霍什布拉克铅锌矿床成因研究

矿体赋存在上泥盆统坦盖塔尔组上段碎屑岩向碳酸盐岩过渡部位，具有双层结构。矿石组构具有明显的热水沉积成因特征，研究表明：矿床成矿物质主要来源于深部寒武-奥陶系的基底地层。矿床系下渗的海水和大气水混合淬取了基底丰富的成矿物质形成上升热卤水在海盆中喷流沉积而成。     

澳大利亚世纪铅锌矿床地质特征和成矿模式

澳大利亚世纪(Century)铅锌矿床赋存于中元古代劳恩希尔组页岩和粉砂岩中。矿化主要为细粒闪锌矿,其次为方铅矿和黄铁矿。大部分硫化物(80%~90%)在黑色页岩单元中以易碎的交代层状出现,被富菱铁矿粉砂岩层隔开。矿化具有2个大尺度的变化趋势,在白蚁圈断层由北东至南西,Zn品位显著降低,由南东至北西,Zn品位略有降低。层状闪锌矿主要有2种结构,多孔闪锌矿的焦沥青含量较高,无孔闪锌矿焦沥青含量较低。S同位素研究显示,整个成矿流体系统是一个封闭的储层,重S在变形与成矿事件中进一步富集。世纪矿床由变形作用驱使流体迁移到异常高压(压实作用下的)页岩层位时,页岩容矿的矿化作用形成。较热的富含金属的流体和较深盆地的卤水,使得有机质迅速成熟,最终导致硫酸盐的还原和贱金属的沉淀。     

Pan-African high pressure granulites from SE-Kenya: Petrological and geothermobarometric evidence for a polycyclic evolution in the Mozambique belt

Two different Pan-African tectono-metamorphic events are recognised in the Taita Hill Tsavo East National Park/Galana river area, SE-Kenya (Mozambique belt) based on petrographic and geothermobarometric evidence. Structurally, this area can be subdivided into four units: (1) the easternmost part of the basement along the Galana river is characterized by subhorizontal slightly to the west and east dipping foliation planes. Migmatic paragneisses with intercalated marbles, calcsilicates and metapelites and bands of amphibolites are the dominant rock type. (2) The western part of the Galana river within the Tsavo East National Park is a ca. 25 km wide shear zone with subvertical foliation planes. The eastern part shows similar rocks as observed in unit 1, while towards west, metasedimentary units become rare and the main rock types are tonalitic gneisses with intercalated amphibolites. (3) A 10 km wide zone (Sagala Hills zone) between the strike slip zone (unit 2) and the Taita Hills (unit 4) is developed. This zone is characterized by elongated and folded felsic migmatic amphibole and garnet bearing orthogneiss bodies with intercalated bands of mafic rocks. (4) The Taita Hills are a slightly to the N dipping nappe stack. The main rock type in the Taita Hills are amphibole–biotite–plagioclase–quartz ± garnet ± clinopyroxene ± scapolite bearing migmatic gneisses with mafic bands. In the southern part, metapelites, marbles and some amphibolites are common.Although the geological structures are different in units 1 and 2, the calculated PT conditions are similar with peak PT of 760–820 °C and 7.5–9.5 kbar. Temperatures in unit 3 (Sagalla Hills zone) and unit 4 (Taita Hills) are slightly higher ca. 760–840 °C, but pressure is significantly higher, ranging from 10 to 12 kbar. Sillimanite growth around kyanite, garnet zonation pattern, mineral reaction textures, and PT calculations constrain a “clock-wise” PT-path with near isobaric cooling following the peak of metamorphism. The different PT conditions, tectonic setting, and a different age of metamorphism are evidence that units 1 and 2 (Galana river) belong to a different tectono-metamorphic event than unit 3 (Sagala Hills zone) and 4 (Taita Hills). The major shear zone (unit 2) marks a tectonic suture dividing the two different tectono-metamorphic domains. It is also likely that it played an important role during exhumation of the granulite facies rocks from units 3 and 4.     

Tectonic Evolution of the Himalayan Collision Belt

This paper discusses the tectonic divisions of the Himalayan collision belt anddeals with the tectonic evolution of the collision belt in the context of crustal accretion in thefront of the collision belt, deep diapirism and thermal-uplift extension and deep material flow-ing of the lithosphere-backflowing. Finally it proposes a model of the tectonic evolution-progressive intracontinental deformation model-of the Himalayan belt.     

