泗滨砭石的岩石矿物研究Ⅰ:岩石化学和岩石结构特征与红外发射功能的关系

泗滨砭石是中医用以制造砭具的一种石材,加热后的砭具对人体有加快血液流动和疏通经络等明显的理疗效果.本文用近代岩石学分析测试技术,研究和测定了砭石的微结构、化学组成、放射性和法向发射率.结果表明,泗滨砭石是一种致密的微晶粒状结构石灰岩,CaCO3的含量高达96%,不含有毒元素,放射性核素含量极低.镜下能观察到的其他矿物有黄铁矿、锐钛矿和石墨,粒径1-3μm,分散产于方解石的晶界间;砭石中未见生物残骸,有机碳含量仅为0.09%.在8-14 μm光谱区测定的法向发射率高达0.923,说明砭石具有很好的红外发射性能,而方解石高达86.73 J/K·mol的热容和微晶致密结构特征,是砭石具有良好热辐射性质和加热后对人体有明显理疗效果的岩石学基础条件.     

一种纳米粒级砭石的矿物学特征与成因

为探究一种灰黑色砭石的矿物学特征及成因,采用X射线粉晶衍射(XRD)、扫描电子显微镜(SEM)、热重-微商热重分析(TG-DTG)及激光诱导离解光谱(LIBS)等分析方法对其矿物组成、结构特征、热力学性质及化学成分进行分析。结果表明,灰黑色砭石主要组成矿物为方解石(>98%),并含有少量石英、云母、长石、黄铁矿及微量石墨(<2%)。晶面尺寸测试及SEM分析结果显示,以上矿物单晶粒径大多处于纳米级别,砭石中矿物主要以块状、棒状及片状等3种集合体形式存在。微晶石墨呈分散态赋存在砭石中是灰黑色砭石致色的主要原因,而石英、云母、长石、黄铁矿及石墨等杂质的存在、纳米级的结构特征和类质同象导致砭石中方解石的热解温度远低于标准的纯方解石。砭石中纳米级方解石微球粒及石墨和黄铁矿微晶的存在,说明纳米级灰黑色砭石的形成可能与微生物的活动密切相关。     

硼酸盐矿物的振动光谱研究：Ⅱ：红外光谱特征

本文通过观测在不同温度下加热过的硼酸盐矿物的红外光谱,并与喇曼光谱结果进行比较,讨论了红外光谱谱带的归属。结果表明,通过观测不同温度下加热过的样品的谱带特征有助于谱带的归属。     

硼酸盐矿物的振动光谱研究：Ⅰ：喇曼光谱特征

本文利用激光喇曼光谱研究了不同类型的硼酸盐矿物,讨论了它们的谱带特征及其归属。研究结果表明,具简单基团的喇曼光谱可以作出比较明确的归属,且与红外光谱结果一致,而同时具三、四配位硼的矿物,其配阴离子虽很复杂,各种谱带相互叠加,但仍可以对主要谱带作出初步的归属。     

尖晶石族矿物的热辐射性质研究

本文主要研究晶石族矿物在５０－６５０℃，２－４０μｍ波长范围内的红外光谱发射率和总发射率。文中共研究了三十余种尖晶石族矿物的发射率。测试结果表明，尖晶石族矿物的发射率的大小受其成分、晶体结构、温度和波长的制约。过渡族中的着色离子将大大增加矿物在红外短波段的发射率。     

矿物分子光谱学研究的一些热点问题

矿物分子光谱学研究的一些热点问题郭立鹤（中国地质科学院矿床地质研究所，北京１０００３７）关键词矿物，红外光谱，喇曼光谱地球科学研究的发展，对矿物、岩石成分、结构的研究程度要求愈来愈高。就成分而言，早在６０年代，人们已发现仅凭矿物、岩石的主成分远远不能...     

