The Laochang polymetallic deposit is the only large deposit in the Changning-Menglian Junction Zone. The deposit features by deep porphyry-skarn Mo-(Cu) and shallow vein Pb-Zn-(Ag) mineralization. Researches on the deposit have yielded extensive data, however, details about the initial evolution from magma to ore-forming fluid remain unclear. This study centers on the in-situ analysis of biotite from the porphyry, as well as phlogopite and titanite from the A vein, leading to the following insights: (1) The biotite geothermobarometer suggests the porphyry intruded in a moderate depth (2.57-4.27 km), with average parameters as P = 93 MPa, T = 697 degrees C, and logfO2 f O 2 =-16.78. (2) The A vein in the deposit can be further subdivided into A1 K-feldspar vein and A2 quartz vein. The phlogopite in the A1 vein formed at P = 98 MPa, T = 681 degrees C, and logfO2 f O 2 =-17.29. The pressure of the A1 vein is slightly higher than the static pressure of wall rock, attributed to pressure increment from the initial exsolved fluid. Conversely, the temperature and oxygen fugacity experience a slight decrease, due to buffering of the adjacent tuff. (3) The in-situ LA-ICP-MS U-Pb dating of the titanite in the A1 vein yields 44.4 +/- 1.5 Ma (MSWD = 1.8, n = 48), comparable to the emplacement age of the porphyry (44.6-44.4 Ma). It is slightly older than the main mineralization age (43.78 Ma), further delineated the initial evolution sequence from magma to ore-forming fluid. Our research suggests that the in-situ analysis of titanite is crucial for preciously tracking the magma-fluid system, as titanite records both time and temperature information.

To benefit agricultural planning and guarantee food safety in Dushan County,totally 120 crop 120 rhizosphere soil samples,10 soil profile and 10 ore parent rock samples were collected to examine for heavy metal(loid)s(As,Cd,Cr,Cu,Hg,Ni,Pb,and Zn),as well as organic matter concentrations and pH value.We evaluated the heavy metal(loid)pollution using the single-factor index method,geo-accumulation index method,crop enrichment factor,and health risk assessment method.Our findings indicate that:(1)In Dushan County,the highest concentrations of As,Cu,Hg,and Zn were found in tomato rhizosphere soils,averaging 21.38,22.18,0.42,and 110.39 mg/kg respectively.The highest Cd,Cr,Ni,and Pb concentrations were found in corn rhizosphere soil with mean values of 1.05,111.12,29.02,and 34.50 mg/kg respectively.The pH of rhizosphere soils ranged from 3.58 to 8.24,with 87.5％of samples showing a pH value below 6.5,indicating overall a slight acidity.Single-factor index analysis revealed"slight to moderate pollution"levels of Cd in rhizosphere soils,as well as"slight to moderate pollution"of Cd in soils and crops.Geo-accumulation index results showed that human activities influenced As,Cd,Hg,and Zn levels in crop rhizosphere soils.(2)Among the 120 crops,rice and corn exhibited the highest exceedances of Cd standards(33.33％for rice,13.33％for corn),followed by Pb(3.33％for rice),and Cr(30.00％).No exceedances were found in grapes,tea,and tomatoes.Crop enrichment factors indicated that Cd enrichment was several times to hundreds of times higher than that of As,Cr,and Pb,highlighting strong Cd and Pb uptake capacities in crops,especially for Cd.Health risk assessment values for As,Cd,Cr,Hg,and Pb in crops for both adults and children were all below 1,indicating no health risks associated with heavy metal(loid)uptake by crops.

The Longwan uranium deposit in Sansui County,Guizhou Province,is a large-scale uranium deposit discovered by exploration in recent years.Its orebodies occurred in layered and quasi-layered forms in the black rock series of the Sinian-Cambrian Laobao Formation.Previous studies on the geology and geochemistry of the deposit were conducted.However,the occurrence status of uranium,the source of ore-forming materials,and the metallogenic environment of the deposit are still unclear.In this study,the Laopeng profile located in the southern part of the Longwan deposit has been selected as the research object for studying its mineralogy and whole-rock elemental geochemistry.The results reveal that uranium occurred mainly in the form of independent uranium minerals such as pitchblende and brannerite in edges,fissures and holes of apatite grains,or partly in the form of isomorphism in the crystal lattice of apatite.The results of whole-rock geochemical analyses reveal that samples from the Laobao Formation have Y/Ho values ranging from 16.3 to 63.2(with an average of 40.3),Zr/Hf values ranging from 33.6 to 79.3(with an average of 42.3),which are similar to those of the upper crust.These samples have relatively flat REE distribution patterns,with no or weak Eu positive anomalies(δEu values ranging from 0.27 to 1.19,at an average of 0.82).The siliceous rocks have Ge/Si values ranging from 1.23× 10-6 to 0.15× 10-6(with an average of 0.47× 10-6),which are similar to those of the modem seawater,suggesting that the lithogenous and ore-forming materials of the Longwan deposit were mainly sourced from the continental weathering clastic materials which were limitedly affected by the seafloor hydrothermal fluid.The samples from the Laobao Formation have V/(V+Ni)values ranging from 0.43 to 0.98(with an average of 0.80),and Ni/Co values ranging from 1.80 to 58.0(with an average of 12.7),with significantly negative Ce anomalies(δCe values ranging from 0.31 to 0.81,at an average of 0.60)on their REE distribution patterns,suggesting that the Longwan uranium deposit was formed in a reduced sedimentary environment.Our comprehensive research shows that the Longwan black rock series uranium deposit was formed under the reduced condition by U-bearing clastic materials sourced from the continental weathering in the eastern Guizhou in the period from Late Neoproterozoic to early Late Paleozoic.

