云南宁蒗地区喜山期斑岩带岩石化学特征和岩浆来源与成矿

宁蒗地区喜山期斑岩带为扬子西缘构造活动带喜山期构造－斑岩成矿带的重要组成部分，通过斑岩体岩石化学特征等的综合分析研究，得出了岩浆物质源于幔源，并有陆壳组分参与的壳幔混源型岩浆，斑岩体属含铜斑岩或铜斑岩。斑岩带具良好的成矿地质条件与前景。     

新疆哈勒尕提矽卡岩型铁铜矿的地质特征及找矿意义

哈勒尕提铁铜床矿位于西天山博罗科努Au、Pb、Zn、Cu、Mo异常带中,矿区发现矽卡岩型铁铜和铅锌矿体15个。铜矿、铁矿已达中型,通过深部工程控制,初步查明全区(331+332+333)类资源量:铜金属量15.2959万t,铁矿石量1321.83万t,铅金属量2341 t,锌金属量12905 t;平均品位Cu1.09%、TFe 25.55%、Pb 1.03%、Zn 5.70%。伴生组分金属量:金2.64 t、银223 t、锌7.31万t。主矿体Ⅳ、Ⅵ体在空间上分布与大理岩小残留体的形态、产状有关,同时也是化探异常浓集中心、物探低缓磁异常分布交汇的部位以及矽卡岩最为发育的地段。主矿体赋存有明显的规律性。这些成矿的地质、物化探标志性特征,对该区寻找矽卡岩型矿床有重要指导意义。     

天山东段尾亚地区白尖山超单元特征

早石炭世白尖山超单元横亘于尾亚站东西两侧，沙泉子断裂以南的狭长地带（研究区长５０余千米，宽３～６ｋｍ）。它是北部觉洛塔格早石炭世火山型被动陆缘与其南（以沙泉子断裂为界）卡瓦布拉克古陆块汇聚事件的产物。这次事件导致沿卡瓦布拉克地块北缘成线状分布的巨大岩基链的形成，即该带事实上成为一个活动陆缘弧──白尖山岩浆弧（白尖山超单元）。根据各岩石单元的接触关系，白尖山超单元由早至晚为辉长岩—石英闪长岩—花岗闪长岩—二长花岗岩—钾长花岗岩—碱长花岗岩。从沙泉子断裂向南，大体上反映出偏基性的石英闪长岩单元偏北侧分布，钾长花岗岩及碱长花岗岩单元偏南分布，表现出当时碰撞带的特性。由于晚石炭世末受到韧性剪切作用，大部分产生塑性变形，成为初糜棱岩—超糜棱岩的花岗质岩石，宏观上似具片麻状构造。无论从岩石学、岩石化学及地球化学特征方面来看，均具同源岩浆演化的特征。白尖山超单元侵入于含早石炭世动物化石的卡拉火大山组中，被二叠纪尾亚超单元组合（原尾亚岩体）侵入，测定Ｕ—Ｐｂ同位素年龄为３３８．４Ｍａ及３２５．２４Ｍａ，从而确定白尖山超单元形成时代为早石炭世。     

Characteristics of melt inclusions in skarn minerals from Fe,Cu(Au) and Au(Cu) ore deposits in the region from Daye to Jiujiang

The skarns and skarn deposits are widely distributed at home and abroad. The skarn deposits include many kinds of ores and higher ore grade. Some of them are broad in scale. Scientists of ore deposits from different countries have paid and are paying grea…     

Radiolaria‐dated Lower Permian clastic‐rock sequence in the Fukuji area of the Hida‐gaien terrane,central Japan,and its inter‐terrane correlation across Southwest Japan

The stratigraphy and radiolarian age of the Mizuyagadani Formation in the Fukuji area of the Hida‐gaien terrane, central Japan, represent those of Lower Permian clastic‐rock sequences of the Paleozoic non‐accretionary‐wedge terranes of Southwest Japan that formed in island arc–forearc/back‐arc basin settings. The Mizuyagadani Formation consists of calcareous clastic rocks, felsic tuff, tuffaceous sandstone, tuffaceous mudstone, sandstone, mudstone, conglomerate, and lenticular limestone. Two distinctive radiolarian faunas that are newly reported from the Lower Member correspond to the zonal faunas of the Pseudoalbaillella u‐forma morphotype I assemblage zone to the Pseudoalbaillella lomentaria range zone (Asselian to Sakmarian) and the Albaillella sinuata range zone (Kungurian). In spite of a previous interpretation that the Mizuyagadani Formation is of late Middle Permian age, it consists of Asselian to Kungurian tuffaceous clastic strata in its lower part and is conformably overlain by the Middle Permian Sorayama Formation. An inter‐terrane correlation of the Mizuyagadani Formation with Lower Permian tuffaceous clastic strata in the Kurosegawa terrane and the Nagato tectonic zone of Southwest Japan indicates the presence of an extensive Early Permian magmatic arc(s) that involved almost all of the Paleozoic non‐accretionary‐wedge terranes in Japan. These new biostratigraphic data provide the key to understanding the original relationships among highly disrupted Paleozoic terranes in Japan and northeast Asia.     

