between 50 and 150 m south of 71°S in the western Amundsen Sea.The water structure and spatial distribution of freshwater in the upper Amundsen Sea were found influenced mainly by the rates of basal and surficial melting of ice shelves,seasonal alternation of sea ice melt/formation,wind forcing,and regional bathymetry.Owing to the distance between heavy sea ice boundary(HSIB)and ice shelves is much shorter in the western HSIB than the east HSIB,the western part of the heavy sea ice boundary includes a higher proportion of freshwater than the eastern region.This study,which highlighted the distribution and extent of freshwater derived from ice(ice shelves and sea ice)melt,provides important evidence that the offshore drift pathway of cold and fresh Antarctic continental shelf water is likely interrupted by upwelled UCDW in the Amundsen Sea. 展开更多
关键词 hydrogen and oxygen isotopes FRESHWATER ICE shelf SEA ICE UPWELLING Circumpolar Deep Water Amundsen SEA Southern Ocean
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The hydrogen and oxygen isotopic compositions of hydroxyl in clay mineral from a weathering profile: New proxies for paleo-climate change?
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作者 Chengfan Yang Shouye Yang Ni Su 《Acta Geochimica》 EI CAS CSCD 2017年第3期370-373,共4页
Recent studies suggest that the hydrogen and oxygen isotopic compositions of clay minerals can indicate paleoclimate.Here,we report mineralogy and stable isotopic records(d D and δ^(18)O_(OH))of a weathering profile ... Recent studies suggest that the hydrogen and oxygen isotopic compositions of clay minerals can indicate paleoclimate.Here,we report mineralogy and stable isotopic records(d D and δ^(18)O_(OH))of a weathering profile located in the Fujian Province,aiming to validate whether hydroxyl stable isotopes can indicate paleo-precipitation and paleo-temperature.Our results indicate that the d D and δ^(18)O_(OH)changes in the kaolinite hydroxyl of the weathering profile are basically determined by the isotopic composition of paleo-meteoric water and paleotemperature,respectively.Nevertheless,whether the d D and δ^(18)O_(OH)of kaolinite can quantitatively indicate paleo-precipitation and paleo-temperature needs to be verified further,and especially,the structural oxygen isotopic composition that is the essential element for the kaolinite formation temperature calculation has to be constrained in future work. 展开更多
关键词 Weathering profile hydrogen and oxygen isotopes HYDROXYL KAOLINITE
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Rare-earth and trace elements and hydrogen and oxygen isotopic compositions of Cretaceous kaolinitic sediments from the Lower Benue Trough, Nigeria: provenance and paleoclimatic significance 被引量:2
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作者 Anthony T.Bolarinwa Sunday O.Idakwo David L.Bish 《Acta Geochimica》 EI CAS CSCD 2019年第3期350-363,共14页
This study evaluated the Cretaceous(Campanian–Maastrichtian) kaolinitic sediments of the Ajali/Mamu and Enugu/Nkporo Formations from the Lower Benue Trough of Nigeria. A combined method of inductively coupled plasma... This study evaluated the Cretaceous(Campanian–Maastrichtian) kaolinitic sediments of the Ajali/Mamu and Enugu/Nkporo Formations from the Lower Benue Trough of Nigeria. A combined method of inductively coupled plasma–mass spectrometry and isotope ratio mass spectrometry was used to investigate trace and rareearth element geochemistry and hydrogen and oxygen isotopic compositions. These data were then used to infer the sediments' provenance and paleoclimatic conditions during their deposition. The sediments contained low concentrations of most trace elements, with the exceptions of Zr(651–1352 ppm), Ba(56–157 ppm), V(38–90 ppm),and Sr(15.1–59.6 ppm). Average values of Co and Ni were1.5 and 0.7 ppm, respectively. Trace and rare earth element values were lower than corresponding values for upper continental crust and Post-Archean Australian Shale, with the exception of Zr. The samples showed only slight light rare-earth enrichment and nearly flat heavy rare-earth depletion patterns, with negative Eu and Tm anomalies,typical of felsic sources. Geochemical parameters such as La/Sc, Th/Sc, and Th/Co ratios support that the kaolinitic sediments were derived from a felsic rock source, likely deposited in an oxic environment.