岩石电容:物探"激发极化"的实质 ——对于物探"激发极化"一次和二次电压现象的讨论

利用岩石、地质体的电容特性论证“激发激化”（IP）一次和二次电压的形成机理,指出了假说状态的IP理论错误,使得一次和二次电压现象能够科学地应用到地球物理勘探.根据实际的电阻都具有电容的特性以及实际的电容都“漏电”的事实,推定同样是电阻的岩石、地质体具有电容特性.利用岩石、地质体的电阻电容等效电路验证了岩石、地质体充放电过程中产生一次电压和二次电压,且一次和二次电压的和等于充电稳定时的电压的事实;在交流充电中,利用该等效电路同样验证了电流与电压间的相位移及阻抗的减小现象,并得到实测数据证明;利用实测数据,通过综合分析方法推断出等效电路推导的一次和二次电压与实测相符.岩石、地质体具有电容特性,实际上是体现了岩石具有电容这一物性特征.研究结果显示,一次二次电压的形成不存在“激发”因素,IP理论中的“极化率”大小与极化没有关系.研究表明,一次和二次电压的关系可以反映岩石、地质体内金属矿物的含量;利用岩石、地质体的充放电的时间常数、电容特性进行物探,对于识别隐伏地质体,效果会更好.     

无外加流体、350℃和差异应力条件下硫化物再活化实验研究

红透山块状硫化物矿石主要成分为黄铁矿、磁黄铁矿、黄铜矿、闪锌矿和石英、角闪石、黑云母等脉石矿物。将此矿石烘干后作为试料置于岩石三轴应力试验机,在13h内将轴压、围压和温度分步升至1276MPa、414MPa和350℃,然后在空气中自然冷却至室温。实验产物中黄铁矿、石英、长石等以脆性碎裂为主,而磁黄铁矿、黄铜矿、闪锌矿和云母等以塑性变形为主。再活化的黄铜矿、磁黄铁矿和少量闪锌矿呈脉和网脉穿插黄铁矿碎斑。实验结果表明,即使没有外来流体加入．构造动力作用所导致的流体包裹体破坏所释出的流体,就足以使成矿物质发生活化转移和再活化。     

热磁技术确定矿床有效指示元素的试验与效果

针对找矿指标的有效性和找矿模型的普适性问题,研究引入热磁技术,以乌努格吐山铜矿和丰山洞铜矿为例,对比分析了土壤热磁组分与岩石、岩石热磁组分与黄铁矿的元素组合。试验表明,在确定成矿指示元素组合方面,土壤热磁组分是一种可行的介质,相比岩石具有更高的元素含量,可以挖掘出更多的异常信息;而岩石热磁组分与黄铁矿则具有一致的元素组合,比较而言,岩石热磁组分具有更宽的适用范围(如风化岩石)。作为一种人工方法分离组分,热磁组分弥补了岩石或黄铁矿等自然介质本身所固有的一些不足,为成矿指示元素的选择提供了一个新的研究平台;对于确定同一类型矿床有效指示元素组合,解决找矿模型的普适性问题,开拓了一种新思路。     

基于电容率法的矿藏勘探新方法研究

重点介绍了NaC l溶液的电容随着溶液矿化度、测量极板之间的距离以及测量频率的变化规律。结果表明,在直接测量电容的情况下,NaC l溶液的电容随着极板距离的增加按负平方关系减小;随着溶液浓度的增加按平方关系增加;随着频率的增加按负幂指数规律减小。通过和NaC l溶液电阻的对比发现,同样的条件下,电容的变化率比电阻明显,这将有助于地层流体的识别,尤其是目前大量存在的水淹油气层、低阻油气层和薄油层。基于以上结论,提出了第二介电常数的概念,第二介电常数不同于传统介电常数的关键之处在于:第二介电常数是直接测量介质的介电特性,而不是将其置于极板之间进行测量。还指出,在进行交流电测井时,地层的电容信号也同样能反映出地层及其孔隙流体的特征,在此基础上提出了电容率法测井的想法,即在测量地层电阻率的同时,还要进行电容率的测量,来反映地层及其孔隙流体电容率的信息。此外,还提出了两电极法进行地面电容率勘探的设想,这种方法不仅能够用于找油找气,还可以探测金属矿藏。     

四川省拉拉铜矿床含金性及金的赋存状态研究

根据对拉拉铜矿床的矿石结构、构造及矿物共生组合的研究，发现矿石中含有大量自然金和含铂族元素的碲化物。自然金的赋存状态为包裹休金、粒间金、裂隙金。主要的载金矿物有黄铜矿、黄铁矿、叶碲铋矿，含金性最好的岩石类型为只云母钠长片岩。金与成矿元素铜的关系最为密切。     

