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1.
热水溶液地球化学   总被引:8,自引:0,他引:8  
曾贻善 《地学前缘》1996,3(3):89-95
概述了热水溶液地球化学的主要研究内容和近年来在实验和理论研究方面的进展,包括高温高压下水的热力学性质、状态方程式、介电常数、电导率和电离平衡;NaCl-CO2-H2O体系及其边界体系(NaCl-H2O和CO2-H2O)的相关系、热力学性质和状态方程式,特别是利用人工流体包裹体技术和分子动力学模拟取得的新成果;高温高压电解质稀水溶液的电导测定;以HKF模型为基础,热水溶液中不同物种的标准偏摩尔热力学性质和高温高压有关物理化学参数的估算;热水溶液中的物种形成(热液流体中的矿物溶解度测定、电势测量和谱学研究);水和热水溶液结构的红外和拉曼谱学研究;水和热水溶液的传输性质(粘度和导热系数)。  相似文献   

2.
河南信阳蒙脱石柱化研究Ⅱ.柱结构的稳定性吴平霄张惠芬肖文丁吴金平(中国科学院广州地球化学研究所,广州510640)(中国地质大学,武汉430074)关键词柱结构稳定性蒙脱石柱化用NaOH水解AlCl3水溶液得到的柱化剂撑柱蒙脱石,当NaOH浓度为1....  相似文献   

3.
哀牢山金矿带主要金矿床成矿流体特征   总被引:24,自引:9,他引:24  
毕献武  胡瑞忠 《矿物学报》1997,17(4):435-441
本文系统研究了哀牢山金矿带主要金矿床主成矿阶段石英流体包裹体的化学组成和物理化学性质。结果表明,金成矿流体中的阳离子主要为Na^+、K^+,阴离子主要为Cl^-,SO4^2-,F^-,气相组分中CO2含量普遍偏高,成矿流体属于中低温,中性-弱碱性,具相对还原性,中等含盐度的Na质溶液,其中的金主要以硫氢配合物形式迁移。  相似文献   

4.
吉林海沟金矿床成矿流体的地球化学特征   总被引:15,自引:1,他引:15  
李荫清 《地质学报》1994,68(1):48-61
海沟金矿床石英中含丰富的三相CO2-NaCl-H2O和两相富CO2包裹体,并与两相的NaCl-H2O包裹体共生。成矿流体富含CO2,并有2种类型和来源:高盐度富CO2的NaCl-H2O溶液,来源于浆热液;低盐度NaCl-H2O溶液,来自古大气降水。成矿最佳温度为220-300℃,流体静压力为4-20MPa,矿化深度为1-3km,流体盐度为2-7ω(NaCl)/10^-2,总密度为0.644g/cm  相似文献   

5.
蒸发岩成因的物理化学研究   总被引:3,自引:0,他引:3  
海水体系相平衡的研究是蒸发岩矿床成因研究的物理化学基础。本文简要回顾了我国在这方面的研究成果,包括对黄海海水、南海海水的等温蒸发实验,对潜江凹陷蒸发岩形成机理的研究,对蒸发岩变质作用的研究,对杂卤石形成条件的研究以及K、Na、Mg/Cl-H_2O四元体系多温计算系统的研制等等。这些工作都是以物理化学理论和实验为基础,探讨蒸发岩矿床的形成及演化机理。文中还介绍了近年来由著名物理化学家K.S.Pitzer提出的多组分电解质溶液理论,并简要介绍了Pitzer理论在海水体系相平衡研究中的应用。  相似文献   

6.
蛇纹石化碱性橄榄石玄武岩、水和氢氧化钠溶液的高温高压实验研究宋茂双(中国科学院地球化学研究所,贵阳550002)关键词高温高压碱性玄武岩P波速度熔融-结晶蛇纹石脱水温度作者测量了高温高压下蛇纹石化碱性橄榄玄武岩的P波速度、蛇纹石脱水温度和H2O及Na...  相似文献   

7.
高温高压实验研究是国际地球科学研究的前沿领域和重要方向之一,模拟地球深部的温度和压力环境,研究地球内部物质的物理和化学性质,是解释地震波数据、了解地球内部结构和动力学过程的重要途径.硬柱石是大洋冷俯冲带中的一种重要变质矿物,国内外学者开展了大量的硬柱石高温高压物理化学性质的实验研究,并取得一系列重要成果.本文对硬柱石的高温高压实验研究成果进行了梳理和总结,包括硬柱石的热稳定性、压缩性、振动光谱性质以及物性参数等,指出前人研究中存在的不足,提出未来研究中需要加强的方向.本文旨在让更多的学者对硬柱石的高温高压物理化学性质具有更加全面的认识.  相似文献   