^(18 )O values ranged from+ 15.4 to + 21.2% for the investigated samples, consistent with a residual material derived from chemicalweathering of felsic rock and redeposited in a sedimentary basin(typical values of + 19 to + 21.2%). While in the basin, the sediments experienced extended interactions with meteoric water enriched in d D and d16 O. However,the variation in d D and d16 O values for the investigated samples is attributed to the high temperature of formation(54–91 °C). The d D and d^(18 )O values suggest that the sediments, although obtained from different localities within the Lower Benue Trough, formed under similar hot,tropical climatic conditions. 展开更多
关键词 RARE-EARTH and trace elements oxygen/ hydrogen isotopic composition Kaolinitic SEDIMENTS LOWER Benue TROUGH NIGERIA
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Study on Analytical Methods for Hydrogen and Oxygen Isotope in Water Sample
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作者 ZHANG Lin LIU Fuliang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期175-175,共1页
1 Introduction The stable isotopes of hydrogen and oxygen(δ2H andδ18O)are excellent tracers for studies on the natural water cycle.The isotopic signature of different water bodies
关键词 hydrogen isotope oxygen isotope equilibration technique metal chromium
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Oxygen and hydrogen isotope ratios of chert from the Sixtymile Formation in Grand Canyon National Park,USA:a warm palaeoclimate,freshwater deposit
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作者 Ray Kenny 《Acta Geochimica》 EI CAS CSCD 2017年第2期250-259,共10页
New oxygen and hydrogen isotope ratios of chert from middle, intraformational breccias, and upper breccia members of the Sixtymile Formation(SMF) in eastern Grand Canyon National Park(AZ) yield palaeoclimate estim... New oxygen and hydrogen isotope ratios of chert from middle, intraformational breccias, and upper breccia members of the Sixtymile Formation(SMF) in eastern Grand Canyon National Park(AZ) yield palaeoclimate estimates between 27 and 33℃. The isotopic compositions of cherts define a domain approximately parallel to the meteoric water line when plotted on a δD–δ-(18)O diagram; these data indicate that meteoric water was involved during formation of the chert. In thin section, the absence of interlocking mega quartz(〉35 lm) and silicafilled fractures and veins, along with preserved micromorphological silica fabrics, suggest that the chert has not been permeated by later hydrothermal fluids. Petrographic observations in thin section such as cyclic silica precipitation phases and glaebular micromorphologic fabrics lend support to the interpretation that meteoric waters were involved during chert precipitation. The post 742 Ma SMF has been correlated with diamictite(transition) beds of the Kingston Peak Formation(CA), which in turn have been interpreted to have been deposited during the Sturtian Ice Age(-750–700 Ma). Absence of facetted and striated clasts and other diagnostic glaciogenic features in the SMF,an unconformable contact with the stratigraphically older Chuar Group, coupled with warm palaeotemperature data inferred from stable isotope values of chert, tentatively suggest that deposition of sediment in the SMF likely did not take place during the Sturtian Ice Age. 展开更多