广西荔浦龙窝铜矿地质特征与控矿因素初探

文章在总结龙窝铜矿矿床地质特征的基础上,初步探讨铜矿的控矿因素,认为下泥盆统莲花山组是龙窝铜矿主要的含矿地层,紫红色砂岩为有利的容矿岩石;近NE—SW向断裂,褶皱构造的转折端、倾伏端及两翼是重要的成矿部位;硅化、黄铁矿化、绢云母化为明显的铜矿化围岩蚀变标志。     

内蒙古科右前旗保隆南沟—老敖沟银矿化带岩石特征及其指示意义

内蒙古科右前旗保隆南沟—老敖沟一带银矿受断裂构造控制,矿体多呈脉状,赋存于上侏罗统玛尼吐组和侏罗纪花岗岩体的蚀变岩中.矿化岩石的主要蚀变有钾化、电气石化、绢云母化、硅化、绿泥石化、绿帘石化等.矿石矿物主要有辉银矿、方铅矿、闪锌矿、毒砂、辉钼矿、辉铋矿、黄铁矿、黄铜矿、磁铁矿、褐铁矿等.通过对矿体地质特征、矿化蚀变、矿化...     

四川省冕宁庙顶铜金矿床地质与矿物学特征及成矿意义

庙顶铜金矿床位于特提斯成矿域与滨太平洋成矿域交界部位,处于多个成矿远景区的交汇地带,成矿条件优越。矿体赋存于泥盆系碳酸盐化凝灰岩、泥质粉砂质板岩、碳酸盐化泥晶灰岩与二叠系变质玄武岩地层中。岩相学表明:矿床的矿石类型有铜金矿化碳酸盐石英脉型、铜金矿化变质岩型和铜矿化钠长石岩型。矿相学研究表明:铜矿物以硫化型为主,其次为氧化型,主要为黄铜矿,其次是斑铜矿及铜蓝;金赋存以含银自然金为主,其次为银金矿,游离金为主要的回收对象。金属矿物的生成顺序为:磁铁矿→黄铁矿→自然金、银金矿、黄铜矿、斑铜矿、辉铜矿、黝铜矿、磁黄铁矿→方铅矿、铜蓝、蓝辉铜矿→褐铁矿、孔雀石、蓝铜矿、氯铜矿。矿床形成经历了变质期、热液期和表生期,其中热液期又分为3个阶段:钠长石-云母-黄铁矿阶段(Ⅰ)、金-石英-多金属硫化物阶段(Ⅱ)和碳酸盐-石英-重晶石阶段(Ⅲ)。电子探针结果表明,矿床的形成过程经历了由高温到低温的变化,成因类型应属岩浆热液矿床。     

俄罗斯堪察加中部Baranevskoy金-银矿床矿物学与流体包裹体研究

Baranevskoy金-银矿床产于巴尔喀什火山的火山口,该火山坐落在堪察加中部矿区东南部。本文基于矿物学原理和流体包裹体数据分析探讨了Baranevskoy金-银矿床的成矿环境及其物理化学条件。Baranevskoy金-银矿床的围岩为中新世—上新世的安山岩和玄武岩。热液蚀变活动随深度逐渐变化,从而可以进一步划分出最深部的石英带、中部的石英-绢云母(明矾石)-黄铁矿-铁钛氧化物带及其伴生的石英-绢云母-伊利石-黄铁矿矿物组合和浅部的石英-冰长石-水云母-黏土矿物-碳酸盐岩带。成矿早期存在密集浸染的铜矿化,主要矿石矿物有黄铜矿、斑铜矿、砷黝铜矿-黝铜矿,并在Rhzavaya矿脉中存在少量的自然金。其中砷黝铜矿-黝铜矿系列以砷黝铜矿和黝铜矿两个端员作为代表,且以黝铜矿为主。成矿后期产出代表晚期金-银矿化的自然金、黄铁矿、黄铜矿、闪锌矿、方铅矿、碲化物和硫酸盐等标志性矿物。早期铜矿化(第一期)被认为是中硫阶段,紧随其后的为低硫型金-银矿化(第二期和第三期)。金从第一期到第三期都有沉淀。经研究发现,自然金也赋存于变质围岩的岩石裂隙内。早期的自然金相对富银,其中金的摩尔分数为59%~65%,低于后期(第二、第三期)自然金中金的摩尔分数(64%~72%)。流体包裹体显微测温结果显示,位于中部(Central)矿脉的包裹体均一温度为190~280 ℃,Rzhavaya矿脉的包裹体为190~240 ℃,产出自然金的蚀变围岩中石英的包裹体温度为230~310 ℃。包裹体总体表现出低盐度(0.9%~2.4% NaCl_eq)特征,推测存在大气水的混入。     

