内蒙古阿荣旗阿力格亚银金矿地质特征及找矿前景分析

内蒙古阿荣旗阿力格亚银多金属矿位于大兴安岭南坡,区内早石炭纪—晚侏罗经历多期中高温热液活动。区内断裂构造极其发育,自早元古代以来,区内经历多期构造运动形成以北东向和北西向的两组断裂。热液型及矽卡岩型金、银、铜、铁、钼等金属矿化点多分布于北东向、北西向断裂带上,或是两组断裂的交汇部,而阿力格亚银金矿床就赋存于北东向和北西向两组断裂交汇部位的次级构造断裂中。北东向断裂构造为本区的主要容矿构造。区内银、金元素地球化学异常展布特征与矿化蚀变带的空间分布相吻合,具有很好的找矿前景。     

内蒙古自治区满洲里市额日和图乌拉火山机构地质特征与找矿方向

该火山机构范围内矿化蚀变较发育,可见次生石英岩化、明矾石化、伊利石化、绢云母化、高岭土化,叶蜡石化、黄玉化、绿泥石化、萤石矿化与褐铁矿化等矿化蚀变,蚀变与该火山机构燕山晚期火山一次火山作用关系密切,其中明矾石化有进一步的工作价值.近年来通过对该火山机构开展地质、物化探工作,在其上圈出了较好1∶5万化探异常、1∶1万激电异常与地表矿化蚀变带,显示其不仅具有寻找明矾石矿产的潜力,还具有寻找铅锌多金属矿的找矿潜力.     

内蒙古嘎普特盖银铅多金属矿普查区成矿地质条件分析

嘎普特盖银铅多金属矿区属大兴安岭成矿带的组成部分,位于内蒙古二连—东乌旗成矿区北东段,构造位置位于东乌旗早华力西地槽褶皱带中段.是大兴安岭有色金属资源勘查重点地区之一.2008-2009年内蒙古自治区有色地质勘查局综合普查队通过物探(激电)面积及地质填图工作,发现激电IP1-1号和IP1.号异常和三条较好的矿化蚀变破碎带,经TC20探槽揭露南部连续刻槽取样见一宽3.80米,Zn平均品位为0.446×10-2,已达到边界品位的锌矿体.与激电异常IP1.相吻合.嘎普特盖矿区成矿条件十分有利,具有良好找矿前景.     

克什克腾旗四地银铅矿点地质特征及其成矿地质条件分析

克什克腾旗四地银铅矿点是中温热液型矿床。矿化体产出于上二叠统林西组地层构造破碎带中,矿化类型以银、铅、锌矿化为主,蚀变较强,有褐铁矿化、硅化、碳酸盐化、绿帘石化。北东向构造控制着矿化体展布,并为内生金属矿产的形成提供了运移通道、储存空间和热源等条件。     

河北省隆化县龙王庙银多金属矿地质特征及找矿前景

本文总结了龙王庙银多金属矿矿床地质特征,分析了成矿作用,认为龙王庙银多金属矿是与岩浆期后热液有关的热液脉状矿床,成矿时代推测为白垩世。银铅锌矿化严格受隐爆角砾岩体及北东向断裂构造控制,Ⅱ号蚀变带南端有望寻找隐伏的隐爆角砾岩体,其深部是寻找矿化斑岩体的有利部位,有较好的找矿前景。     

内蒙古科尔沁右翼中旗必鲁吐多金属矿地质特征分析

必鲁吐多金属矿位于内蒙古自治区科尔沁右翼中旗境内。出露地层有古生界二叠系上统林西组、侏罗系上统满克头额博组、白垩系下统梅勒图组,第四系的更新统、全新统。通过分析研究区域资料和工作成果,二叠系上统林西组板岩带受后期强烈挤压和岩浆侵入活动的影响,岩层普通绿泥石化化和硅化化,同时也形成了矿液运移的通道和贮矿空间。所以初步认为该区矿床成因为蚀变岩型多金属矿床。主要找矿标志地表寻找硅化带,在带中穿插石英脉,矿化主要为褐铁矿化,呈蜂窝状,团块状,条节状分布。与多金属矿有关的蚀变主要是绿泥石化,绿帘石化,硅化和云英岩化,蚀变越强矿化越强。方铅矿、闪锌矿呈团块状,细脉状、浸染状分布,黑钨矿与锡矿呈细脉状,主要富集于石英脉中,硅化越强,钨锡品位越高。     

