Metallogenic model and prognosis of the Shuiyindong super-large strata-bound Carlin-type gold deposit, southwestern Guizhou Province, China

The Shuiyindong deposit is one of the largest (more than 100 tonnes of Au) and highest grade (more than 7×10-6-10×10-6), strata-bound Carlintype gold deposits in southwestern Guizhou Province, China. The deposit is controlled by both structure and favorable lithology. It is situated near the axis of the striking Huijiabao anticline and is hosted in bioclastic limestone of the Permian Longtan Formation. Gold mineralization occurred under low temperature with Th of 220℃± and is closely associated with decarbonation, silicification, sulfidation and dolomitization. The deposit has a characteristic elemental assemblage of Au-As-Hg-Tl. Studies of geochemistry and isotope compositions indicated that the ore-bearing materials and fluids of the gold deposit mainly originated from a plutonic source, and possess a mixing feature with the strata matter during transportation from mantle to crust. Fluid inclusions in vein quartz from the gold deposit are rich in volatile flux, indicating that metallogenic fluid is an overpres-sured one. The activity and geothermal state of the Earth's crust in the long period of time are favorable for the formation of overpressured fluids in a large area, and extensive structures would drive the fluids into ore-forming sys-tem and make gold deposits formed. The complexity of structural movement in the upper crust of southwestern Guizhou Province resulted in complicated gold mineralization. Through metallogenic prognosis and exploration, the proven reserves of the deposit increased by tens of tonnes of Au and the deposit has become a super-large strata-bound Carlin-type gold deposit.

Tectonogeochemical features and metallogenic prognosis in the Xiaolongtan copper mining district, Binchuan, Yunnan Province, China

The Xiaolongtan copper mining district is an important area in Dali, West Yunnan, where porphyry copper deposits occur, and copper orebodies are controlled by fault or contact zone structures between porphyry massifs and country rocks. Based on detailed field investigation and deep-going analysis, the authors systematically studied the tectonogeochemical features of this mining district, proposed the principle and foundation of metallogenic prognosis, and delineated the most potential mineralization target area.

DECOLLEMENT STRUCTURE AND METALLOGENIC PROGNOSIS FOR BURIED URANIUM DEPOSITS OF EAST HUNAN AND ITS ADJACENT AREA,CHINA

East Hunan and its adjacent area is defined as an intraplate orogenic zone with help of new theory of geology and multi-discipline research. The evolutionary stages, deep structrue, geological feature, rotation strain and metallogeny of NW-striking transfer fault zone are also discussed. NE-trending strike-slip fault zone, as a whole, entered action during Pacific movement and underwent 3 stages: the strike-slip shear, the pull-apart extension and the’ compressive thrust. The aurthors studied macro-and microscopic features of strike-slip fault and its control of uranium mineralization at Jinguangchung deposit by means of modern structure analysis, micro-submicroscopic investigation and geophysical measurement.

Geological characteristics and metallogenic prognosis of main gold deposit in Altai gold ore belt, Xinjiang

Altai polymetallic mineralization belt is famous copper-polymetallic mineralization belt in the world. There are a lot of gold deposits in the Altai ore belt in Xinjiang, China. These gold deposits belong to two genetic types: volcanogene late-stage hydrothermal type and fractured altered rock type. The authors discuss mainly the geological and mineralized features of fractured altered rock type of gold deposits in Altai gold ore belt. Base on this study, the metallogenic law is summarized and the deep metallogenic prognosis has been done in Duolanasayi and Tuokuzibayi gold deposits, and some mineralized anomalys have been discovered.

