山东招远罗山金矿控矿断裂成因,演化及其意义     

章增凤  张亚雄 《华东地质学院学报》1989,12(3):13-21

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怀安蔓菁沟早前寒武纪高压麻粒岩混杂岩带地质特征、岩石学和同位素年代学   总被引：11，自引：19，他引：11  

郭敬辉  翟明国  张毅刚  李永刚  阎月华  张雯华 《岩石学报》1993,(4)

华北克拉通北缘中段怀安蔓菁沟高压麻粒岩混杂岩带产在太古宙怀安杂岩南缘与花岗岩带交界处,由高压基性麻粒岩、辉长质麻粒岩、英云闪长质麻粒岩和少量夕线石榴片麻岩相间排列的席状岩层构成,岩层间被高应变带或剪切带分隔。高压基性麻粒岩是石榴辉石麻粒岩。据石榴石斑晶内包裹的早期矿物(Cpx+Q)估算的早期高压变质作用条件:T=800℃,P>1.4GPa。环绕斑晶的后成合晶反应边矿物组合(P1+Opx+Hb+Cpx)的变质条件为:T=820℃,P为0.7～0.9GPa。全岩Sm-Nd等时线年龄2.65Ga,矿物Sm-Nd等时线年龄1.82Ga,锆石U-Pb一致线年龄1.83Ga。高压基性麻粒岩的原岩代表晚太古代陆壳的最下部,大约在2.7Ga从上地幔分异出来,可能经壳下垫托作用加在早期陆壳底部,随后经历高压变质作用。早元古代晚期,由于地壳规模的大型逆冲作用,使其上升,并经受褶皱形变、剪切推覆和退变质等作用的改造,形成高压麻粒岩混杂岩带。  相似文献   

三山岛金矿F3断裂带的水文地质工程地质特征及灾害防治   总被引：2，自引：0，他引：2  

张寿全  黄巍 《工程地质学报》1994,2(1):62-72

本文对三山岛金矿F3断裂带的构造、岩性和水动力学特征进行了研究,对矿坑开挖中的突水和坑道碎屑流的成因做了探讨,并在水文地质结构、水化学、水同位素及水文地热学的综合研究基础上,对未来的二期井下工程开挖中可能出现的工程地质问题进行了预测,提出了防治方案。  相似文献   

河北张－宣金矿区含金石英脉⁴⁰Ar/³⁹Ar年龄   总被引：19，自引：1，他引：19       下载免费PDF全文

胡达骧  罗桂玲 《地质科学》1994,29(2):151-158

为解决张-宣地区含金石英脉形成的时代,对区内5个典型金矿脉测定了⁴⁰Ar/³⁹Ar年龄,分别为:1362.0±24.8Ma,963.7±22.3Ma,579.6±8.5Ma,570.8±24.2Ma,167.9±1.2Ma.谱线特征均为马鞍形,最低视年龄为石英的结晶年龄。依次相当于晋宁运动中期,晋宁运动晚期,蓟县运动晚期和燕山运动中期。  相似文献   

广西水岩坝矿田成矿构造演化及脉型矿床的构造控矿机制研究   总被引：2，自引：1，他引：2  

谢国源  胡火炎 《大地构造与成矿学》1994,18(1):75-83

位于桂东北姑婆山复式岩体西南接触带的水岩坝锡钨矿田，其主要矿床在控矿因素上具有以构造控矿为主导因素的特点，本文通过对矿田内主干断裂的岩组运动学、动力学及变形岩石有限应变分析。对本区自地洼区阶段以来，燕山期花岗岩体的侵入所造成的矿田构造格局进行了系统的研究；然后．根据烂头山黑钨石英脉型矿床的特征，按脆－韧性剪切的原理，从递进变形的角度指出本区脉型矿床的成矿规律．模式和找矿方向，并提出该矿床为构控型多因复成矿床。  相似文献   

小秦岭石英脉（构造带）含金性评价的包裹体指标研究     

卿敏  白万成 《黄金地质》1995,1(3):54-60

选择了小秦岭含金石英脉脉石英的显微镜下特征、红外光谱及近脉（矿）围岩全岩爆裂温测等３种包裹体研究方法，对比研究了东闯金、铅矿区和杨砦峪矿区不同含金性石英脉、含矿脉中的富矿、贫矿地段及矿体不同部位的包裹体特征，提出出了石英脉含金性评价及差别矿体剥蚀程度的包裹体指标。  相似文献   