陕西省车家庄地区金矿地质特征及找矿方向研究

车家庄地区位于固关-宝鸡断裂带与渭河断裂带夹持区,出露地层主要是下古生界葫芦河岩群a岩组、葫芦河岩群b岩组,区内主要断裂有F3、F4、F5三条,岩浆活动强烈,共发现3条含金蚀变带,地层、岩体、断裂构造、脉体和热液蚀变控制区内金、银等矿化。研究区内的金矿类型主要为构造蚀变岩型,重点找矿区为F3、F4断裂体系以南的葫芦河岩群a岩组的灰绿色-橘红色变砂岩地层分布区及麻窖沟地段印支期二长花岗岩体与葫芦河岩群b岩组的外接触带变质区。     

甘肃省两当县东河金矿床矿物共生组合特征

东河金矿床处于南秦岭成矿带西铅锌金多金属成矿带的东延部分,区内断裂构造发育,出露地层主要为中上志留统舟曲组和志留-泥盆系大河店组,金矿体主要产于中上志留统舟曲组粉砂质板岩中,矿体受构造破碎蚀变带控制,矿化与硅化、黄铁矿化、毒砂化关系密切。本文论述了区内金矿带的空间展布和规模及主要矿体的展布形态、品位、厚度及矿化特征,对金矿床矿物共生组合进行了探讨。     

内蒙古东乌珠穆沁旗贝格其珠浑迪锌多金属矿化区地质特征及找矿方向

二连浩特——东乌旗是我国北部重要的成矿带。矿区位于东乌珠穆沁旗乌里雅斯太镇东部约30km。区域构造位于西伯利亚板块东南部大陆边缘晚古生代陆缘增生带。工作区地层以上石炭统—下二叠统宝力高庙组(CPb1)陆相安山质火山碎屑岩和碎屑岩建造为主,岩浆岩以中三叠世黑云母钾长花岗岩(T2κγβ)为主。区内断裂构造较为发育,主要有北东向、北西向两组断裂构造,其次为一些北北东向、近东西向断裂构造。目前发现矿化体11条,矿体4条,以锌、钼为主要成矿元素。矿体主要为与中酸性岩有关的锌、钼多金属硫化矿(化)体。据矿化蚀变类型及其赋存状态,推测其成因类型应为岩浆期后中—低温热液—裂隙充填型矿床。     

内蒙古自治区丰镇市航磁异常查证成果和认识

工作区处于华北地台北缘内蒙地轴中段南缘,为我国重要的金、银多金属成矿带之一。区内基性一中酸性脉岩和中酸性岩体的大面积侵入,含矿热液在一定泄压部位的富集成矿作用较为明显,伴随的各种围岩蚀变是重要的找矿标志。金钼矿的形成除了基底老变质岩系(含金初始矿源层)之外,常与燕山期中酸性侵入岩及其他中酸性岩脉有关。银多金属矿化与燕山期开花山肉红色似斑状花岗岩及石英斑岩有密切关系。通过查证发现3条矿化蚀变带,共圈定矿体4条,矿化体11条。对该4条金矿化体进行了钻探验证,4孔累计见金矿化21.7米,最高品位0.23g/t。     

Application of the Geo-Anomaly Unit Concept in Quantitative Delineation and Assessment of Gold Ore Targets in Western Shandong Uplift Terrain,Eastern China

A number of large and giant ore deposits have been discovered within the relatively small areas of lithospheric structure anomalies, including various boundary zones of tectonic plates. The regions have become the well-known intercontinental ore-forming belts, such as the circum-Pacific gold–copper, copper–molybdenum, and tungsten–tin metallogenic belts. These belts are typical geological anomalous areas. An investigation into the hydrothermal ore deposits in different regions in the former Soviet Union illustrated that the geologic structures of ore fields of almost all major commercial deposits have distinct features compared with the neighboring areas. These areas with distinct features are defined as geo-anomalies. A geo-anomaly refers to such a geologic body or a combination of bodies that their composition, texture–structure, and genesis are significantly different from those of their surroundings. A geo-anomaly unit (GU) is an area containing distinct features that can be delineated with integrated ore-forming information using computer techniques on the basis of the geo-anomaly concept. Herein, the GU concept is illustrated by a case study of delineating the gold ore targets in the western Shandong uplift terrain, eastern China. It includes: (1) analyses of gold ore-forming factors; (2) compilation of normalized regional geochemical map and extraction of geochemical anomalies; (3) compilation of gravitational and aeromagnetic tectonic skeleton map and extraction of gravitational and aeromagnetic anomalies; (4) extraction of circular and linear anomalies from remote-sensing Landsat TM images; (5) establishment of a geo-anomaly conceptual model associated with known gold mineralization; (6) establishment of gold ore-forming favorability by computing techniques; and (7) delineation and assessment of ore-forming units. The units with high favorability are suggested as ore targets.     