Field analysis of metallogenic information and its application

Focusing on the issue to deal with inadequate extraction of metallogenic information especially geological information,a new method of extracting metallogenic information based on field model,i.e.the field analysis method of metallogenic information,was proposed.In addition,a case study by using the method of the extraction of metallogenic information from the west Guangxi and southeast Yunnan district as an example was performed.The representation method for the field models of metallogenic information,including the metallogenic influence field model and the metallogenic distance field model,was discussed by introducing the concept of the field theory,based on the characteristic analysis of the distance gradualness and the influence superposition of metallogenic information.According to the field theory superposition principle and the spatial distance analysis method,the mathematical models for the metallogenic influence field and the metallogenic distance field of point,line and area geological bodies were derived out by using parameter equation and calculus.Based on the metallogenic background analysis,the metallogenic information field models of synsedimentary faults and manganese sedimentary basins were built.The relationship between the metallogenic information fields and the manganese mineralization distribution was also investigated by using the method of metallogenic information field analysis.The instance study indicates that the proposed method of metallogenic information field analysis is valid and useful for extracting the ore-controlling information of synsedimentary faults and manganese sedimentary basins in the study area,with which the extraction results are significant both statistically and geologically.

Late course three-dimensional conformal radiotherapy for esophageal carcinoma

Objective： The aim of our study was to evaluate the clinical results and acute side effects of late course three-dimensional conformal radiotherapy （3DCRT） for esophageal carcinoma. Methods： From January 2004 to October 2006, 70 patients with esophageal carcinoma received late course 3DCRT. Their clinical data were analyzed retrospectively. The short-term clinical results, acute side effects, local control rates and survival rates were evaluated. Results： The complete response rate was 62.9%, partial response rate was 35.7%, and the overall response rate was 98.6%. The 1-, 2-and 3-year local control rates were 77.1%, 51.4% and 45.7%, respectively. The 1-, 2-and 3-year overall survival rates were 75.7%, 54.3% and 38.6%, respectively. The median survival time was 26 months. Conclusion： The technique of late course 3DCRT is an effective treatment for esophageal carcinoma and tend to improve the overall survival rate.

Material,energy and spatial fields for metallogenic prediction:Theory and practice An example:Limu Sn polymetallic crisis mines

The Limu tin deposits located in the Nanling tin and tungsten-polymetallic ore belt are now facing resource depletion after decades of exploitation.Peripheral mineral exploration therefore has become an urgent task.Using mineral exploration around the Limu crisis mines as an example,we introduce a breakthrough method of how the three-field theory,i.e.,the material,energy and spatial fields,is applied to intensively studies areas,a history of years of mineral exploitation and complex ore-forming systems.Taking a cue from Limu regional metallogeny,we based our investigation on the metallogenic information from geology,geophysics,geochemistry and remote sensing.We conducted our study of the three-field integrated information system,associated with metallogenic prognoses from deposits,with assignments and calculations which correct and allocate synthetic metallogenic prognosis by relying on GIS.We submitted a synthetic metallogenic prognosis map of tin in Limu where we delineated three ore target areas.A breakthrough was achieved by finding about 4785 t of tin metal outside the Shiziling deposit,which has been confirmed by drilling.The successful application in Limu shows that this three-field theory is of scientific and practical importance and deserves to be extended to utilization.

胶东牟乳成矿带邓格庄金矿区深部构造特征及成矿预测

牟乳成矿带是胶东重要的金成矿带之一,为金矿集中分布区,是国内外金矿勘探和研究的热点。近年来,胶东金矿成矿规律和找矿理论不断取得新认识,尤其是热隆—伸展成矿理论的提出为深部找矿提供了理论基础。热隆—伸展成矿理论更加凸显出构造对金成矿的重要意义,深部构造研究由此显得尤为重要。广域电磁法是何继善院士团队研发的一种人工源频率域电磁勘探方法.

