Characteristics of magmatic rocks and tectonic setting of Mazhuangshan area, East Tianshan, China

The Mazhuangshan area lies in northeast to Aqikekuduke,where are distributed in-termediate-acid rocks,which were formed in the Middle-Late Carboniferous epoch.The magmatic rocks are peraluminous and belong to calcareous series.All values of ACNK(1.03-2.12),ANK(1.67-2.93),SI(4.1-33),δ(0.71-4.82),La/∑REE(0.09-0.26) ∑LREE/∑HREE(1.76-11.01),(La/Sm)N(1.60-6.35),(Sm/Nd)N(0.33-0.58),(La/Yb)N(4.7-12.1),LaN/Lux(5.9-11.8),(Ce/Yb)N(3.14-6.64),δEu(0.38-1.06),RbN/SrN(41-120)and Sr(0.02-0.2)demonstrate they vary with D_I(45-90).S-B diagram also shows that the lithophile elements are abundant in acidic magmatic rocks,Moreover,it is concluded that the primitive magma originated from a subduction zone at the continental edge,and underwent fractional crystallization and contamination,then generated the magmatic rocks,The multi-cation index(R:3055-3993,R2:286-438) shows that the primitive magma originated from the mantle,All these conclusions are beneficial for exploring gold deposits in the area.     

成矿体系研究和应用新进展

在探索成矿规律和找矿实践中,从岩浆热液成矿、成矿构造体系和成矿系列等研究,提出了"成矿体系"的概念,分别赋予不同定义并用于找矿实践,取得了一定成果。但对成矿体系源于何时、出于何处、原意为何等问题却较少追究,也存在一些争议。文章就成矿体系的概念,从岩浆热液成矿到岩浆-热液-成矿体系、成矿构造体系到成矿体系和成矿系列构筑成矿体系的由来,综合概括,提出成矿体系的新定义,揭示其新特点,并对断裂网络+成矿体系、成矿结构体系和成矿系列缺位的思路和方法进行成矿预测、资源潜力评价和矿产勘查取得的新成果及新进展,作简要论述,以供借鉴。     

Study on the origin of the Hongshan brecciated copper deposit in Huichang County,Jiangxi Province,China

The Hongshan copper deposit is a typical cryptoexplosive breccia-type deposit, which occurs in a metamorphic rock series of the Mesoproterozoic Taoxiyuan Formation. Orebodies are distributed inside and outside porphyry-cryptoexplosive breccia pipes. The isotope geochemistry of the deposit is consistent with the origin of porphyry breccia: the δ18OH2O values ranging from 1.2‰ to 6.1‰ and the δ34S values varying from 0 to 2.5‰. 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb ratios of pyrite, which coexists with ore minerals, indicate it was derived from the orogenic belt. Thermodynamic analysis indicates that the main metals were deposited largely as a result of the decreasing of proton concentrations associated with H2S and CO2 exsolution during explosion and temperature dropping. Based on K-Ar dating of quartz coexisting with ore minerals, the age of mineralization was estimated to be 97.1–98.8 Ma, which suggests that mineralization occurred between the Early and Late Cretaceous. According to the relevant information obtained, a diagenetic and metallogenic pattern in the area has been presented in this paper.     

浙江建德铜矿床地质特征及其成因研究的新进展

通过对建德铜矿床调查研究,总结矿床成矿条件,分析控矿因素,探索矿体分布规律,确定岩浆热液成因后,提出矿液运移理论,首次运用计算机进行数学物理模拟和深部成矿预测,已均被证实,表明所采用理论、方法的合理性和正确性。因矿区发现少量火山岩和硅质岩等而提出海底火山热液沉积成因,经近年矿区地质特征、成矿年龄和流体包裹体等详细研究和开采勘查,认为该矿床为岩浆热液成因,并据此在该矿床外围找到类似的高岭铜矿床。随着矿床研究的深入,在矿床地质特征、成矿时代、成矿流体和成矿物质来源等取得了新进展,矿床成因和成矿机制也因此得到进一步验证。     