东昆仑石头坑德镍矿床岩石矿物特征

青海石头坑德是近年来发现的镍矿床,赋矿岩石为辉长岩、辉石岩相和橄榄岩相;矿石金属矿物主要为磁黄铁矿、镍黄铁矿、黄铜矿、黄铁矿、磁铁矿。矿石主要为交代粒状结构,海绵陨铁状,块状构造。该文中对石头坑德镍矿床和夏日哈木超大型镍矿的主要岩石矿物组合和矿石矿物组合作了比较,表明石头坑德镍矿具有形成大型-超大型规模矿床的有利条件。     

Alteration and mineral zonation at the Mt Lyell copper–gold deposit,Tasmania

The Mount Lyell copper deposits are located in the middle Cambrian Mount Read volcanic belt of western Tasmania and consist of more than 24 separate copper–gold–silver orebodies. The dominant copper mineralisation style is disseminated pyrite–chalcopyrite subvertical pipes with subordinate chalcopyrite–bornite ± other copper phases, massive pyrite and base metal sulfides. A zonation in mineralisation style within the pipes is defined from chalcopyrite–magnetite at depth to chalcopyrite–pyrite at intermediate levels, to chalcopyrite–bornite at the shallowest level. Alteration is developed broadly symmetrically around the ore zones and zoned from quartz–chlorite–phengite ± biotite at depth to quartz–muscovite at intermediate levels, and a quartz–muscovite–pyrophyllite–zunyite assemblage at the shallowest levels. This is interpreted to be a result of a fluid that evolved from hot, reduced and neutral conditions at depth to cool, oxidised and acidic conditions at the shallowest level. The chalcopyrite–bornite deposits occur at the top of the hydrothermal system and are associated with intensely silicified rock and muscovite/pyrophyllite alteration. The close relationship of these deposits with the top of the pipes suggests they are part of a single mineralising event. Where the chalcopyrite–bornite deposits are juxtaposed with the Owen Group, rather than a simple chalcopyrite–bornite mineralogy, there are numerous other copper phases, which represent higher oxidation states and collectively suggest variable and fluctuating fluid conditions during deposition. It is proposed that these deposits are formed by an interaction of the reduced hydrothermal fluid with an oxidised fluid generated at very shallow levels within and during deposition of the Owen Group. Mineralisation within the middle Owen Group sandstones and clasts of altered rock within the middle and upper Owen Group sediments marks the end of the hydrothermal system. Around the entire edge of the Mt Lyell field, there is a variation in the white mica composition from proximal muscovite to distal phengite that represents the neutralisation of the hydrothermal fluid by fluid–wall rock interaction.     

First Find of Ga-Bearing Minerals in Ores of Ural Massive Sulfide Deposits

Gallium-containing chlorite, mica, and magnetite (up to 14, 13, and 5–7 wt % of Ga) along with Ga hydroxides (oxyhydroxides?) were found for the first time in massive sulfide deposit in the Urals. The minerals identified within the cement of chalcopyrite–sphalerite breccias of the Shemur copper–zinc–massive sulfide deposit (Northern Urals) are associated with Ga-enriched sphalerite, chalcopyrite, and, less commonly, pyrite (33–364, 67–363, and 4–230 g/t, respectively).     

Measurement of rock mass deformation with grouted coaxial antenna cables

Summary Techniques presented herein show how reflected voltage pulses from coaxial antenna cable grouted in rock masses can be employed to quantify the type and magnitude of rock mass deformation. This measurement is similar to that obtained from a combined full profile extensometer (to measure local extension) and inclinometer (to measure local shearing). Rock mass movements deform the grouted cable, which locally changes cable capacitance and thereby the reflected wave form of the voltage pulse. Thus, by monitoring changes in these reflection signatures, it is possible to monitor rock mass deformation.This paper presents laboratory measurements necessary to quantitatively interpret the reflected voltage signatures. Cables were sheared and extended to correlate measured cable deformation with reflected voltage signals. Laboratory testing included development of grout mixtures with optimum properties for field installation and performance of a TDR (Time Domain Reflectometry) monitoring system. Finally, the interpretive techniques developed through laboratory measurements were applied to previously collected field data to extract hitherto unrealized information.     

Field Measurement of Suction, Water Content, and Water Permeability

This paper presents a review of techniques for field measurement of suction, water content, and water hydraulic conductivity (permeability). Main problems in the use of field tensiometers are addressed and hints on how to improve tensiometer performance are given. Advantages and limitations of instruments for indirect measurement of suction including electrical conductivity sensors, thermal conductivity sensors, dielectric permittivity sensors, filter paper, and psychrometer are discussed. Techniques for water content measurement based on dielectric methods are then presented. These include time and amplitude domain reflectometry and capacitance. Finally, a brief overview of methods for measurement of water permeability in the field is presented.     

