凤凰县茶田汞矿床汞闪锌矿矿物学特征

汞闪锌矿在湖南系首次发现,它是闪锌矿中富汞的变种,含汞达19.48％。主要粉晶数据:3. 15(10),1.922(9),1.64(7),1.25(5),1.11(5)。此外,本文还从物理性质,光学性质,反射光谱,颜色指数,化学成份,红外光谱特征等对该矿物进行了较详细的研究。据目前所掌握的资料,是我国所发现的汞闪锌矿中含汞最高者。     

含铁闪锌矿热容的实验测定与分析

利用美国ＤｕＰｏｎｔ公司的９９００型差示扫描量热仪对３个含铁闪锌矿样品的热容进行了实验测定,并讨论了定压摩尔热容实验值与实验温度的关系。实验结果表明,在实验条件下,含铁闪锌矿的定压摩尔热容与纯闪锌矿的定压摩尔热容存在显著差异,Ｆｅ置换Ｚｎ是造成这种差异的主要原因。     

湖北凤梨山铅锌矿床的闪锌矿标型特征及其成因探讨

凤梨山铅锌矿产于中酸性岩浆岩与三叠系海相碳酸盐地层的热接触变质晕内。闪锌矿为主要的矿石矿物。其成矿作用可分为沉积成岩同生成矿期（I）、渗流热水成矿溶液改造富集成矿期（Ⅱ）和热接触变质成矿期（Ⅲ）。本文根据闪锌矿的地质产状、矿物共生组合及成矿作用的特点，对它进行了物理化和化学性质、矿物包裹体特征、硫与铅同位素地球化学的研究，并探讨了它的成因问题。     

含铁闪锌矿热容与其FeS含量的关系

本文在利用ＤｕＰｏｎｔ公司的９９００型差式扫描量热仪（９９００ＤｉｆｅｒｅｎｔｉａｌＳｃａｎｎｉｎｇＣａｌｏｒｉｍｅｔｅｒ,简称ＤＳＣ）对７个含铁闪锌矿样品的定压摩尔热容量进行实验测定的基础上,分析了热容与ＦｅＳ含量的关系。１样品特点及实验结果７个含...     

低温平衡ZnS-PbS-FeS-H_2S四组分体系的热力学分析

本文介绍了热力学相图在浅成低温热液硫化物矿床中的应用,并以三江地区金顶铅锌矿床中的矿物含量为例进行定量分析。一方面在相同温度下,浓度与矿物(组合)之间存在对应关系,并且一些矿物(组合)对应特定的酸碱条件,例如在400K和105Pa条件下,黄铁矿与方铅矿的组合在碱性环境下稳定,而方铅矿与闪锌矿的组合在酸性环境中稳定,且酸性条件下当lg[Pb2+]≥-11.29时,才开始出现方铅矿;另一方面对比了298.15K和400K条件下矿物共生组合的及介质pH值的变化情况,并得到400K条件下形成矿物或矿物组合所需离子的浓度更高。     

闪锌矿中杂质Fe存在形式的重新认识

闪锌矿作为一种重要的金属硫化物已得到广泛的研究，但在对闪上矿中杂质Ｆｅ存在形式的认识上却存在许多问题。本文对不同含Ｆｅ量的天然闪锌矿测定并分析了Ｆｅ的Ｋ边ＥＸＡＦＳ谱，同时对低温光吸收谱及穆斯堡尔进行了研究。结果表明，Ｆｅ在闪锌矿中主要以六配位形式存在。     