机器学习在地球物理勘探中铀矿资源勘查的应用研究进展

机器学习有自动性、高准确性、可扩展性等优势,适用于大数据处理和自适应任务。在地球物理勘探中运用,可大幅提高勘探效率和准确性,促进技术进步,实现地球物理向智能化解译的发展。文章首先介绍了机器学习在地球物理领域的常用先进方法,如深度学习、深度神经网络、BP神经网络、支持向量机和随机森林的基本原理和分类特点。其次介绍了放射性勘探、地球物理测井、成矿预测和联合反演的基本原理,同时对前人在机器学习应用到这4方面地球物理领域的实际应用进行综合分析,结果表明,机器学习在这4个领域中的应用均取得了显著的效果。通过机器学习技术的应用,地球物理勘探能够取得更加全面、精准和高效的成果,同时也能推动这项技术的不断进步。

黑龙江省嫩江-黑河地区水系沉积物测量地球化学特征及成矿预测

黑龙江嫩江-黑河地区分布有黑龙江省著名的多宝山矿集区,区内矿产资源丰富,以金、银、铜矿床为主,随着近年大量矿床的发现,显示该区域具备良好的找矿前景。研究区地球化学景观属于森林沼泽景观区,为更好地实现该地区的找矿突破,本次系统收集了区内1∶20万、1∶25万水系沉积物测量原始数据,对数据进行处理和分析,确定了元素的地球化学参数特征、元素的共生组合关系及其区域分布特征,共圈定单元素异常1259处,其中Au异常114处、Cu异常88处、Ag异常64处,并圈定组合异常112处。对各类元素特征进行了综合研究,并根据水系沉积物异常特征,对比异常的分布规律,同时结合典型矿床,在研究区划分了3处找矿远景区,分别为法别拉西山-长庆村北东向金银找矿远景区、多宝山地区金银铜找矿远景区和古里农场2队-大子杨山防火检查站南北向银找矿远景区,为该地区寻找金银铜等矿产资源提供依据。对远景区内的Hs-51号组合异常和Hs-38号组合异常的特征进行了解释和评价,两个组合异常内目前为止共发现了三道湾子金矿床、争光金矿床、铜山铜矿床等6处大型矿床,认为区域尚有较大成矿潜力。

阿尔金成矿带成矿规律与找矿预测

阿尔金成矿带介于塔里木盆地与柴达木盆地之间,呈北东向带状展布,长约600km。该带以北东向带状分布的太古宇-古生代变质地层为特征,同时在中-新生代断陷盆地中分布有弱至未变质的沉积岩。该区经历了多期造山运动和岩浆热事件,遭受了多期的抬升、走滑和变形作用。研究表明具有漫长地质演化历史的阿尔金成矿带发育类型较为齐全的金属、非金属和能源矿床,其中金、铜、铅、锌等矿种具有较好的成矿远景。区内金属矿床可划分为9个矿床类型,典型矿床如采石沟、大平沟、祥云金矿,拉配泉、索拉克、喀拉大湾铜矿床等。在对地、物、化、遥、区域成矿特征、控矿因素等资料进行综合研究基础上,采用GIS技术进行了矿产预测,将阿尔金成矿带划分为5个成矿亚带、10个找矿远景区和25个找矿预测区。

成矿体系的研究进展及其在成矿预测中的应用

系统地研究一定时空范围内成矿作用的各种产物,包括矿床及其示踪成矿过程的各种地质、地球化学、地球物理标志,即是成矿体系的主要研究内容,也是区域成矿学的发展趋势。中国的大陆成矿体系就是指在目前中国境内大陆地壳漫长的形成、发展过程中,随着中国大陆地壳的演变而形成的矿床成矿系列的有机整体及其在四维时空中的分布规律。通过十多年来的努力,中国地质科学院的专家们首次划分了涵盖全国国土范围的94个Ⅲ级成矿区带,对各个主要成矿区带的矿床成矿系列进行了厘定和研究,总结了区域成矿规律,建立了前寒武纪、古生代和中、新生代四个主要地质历史时期的成矿体系,总结了中国大陆阶段性演化的模式和规律;探索建立了数字化和系统化的中国成矿体系专家系统,为地质大调查和矿产资源的勘查提供理论指导和技术服务。