澳大利亚凹凸棒石（坡缕缟石）粘土矿床的分布、类型、特征及成因

本文旨在介绍凹凸棒石（坡缕缟石）粘土矿床在澳大利亚的分布、矿床类型、典型矿床特征及成因,以求国人了解和借鉴。     

锦屏水电站及外围地区现今构造应力场的有限元单元法模拟

现今构造应力场是评价工程地区稳定性最重要的因素之一,特别对大水电工程建设具有重要意义,为此,以锦屏水电站及其外围地区为区,在野外地质调查及室内综合分析基础上,并考虑到川西－滇北地区构造应力场对锦屏水电站及其外围地区的影响。     

江西会昌红山斑岩—隐爆角砾岩型铜矿床地质、地球化学及成因

红山铜矿床位于贛南会昌城南约30余千米的中村乡,探明储量为中型,近年经作者系统研究认为,有大型前景。红山铜矿床位于武夷山南段西坡、古生代华夏与南华陆块拼接带、中新生代东南沿海活动大陆边缘内侧、前陆冲断推覆带隆起一侧。红山斑岩-隐爆角砾岩型铜矿床赋存中元古界中村群变质岩系中。矿体分布于斑岩-隐爆角砾岩筒内外,矿床由斑岩     

新疆康古尔—黄山对接碰撞带的存在、成矿模式及成矿预测

据地层及其时代，岩相古地理，基性－眼基性岩及蛇绿岩套，花岗岩类，古生物地理区系，古地磁，地球物理，遥感影像及韧性变形变质带等系统分析研究，表明康古尔塔格－黄山深断裂带为晚古生代双向俯冲对接碰撞带。其南为塔里木板块，早古生代为库都克奇克－沙泉子俯冲带；泥盆纪北移至康古尔塔格－黄山一带，经泥盆－石炭纪拉张，双向俯冲、对接碰撞，二叠纪固结－裂解演化，两者间为觉罗塔格岛弧增生带，其北为哈萨克斯坦－准噶尔板块南缘大南湖岛弧带，有基性－超基性岩、火山岩和中酸性斑（玢）岩及铜镍、金和铜钼矿分布，中酸性斑（玢）岩及铜钼矿呈对称分布，进而建立区域构造－造浆－成矿模式，进行战略性和战术性成矿预测，千万吨资源量的赤湖－土屋斑岩型Cu,Mo(Ag)矿的发现，验证了这种模式和预测的正确性，对地质构造研究及找矿有重要意义。     

江西会昌红山斑岩-隐爆角砾岩型铜矿床特征、成矿物质来源及成矿过程动力学

该矿区地层为中元古界中村群变质岩系;有北东、北北东、北北西和北东东向断裂;燕山晚期花岗斑岩、花岗闪长斑岩,伴随其侵入产生隐爆角砾岩筒、蚀变和矿化。有8个矿体,平均Cu品位为0.636%;主要有辉铜矿、斑铜矿和黄铜矿,主元素为Cu,伴生Pb、Zn、Ag、Au、Mo和S。围岩蚀变以硅化、绢云母化、钾长石化和黄铁矿化为主,具分带性。热液成矿分为3期,主成矿期为97×l0^{6<、sup>～98×l06<、sup> a。矿质源自下地壳;介质以岩浆水为主,与变质水、地层水和雨水组成混合水;热源由斑岩岩浆提供。在构造动力作用下,地壳圈层剪切致热,地壳部分熔融,形成岩浆房,上侵成岩浆室,随其结晶分异,在岩体顶部聚集挥发组分和金属物质,强大机械能引起裂隙、隐爆,温压下降,气体变为液相,矿质淀积、成矿,经历面型、线型和叠加矿化,形成斑岩-隐爆角砾岩型铜矿床和“一体五型”成矿体系。}