广西建旺铅锌矿床硫化物微量元素组成特征

广西北山矿田内分布有众多铅锌矿床(点),对这些矿床(点)的地质地球化学研究较为薄弱，其铅锌成矿作用与成矿潜力研究缺少实际依据。建旺铅锌矿床是矿田内重要的矿床之一，为了揭示该矿床闪锌矿和黄铁矿微量元素替换机制、成矿流体特征和矿床成因，探讨区内铅锌成矿作用，本文利用激光剥蚀电感耦合等离子质谱仪(LA-ICP-MS)对建旺铅锌矿床的闪锌矿和黄铁矿进行了原位微量元素分析测试。结果显示，闪锌矿中的Mn、Fe、Cd、Ga、Ge和黄铁矿中的Mn、Co、Ni、As主要通过直接替换或耦合替换机制进入矿物晶格中；闪锌矿中的Ag、Pb和黄铁矿中的Cu、Pb既可以通过固溶体形式，也可以以微米级包裹体形式存在于矿物晶体中；建旺铅锌矿床矿化温度为89～191℃(平均124℃)。此外，建旺矿床闪锌矿中的Mn、Ga、Ge和In组成特征与MVT型矿床较为相似，根据二元模式图和黄铁矿Co/Ni值等特征，结合矿床地质特征和成矿流体性质，本文认为建旺铅锌矿床属于MVT型铅锌矿床。     

四川大梁子铅锌矿床闪锌矿中镉富集规律及其意义

扬子地块西南缘铅锌矿床富集区是我国重要的铅锌矿产资源基地。四川会东大梁子铅锌矿床为区内的典型矿床,矿床具多阶段成因特征,矿物的穿插关系清晰,能准确地识别出矿物的形成顺序。闪锌矿为主要矿石矿物。依据矿物形成顺序,划分出三种具有显著不同标型特征的闪锌矿:黑色闪锌矿     

“异常闪锌矿”中一种铜铁硫新出溶相矿物的研究

在内蒙古大井锡石硫化物型铜银锡矿床的闪锌矿中发现了一种铜铁硫新出溶相矿物。作者研究了其光性、化学成分、晶体结构及出溶特征,提出了它作为闪锌矿中一种新的出溶相矿物的重要证据,并对其形成机理结合加热实验及已有的硫化物体系相平衡资料以及矿床地质特点进行了分析。     

江西银山铅锌矿床闪锌矿与石英流体包裹体的对比研究

赣东北地区是我国重要的铜铅锌金银多金属矿集区,银山铅锌(银)铜(金)多金属矿床是赣东北地区一个重要的大型次火山热液型多金属矿床。银山铅锌矿发育有闪锌矿-方铅矿-石英脉,前人研究认为金属矿物与脉石矿物为伴生关系,但是没有强调它们的成因上的联系。本次研究开展了矿石矿物中闪锌矿和伴生脉石矿物中石英的流体包裹体对比研究。通过详细的岩相学观察、显微测温、显微激光拉曼探针工作,对伴生石英脉和闪锌矿内原生包裹体,伴生石英脉中的晚期微细石英脉和闪锌矿内部次生包裹体进行流体特征的对比研究。研究结果显示,伴生石英脉原生流体包裹体比闪锌矿的原生包裹体的平均均一温度高约30℃,明显富集CH₄、N₂、CH₄、CO₂等挥发份,伴生石英脉中的晚期微细石英脉流体包裹体比闪锌矿次生包裹体的平均均一温度高23℃。闪锌矿原生包裹体与想伴生的早期石英脉在平均均一温度有所差别,气相成分差异明显,均表明矿石矿物与伴生脉石矿物可能形成于不同的地质环境,具有不同的温度和流体成分。     

A new method to calculate end-member thermodynamic properties of minerals from their constituent polyhedra II: heat capacity, compressibility and thermal expansion