岩浆热液成矿理论的失败:原因和出路

流行的岩浆热液成矿理论假定含矿流体由岩浆分异作用、特别是分离结晶作用产生。由于大型、超大型矿床往往与小岩体有关,而小体积岩浆不能满足质量平衡的要求,其支持者进一步假定含矿岩体的深部存在一个大岩浆体。这种解释与矿区观察到的地质现象和理论推导结果相悖:(1)含矿斑岩中常见暗色微粒包体和大量具有较高密度的矿物,表明岩浆没有发生分离结晶作用;(2)流体的活动性远大于硅酸盐熔浆,没有证据表明岩浆分异产生的流体要在熔浆固结之后才开始活动;(3)矿区普遍见有同成矿的宽谱系岩墙群,暗示成矿期不存在大的深部岩浆房。因此,岩浆热液成矿理论遭遇的困境不仅仅是质量平衡问题,有必要重新思考岩浆相关矿床的形成机制。岩浆热液成矿理论失败的深层原因则是它将成矿作用看作是理想系统中的平衡线性过程,而成矿系统实际上是一种复杂性动力系统,成矿作用是一种非平衡、非线性过程;换句话说,在流行的岩浆热液成矿理论中,对成矿系统和成矿作用的基本属性缺乏正确的理解。在当今科学发展水平上,其失败是必然的,因而有必要构筑新的成矿理论。依据复杂性科学的基本原理,罗照华等(2007,2009)将熔浆和含矿流体看作是成矿系统中2个独立的子系统,认为它们的强相互作用及其环境约束主导了成矿系统的戏剧性变化;进而构筑了一个新的框架性模型,称为透岩浆流体成矿理论。该理论不仅可以解释比流行岩浆热液成矿理论更多的地质现象,还可以推导潜在的具体找矿标志,可能成为岩浆相关矿床成因研究的新起点。

矿产预测类型及其在矿产资源潜力评价中的运用

矿产预测类型是从成矿预测和矿产资源潜力评价的角度对矿产资源进行分类的一种方法,具有区域性但也兼顾典型矿床的一般性成矿规律,其理论基础就是成矿系列理论的矿床式。回顾了矿产预测类型概念的提出与演变过程,以阿舍勒式、大厂式和甲玛式为例探讨了作为预测工作第一步骤的重要性及划分矿产预测类型的理论依据,以大冶式铁矿为例阐述了矿产预测类型在成矿预测中的重要性和优越性。矿产预测类型基于典型矿床但又超越典型矿床的具体成矿条件因而体现出预见性,为成矿预测奠定了理论基础;同时,可以根据预测工作尺度的不同而分层次给出矿产预测类型的划分方案,可以满足分级别预测的需要;再者,矿产预测类型具有区域性特点但又不排斥一般性,既有针对性又有可操作性。分析讨论了2006年以来在全国运用矿产预测类型概念开展潜力评价工作中存在的若干问题,指出只有加强成矿规律研究才能科学地评价矿产资源的潜力。

物化探方法在青海某多金属矿区的找矿效果

根据青海多龙恰柔勘查区已有的地质信息,以含辉钼矿化、黄铜矿化的印支期、燕山期花岗岩为主要研究对象,用地球化学土壤(岩屑)测量、地球物理双频激电扫面综合圈定了3个有意义的成矿远景区,用激电测深与EH4大地电磁测深初步圈定了2个大的异常带的空间大致分布:均是走向以NNW向为主、倾向以SWW向为主、倾角较陡的大型异常带,总结了此矿区地质—地球物理—地球化学成矿模型,最后在推断出的异常部位布设钻孔并见矿。这次工作表明:因地制宜地结合各种物探方法,利用地质填图资料,综合全局考虑化探异常,扬长避短,发挥各自优势,在西部特殊景观区寻找金属矿科研与实践中具有重要意义。