8.
高温高压实验研究是国际地球科学研究的前沿领域和重要方向之一,模拟地球深部的温度和压力环境,研究地球内部物质的物理和化学性质,是解释地震波数据、了解地球内部结构和动力学过程的重要途径。硬柱石是大洋冷俯冲带中的一种重要变质矿物,国内外学者开展了大量的硬柱石高温高压物理化学性质的实验研究,并取得一系列重要成果。本文对硬柱石的高温高压实验研究成果进行了梳理和总结,包括硬柱石的热稳定性、压缩性、振动光谱性质以及物性参数等,指出前人研究中存在的不足,提出未来研究中需要加强的方向。本文旨在让更多的学者对硬柱石的高温高压物理化学性质具有更加全面的认识。  相似文献   

9.
卢焕章  王中刚 《矿物学报》1996,16(1):1-7,T002
本文对新疆阿尔泰可可托海的三号伟晶岩形成的物理化学条件、特别是流体-熔融包裹体进行研究,证明岩浆的确可以分出热液,对于三号伟晶岩脉来说,这种热液组分主要是NaCl-CO2-H2O流体。  相似文献   

10.
高温高压实验作为地球科学研究的重要方向之一,通过模拟地球深部的温度和压力条件,了解地球深部物质的物理化学性质、地球内部结构和动力学演化。角闪石属于双链硅酸盐矿物,为地幔岩石圈的重要组成,广泛分布在海洋地壳、俯冲板块、变质岩和火成岩中。作为俯冲带的重要含水矿物,角闪石的广泛分布和高温高压下的脱水对于理解俯冲带水含量以及水迁移具有重要作用,同时在俯冲带的地震活动、高电导率异常、地震波速异常和岩浆活动中扮演重要角色。在过去的近百年时间里,国内外学者对角闪石高温高压物理化学性质进行了大量的研究。角闪石具有非常复杂的元素组成和结构特征,由此也导致了不同角闪石物理化学性质存在显著不同,包括脱水与脱羟基反应中元素迁移的差异、角闪石形成与分解过程中碱性元素(K+Na)和H2O含量对热稳定的影响、不同空间群结构下的高压结构相变、原位条件下不同结晶方向的电导率异常、不同结晶学优选方位(CPO)下的波速异常等。已有的研究对于角闪石的物理化学性质以及其在俯冲带中发挥的作用有了比较清楚的认识,但仍然有许多问题需要进一步研究,如角闪石的高压脱水动力学、热物性和变形机制等。  相似文献   

11.
The electrical conductance of 0.025 mol NaCl solution was measured at 0.25–3.75 GPa and 20–370°C As shown by the results, the conductance increases with temperature, and there is a liner relation between the reciprocal of temperature and the logarithm of the conductance but their slopes are different at different pressures. The relations between the conductance and pressure is rather complex and there are some discontinuities: in the range of 2.25–3.75 GPa, the conductance increases with the pressure; in the range of 1.25–2.0 GPa, the conductance is not related to the pressure; and at a pressure of 0.75 GPa, the conductance is higher than that at the pressures nearby. This reflects that the NaCl solution has rather different properties of electronic chemistry at various pressures, and probably is an important cause for the existence of the layers with high electrical conductance and low velocity in the Earth's crust and mantle.  相似文献   

12.
Water is the most active component in all geological systems.It has an important effect on the physical properties of minerals and melts.It also plays a key role in the evolution of the Earth.Accurate thermodynamics data on water are currently confined to pressures below 1.0GPa and temperatures below 900℃.Presented in this paper are new data available on the P-T properties of water at pressures up to 5.0GPa,develoged from differential thermal analysis and ultrasonic wave amplitude analysis.It has been found that there may exist another ternary point at 3.0GPa and that ultrasonic wave amplitude change of ice-water transition shows two inflection points above 2.0GPa, consistent with the two peaks of differential thermal curves above 2.0GPa .It may be a new phenomenon which needs further study.  相似文献   

13.
在压力为1.0~4.0 GPa、温度为873~1 223 K下采用Sarltron-1260阻抗/增益-相位阻抗谱分析仪测定了叶蜡石的电导率.实验结果表明,电导率与温度间的关系符合Arrenhius关系式;叶蜡石的脱水引起电导率的突然变化,使电导率急剧上升;脱水前,电导率随着压力增大而减小,其导电机制为电子导电;脱水后,电导率随着压力增大而增大,其导电机制为离子导电.  相似文献   

14.
1 Introduction recognized and accepted by more and more experts engaged in experimental research at high temperature and In-situ laboratory measurement of the electricity of high pressure. This method has been regardedgeological materials at high temperature and high pressure internationally as the most advanced one for the in-situis an important approach to revealing the composition, laboratory measurement of the electric properties ofstructure and properties of materials in the deep interior…  相似文献   

15.
Electrical conductivity of talc was measured at 0.5 GPa and ~473 to ~1,300 K by using impedance spectroscopy both before and after dehydration. Before dehydration, the electrical conductivity of talc increased with temperature and is ~10?4 S/m at 1,078 K. After dehydration, most of the talc changed to a mixture of enstatite and quartz and the total water content is reduced by a factor 6 or more. Despite this large reduction in the total water content, the electrical conductivity increased. The activation enthalpy of electrical conductivity (~125 kJ/mol) is too large for the conduction by free water but is consistent with conduction by small polaron. Our results show that a majority of hydrogen atoms in talc do not enhance electrical conductivity, implying the low mobility of the hydrogen atoms in talc. The observed small increase in conductivity after dehydration may be attributed to the increase in oxygen fugacity that enhances conductivity due to small polaron.  相似文献   