Thermodynamic calculations in petrology are generally performed at pressures and temperatures beyond the standard state conditions. Accurate prediction of mineral equilibria therefore requires knowledge of the heat capacity, thermal expansion and compressibility for the minerals involved. Unfortunately, such data are not always available. In this contribution we present a data set to estimate the heat capacity, thermal expansion and compressibility of mineral end‐members from their constituent polyhedra, based on the premise that the thermodynamic properties of minerals can be described by a linear combination of the fractional properties of their constituents. As such, only the crystallography of the phase of interest needs to be known. This approach is especially powerful for hypothetical mineral end‐members and for minerals, for which the experimental determination of their thermodynamic properties is difficult. The data set consists of the properties for 35 polyhedra in the system K–Na–Ca–Li–Be–Mg–Mn–Fe–Co–Ni–Zn–Al–Ti–Si–H, determined by multiple linear regression analysis on a data set of 111 published end‐member thermodynamic properties. The large number of polyhedra determined allows calculation of a much larger variety of phases than was previously possible, and the choice of constituents together with the large number of thermodynamic input data results in estimates with associated uncertainty of generally <5%. The quality of the data appears to be sufficiently accurate for thermodynamic modelling as demonstrated by modelling the stability of margarite in the CASH system and the position of the talc–staurolite–chloritoid–pyrope absent invariant point in the KMASH system. In both cases, our results overlap within error with published equivalents.     

流体的热力学前缘研究

总结了当前国内外关于流体的热力学前缘研究领域如下：（１）流体体系的ｐ－Ｖ－Ｔ－ｘ相关系研究，主要对象是Ｈ２Ｏ－ＣＯ２－盐类多组分体系高温高压下相图的实验和理论研究。（２）矿物在流体中的溶解度及溶解后在流体中溶解类型的形式和热力学性质——平衡常数（或Ｇｉｂｂｓ自由能）及各种偏摩尔性质的研究。（３）流体热力学模型化研究，已研制出大量的计算机软件，包括多种矿物、溶解类型的热力学数据库和模拟热液平衡、矿物溶解性质、反应路径和水—岩相互作用的实用程序。（４）超临界流体的相关系和化学反应等有许多特殊的性质，对认识地球内部的演化将有重要意义。（５）新技术新方法的发展，使分析单个矿物包裹体成分变成了现实。     

Thermodynamic description of aqueous nonelectrolytes at infinite dilution over a wide range of state parameters

A new, virial-like equation of state (EoS) for describing the thermodynamic properties of aqueous nonelectrolytes at infinite dilution is proposed. It is based on the accurate EoS for a solvent (H₂O) given by Hill (1990) and requires only three empirical parameters to be fitted to experimental data, and these are independent of temperature and pressure. Knowledge of the thermodynamic properties of a pure gas, together with these three parameters, enables prediction of the whole set thermodynamic properties of the solute at infinite dilution (chemical potential, entropy, molar volume, and apparent molar heat capacity) over a wide range of temperatures (0 to 500°C) and pressures (1 to 2000 bars), including the near-critical region. In the cases in which experimental thermodynamic data are lacking, the empirical parameters can be estimated solely from the known standard-state properties of the solute. The new EoS is compatible with the Helgeson-Kirkham-Flowers model for aqueous electrolytes, and thus it can be applied to reactions involving minerals, gases, and aqueous ions, in addition to uncharged species.     

矿物热力学数据的获取

简介矿物热力学数据获取方法发展现状,重点评述量热法和相平衡法的近期发展状况。     

A new method to calculate end-member thermodynamic properties of minerals from their constituent polyhedra I: enthalpy, entropy and molar volume