中国锑矿资源潜力及成矿预测

锑矿是中国的优势矿产之一。地质大调查开展以来,尤其是西部大开发战略找矿政策实施以来,中国西部新发现了一批大中型锑矿。西藏、新疆锑矿资源优势的逐渐显现,打破了原来以湖南、广西、贵州等东部省份为主的分布格局。本文结合全国重要矿产潜力评价成果,通过广泛查阅资料,综合分析地层、构造、岩浆岩等成矿条件,在全国范围内划分了11个锑矿成矿远景区,并分析了主要成矿远景区的成矿特征和找矿潜力。同时还对其他远景区进行了简单评述,提出找矿建议。

甘肃北山公婆泉铜矿矿集区成矿构造剖析及成矿预测

甘肃肃北县公婆泉铜矿是北山成矿带一个中型斑岩铜矿床,作者运用矿田构造分析思路,综合利用重力、遥感、矿床勘查及同位素测年资料,研究了控制该矿带?矿田?矿体的不同级次构造的空间展布及形成演化,厘定出4级成矿构造:斜切弧的北西向深大断裂控制了公婆泉铜矿、勒巴泉铜矿、红柳沟铜矿、419铜矿等构成的矿集区的展布,公婆泉铜矿田?各矿区?各矿段的分布分别受控于代表岩基?岩浆柱或浅部岩浆房?热液通道的一、二、三级环形组构,各个热液通道内的矿体至少呈深浅两层矿体群出现。类似的环形构造FV1?10及外围是公婆泉铜矿田重要的找矿靶区。

成矿系统时空演化及其找矿意义

成矿系统是复杂地球巨系统的有机组成部分,其形成分布受地球系统演化的控制。地球历史演化的不同时期发育不同成矿系统,这些成矿系统既是地球系统演化的产物,也在一定程度上记录了地球系统的演化进程。我国地处古亚洲、特提斯—喜马拉雅和环太平洋成矿域的结合部位,构造演化历史十分复杂,成矿系统的叠加复合作用明显,是我国区域成矿的一个特色。成矿系统的空间分布受控于地球动力学的不均一性,以古陆边缘为例,离散型、会聚型、转换型3类构造动力环境各有其特定的成矿系统。成矿系统的形成深度、演变及现存深度取决于所在构造环境的演变。采用构造层含矿性分析法可预估一个区域中的可能矿床类型及其潜力。论文提出了隐伏矿带的概念,将找寻隐伏矿床扩展为找寻隐伏矿带,拓宽了深部找矿思路,是区域成矿学及找矿学的一个进展。

铜厂矿田陈家坝地区断裂构造地球化学特征及定位预测

陈家坝地区是铜厂矿田中重要的铜金多金属成矿区。在划分矿田构造体系和厘定成矿构造体系的基础上 ,深入阐述了铜厂矿田陈家坝地区断裂构造地球化学特征 ,认为陈家坝、陈家坝南和秦家砭、红土石构造地球化学异常集中区是进行铜金多金属矿预测的有利靶位。

西藏冈底斯铜多金属成矿带基于MRAS资源评价系统的成矿预测

西藏冈底斯成矿带是我国西部的重点成矿区带之一,特提斯演化与碰撞造山多阶段的构造演化和中生代以来广泛而强烈的花岗质岩浆侵入活动,在冈底斯成矿带形成了以岩浆作用为主的铜铁多金属矿床系列与矿床组合,主要的矿床类型有斑岩型铜钼矿、矽卡岩型铜铁多金属矿和热液型铅锌银矿。作者在区域地质条件、成矿规律与典型矿床研究的基础上,总结了斑岩型铜钼矿、矽卡岩型铜铁金属矿以及热液型铅锌银矿床的区域预测模型变量与与预测变量通过预测成果检验调整后各的权重,并利用MRAS资源评价系统对冈底斯成矿带进行了成矿预测,新圈出了一些重要的找矿远景区,如夏马日-弄如日铜金矿找矿远景区、则学-纳如松多铅锌银找矿远景区等,指出冈底斯成矿带的斑岩型和矽卡岩型矿床还具有进一步的找矿潜力。