新的金矿物—珲春矿（Au2Pb）

珲春矿产于吉林东部珲春河第四系冲积砂金矿中,矿物粒度十分细小,常与自然金或阿纽依矿(AuPb_2)呈文象交生。在光学显微镜下新鲜面为灰白色,金属光泽,氧化后颜色变暗。等轴晶系,Fd3m空间群,显微硬度128～149kg/mm~2。化学成分:Au 63.38％～66.26％,Pb 31.60％～24.64％,Ag 1.76％～2.96％。矿物化学式为Au_2Pb。     

云南省墨江县金厂金矿床金银矿物成因矿物学研究

金、银系列矿物在云南墨江金厂金矿床中出现于蛇纹岩、含金石英脉.根据金银矿物的电子探针数据分析,确定了与成因产状对应的形态、赋存状态、矿物共(伴)生组合、化学成分等系列标型.从成矿早期到晚期,金矿物的结晶顺序为自然金→银金矿→自然银,金的成色有下降的趋势,银含量及矿物中微量元素总量却有明显增加的趋势.银金矿中微量元素总量...     

铬铁矿矿物包裹体的聚焦离子束-透射电镜研究

铬铁矿矿物包裹体可以记录其成岩成矿时物理化学条件（温度、压力等）、化学成分演化、熔/流体富集活动规律等关键信息.然而传统的二维分析方法无法全面获取形态微小、成分复杂的包裹体信息.通过聚焦离子束-透射电镜（FIB-TEM）联用对华北克拉通遵化豆荚状铬铁矿中矿物包裹体进行观察测试，在三维空间上发现包裹体的矿物种类丰富（硅酸盐、铂族、碳酸盐等），矿物形态复杂多变，且包裹体矿物中发育位错、部分开放晶界/相界、熔流体痕迹等显微-超显微结构.因此综合矿物种类、形态、显微结构等信息推断遵化铬铁矿具有复杂的形成条件和演化过程.      

花岗质岩石中微粒交生体的成因研究

在一些花岗质片麻岩中,经常看到分布在长石颗粒周围的细小矿物集合体——微粒交生体。电子探针分析结果表明,微粒交生体主要由钠长石、钾长石和石英组成,其标准矿物平均成分相当于An-Ab-Or体系的“低限熔点”成分。显然,微粒交生体是花岗质片麻岩经部分熔融产生的“低限熔体”的结晶产物。太古宙高级区一些晚构造钾质花岗岩的矿物,化学特征与微粒交生体类似。这意味着在塑性变形过程中产生和聚集的“低限熔体”最终可以形成大规模钾质花岗岩。     

扫描电镜下流体包裹体中子矿物的鉴定

论述了流体包裹体中子矿物的特征和鉴定方法。多相包裹体中的子矿物是由封存在矿物包裹体内的成矿流体结晶形成的固体相,它可以提供有关原始均一母流体化学成分等重要信息。研究实例说明,通过研究包裹体中子矿物可以探讨流体成矿作用、成矿方式及其矿床成矿机制等问题。     

新矿物:罗布莎矿

最近在西藏罗布莎村豆荚状铬铁矿石中发现一个由70~80种矿物组成的地幔矿物群,其中包括新矿物罗布莎矿,还有金刚石、柯石英、碳硅石、方铁矿、以及Fe-Si相矿物。所有这些矿物都是从豆荚铬铁矿石的人工大样中经选矿后得到的。罗布莎矿作为主矿物而含有自然硅和fersilicite[FeSi]的包裹体或呈交生体与自然硅共生。罗布莎矿呈不规则粒状,粒径0.1~0.2mm,由细粒聚合体组成,呈钢灰色,金属光泽,不透明。以Si为基础实验分子式为Fe0.83Si2。X-射线分析资料斜方晶系,空间群Cmca,a=9.874(14)A。,b=7.784(5)A。,c=7.829(7)A。,V=601.7(9)A。3,Z=16。罗布莎矿已为国际新矿物和矿物命名委员会批准,样品保存在中国地质博物馆。     