西北干旱地区氧化带硫酸盐矿物晶体化学研究取得新成果

兰州大学李万茂副教授等承担的国家自然科学基金资助项目“西北干旱地区氧化带硫(磷砷钒)酸盐矿物晶体化学研究”,已于1991年1月按计划园满完成。 三年来,通过对西北干旱地区具有代表性的锡铁山铅锌矿、白银厂小铁山多金属矿、照壁山铜矿等矿床氧化带的野外考察,采集了二百多个样品。经室内鉴定和分离,精选了130多个单矿物样品,进行了电子探针单矿物成分分析,X射线单晶结构和粉晶衍射分析,红外和喇曼光谱分析,穆斯堡尔谱分析,扫描电子显微镜和透射电镜分析,差热和热重分析,以     

X射线粉晶衍射仪在辽宁瓦房店金伯利岩蚀变矿物鉴定中的应用

瓦房店金伯利岩热液蚀变强烈,原岩矿物组分几乎蚀变殆尽,显微镜下对蚀变矿物鉴定相当困难.利用X射线粉晶衍射技术对蚀变金伯利岩物相进行系统检测,结果显示：42号岩管金伯利岩主要矿物为蛇纹石、金云母和滑石,有少量方解石、锐钛矿、磷灰石、石英、钛铁矿、钙钛矿、榍石、磁铁矿和绿泥石;石灰窑1号无矿金伯利岩岩管主要矿物为蛇纹石、金云母和白云石,有少量方解石、锐钛矿、磷灰石、滑石、磁铁矿和绿泥石;9号无矿金伯利岩岩脉主要矿物为方解石和石英,有少量绿泥石和重晶石;51号贫矿金伯利岩岩管主要矿物为蛇纹石和金云母,方解石化作用不均匀,白云石化作用普遍,有少量锐钛矿、滑石、磁铁矿、绿泥石、磷灰石、钛铁矿、石英;30号贫矿岩管样品风化严重,主要矿物为蒙脱石,有少量方解石、滑石、蛇纹石、榍石、磷灰石.实践证明,采用X射线粉晶衍射仪鉴定金伯利岩蚀变矿物组合是一种非常可行的技术手段.     

泗滨砭石的矿物组成特征及其与砭石理疗功能的关系

砭石疗法是我国古代具有悠久历史的医疗方法,具有疏通经络、条理气血等理疗功效,在《黄帝内经》中砭与针、灸、药、按蹻等并列为中医的五大医术.砭石疗法自东汉起失传.20世纪90年代,在岩石物理学家和中医专家的共同努力下,在山东泗水之滨重新发现了砭具佳石--泗滨砭石,提出了新砭石疗法[1-2].     

2：3的蒙皂石—云母间层矿物研究

2:3的蒙皂石-云母间层矿物产于含锰碳酸盐矿物中,与方解石、钙菱锰矿、菱锰矿、菱铁矿、黄铁矿、黄铜矿和锐钛矿共生。矿物呈片状和不规则粒状,颜色呈灰、灰白色和浅黄色,条痕灰白色。显微硬度78kg/mm~2、摩氏硬度1.5。比重2.58。比磁化系数3.35×10~(-6)C·G·S·M·cm~3=/g。主要X射线粉晶线是11.39(100),5.06(87),4.48(81),3.28(70)。矿物的红外吸收谱特征为:3600—3700,1000—1050,540,490cm~(-1),此外还对该矿物作了差热分析。     

A demonstration of an affinity between pyrite and organic matter in a hydrothermal setting

One of the key-principles of the iron-sulphur world theory is to bring organic molecules close enough to interact with each other, using the surface of pyrite as a substrate in a hydrothermal setting. The present paper explores the relationship of pyrite and organic matter in a hydrothermal setting from the geological record; in hydrothermal calcite veins from Carboniferous limestones in central Ireland. Here, the organic matter is accumulated as coatings around, and through, pyrite grains. Most of the pyrite grains are euhedral-subhedral crystals, ranging in size from ca 0.1-0.5 mm in diameter, and they are scattered throughout the matrix of the vein calcite. The organic matter was deposited from a hydrothermal fluid at a temperature of at least 200°C, and gives a Raman signature of disordered carbon. This study points to an example from a hydrothermal setting in the geological record, demonstrating that pyrite can have a high potential for the concentration and accumulation of organic materials.     

