安徽贵池铜山矽卡岩型铜矿床蚀变矿化分带特征及其成因

铜山矽卡岩型铜矿床产于长江中下游铁铜成矿带中的安庆—贵池矿集区。研究区矽卡岩化与矿化发生于碳酸盐岩地层与花岗闪长斑岩间的接触带中,蚀变及矿化具有水平与垂向分带特征。水平方向上,靠近岩体的矽卡岩中石榴子石含量较高,远离岩体的矽卡岩中透辉石含量较高;靠近大理岩带发育钙铁辉石矽卡岩,远离大理岩带的灰岩硅化较强。垂向上,从上到下依次为角岩带、钙质矽卡岩带和镁质矽卡岩带。矿物成分研究表明,靠近岩体处氧化性较强,石榴子石的钙铁榴石端员含量高;铜多富集于含石英脉的岩体、距岩体略远的矽卡岩、角岩或大理岩中,而锌多富集于硅化灰岩及远离岩体的矽卡岩中。研究表明,该矿床中蚀变矿化经历了进变期和退变期,包括接触热变质阶段、进化交代阶段和早退化蚀变阶段、晚退化蚀变阶段。其中,大规模的黄铜矿化主要发生于早退化蚀变阶段,且在岩浆演化晚期进一步富集于斑岩石英脉中。     

延边地区白石砬子白钨矿矿床地质特征及成因探讨

白石砬子白钨矿床产于下古生界青龙村群大理岩与华力西晚期黑云母斜长花岗岩接触带内;矿体呈脉状、扁豆体产出,受北东向断裂构造和接触带构造控制明显;赋矿岩石以石榴石矽卡岩为主,矿石中金属矿物以白钨矿为主,其次为黄铜矿、磁黄铁矿、黄铁矿等,非金属矿物有钙铝石榴石、钙铁辉石、透辉石、绿帘石、方解石、石英。矿床特征及与国内典型矿床对比分析表明,白石砬子矿床的成因类型属接触交代型白钨矿矿床。青龙村群大理岩、海西华力西晚期花岗岩体、北东向断裂和接触带构造对该矿床形成具有重要控制作用,矿区及外围具有较大的成矿潜力和找矿远景。     

对柿竹园矽卡岩成因及其成矿作用的新认识

本文将报导柿竹园Ｗ，Ｓｎ，Ｍｏ，Ｂｉ矿床中矽卡岩矿物－石榴子石和辉石成分和石榴子石中熔融包裹体研究结果，对不同中段的１６块矽卡岩样品（９４％的标本采自第Ⅲ矿带）中的石榴子石和辉石进行了电子探针分析，共获得２３０个测点的数据，此外，还对上述中段大部分样品里的石榴子石和辉石进行了从边部到核心成分测定，共获得１３个样品的９７个测点数据，研究结果表明，绝大多数石榴子石属于含Ａｌｍ＋Ｓｐｓ＋Ｐｙｒ〈１３％（     

湖南七里坪－半边街镁质矽卡岩硼矿床微量元素地球化学

湖南七里坪－半边街接触交代型硼矿，矿体产于中石炭统壶天群白云岩与燕山期花岗岩接触带的矽卡岩中，产状受岩体顶板形态的控制，多为似层状、透镜状、囊状等。一般离岩体较远的部位硼矿石的品位较富，但靠近岩体的部位矿体较厚大。据微量元素相关系数聚类谱系图分析，Ｂ元素在岩体中呈分散状态，在高温热液中易于聚集，在矽卡岩中富集成矿，在蚀变的白云岩中有轻微的富集。     

我国一些重要夕卡岩Pb-Zn多金属矿床的交代分带

在我国一些重要夕卡岩Ｐｂ－Ｚｎ多金属矿床中，交代矿化分带十分明显，主要表现为围绕侵入体接触带或热源中心向碳酸盐围岩方向１，呈现有规律的带状分布１。根据有关岩浆岩和矿化组合的不同，可大致划分为三个匀代分带序列，总的分带序列是：Ｆｅ（ＭＯ）－Ｆｅ－Ｓｎ－Ｓｎ（Ｗ）－Ｃｕ－Ｃｕ－Ｚｎ－Ｚｎ，Ｐｂ（Ａｇ）。     