高密度电阻率法在东安金矿床勘探中的应用     

张海心  杨言辰 《吉林地质》2005,24(4):76-79

本文论述了高密度电阻率法在逊克县东安岩金矿床勘探中的应用效果;阐明了该方法在地质勘查中解决高阻脉状金矿体产状及埋深的技术手段.  相似文献   

胶东脉型金矿定量统计模型   总被引：1，自引：0，他引：1  

陈国华  刘连登  吴国学  杨峰  仇广乐  张辉煌 《黄金地质》2001,7(4):33-40

胶东存在中深成和浅成两类脉型金矿。定量统计模型研究发现，形成于 挤压地球动力学环境的中深成脉型金矿，成矿深度相对深，规模大，矿化强，形成于拉张地球动力学环境的浅成脉型金矿，成矿深度相对浅，规模小，矿化弱。  相似文献   

Phosphorus oxynitride PON, a silica analogue: structure and compression of the cristobalite-like phase; P –T phase diagram     

J. M. Léger  J. Haines  C. Chateau  G. Bocquillon  M. W. Schmidt  S. Hull  F. Gorelli  A. Lesauze  R. Marchand 《Physics and Chemistry of Minerals》2001,28(6):388-398

 The structure of the cristobalite-like polymorph of phosphorus oxynitride PON has been refined using neutron powder diffraction data. It is tetragonal, space group I&4macr;2d, Z=4. The four P–(O,N) distances are equal but the tetrahedron is compressed along c. In AX₂ or ABX₄ compounds, the tetragonal I&4macr;2d or I&4macr; structure is obtained when the average ratio of the cation to anion radius is below 1.186, whereas the tetragonal P4₁2₁2 or orthorhombic C222₁ structure is obtained at low temperatures for larger ratios. The cell parameters of this PON polymorph have been determined as a function of hydrostatic pressure by in situ angle dispersive X-ray powder diffraction in a diamond-anvil cell. Under truly hydrostatic pressure, a strong anisotropic behavior is observed with the c parameter being nearly incompressible. Very slight anisotropic stress strongly modifies the high-pressure behavior. According to the pressure-temperature conditions of treatment, three phases, cristobalite-, moganite-, and quartz-like, have been obtained by quenching experiments, and the P–T phase diagram of PON was derived. The high-pressure behavior of the α-quartz, moganite, and cristobalite-like polymorphs of PON and SiO₂ is discussed. Received: 7 August 2000 / Accepted: 21 January 2001  相似文献   

Location and quantitative analysis of OH in coesite     

M. Koch-Müller  Y. Fei  E. Hauri  Z. Liu 《Physics and Chemistry of Minerals》2001,28(10):693-705

 The incorporation of hydrogen (deuterium) into the coesite structure was investigated at pressures from 3.1 to 7.5 GPa and temperatures of 700, 800, and 1100 °C. Hydrogen could only be incorporated into the coesite structure at pressures greater 5.0 GPa and 1100 °C . No correlation between the concentration of trace elements such as Al and B and the hydrogen content was observed based on ion probe analysis (1335 ± 16 H ppm and 17 ± 1 Al ppm at 7.5 GPa, 1100 °C). The FTIR spectra show three relatively intense bands at 3575, 3516, and 3459 cm⁻¹ (ν₁ to ν₃, respectively) and two very weak bands at 3296 and 3210 cm⁻¹ (ν₄ and ν₅, respectively). The band at 3516 cm⁻¹ is strongly asymmetric and can be resolved into two bands, 3528 (ν_2a) and 3508 (ν_2b) cm⁻¹, with nearly identical areas. Polarized infrared absorption spectra of coesite single-crystal slabs, cut parallel to (0 1 0) and (1 0 0), were collected to locate the OH dipoles in the structure and to calibrate the IR spectroscopy for quantitative analysis of OH in coesite (ɛ _{i ,tot}=190 000 ± 30 000 l mol⁻¹ _H2O cm⁻²). The polarized spectra revealed a strong pleochroism of the OH bands. High-pressure FTIR spectra at pressures up to 8 GPa were performed in a diamond-anvil cell to gain further insight into incorporation mechanism of OH in coesite. The peak positions of the ν₁, ν₂, and ν₃ bands decrease linearly with pressure. The mode Grüneisen parameters for ν₁, ν₂, and ν₃ are −0.074, −0.144 and −0.398, respectively. There is a linear increase of the pressure derivatives with band position which follows the trend proposed by Hofmeister et al. (1999). The full widths at half maximum (FWHM) of the ν₁, ν₂, and ν₃ bands increase from 35, 21, and 28 cm⁻¹ in the spectra at ambient conditions to 71, 68, and 105 in the 8 GPa spectra, respectively. On the basis of these results, a model for the incorporation of hydrogen in coesite was developed: the OH defects are introduced into the structure by the substitution Si^4+(Si2)+4O²⁻= ^[4]□^(Si2) + 4OH⁻, which gives rise to four vibrations, ν₁, ν_2a, ν_2b, and ν₃. Because the OH(D)-bearing samples do contain traces of Al and B, the bands ν₄ and ν₅ may be coupled to Al and/or B substitution. Received: 19 December 2000 / Accepted: 23 April 2001  相似文献