关键词 oxygen and hydrogen isotope ratios Chert Sturtian Ice Age Grand Canyon Sixtymile Formation Snowball Earth
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Oxygen and Carbon Isotope Composition in Primary Carbonatites of the World: Data Summary and Linear Trends
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作者 Alexander V. Bolonin 《Open Journal of Geology》 2019年第8期424-439,共16页
The article contains the results of statistical processing of a large summary of δ18О-δ13С isotope values in the primary carbonatites of the world. From literary sources, 1593 paired values δ18О-δ13С from 173 ... The article contains the results of statistical processing of a large summary of δ18О-δ13С isotope values in the primary carbonatites of the world. From literary sources, 1593 paired values δ18О-δ13С from 173 carbonatite occurrences of the world were collected. This report exceeds all previously published reports on С-О isotopes in carbonatites by quantity of the used values and carbonatite occurrences. Statistical data analysis is performed on diagrams in the coordinates δ18О (‰, V-SMOW) - δ13С (‰, V-PDV). For each carbonatite occurrence, not only the arithmetic mean values are calculated, but also the regression line. Distinct linear trend of δ18О-δ13С values is found in half of the carbonatite occurrences. The starting, middle, and ending points of the trend line are determined. The slope of the trend line (angular coefficient) varies over a wide range. The trend is dominated by an average angular coefficient of 0.30 (positive correlation δ18О-δ13С). In the literature, it is associated with the Rayleigh high-temperature fractionation of carbonatite melts or with their sedimentary contamination. Half of the carbonatite occurrences do not show a linear trend of δ18О-δ13С values, probably due to the combined action of multidirectional trends. The initial ratio 87Sr/86Sr in the used carbonatite occurrences varies from 0.701 to 0.708. Statistics show no correlation of 87Sr/86Sr with the δ18О-δ13С system. 展开更多
关键词 CARBONATITE Occurrences oxygen Carbon and strontium isotopes Linear TRENDS
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Genesis of the Ciemas Gold Deposit and Relationship with Epithermal Deposits in West Java,Indonesia:Constraints from Fluid Inclusions and Stable Isotopes 被引量:2
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作者 ZHENG Chaofei ZHANG Zhengwei +1 位作者 WU Chengquan YAO Junhua 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第3期1025-1040,共16页
The Ciemas gold deposit is located in West Java of Indonesia, which is a Cenozoic magmatism belt resulting from the Indo-Australian plate subducting under the Eurasian plate. Two different volcanic rock belts and asso... The Ciemas gold deposit is located in West Java of Indonesia, which is a Cenozoic magmatism belt resulting from the Indo-Australian plate subducting under the Eurasian plate. Two different volcanic rock belts and associated epithermal deposits are distributed in West Java: the younger late Miocene-Pliocene magmatic belt generated the Pliocene-Pleistocene epithermal deposits, while the older late Eocene-early Miocene magmatic belt generated the Miocene epithermal deposits. To constrain the physico-chemical conditions and the origin of the ore fluid in Ciemas, a detailed study of ore petrography, fluid inclusions, laser Raman spectroscopy, oxygen-hydrogen isotopes for quartz was conducted. The results show that hydrothermal pyrite and quartz are widespread, hydrothermal alteration is well developed, and that leaching structures such as vuggy rocks and extension structures such as comb quartz are common. Fluid inclusions in quartz are mainly liquid-rich two phase inclusions, with fluid compositions in the NaCI-H2O fluid system, and contain no or little CO2. Their homogenization temperatures cluster around 240℃-320℃, the salinities lie in the range of 14-17 wt.