Metallogenic model of the copper deposit

The copper deposits in the mid-lower reaches of the Changjiang River consist mainly of porphyry, skarn and massive sulphide deposits. According to the geological background, the types of ore deposits and the mineralization, the metallogenic model of the copper deposits is discussed. It is pointed out that the ore-forming hydrothermal fluids came mainly from magmatic water and were related to the intermediate-acid intrusions, and that the formation of skarn arid massive sulphide deposits coincided with the mineralization of porphyry deposits. Project supported by Doctorate Foundation of the State Education Commission of China.     

Mechanical intrusion models and their implications for the possibility of magma-driven swarms in NW Bohemia Region

Earthquake swarms are often assumed to be caused by magmatic or fluid intrusions, where the stress changes in the vicinity of the intrusion control the position, strength and rate of seismicity. Fracture mechanical models of natural intrusions or man-made hydrofractures pose constraints on orientation, magnitude, shape and growing rate of fractures and can be used to estimate stress changes in the vicinity of the intrusions. Although the idea of intrusion-induced seismicity is widely accepted, specific comparisons of seismicity patterns with fracture models of stress changes are rarely done. The goal of the study is to review patterns of intrusion-induced earthquake swarms in comparison to the observations of the swarm in NW Bohemia in 2000. We analyse and discuss the theoretical 3D shape of intrusions under mixed mode loading and apparent buoyancy. The aspect ratio and form of the intrusion is used to constrain parameters of the fluid, the surrounding rock and stress. We conclude that the 2000 NW Bohemia swarm could have been driven by a magmatic intrusion. The intrusion was, however, inclined to the maximal principal stress and caused shear displacement additional to opening. We estimate that the density diference between magma and rock was small. The feeding reservoir was possibly much larger than the area affected from earthquakes and may be a vertical dike beneath the swarm region.     

南岭东段钨锡多金属矿床地质特征、成矿模式及找矿方向

南岭东段地区是世界著名的钨多金属矿集区。近年来中国地质调查局在该区实施钨多金属矿调查评价,找到了一批具有中大型远景的与花岗岩有关的新类型钨锡多金属矿床,特别是在复式岩体中的花岗岩型新类型钨钼多金属矿床（简称＂体中体＂式钨钼多金属矿床）和受中、上泥盆统地层控制的层控矽卡岩型钨锡多金属矿床的发现,不仅实现了南岭东段地区找矿新突破,而且对整个南岭乃至我国华南地区钨锡多金属矿找矿具有重要指导作用。本文根据近年来南岭东段地区钨锡多金属矿找矿新成果,通过该区钨锡多金属矿床地质特征的总结,建立了南岭东段地区钨锡多金属矿成矿模式,提出了南岭东段地区今后钨锡多金属矿找矿方向应重点注意与燕山期复式花岗岩有关的＂体中体＂式钨钼多金属矿床和中、上泥盆统控制的层控矽卡岩型钨锡多金属矿床的寻找。     

皖南谭山岩体的锆石定年及地质意义

皖南地区广泛分布燕山期岩浆岩,但其年代学方面的工作较为薄弱。为厘定该地区燕山期岩浆岩年代学格架,本文利用LA-ICP-MS锆石U-Pb定年方法对皖南谭山岩体的正长花岗岩进行了锆石U-Pb年代学研究,两个样品的206Pb/238U加权平均年龄分别为128．5±1．7Ma和128．3±1．5Ma,基本一致,为早白垩世岩浆活动的产物。结合本地区高精度年代学数据,皖南地区中生代岩浆岩可划分为三个峰期：第一峰期为142～139Ma;第二峰期为133～130Ma;第三峰期为128～125Ma。     

中国北方磷矿成矿特征及找矿潜力

中国北方磷矿在华北、东北以岩浆岩型磷矿和海相沉积型磷矿为主 ,在西北则以海相沉积型磷矿为主。海相沉积型磷块岩矿床主要形成于早寒武世 ,受南面和西面海水侵入影响最大、侵入距离最近的已知含磷地区可作为磷块岩矿床重点研究靶区 ;岩浆岩型磷灰石矿床所赋存的岩体类型比较多 ,但矿床规模较大 ,品位较高 ,具有较大的找矿潜力的磷灰石矿床产于超基性碱性碳酸岩杂岩体中 ,这类杂岩体在我国北方有一定的分布 ,对其做详细工作 ,可望找到规模大、品位高的磷灰石矿床