金刚石中的矿物包裹体

山东、辽宁金伯利岩区金刚石中的矿物包裹体是单晶相及多晶相的。大部分原生矿物包裹体为橄榄石,也有铬尖晶石、镁铝榴石、单斜辉石、斜方辉石、自然铁、针镍矿、柯石英、方解石及石墨。云母为后生包裹体矿物。橄榄石包裹体矿物富含Fo及Cr_2O_3。镁铝榴石矿物包裹体为紫红色,含Cr_2O_3,MgO及镁铬榴石分子高,形成压力为7.5GPa。单斜辉石包裹体矿物为绿色,形成温度和压力分别为:1531℃和4.5GPa。铬尖晶石包裹体矿物含Cr_2O_3及Cr/(Cr+Al)比值高,而含Al_2O_3低。柯石英的SiO_2含量为99.15％。自然铁含有少量的Co,Ni。针镍矿在金刚石中较常见。在橄榄石矿物包裹体内,见有方解石产出,其为同生矿物包裹体。     

钙稀土氟碳酸盐矿物中不同多型体间共晶格取向连生的微结构研究

利用透射电子显微镜研究钙稀土氟碳酸盐矿物中不同多型体间共晶格取向连生的微结构，发现氟碳钙铈矿（ＢＳ）及Ｂ＿２Ｓ规则混层矿物不同多型体之间存在５种新的共晶格取向连生现象，共晶格取向连生面网为（０００１）．研究表明，多型体间共晶格取向连生结构与Ｂ＿ｍＳ＿ｎ型规则混层矿物、多型体、微体双晶和矿物种间的共晶格取向连生等以衍生体的形式共存于氟碳钙柿矿自然品位之中。这种多型休间共晶格取向连生结构的形成可能与氟碳钙柿矿中ＣＯ＿３在结构层间的分布和排列有关。     

湘南两类铅锌矿床的矿物包裹体研究

本文根据矿物中原生包裹体的特征、均一温度、冷冻盐度、气相液相化学成分、pH、Eh值和电导率等的测定结果,对湘南两类铅锌矿床的成矿流体特征、成矿物理化学条件和矿床成因等重大矿床地质问题,进行了初步探索和讨论。认为它们属于同一成矿系列。     

福建省上地幔结构与岩石矿物的基本特征

综合研究了福建省上地幔的矿物、岩石、地球化学、地球物理（重、震、电）等有关资料，全面论证上地幔B′与B″层的三维空间特征、可疑地幔岩性、古代与现代地幔岩岩石类型与矿物成分。继而从地幔岩矿物组合，化学成分、微观特征、包裹体、稳定同位素等特点，来探讨第三纪上地幔的成岩环境与动力学，并指出东南沿海岩石圈上地幔减薄斜坡带及其叠生的深切断裂是燕山期双系列岩浆岩形成的深部地质背景。     

Diamond potential versus oxygen regime of carbonatites

Physicochemical conditions of graphite and diamond formation in the carbonate-rich melts were estimated. A large body of analytical data was obtained for compositions of coexisting minerals in the studied objects (Chernigovka Massif, Ukraine, and Chagatai carbonatite complex, Uzbekistan). The carbon isotopic composition of the coexisting carbonates and graphite from these carbonatites was analyzed. New thermodynamic methods were proposed to estimate the oxygen potential in graphite- and diamond-bearing carbonatites. Oxygen fugacity in the graphite-bearing carbonatites is slightly below the quartz-fayalite-magnetite buffer. It was proved that diamond is generated in the course of reduction of carbonate components arriving from plume material into the lower subcontinental lithosphere rather than owing to partial oxidation of methane fluids. As follows from the study of olivine and nominally anhydrous minerals in kimberlites, the limited role of methane in deep mantle is determined by low water activity. Methane is generated in mantle under special conditions such as extremely low oxygen fugacity (for instance, at the base of continental lithosphere) and elevated water activity. These conditions may occur during crystallization differentiation in deep-level chambers of kimberlite and proto-kimberlite magmas.     