% NaCI equiv, and the calculated fluid densities are 0.65-1.00 g/cm^3. The values of δ18OH2O-VSMOW for quartz range from +5.5%0 to +7.7‰, the δDVSMOW of fluid inclusions in quartz ranges from -70‰ to -115‰. All of these data indicate that mixing of magmatic fluid with meteoric water resulted in the formation of the Ciemas deposit. A comparison among gold deposits of West Java suggests that Miocene epithermal ore deposits in the southernmost part of West Java were more affected by magmatic fluids and exhibit a higher degree of sulfidation than those of Pliocene-Pleistocene. 展开更多
关键词 fluid inclusions oxygen and hydrogen isotopes EPITHERMAL SUBDUCTION Ciemas golddeposit West Java Indonesia
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Variation of soil-plant-atmosphere continuum stable isotope and water source in Qinghai spruce forest of the eastern Qilian Mountains 被引量:2
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作者 ZHOU Jun-ju WANG Xue +9 位作者 MA Luo LUO Chu-yu TANG Hai-tao GUO Zhao-nan CHEN Jia-wei SHI Su-han SHI Wei WEI Wei ZHANG Dong-xia LIU Chun-fang 《Journal of Mountain Science》 SCIE CSCD 2023年第2期355-366,共12页
Understanding the hydrogen and oxygen stable isotope composition and characteristics of different water bodies in soil-plant-atmosphere continuum is of significance for revealing regional hydrological processes and wa... Understanding the hydrogen and oxygen stable isotope composition and characteristics of different water bodies in soil-plant-atmosphere continuum is of significance for revealing regional hydrological processes and water cycle mechanisms.In this study,we analyzed the stable isotopic composition,relationship and indicative significance of precipitation,soil water(0~100 cm depth)and xylem water of Qinghai spruce(Picea crassifolia)forest in the eastern Qilian Mountains,and explored the circulation process among different water bodies.The results show that the stable isotopes of precipitation vary greatly during the entire observation period.The values ofδ2H andδ^(18)O in the precipitation in the warm season are richer than those in the cold season,and the slope and intercept of local meteoric water line(LMWL,δ2H=6.79δ18O+7.13)are both smaller than global meteoric water line(GMWL,δ2H=8.17δ18O+10.56).The stable isotopes of soil water at different depths underwent different degrees of evaporative fractionation,and theδ18O andδ2H of shallow soil water varied greatly,while the deep soil water tended to be similar.The topsoil(0~10 cm)can respond quickly to precipitation,and the response of the deep soil has a time lag.In the whole growing season,0~30 cm and 60~100 cm soil water are the main water sources of Qinghai spruce.The water source of Qinghai spruce was from all soil layers in May and September,mainly from the shallow soil layer(0~30 cm)in August and October,and mainly from the deep soil layer(60~100 cm)in June and July. 展开更多
关键词 Stable hydrogen isotope Stable oxygen isotope Soil-plant-atmosphere continuum SPAC Plant water use IsoSource model
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Stable isotopes of water as a tracer for revealing spatial and temporal characteristics of groundwater recharge surrounding Qinghai Lake,China
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作者 LI Dong-sheng CUI Bu-li +1 位作者 ZHAO Yun-duo ZUO Feng-lin 《Journal of Mountain Science》 SCIE CSCD 2022年第9期2611-2621,共11页