广西龙围地区石英脉型铜矿中硫化物Re-Os测年及意义

广西大瑶山西北地区有大量的石英脉型铜矿出露,然而缺少相关矿床年龄的研究。为解决该问题,选取广西金秀龙围地区石英脉型铜矿床矿石中的黄铁矿和黄铜矿,进行Re-Os同位素测年研究,获得了加里东期的黄铁矿等时线年龄(417±25) Ma(MSWD=0.92)和印支期的黄铜矿等时线年龄(243±18) Ma(MSWD=0.45)。黄铁矿结晶明显早于黄铜矿,加里东期是否存在成矿事件还需要进一步研究。结合岩石矿物学分析,我们认为龙围地区铜矿床中矿石的形成,经历了黄铁矿结晶、黄铁矿碎裂和含铜热液在印支期充填交代等过程,最终固结成矿。研究厘定了龙围地区铜矿的成矿时间,并为大瑶山西北地区存在印支期成矿热液活动提供了证据。     

The Crater Mountain Deposit,Papua New Guinea: Porphyry‐related Au–Te System

Ore mineralization and wall rock alteration of Crater Mountain gold deposit, Papua New Guinea, were investigated using ore and host rock samples from drill holes for ore and alteration mineralogical study. The host rocks of the deposit are quartz‐feldspar porphyry, feldspar‐hornblende porphyry, andesitic volcanics and pyroclastics, and basaltic‐andesitic tuff. The main ore minerals are pyrite, sphalerite, galena, chalcopyrite and moderate amounts of tetrahedrite, tennantite, pyrrhotite, bornite and enargite. Small amounts of enargite, tetradymite, altaite, heyrovskyite, bismuthinite, bornite, idaite, cubanite, native gold, CuPbS₂, an unidentified Bi‐Te‐S mineral and argentopyrite occur as inclusions mainly in pyrite veins and grains. Native gold occurs significantly in the As‐rich pyrite veins in volcanic units, and coexists with Bi‐Te‐S mineral species and rarely with chalcopyrite and cubanite relics. Four mineralization stages were recognized based on the observations of ore textures. Stage I is characterized by quartz‐sericite‐calcite alteration with trace pyrite and chalcopyrite in the monomict diatreme breccias; Stage II is defined by the crystallization of pyrite and by weak quartz‐chlorite‐sericite‐calcite alteration; Stage III is a major ore formation episode where sulfides deposited as disseminated grains and veins that host native gold, and is divided into three sub‐stages; Stage IV is characterized by predominant carbonitization. Gold mineralization occurred in the sub‐stages 2 and 3 in Stage III. The fS₂ is considered to have decreased from ～10^?2 to 10^?14 atm with decreasing temperature of fluid.     

南宁膨胀土的体积含水率-等效介电常数关系

体积含水率-介电常数关系是时域反射法（TDR）测量土体体积含水率的理论基础。通过对重塑的南宁膨胀土进行试验,选择经验公式法、边界法及理论模型法模拟其体积含水率-等效介电常数的变化规律。研究发现,南宁膨胀土的实测值落在Hashin-Shtrikman边界和Wiener边界以内,但Hashin-Shtrikman边界具有更小的范围;由于膨胀土的黏性较大,结合水存在显著的影响,Topp公式计算值偏高,但采用考虑三相组分含量的Looyenga公式可反映结合水的影响,从而得到更好的结果;理论模型法的Maxwell-Garnett模型和差分有效介质模型（DEM）需要考虑三相的构成,单独采用气相连续或水相连续的模拟结果均不理想,但如考虑土中水、气分布形态,采用饱和度作为权重函数对单相计算结果进行加权平均后可取得较好的效果。     

Four Chinese Sulfide Mineral Reference Materials: Preparation and Certification

Four sulfide mineral reference materials, pyrite GSM-1, chalcopyrite GSM-2, galena GSM-3 and sphalerite GSM-4, have been prepared by the Institute of Rock and Mineral Analysis for collaborrative studies on their chemical composition. This paper describes the sample collection, preparation, homogeneity testing and interlaboratory certification of these samples. Some features with regard to the purification, pulverisation, stability and storage of sample are also discussed. The samples have been approved as certified reference materials by the State Bureau of Technical Supervision of China in April 1995.     

云南镇康芦子园铅锌铁多金属矿床矿石矿物特征及成因分析

镇康芦子园铅锌铁多金属矿床属大型铅锌铁矿床,对矿床矿石矿物的系统研究表明,矿石主要金属硫化物有闪锌矿、方铅矿、黄铜矿、黄铁矿。根据矿床地质特征、矿物共生组合及相互穿插关系,认为成矿主要分为热液成矿期和表生期,矿床是与燕山期隐伏岩体有关的岩浆热液型矿床。     

微扰法测量干燥岩矿样品复介电常数

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