安徽淮北朔里煤矿硬质高岭土矿石特征及自然类型划分

朔里煤矿共生硬质高岭土矿赋存在下石盒子组底部的铝土泥岩中;其主要矿物为高岭石,次要矿物软水铝石,另有少量赤铁矿、金红石、锐钛矿等铁钛矿物;化学成分以Al2O3、SiO2为主,Fe2O3＋TiO2含量超过2％则不能圈定为矿体。朔里煤矿共生硬质高岭土矿共划分四种自然类型：①灰白-浅灰色高岭土矿,②深灰-灰黑色高岭土矿,③花斑状高岭土矿,④灰色含黄铁矿或少量鲕状菱铁矿高岭土矿。     

粤东金坑Sn-Cu矿成岩成矿年代学格架与Sn-Cu共生成矿作用

金坑Sn-Cu矿床是粤东地区新发现的典型Sn-Cu共生矿床。矿区发育花岗闪长斑岩、中粗粒黑云母花岗岩和细粒花岗岩等多种侵入岩以及高基坪组火山岩,而这些岩石的年代学格架,及其与成矿过程关系还不清楚。因此,本文以粤东地区新发现的金坑铜锡矿床为研究对象,系统开展不同岩性侵入岩锆石和矿石锡石的U-Pb年龄测定,旨在浅析Sn-Cu共生成矿机制和成矿背景。结果表明,矿区中粗粒黑云母花岗岩和细粒花岗岩的锆石U-Pb年龄为145.2±1.2Ma和144.1±2.2Ma,这些年龄与该矿床的锡石U-Pb年龄(144.2±5.6Ma)在误差范围内一致,表明区内中粗粒黑云母花岗岩和细粒花岗岩与锡矿成矿关系密切。此外,获得花岗闪长斑岩U-Pb年龄为147.4±1.1Ma,且花岗闪长斑岩和高基坪组火山岩具有较高Cu含量,表明Cu可能来自于这两类岩石。结合前人研究成果,我们认为早白垩世矿区内发生了含锡中粗粒黑云母花岗岩和细粒花岗岩的侵位,其分异出富锡的还原性流体由于物理化学条件的变化析出了锡石;随着水岩反应的进行,流体萃取了围岩中的Cu、Pb、Zn等成矿元素,随着流体温度、盐度的持续下降,Cu、Pb、Zn和剩余的Sn在构造带内析出沉淀,从而造成了Sn-Cu共生成矿。     

吉林放牛沟硫铁多金属矿床原生地球化学异常特征

放牛沟矿床主要成矿元素Zn、Pb并非由地层提供,而是来自岩体深部,通过岩体接触带构造向火山—沉积岩系运移而形成矿床及原生异常的。Zn、Pb、Cu、Ag等元素正异常与Cr、Sr等元素负异常的套合产出是矿床存在的重要标志.矿体、矿组、矿床异常有明显的分带规律,分带性指数从浅部到深部呈规律性变化.根据Ag/Bi可判别前缘、尾晕,利用PbZnAgBa/CuBi可判别矿组和矿床原生异常的剥蚀程度.     

江苏金湖凹陷古近系奇碳优势和偶碳优势共存的正构烷烃

苏北盆地金湖凹陷古近纪阜宁组二段暗色泥岩及其生成的原油中,正构烷烃系列存在着偶碳优势、奇碳优势以及二者共存的3种分布型式。本文重点探讨正构烷烃奇碳优势和偶碳优势共存的形成原因。在这类暗色泥岩与原油中,正构烷烃通常低碳数部分呈nC15、nC17优势,中碳数具有nC20、nC22优势,高碳数为nC25、nC27、nC29、nC31优势;并且具有强烈的植烷优势、较高的伽玛蜡烷指数、含有一定量β胡萝卜烷和C24四环萜烷。分析认为沉积水体环境和有机质来源的变化决定了正构烷烃的分布形式,该类正构烷烃形成于湖盆水体盐度分层的沉积环境,主要来源于湖盆内藻类和湖盆外高等植物蜡。      

出芽短梗霉吸附水体中共存Cr（Ⅵ）、Cd（Ⅱ）重金属离子研究

利用出芽短梗霉进行吸附水体中Cr（Ⅵ）、Cd（Ⅱ）共存离子实验, Cr（Ⅵ）、Cd（Ⅱ）毒性浓度均为300 mg/L时,菌种生长良好。吸附性能实验结果表明：出芽短梗霉吸附水中Cr（Ⅵ）的最佳条件是pH值为3.0、时间为2 h、温度为30℃,吸附量为8.575 mg/g;吸附Cd（Ⅱ）的最佳条件是pH为5.0、时间为30 min、温度为30℃,吸附量为15.49 mg/g。     