Studying spatial and temporal characteristics of regional groundwater recharge will guide the scientific management and sustainable development of regional water resources.This study investigated stable isotopes(δ^(1... Studying spatial and temporal characteristics of regional groundwater recharge will guide the scientific management and sustainable development of regional water resources.This study investigated stable isotopes(δ^(18)O and δ^(2) H)of precipitation,groundwater,river water and lake water during 2019-2020 in Qinghai Lake Basin to reveal the spatial and temporal characteristics of groundwater recharge.The local meteoric water line was simulated using ordinary least squares regression(δ^(2) H=7.80δ^(18)O+10.60).The local evaporation lines of the river water,lake water and groundwater were simulated asδ^(2) H=6.21δ^(18)O-0.72,δ^(2) H=5.73δ0-3.60 and δ^(2) H=6.59δ0+1.76,respectively.The δ^(2) H and δ^(18)O of river water and groundwater were in more depleted values due to the recharge by precipitation at high altitudes or precipitation effects,and theδ^(2) H andδ^(18)O of the lake water were in more enriched values because of evaporation.The relationship between the δ^(2) H and δ^(18)O of groundwater and river water was not significantly different,indicating a strong hydrological connection between the groundwater and river water surrounding Qinghai Lake.Additionally,the maximum values of δ^(18)O and the minimum values of lc-excess of groundwater in most regions were both in August,and the minimum values of δ^(18)O and the maximum values of lc-excess of groundwater in most regions were both in October.Therefore,the groundwater was recharged by soil water with strong evaporation in August and recharged by precipitation at high altitudes in October.The recharge rate of groundwater was relatively fast in areas with large slopes and large hydraulic gradients(e.g.,south of Qinghai Lake),and in areas with strong hydrological connections between the groundwater and river water(e.g.,the Buha River Valley).Those results can provide data support for protection and utilization of water resources in Qinghai Lake Basin,and provide reference for groundwater research in closed lake basins on the Qinghai-Tibet Plateau. 展开更多
关键词 Recharge of groundwater hydrogen and oxygen stable isotopes Line-conditioned excess Surface water and groundwater Qinghai Lake Basin
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基于氢氧同位素的平原湖荡地表水与地下水转化研究
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作者 卢小慧 王梦瑶 +3 位作者 龚绪龙 武鑫 张海涛 卫岩曈 《水利学报》 EI CSCD 北大核心 2024年第4期416-427,共12页
地表水与地下水间的相互转化以及量化地下水补给量是湖泊水循环研究的重要内容。本文采集了元荡湖区域湖水、地下水样品,测试了其氢氧稳定同位素组成和水化学组成,运用Piper三线图分析其水化学类型、通过钻孔实测的地下水埋深绘制元荡... 地表水与地下水间的相互转化以及量化地下水补给量是湖泊水循环研究的重要内容。本文采集了元荡湖区域湖水、地下水样品,测试了其氢氧稳定同位素组成和水化学组成,运用Piper三线图分析其水化学类型、通过钻孔实测的地下水埋深绘制元荡湖区域旱季(2022年12月)和雨季(2023年6月)的地下水水位等值线图,结合电导率(EC)和溶解性总固体(TDS)定性分析地表水-地下水之间的转化关系,利用同位素水量平衡方程、线性端元混合模型定量评价了湖水、地下水、河水和降水之间的转化量。结果表明,研究区湖水和地下水的水化学类型均为HCO_(3)^(-)·SO_(4)^(2-)·Ca^(2+)·Na^(+)·Mg^(2+),旱季和雨季湖水均受到地下水的补给,拟合得到的湖水旱季、雨季氢氧稳定同位素线性回归方程表明雨季斜率较小,蒸发更为强烈。湖水主要由河水、地下水和降水补给,其三者在旱季的补给比例分别为59%、26%和15%,在雨季的补给比例分别为23%、39%和38%。本文成果为元荡湖区域以及太湖流域的综合治理提供了科学依据。 展开更多
关键词 平原湖荡 元荡湖 氢氧稳定同位素 水化学特征 同位素水量平衡模型 线性端元混合模型
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张渤断裂带山东东部地热水地球化学特征分析
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作者 陈其峰 李营 +5 位作者 张帆 孙宇飞 贾震 杜桂林 曹一 冯恩国 《地震》 CSCD 北大核心 2024年第3期21-37,共17页
通过对张渤断裂带山东东部地区温泉/地热井采样,测试水样主量元素和氢氧同位素,进行水文地球化学特征分析,结果表明:(1)地热水化学类型主要有Ca-HCO_(3)、Na-Cl、Na-HCO_(3)、Na-SO_(4)。(2)δD、δ^(18)O的测值范围分别为-39.90‰~-68... 通过对张渤断裂带山东东部地区温泉/地热井采样,测试水样主量元素和氢氧同位素,进行水文地球化学特征分析,结果表明:(1)地热水化学类型主要有Ca-HCO_(3)、Na-Cl、Na-HCO_(3)、Na-SO_(4)。(2)δD、δ^(18)O的测值范围分别为-39.90‰~-68.00‰和-5.00‰~-8.50‰,均落在中国大气降水线和中国东部地区大气降水线下方附近,说明地热水来源为大气降水。计算得到研究区地热水最小循环深度为1183 m,最大循环深度为4271 m,补给高程大致变化范围为430.0~1366.6 m。(3)γNa/γCl变化范围在0.509~38.37,其中临朐揽翠湖、磁山温泉变质系数相对较高,表明受矿物溶滤作用较大。(4)Na-K-Mg三角图表明地热水样大多为部分平衡水,仅有高青县御泉汤温泉为平衡水。 展开更多
关键词 张渤断裂带 山东东部 地热水 地球化学特征 氢氧同位素
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