对秦岭造山带几个重大问题的认识

详细讨论了秦岭一大别造山带的几个重大问题，对它的发展阶段进行了新的划分，对其形成发表了新的观点：认为秦岭造山带、华北板块、扬子板块是中生代以来，在抽拉－逆冲岩片构造体制作用下形成的。对秦岭一大别造山带的表层构造特征以及它和深层构造的关系、花岗岩的成因类型、断层与界面的区分及成矿作用等都提出了和以往不同的认识。     

新疆额尔齐斯金矿带构造控矿规律研究

额尔齐斯金矿带位于新疆阿尔泰南缘。地质研究表明,发生于晚石炭世—早二叠世的金成矿作用在整个额尔齐斯金矿带中广泛发育,明显受额尔齐斯韧性剪切带及其次级断裂的控制。通过对额尔齐斯构造带及其中发育的21个金矿床(点)尤其是多拉纳萨依、托库孜巴依、萨尔布拉克、科克萨依和马热勒铁等金矿床控矿构造的研究,作者提出如下新认识:额尔齐斯韧性剪切带总体上具有向东收敛、向西散开的基本形式,控矿构造具有向东单一(仅为韧性剪切构造)、向西复杂(脆韧性构造叠加于韧性构造和中酸性岩体上)的特点,由此控制的金成矿作用具有“东浅西深、东弱西强”等6条基本规律。在此基础上,结合EH4深部地球物理测量结果,指出额尔齐斯金矿带西部哈巴河地区和中部富蕴地区是形成大型金矿床的有利地区。     

西秦岭甘肃夏河—合作地区与中酸性侵入岩有关的金铜多金属成矿系统及找矿预测

甘肃夏河—合作地区岩浆岩与矿产分布具有分带性：夏河-合作断裂以北侵入岩规模较大,以岩基、岩株为主,发育Cu、Au、W、Mo、Pb、Zn等以中高温元素为主的矿化,受岩体边缘接触带及断裂双重控制;夏河-合作断裂以南侵入岩规模较小,多以小岩株、脉岩出现,发育Au、Hg、Sb等中低温矿化,受断裂破碎带控制。地球化学组成显示,该区侵入岩具有镁闪长岩、TTG岩套的双重特点,为"热壳"+"热幔"的壳幔结构,成矿条件极为有利。硫、氢、氧稳定同位素特征指示,成矿物质主要来自地幔岩浆析出的热液,后期有大气降水的参与。夏河—合作地区为与中酸性侵入岩有关的金铜等多金属矿成矿系统,在夏河-合作断裂以南,剥蚀较浅,可寻找远成低温热液型金、锑矿等,在其深部还应注意寻找斑岩型或矽卡岩型铜金矿床。而在剥蚀程度较高的北带,应以斑岩型和矽卡岩型矿床为主。     

辽西北票、义县地区髫髻山旋回火山岩的地球化学特征

北票、义县地区髫髻山组可分为3个岩性段.髫髻山火山旋回划分为2个亚旋回.髫髻山旋回火山岩属于高钾钙碱性岩系,SiO2=53.67%~75%,Al2O3=13.15%~19.16%,K2O+Na2O=5.17%,里特曼指数δ=1.46~6.83,平均值为3.06;富碱贫镁,Na2O>K2O.Cr、Ni含量低,亲石元素Rb、Sr、Ba等含量高.稀土元素总量较高,富轻稀土,稀土分布模式呈右倾型,稀土元素分馏明显,总体为负铕异常,弱铈异常.成因研究表明,髫髻山旋回火山作用是在与挤压作用相关的大陆边缘活动带构造环境下,受壳断裂控制形成的,具有造山带火山岩特征.火山岩的成岩作用以部分熔融为主,其源区物质为LREE相对富集的下部玄武质地壳.     

丝绸之路经济带甘肃黄金段找矿勘查新进展

丝绸之路经济带已成为国家战略,赋于了上合组织新的内涵,也给地质工作者提出了新的要求。甘肃是古丝绸之路的锁匙之地,是丝绸之路经济带上的“黄金路段”。2014年甘肃省提出利用拥有古丝绸之路贯穿境内1600 km的战略通道优势,打造丝绸之路经济带的黄金段,使其成为向西开放的战略平台、经贸物流的区域中心、产业合作的示范基地、人才交流的桥梁纽带。本文就甘肃省矿产资源优势、找矿勘查新进展及向西走出去提出建议。