铜官山铜矿床矽卡岩矿物中流体包裹体及子矿物的扫描电镜研究

通过对安徽铜官山铜矿矽卡岩矿物中的流体包裹体岩相学、包裹体显微测温分析及子矿物的扫描电镜／能谱分析(SEM／EDS)和激光拉曼探针分析(LRM)，发现石榴石、透辉石中的包裹体为流体包裹体，包裹体的均一温度(575～885℃)、盐度[w(NaCleq)13．4％～44．9％]均较高，流体包裹体中的子矿物有黄铜矿、闪锌矿、方解石、菱铁矿、钾石盐和石盐，以钾石盐最为普遍，表明流体高度富钾，具岩浆热液的典型特征。富钾流体也与该区广泛出露的燕山期高钾富碱岩体吻合。     

Geochemical Behaviors of REE and Other Trace Elements during the Formation of Strata-bound Skarns and Related Deposits: A Case Study of the Dongguashan Cu (Au) Deposit, Anhui Province, China

REE and other trace elements in the altered marbles, massive skarns and ores, as well as garnet and quartz were determined in order to examine the behaviors of trace elements during hydrothermal alteration. It is demonstrated that the high-field-strength (HFS) elements Zr, Hf, Th and Nb were immobile while other trace elements were mobile during the formation of skarns and related deposits. REE and ore-forming elements such as Cu and Ag in hydrothermally-altered marbles and skarns were provided primarily by hydrothermal fluids. In the direction transverse of the strata, the more deeply the marbles were altered, the higher the total REE abundance and the larger the negative Eu anomalies would be. The chondrite-normalized REE patterns of skarns are similar to those of the marbles, but the former are distinguished by much higher REE contents and more remarkable negative Eu anomalies. Those patterns were apparently not inherited from the marble protolith, but were controlled by garnets, which were determine     

羊拉地区含矿夕卡岩流体包裹体特征及其成因意义带

羊拉铜矿化集中区共有４个夕卡岩体,按成因分为喷流－沉积和接触交代夕卡岩两大类,前者呈层状,是铜的主要赋矿围岩。层状夕卡岩中包裹体以类型多、组分复杂、均一温度（１００～６２０℃,一般大于３００℃）和盐度（８．３％～５５．０％ＮａＣｌ,一般≥２０％ＮａＣｌ）高且变化范围大、密度高（一般大于１．００ｇ／ｃｍ３）、捕获压力低（１０～２５ＭＰａ）为特征;交代夕卡岩则以包裹体类型简单、组分单一、均一温度（一般小于２５０℃）和盐度中—低（９．０％～２０．０％ＮａＣｌ）、密度低（一般小于１．００ｇ／ｃｍ３）且变化范围大、捕获压力高（１５０ＭＰａ）为特征。这些包裹体特征反映了两类夕卡岩的流体来源和演化机制是不同的,其中层状夕卡岩之流体为深部源与海水源的二元混合特征;交代夕卡岩为岩浆（体）源等组分自然冷却演化趋势。     

The Discovery of Magnesioferrite from Au (Fe, Cu) Magnesian Skarn Deposits and Study of the Magnesioferrite-Magnesiomagnetite Series

Magnesioferrite, a rare metasomatic mineral, was discovered for the first time in China from the Qinlou Au (Fe, Cu) magnesian skarn deposit, Sanpu, Huaibei, Auhui Province, and the Mulonggou Fe (Mo, Cu) magnesian skarn deposit, Luonan County, Shaanxi Province. In this paper, the geological setting, mineral associations, chemical composition, some physical properties, X-ray powder diffraction data and infrared spectroscopy of magnesioferrite and magnesiomagnetite are discussed. Magnesioferrite contains 17.66%-13.48% of MgO. Its main associated minerals are clinohumite, chondrodite, serpentine,, calcite and magnesiomagnetite. The density of magnesioferrite is 4.537-4.720, reflectances in percent are: 17.8-18.1, hardness is 838-900 kg/mm2, and the cell parameter a0 = 8.371-8.379 A. A systematic study of the magnesioferrite-magnesiomagnetite-magnetite series suggests that along with the increase of magnesioferrite molecules in the mineral, the density, reflectances and cell parameters decrease corresponding     

山东海阳土堆金矿床地质特征

山东海阳县土堆金矿床位于郭城断裂带以东,赋存在荆山群野头组大理岩与燕山期闪长玢岩接触带内侧。金矿体受ＮＥ向次级构造裂隙控制,多呈脉状、似层状产出。矿石矿物成分复杂,具夕卡岩化、黄铁矿化、硅化及碳酸盐化等蚀变,成矿过程曾发生接触交代作用。该矿床具有含金夕卡岩型矿床的一般特征,在胶东地区属于一种新的金矿类型。