方解石-白云石-菱镁矿的中远红外光谱学特征研究

利用拉曼光谱和红外光谱研究了方解石、白云石和菱镁矿的光谱学特征,探究了影响三种矿物红外辐射性能的因素。三种矿物的拉曼光谱(Raman)、中红外吸收光谱(MIR)、远红外吸收光谱(FIR)显示随着矿物中镁含量的增大将会影响CO₃^2-的面外弯曲振动(ν₂)、反对称伸缩振动(ν₃)和平面内弯曲振动(ν₄),使各光谱特征峰均向高频端迁移。基于黑体辐射定律以及在80 ℃、400~2 000 cm^-1矿物的辐射能量谱,结果显示方解石、白云石、菱镁矿的发射率依次减少(0.951,0.938,0.895)。三种矿物的红外吸收光谱和发射光谱中的振动位置均受CO₃^2-基频的显著影响,在1 300~1 650 cm^-1均产生宽的低吸收带,该吸收带与CO₃^2-的反对称伸缩振动相关,且吸收带范围(202,236,272 cm^-1)与发射率之间呈负相关关系。因此,当最强化学键的振动出现在发射光谱窄的吸收带范围内会产生相对较高的辐射能和发射率。此外,矿物的晶体结构也会影响发射率,大的离子半径、键长和晶胞体积将降低辐射过程中能量的吸收,增强辐射特性。综上研究结果,方解石、白云石和菱镁矿的拉曼光谱和红外光谱揭示了金属原子的相对质量对光谱学特征的显著影响,其发射率可能受到C—O键的反伸缩振动范围、最强吸收带控制的最低发射率以及矿物晶体结构的共同影响。这项研究呈现了必要的光谱信息和热发射率数据以识别特定的碳酸盐矿物,为类似矿物的光谱特征研究奠定了基础;同时为进一步认识地壳中大量的碳酸盐矿物提供了研究方法,也为地外勘探的深入研究给予相关的理论基础。     

Pyrophanite pseudomorphs after perovskite in Perkupa serpentinites (Hungary): a microtextural study and geological implications

Pyrophanite in serpentinite at Perkupa (Hungary) is described in detail for the first time as a replacement product of perovskite. It occurs as a 20- to 30-μm-wide rim, mantling a remnant core composed of perovskite or its alteration products. The pyrophanite rim consists of an inner zone, representing a pseudomorph after perovskite, and an outer overgrowth zone. Raman mapping and electron backscatter diffraction data show that the pyrophanite rims typically represent single crystals rather than being composed of multiple domains in different crystallographic orientations. Perovskite occurs exclusively in the core of pyrophanite and was identified as the orthorhombic CaTiO₃ phase, based on Raman spectra. Heterogeneous, polyphase mineral cores, consisting of calcite, anatase and/or brookite, kassite, and Mn-bearing kassite, in some cases in association with relict perovskite, are typical in the larger pyrophanite-rimmed grains. The crystallographically coherent pyrophanite rims could have formed through a process where the precursor perovskite crystal acted as a structural template for the newly forming phase, that is, by interface-coupled dissolution reprecipitation during serpentinization of the precursor rock. This alteration of perovskite to pyrophanite was not complete, resulting in the presence of perovskite fragments enclosed in pyrophanite. During the metamorphic evolution of the rock, some of the remnant perovskite cores further altered to TiO₂ polymorphs (anatase and brookite) and calcite, via transitional alteration products.     

Cracking mechanisms during galena mineralization in a sandstone-hosted lead–zinc ore deposit: case study of the Jinding giant sulfide deposit, Yunnan, SW China