The thermodynamic properties of silicate minerals can be described as a linear combination of the fractional properties of their constituent polyhedra. In contrast, given the thermodynamic properties of these polyhedra, the thermodynamic properties of minerals can be estimated, where only the crystallography of the mineral needs to be known. Such estimates are especially powerful for hypothetical mineral end‐members or for minerals where experimental determination of their thermodynamic properties is difficult. In this contribution the fractional enthalpy, entropy and molar volume for 35 polyhedra have been determined using weighted multiple linear regression analysis on a data set of published mineral thermodynamic properties. The large number of polyhedra determined, allows calculation of a much larger variety of phases than was previously possible and the larger set of minerals used provides more confident fractional properties. The OH‐bearing minerals have been described by partial and total hydroxide coordinated components, which gives better results than previous models and precludes the need of a S–V term to improve estimates of entropy. However, the fractional thermodynamic properties only give adequate results for silicate minerals and double oxides, and should therefore not be used to estimate the properties of other minerals. The thermodynamic properties of ‘new’ minerals are calculated from a linear stoichiometric combination of their constituent polyhedra, resulting in estimates generally with associated uncertainty of <5%. The quality of such data appears to be of sufficient accuracy for thermodynamic modelling as shown for meta‐bauxites from the Alps and the Aegean, where the effect of Zn on the P–T stability of staurolite can be both qualitatively and quantitatively reproduced.     

黄铁矿霍尔效应测量及载流子参数标型

用范德保法研制了半导体矿物霍尔系数及电阻率测量设置。阐述了天然半导体矿物样品通常具有质地甚不均匀、性质参数变化范围甚大等特殊性及与此有关的霍尔效应测量技术要点。以山东省东部乳山地区９个石英脉型金矿床黄铁矿的霍尔效应测量及其标型研究为例,首次提出了黄铁矿载流子参数标型特征及在预测金矿床成矿规模、矿物学填图等方面的应用意义。     

Semi-empirical Gibbs free energy formulations for minerals and fluids for use in thermodynamic databases of petrological interest

The P–T partition function in statistical thermodynamics can be used to derive semi-empirical formulations of the Gibbs free energy G for minerals and fluids. Parameterization of these equations includes simultaneous regression of experimental heat capacity and molar volume data, allowing fitting, appraisal and optimization of various data sources, as required in the construction of internally consistent petrological data bases. This approach can also be extended to minerals with -transitions and to fluids by considering the Gibbs free energy as a function of pressure P, temperature T and an ordering parameter X, so that accurate modelled representation and extrapolation of the thermodynamic properties of large numbers of petrologically significant minerals and coexisting fluids can be attained. The ordering parameter is chosen to denote the equilibrium mole fraction (thermodynamic probability) of ordered clusters (structural units) in a substance when G(T,P, X)=min. The procedure is tested on existing experimental data for the system MgO–SiO₂–H₂O. The proposed Gibbs free energy formulation permits thermodynamic properties of minerals, fluids and phase equilibria to be described and extrapolated over a wide range of pressure (0–800 kbar) and temperature (20–3000 K), thus allowing effective use in thermodynamic data bases of petrological interest.     

Thermodynamic properties of San Carlos olivine at high temperature and high pressure

In this study, the thermal expansion and heat capacity of San Carlos olivine under high temperature and high pressure are reported. Combining accurate sound velocity data under different P–T conditions with density and heat capacity data at ambient pressure, the density, adiabatic bulk modulus, shear modulus, and most importantly, thermal expansion and heat capacity, of San Carlos are extracted to 14 GPa by a numerical procedure using classic thermodynamic relationships. These data are in agreement with published findings. To estimate the temperature gradient in the upper mantle, we also report the fitting equations of thermal expansion and heat capacity of San Carlos olivine as a function of both temperature and pressure to the P–T condition of the 410 km discontinuity, which provide the thermodynamic properties with increasing depth in the Earth’s interior.     

非理想热力学混合作用对固溶体矿物热容的影响——以斜方顽火辉石-正铁辉石固溶体为例

斜方顽火辉石-正铁辉石(MgSiO_3-FeSiO_3)中Fe~(2+)及Mg~(2+)在M_1和M_2两种非等效位置上进行非理想混合。研究表明,辉石的等压热容(C_p)强烈依赖于组成,呈非线性关系,可表示为: 低温时热容的非理想混合效应显著,随着温度的升高,等温热容曲线(空间热容曲面)从一个极大值点(峰脊)分解为两个极大值点(峰脊),且逐渐趋向于理想混合热容直线(或平面)。