共存矿物溶解度与硫化物金属成矿作用

金属矿床的主要金属矿物以硫化物矿物为主。硫化物与不同类型的岩石（矿物）共生时,体系溶液中硫化物的溶解度存在明显的差异,这种矿物共存溶解性质的差异导致特别的地球化学行为。本文提出了共存矿物溶解度的概念及其计算的理论和方法。并以铜陵天马山铜金硫化物矿床为例,分别计算了黄铁矿、黄铜矿和石英（砂岩环境）或方解石（碳酸盐岩环境）的共存矿物溶解度。结果表明了成矿流体流经砂岩并溶解砂岩中的原生内铁矿最终流到砂岩     

鄂尔多斯盆地东北部塔然高勒地区还原介质对砂岩型铀矿的控制

为明确鄂尔多斯盆地塔然高勒地区直罗组、延安组地层中煤、黄铁矿等还原介质与砂岩型铀矿的共存关系,选取直罗组含矿砂体及其中的黄铁矿、炭屑以及延安组煤层等为研究对象,综合利用钻孔编录、显微镜和电子探针分析等手段开展研究。结果表明,研究区铀矿体与延安组煤层、直罗组炭屑具有空间和成因上的关联,延安组煤层为铀的沉淀提供了大量的还原剂,而直罗组炭屑里的腐植酸对铀酰离子起到吸附和络合的作用;铀石是该区最主要的铀矿物类型,其与莓球状黄铁矿、蚀变黄铁矿、胶状黄铁矿、钛铁矿、白钛石伴生关系明显;有机质、黄铁矿等还原介质的含量及空间分布可以作为铀成矿的指示标志。      

Exchange of Na and K between water vapor and feldspar phases at high temperature and low vapor pressure

In order to determine whether gas (steam) containing a small amount of dissolved alkali chloride is effective in promoting base exchange of Na⁺ and K⁺ among alkali feldspars and coexisting brine or brine plus solid salt, experiments were carried out at 400–700°C and steam densities ranging down to less than 0.05. For bulk compositions rich in potassium, the low pressure results are close to previous high-pressure results in composition of the fluid and coexisting solid phase. However, when the bulk composition is more sodic, alkali feldspars are relatively richer in potassium at low pressure than at high pressure. This behaviour corresponds to enrichment of potassium in the gas phase relative to coexisting brine and precipitation of solid NaCl when the brine plus gas composition becomes moderately sodic.

The gas phase is very effective in promoting base exchange between coexisting alkali feldspars at high temperature and low water pressure. This suggests that those igneous rocks which contain coexisting alkali feldspars out of chemical equilibrium either remained very dry during the high-temperature part of their cooling history or that the pore fluid was a gas containing very little potassium relative to sodium.     

Quench temperatures of Moore County and other eucrites: residence time on eucrite parent body

We report an electron probe investigation of the eucrite Moore County. Moore County consists predominantly of four pyroxene phases and plagioclase, with minor tridymite, ilmenite, chromite, troilite, iron metal and possibly apatite. Temperatures have been computed for Moore County and other eucrites using three independent techniques for coexisting pairs of pyroxenes. These computed temperatures are all subsolidus and approach those calculated for slowly cooled terrestrial igneous and metamorphic rocks. These temperatures conflict with the conclusions of earlier workers that Moore County was catastrophically removed from its cumulate environment at high temperatures. The eucrites cooled to temperatures substantially below the solidus on their parent body.Our results are consistent with the conclusion that Moore County resided for an extended period of time on the eucrite parent body, perhaps from the time of its crystallization from a basaltic melt (～-4.5AE) until a few tens of millions of years ago. This extended residence time is consistent with the conclusion that the eucrite parent body is still intact, but raises dynamical objections to the tentative identification of the eucrite parent body as asteroid 4 Vesta.An alternative scenario involves ejection from the eucrite parent body, at times significantly older than those indicated by cosmic ray exposure ages, of meteoroids of sufficient size that their interiors were shielded from cosmic rays. These meteoroids were removed by low-probability mechanisms into Earth-crossing orbits where they were disrupted and ultimately sampled by the Earth. This proposal appears to remove the dynamical objections to the tentative identification of the eucrite parent body as Vesta.