There are two types of lead–zinc ore bodies, i.e., sandstone-hosted ores (SHO) and limestone-hosted ores (LHO), in the Jinding giant sulfide deposit, Yunnan, SW China. Structural analysis suggests that thrust faults and dome structures are the major structural elements controlling lead–zinc mineralization. The two types of ore bodies are preserved in two thrust sheets in a three-layered structural profile in the framework of the Jinding dome structure. The SHO forms the cap of the dome and LHO bodies are concentrated beneath the SHO cap in the central part of the dome. Quartz, feldspar and calcite, and sphalerite, pyrite, and galena are the dominant mineral components in the sandstone-hosted lead–zinc ores. Quartz and feldspar occur as detrital clasts and are cemented by diagenetic calcite and epigenetic sulfides. The sulfide paragenetic sequence during SHO mineralization is from early pyrite to galena and late sphalerite. Galena occurs mostly in two types of cracks, i.e., crescent-style grain boundary cracks along quartz–pyrite, or rarely along pyrite–pyrite boundaries, and intragranular radial cracks in early pyrite grains surrounding quartz clasts. The radial cracks are more or less perpendicular to the quartz–pyrite grain boundaries and do not show any overall (whole rock) orientation pattern. Their distribution, morphological characteristics, and geometrical relationships with quartz and pyrite grains suggest the predominant role of grain-scale cracking. Thermal expansion cracking is one of the most important mechanisms for the generation of open spaces during galena mineralization. Cracking due to heating or cooling by infiltrating fluids resulted from upwelling fluid phases through fluid passes connecting the SHO and LHO bodies, provided significant spaces for crystallization of galena. The differences in coefficients of thermal expansion between pyrite and quartz led to a difference in volume changes between quartz grains and pyrite grains surrounding them and contributed to cracking of the pyrite grains when temperature changed. Combined thermal expansion and elastic mismatch due to heating and subsequent cooling resulted in the radial and crescent cracking in the pyrite grains and along the quartz–pyrite grain boundaries.     

Raman spectroscopy at high pressure and high temperature. Phase transitions and thermodynamic properties of minerals

An outline of recent developments in Raman spectroscopy at high pressure, high temperature and combined high pressure and high temperature is presented. The instrumental and technical aspects of Raman spectroscopy, and coupling of diamond anvil cells and miniature furnaces to Raman microspectrometers are discussed. Some potential pitfalls, such as the thermal pressure in laser heated diamond anvil cells or the thermal radiation during high-temperature measurements, are presented. Special emphasis is given on processing of high-temperature Raman data. New recently discovered phase transformations in the SiO₂ system (quartz→ quartz II, pressure-induced amorphization of quartz) and structural changes in SiO₂ glass and melt are used to infer the capability of in-situ Raman spectroscopy for determining the microscopic behaviour of minerals, melts and glasses under extreme pressure and temperature conditions. Finally, it is shown how vibrational mode anharmonicity can be obtained from the pressure- and temperature-induced shifts of Raman modes. This anharmonicity can be introduced into the vibrational modeling of the thermodynamic properties (entropy and equation of state) of minerals. The example of calcite is briefly discussed.     

TEM study of a silicate-carbonate-microbe interface prepared by focused ion beam milling

The biogeochemical alteration of an Mg-Fe orthopyroxene, reacted for 70 yr under arid conditions in a desert environment, was studied by transmission electron microscopy. For this purpose, an electron transparent cross-section of the interface between a single microorganism, an orthopyroxene and nanometer-sized calcite crystals, was prepared with a focused ion beam system. X-ray energy dispersive spectrometry and electron energy loss spectroscopy allowed one to clearly distinguish the microorganism en route to fossilization from the nanometer-sized calcite crystals, showing the usefulness of such a protocol for identifying unambiguously traces of life in rocks. A 100-nm-deep depression was observed in the orthopyroxene close to the microorganism, suggesting an enhanced dissolution mediated by the microbe. However, an Al- and Si-rich amorphous altered layer restricted to the area just below the microorganism could be associated with decreased silicate dissolution rates at this location, suggesting complex effects of the microorganism on the silicate dissolution process. The close association observed between silicate dissolution and carbonate formation at the micrometer scale suggests that Urey-type CO₂ sequestration reactions could be mediated by microorganisms under arid conditions.     

Graphite deformation in marble and mylonitic marble, Grenville Province, Canadian Shield