16.
介绍近年来使用静态超高压大腔体实验技术 ,在模拟地球内部的高温高压条件下 ,对地球物质进行的若干物理和化学性质的实验研究。高压同时高温条件下多种岩石样品的弹性波速就位测量揭示出物质的声软化现象和振幅效应 ;高温高压下陨石和岩石的熔融结晶实验发现了陨石硅酸盐相的不混溶现象以及玄武岩熔体结构的变化 ,在玄武岩转变为榴辉岩的实验中观测到了刚玉相 ;在高温高压水的实验中 ,发现了冰 Ⅶ 的亚稳相和熔融前效应以及超临界水及其稀溶液的一些新性质。这些实验结果为探索地球深部物质的性质和状态以及迁移和演化提供了新的依据。  相似文献   

17.
Electrical conductivity measurements on dry polycrystalline K-feldspar were performed at 1.0 to 3.0 GPa and 873 to 1,173 K with a multi-anvil high-pressure apparatus and the Solartron-1260 Impedance/Gain Phase Analyzer in the frequency range of 10?1 to 106 Hz. At each temperature the complex impedance displays a perfect semi-circular arc that represents the grain-interior conduction. Under the experimental conditions, electrical conductivity exponentially increases with increasing temperature and slightly decreases with increasing pressure; however, the effect of pressure on the conductivity is less pronounced than that of temperature. The activation enthalpy decreases slightly from 0.99 to 1.02 eV with increasing pressure, and the activation energy and activation volume for K-feldspar are 0.98 eV and 1.46?±?0.17 cm3/mol, respectively. According to these Arrhenius parameters, ionic conduction is proposed to be the dominant conduction mechanism in K-feldspar at high temperatures and pressures, and potassium ions are the charge carriers transporting by an interstitial mechanism. The diffusion coefficient of potassium at high temperatures was calculated from our conductivity data on K-feldspar using Nernst–Einstein equation, and the results were compared with the previous experimental results.  相似文献   

18.
In order to investigate the origin of the high conductivity anomalies geophysically observed in the mid-lower crust of Tibet Plateau, the electrical conductivity of plagioclase–NaCl–water system was measured at 1.2 GPa and 400–900 K. The relationship between electrical conductivity and temperature follows the Arrhenius law. The bulk conductivity increases with the fluid fraction and salinity, but is almost independent of temperature (activation enthalpy less than 0.1 eV). The conductivity of plagioclase–NaCl–water system is much lower than that of albite–NaCl–water system with similar fluid fraction and salinity, indicating a strong effect of the major mineral phase on the bulk conductivity of the brine-bearing system. The high conductivity anomalies of 10?1 and 100 S/m observed in the mid-lower crust of Tibet Plateau can be explained by the aqueous fluid with a volume fraction of 1 and 9%, respectively, if the fluid salinity is 25%. The anomaly value of 10?1 S/m can be explained by the aqueous fluid with a volume fraction of 6% if the salinity is 10%. In case of Southern Tibet where the heat flow is high, the model of a thin layer of brine-bearing aqueous fluid with a high salinity overlying a thick layer of partial melt is most likely to prevail.  相似文献   

19.
The electrical conductivity of (Mg0.93Fe0.07)SiO3 ilmenite was measured at temperatures of 500–1,200 K and pressures of 25–35 GPa in a Kawai-type multi-anvil apparatus equipped with sintered diamond anvils. In order to verify the reliability of this study, the electrical conductivity of (Mg0.93Fe0.07)SiO3 perovskite was also measured at temperatures of 500–1,400 K and pressures of 30–35 GPa. The pressure calibration was carried out using in situ X-ray diffraction of MgO as pressure marker. The oxidation conditions of the samples were controlled by the Fe disk. The activation energy at zero pressure and activation volume for ilmenite are 0.82(6) eV and −1.5(2) cm3/mol, respectively. Those for perovskite were 0.5(1) eV and −0.4(4) cm3/mol, respectively, which are in agreement with the experimental results reported previously. It is concluded that ilmenite conductivity has a large pressure dependence in the investigated P–T range.  相似文献   

20.
Dehydration temperatures of serpentine were measured in the pressure range between 1.0GPa and 5.0GPa by using the electrical conductivity metod simultaneously at high temperatures and high pressures.The results show that with increasing pressure th dehydration temperature of antigorite increases slightly below 2.0GPa ,but drops markedly above2.0GPa .This strongly suggests that high pressure would favor the dehydration of serpentine minerals and the water released thereby would be an important source of fluids involved in magmatism in a subduction zone and mantle metasomatism,Meanwhile,the greatly enhanced electric conductivity in the presence of water may be one of the reasons underlying the occurrence of a high-conductivity zone in the lower crust.  相似文献   

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