Structural Analysis for Gold Mineralization Using Remote Sensing and Geochemical Techniques in a GIS Environment: Island of Lesvos,Hellas

Exploration for epithermal Au has been active lately in the Aegean Sea of the eastern Mediterranean Basin, both in the islands of the Quaternary arc and in those of the back-arc region. The purpose of this study was the structural mapping and analysis for a preliminary investigation of possible epithermal gold mineralization, using remotely sensed data and techniques, structural and field data, and geochemical information, for a specific area on the Island of Lesvos. Therefore, Landsat-TM and SPOT-Pan satellite images and the Digital Elevation Model (DEM) of the study area were processed digitally using spatial filtering techniques for the enhancement and recognition of the geologically significant lineaments, as well as algebraic operations with band ratios and Principal Component Analysis (PCA), for the identification of alteration zones. Statistical rose diagrams and a SCHMIDT projection Stereo Net were generated from the lineament maps and the collected field data (dip and strike measurements of faults, joints, and veins), respectively. The derived lineament map and the band ratio images were manipulated in a GIS environment, in order to study the relation of the tectonic pattern to both the alteration zoning and the geomorphology of the volcanic field of the study area. Target areas of high interest for possible mineralization also were specified using geochemical techniques, such as X-Ray Diffraction (XRD) analysis, trace-element, and fluid-inclusion analysis. Finally, preliminary conclusions were derived about possible mineralization, the type (high or low sulfidation), and the extent of mineralization, by combining the structural information with geochemical information.     

Three-dimensional VP and VP /VS models of the upper crust in the Friuli area (northeastern Italy)

3-D images of P velocity and P - to S -velocity ratio have been produced for the upper crust of the Friuli area (northeastern Italy) using local earthquake tomography. The data consist of 2565 P and 930 S arrival times of high quality. The best-fitting V _P and V _P / V _S 1-D models were computed before the 3-D inversion. V _P was measured on two rock samples representative of the investigated upper layers of the Friuli crust. The tomographic V _P model was used for modelling the gravity anomalies, by converting the velocity values into densities along three vertical cross-sections. The computed gravity anomalies were optimized with respect to the observed gravity anomalies. The crust investigated is characterized by sharp lateral and deep V _P and V _P / V _S anomalies that are associated with the complex geological structure. High V _P / V _S values are associated with highly fractured zones related to the main faulting pattern. The relocated seismicity is generally associated with sharp variations in the V _P / V _S anomalies. The V _P images show a high-velocity body below 6 km depth in the central part of the Friuli area, marked also by strong V _P / V _S heterogeneities, and this is interpreted as a tectonic wedge. Comparison with the distribution of earthquakes supports the hypothesis that the tectonic wedge controls most of the seismicity and can be considered to be the main seismogenic zone in the Friuli area.     

Electrical conductivity and crustal structure beneath the central Hellenides around the Gulf of Corinth (Greece) and their relationship with the seismotectonics

A deep magnetotelluric sounding (MTS) investigation in the western part of the Gulf of Corinth has revealed a complex electrical image of the crustal structure. The geotectonic structure of the Parnassos unit and the Transition zone in the central Hellenides, overthrusting the Pindos zone both towards the west and towards the south, has been clearly identified by its higher resistivity and its intrinsic anisotropy related to the N–S strike of the Hellenides range. Subsequent N–S extension of the Gulf introduced another heterogeneous anisotropy characteristic that corresponds to E–W-trending normal faults on both sides of the Gulf. The 2-D modelling of the MTS results reveals the existence of a relatively conductive layer about 4 km thick at a depth greater than 10 km in the middle crust. It corresponds to a ductile detachment zone suggested by microseismic and seismic studies ( King et al . 1985 ; Rigo et al . 1996 ; Bernard et al . 1997a ). It may be attributed to the phyllite series lying between the allochthonous Hellenic nappes and the autochthonous Plattenkalk basement. Towards the east, under the Pangalos peninsula, approaching the internal Hellenides, the detachment zone could root deeply into the lower crust.
Some strong local electrical anomalies are observed, reaching the conductive layer in the middle crust, such as that under the Mamousia fault and under the front of the overthrust of the Transition zone on the Pindos zone. Other anomalies affect only the shallower zones such as that beneath the Helike fault and in the Psaromita peninsula. These shallower anomalies provide complementary information to the study of spatial and temporal variations of the seismic anisotropy in relation to the short- and long-term tectonic activity of the Gulf ( Bouin et al . 1996 ; Gamar et al . 1999 ).     