In the southern Grenville Province of the Canadian Shield (Otter Lake area), high-grade marble, gneiss and amphibolite have been folded about north- to north-east-trending axes; mylonite zones, parallel to layering and 0.1–10  cm wide, are locally present in marble.
In nonmylonitic marble, graphite occurs as c . 1–mm hexagonal prisms, which are commonly accompanied by a relatively few crystals that have been deformed, resulting in cleavage separation and the formation of folds and kink bands. Fracture-filled calcite contains less Mg and Fe than surrounding calcite (e.g. <0.30 compared with 1.8–2.7  wt% MgO, and 0.02–0.12 compared with 0.13–0.18  wt% FeO); the composition of fracture-filled dolomite is similar to that of the surrounding dolomite. In semimylonite, graphite forms elongate streaks of fragmented crystals and, in mylonite, further fragmentation has occurred to produce extremely small particles. The fragmentation has not destroyed the atomic structure (hexagonal modification) of graphite.
The behaviour of biotite was similar to that of graphite, but extreme fragmentation did not occur. Dolomite was more rigid than calcite, and in mylonite it occurs more commonly as relics. Amphibole and pyroxene crystals remained undeformed but are locally replaced by calcite.
The numerous microprocesses that have evidently occurred in marble and mylonitic marble of the study area are: coarsening (calcite, graphite), twinning (calcite, dolomite), slip (calcite, dolomite, graphite, biotite), strain-induced recrystallization (calcite), microfolding and kink-band formation (graphite, biotite), fragmentation (graphite) and the pressure-induced transport of calcite and dolomite to voids in graphite and biotite.     

Pyritized ooids,stringed ooids and reticulate tubular structures from within the black shale at Amjhor,Bihar, India

Carbonate ooids, notionally incompatible with an euxinic environment, and some curious reticulate tubular structures with fibrous carbonate walls are described from intraclasts occurring in Proterozoic black shales containing the pyrite deposit at Amjhor. While some of the tubes are visibly due to coalescence of ooids, others are interpreted as worm burrows on the basis of their strata-transgressive orientation, branching nature and larger diameter than those of the ooids.All stages of pyritization of ooids and tube-cores, displaying truncation of the growth-fabric of calcite grains by growing pyrite crystals, point to a late- or post-diagenetic age of pyritization. The clasts containing ooids and tubes are believed to have been transported from a shallow-bank and/or a nearshore environment into a lagoonal, euxinic basin. An environmental model, consistent with the observed data, is proposed to account for the ooid—black shale association.     

紫木凼金矿床载金矿物及金的赋存状态

紫木凼金矿床主要载金矿物为含砷黄铁矿和毒砂,氧化矿石中,金呈显微粒状自然金－显微金嵌布于褐铁矿,石英水云母,方解石的颗粒间或孔隙中,原生矿石中,金主要呈次显微粒自然金－次显微金包裹体,其次是类质同像形式赋存在含砷黄铁矿和毒砂矿物中。     

渤中凹陷北部陡坡带热液活动及其对湖相碳酸盐岩储层的影响

渤海海域渤中凹陷北陡坡带沙一段发育湖相碳酸盐岩及相关的混积岩类油藏,探明储量超亿方,产量高,埋深超过3 200~3 800 m.分析表明:湖相碳酸盐岩段及混积岩段发生了强烈的白云岩化作用,溶蚀作用强,储层物性好,孔隙度可超过25%.早期研究认为生屑的溶蚀是储层物性改善的重要因素.进一步研究表明,除了上述因素外,储层还受到了深部热流体的影响.通过包裹体激光拉曼分析证实,储层中存在大量含CO₂、N₂、H₂S、H₂的包裹体,CO₂最高含量超过70%;研究区多个构造富含CO₂,碳同位素及氦同位素显示其为幔源成因;对储层中大量的自生黄铁矿分析表明,大部分黄铁矿Co/Ni比值大于1,显示了热液成因;在缝洞及大孔隙内沉淀典型微晶鞍形白云石,具弧形晶面,波状消光,扫描电镜下鞍形白云石内见密集的生长纹.综合分析表明,富CO₂深部幔源热液侵位时间为3 Ma以来,侵位后造成了白云石晶间残余方解石的大量选择性溶解;酸性流体对粒内长石也产生了强烈的溶蚀作用,形成了大量砾石及岩屑的铸模孔并沉淀高岭石,流体上述溶解作用对储层段物性改善起到了决定性影响.随着方解石及长石的溶解,流体PH值的升高,盐度的增加,储层出现明显的白云岩化作用,晚期白云石的较高的均一温度及鞍形白云石证实了深部热液对白云岩化的贡献.幔源流体主要来自深大断裂及早期火山后期的排气、排液作用.