内蒙古克旗地区银、锡多金属矿土壤地球化学测量方法及找矿效果

在内蒙古克什克腾旗——白音查干地区,运用土壤地球化学测量方法发现了诸多以银锡为主的成矿元素异常带及找矿靶区,找矿潜力较大。通过1∶5万土壤地球化学测量工作,圈出了成矿元素异常靶区3处,经过1∶1万土壤地球化学测量,进一步缩小了找矿靶区,确定了成矿有利地段12处。经过地质填图及地表工程揭露,发现银、锡、铅锌矿(化)蚀变带20余条,其中,达到边界及工业品位的矿体5条,充分说明了土壤地球化学测量方法在半干旱风成砂覆盖的草原丘陵地区具有良好的找矿效果。     

兰坪-思茅盆地与呵叻高原钾盐矿床综合对比

云南兰坪—思茅盆地与泰国-老挝呵叻高原处于同一构造带,两者在钾盐成矿及成因各方面都有着很大的相似性。通过对兰坪—思茅盆地与呵叻高原成矿地质背景、成盐时代、成盐物源和环境、沉积和地球化学特征等多方面对比分析,系统阐述了二者的异同,重点强调了存在的差异性,提出了一些今后开展工作的意见和建议。     

大连半岛地貌,新构造运动与市区安全性

辽东半岛南端的大连半岛是一个刚性断块。其上无活动性大断裂穿过,老断裂多而规模小,在地貌和新地层上无新活动表现。穿越它们的第四纪河、海阶地均平行分布,无明显的垂直或水平错位。整个半岛第四纪以来作整体断块上升。半岛上的小震稀少零星,属刚性断块地壳应力作用下的微破坏活动。位于其上的大连市是安全的,无发生破坏性大震的危险。     

中国东部大同火山群发育的构造地貌背景

大同火山群是我国东部重要独特地貌类型之一。火山群及其所在的大同盆地位于上地幔隆起带上,受中国东部最突出的构造地貌格局——NNE向雁行右旋剪切拉张断陷带控制。火山群及熔岩溢出带即明显沿着这个右旋剪切拉张破裂带以及与NW压扭性断裂交汇处发育,同时受到断裂多次活动的影响。     

新疆主要城市不同生态功能区夏季空气负离子特征

在不同天气状况下,对新疆8个主要城市5种生态功能区（林地、水体、景区、商业区和生活区）空气负离子浓度监测。结果表明：（1）不同生态功能区间空气负离子浓度差异显著（F=51.960,P= 0.000<0.001）,顺序为林地(431个/cm³)>景区(398个/cm³)=水体(398 个/cm³)>生活区(313个/cm³)>商业区(270 个/cm³);（2）各功能区空气负离子浓度日变化均表现为清晨和傍晚高于午间。单因素方差分析表明林地、水体和景区午间空气负离子浓度与清晨和傍晚的差异不显著,生活区和商业区差异显著;（3）景区和林地[WTBX]CI[WTBZ]值（0.50和0.49）处于中等清洁范围,属C级;水体和生活区[WTBX]CI[WTBZ]值（0.45和0.29）处于容许范围,属D级;商业区CI值（0.24）在临界值以下,属E级;（4）从林地、水体、景区、生活区到商业区,D级和E级天气所占比例不断增加,B级和C级天气不断减少,说明空气质量逐步下降;（5）不同天气状况下各功能区空气负离子均表现为雨天>晴天>阴天>沙尘（浮尘）。     

南极布兰斯菲尔德海峡海磁异常和深部地质

文章导出了南半球ΔＴ表达式，测区约位于６３°Ｓ，故异常以正值为主，负异常在其南侧。以化极、匹配滤波等方法处理数据得深浅源异常。深源异常自北向南以正负相间的三个条带状异常分别对应着南设得兰群岛、布兰斯菲尔德海峡和南极半岛，浅源异常则对应着海峡南北缘的两条断裂。深部异常认为是磁性基底隆拗所致，因太平洋板块对南设得兰群岛的俯冲，那里深部基性成分多，故北部的深浅源异常幅值皆比南部的高。据浅源异常还识别出了与海峡延伸方向垂直的断裂，结合地貌、岩浆岩年龄及地震波速分布，进一步认为南极半岛地区可能发生过西向漂移。