为了探究黔北凤冈地区碳酸盐型铀矿化的物质来源,文章对黔北凤冈地区的沙坪铀矿点高品位矿石中的方解石开展LA-ICP-MS微量元素研究.研究表明:沙坪铀矿点受近南北向杨家堡断裂控制,赋存于娄山关组和桐梓组白云岩中,成矿过程分为方解石(Cal-1)-石英-沥青铀矿-黄铁矿(Py-1)阶段和方解石(Cal-2)-石英-萤石-有机质-黄铁矿(Py-2)阶段;LA-ICP-MS分析结果显示两阶段方解石中稀土元素在球粒陨石标准化配分模式图上具有明显的左倾特征,Y/Ho值集中于23.37～45.79和31.47～45.87.这些地球化学特征与围岩和下伏牛蹄塘组富铀泥岩相似,因此推测围岩娄山关组白云岩和桐梓组白云岩以及下伏牛蹄塘组富铀泥岩共同为沙坪铀矿点提供了成矿物质.

贵州剑河圭深铀矿床位于南明向斜东南翼,含矿岩系为老堡组和牛蹄塘组碳质页岩,围岩为老堡组硅质岩.为了探究该矿床的物质来源和沉积环境,文章在野外地质调查的基础上,开展了全岩元素地球化学特征研究,结果表明:硅质岩和碳质页岩的Zr/Hf和Y/Ho值变化较大,且具有平坦的稀土元素配分模式,指示成岩成矿物质来源受大陆风化和海水作用共同控制;硅质岩和碳质页岩都具有较低的Th/U值(最大值为0.25)、较高的δU值(最小值为1.84)和V/(V+Ni)值(最小值为0.87),在稀土元素配分模式图上具有Ce负异常,指示圭深铀矿床形成于缺氧还原的沉积环境.

This paper is the result of ecological geological survey engineering.[Objective]The origin and enrichment of trace elements such as Cd and As in soil-water-atmosphere dust fall are the focus of environmental geology research.The quantitative research on migration and enrichment of trace elements such as Cd and As in soilirrigation-rain-atmosphere dust fall system was carried out in Huishui.It is of great significance for agricultural production and agricultural products planting in this region.[Methods]Taking the samples of surface soil,irrigation water,rainwater and atmospheric dust-fall from Huishui County of Guizhou Province as research objects,this paper analyzes the geochemical characteristics of trace elements such as Cd and As.[Results]The results show that the study area is dominated by acid soil.Cd is positively correlated with As,Cr,Hg,Mn,Ni,Pb,Zn and pH while it is negatively correlated with Cu and Se in the 147 topsoil elements.The 34 irrigation water samples are mainly As,B,F - ,Se and Zn.The single factor pollution index and Nemero composite index of heavy metal elements from irrigation water are Level 1,belonging to the clean range,which indicates that the water quality of irrigation water is up to the standard.Among the 5 rainwater and atmospheric dust-fall samples,the atmospheric dust-fall mainly includes As,Cd,Cr,Hg and Pb and the main components of rainwater are As,B,Cd,Cr 6+ ,F - ,Ge,Hg,Pb,Se and Zn.[Conclusions]The evaluation results show that the Cd single factor pollution index is the highest,and the Nemero composite pollution index is arranged as followed:Hongqi Village,Xiantang Town＞Yangma Village,Lushan Town＞Lianjiang Street,Dapo Village＞Haohuahong Village,Haohuahong Town＞Lixin Village,Baijin Town.The irrigation water quality reaches the standard without heavy metal pollution.The order of the average annual flux density of atmospheric dust-fall is B＞Se＞Pb＞Zn＞Cr＞As＞F＞Cd＞Ge＞Hg.The average total amount of atmospheric dust-fall in the study area is 89 g·m -2 ·a -1 ,which is slightly lower than that of some cities and provinces in China.The comparison between surface soil and atmospheric dust-fall shows that Cd,Cr,Pb,Zn are rich and Se is poor in terms of the comparison between surface soil and annual rainwater flux,indicating that rainwater contributes largely to Se.Compared with rainwater,elements in the atmospheric dust-fall are higher except Hg.Compared the atmospheric dust-fall annual flux to the average surface soil,all elements are in deficit except Se.And compared the atmospheric dust-fall annual flux to the irrigation water contents,As,Hg,Se are enriched while Cr is depleted.So it can be concluded that the heavy metal element Cd pollution in surface soil comes from geological background,industrial wastes and coal burning while the atmospheric dust-fall mainly comes from coal burning dust and traffic dust.

为了查明黔南碳酸盐岩区水稻-根系中土硒、重金属的迁移与积累特征、水稻-土壤系统硒与重金属元素的相互关系,研究影响水稻对硒和重金属元素吸收的影响因素.本文通过对黔南独山—荔波一带稻作区水稻及对应根系土样品各项指标的采集分析,测试了水稻的Se、As、Cd、Cr、Pb、Hg含量与根系土的Se、As、Cd、Cr、Pb、Hg、SiO2、Al2O3、Fe2O3、pH、SOM含量.结果表明根系土中Se、Cd、Cr、Pb、As呈伴生关系,稻米对Se和重金属的富集能力为:Cd＞Se＞Cr＞As.其中根系土中Al2O3、Fe2O3、SOM与硒、重金属为正相关关系,稻米KSe与根系土中Se、Cr、Hg、Pb、As、Al2O3、Fe2O3、SOM呈极显著负相关关系,稻米中Se、Cd富集系数KCr、KCd与根系土中Se、Al2O3、TFe2O3、SOM为极显著负相关关系.研究区有生产富硒大米的条件,可通过适当的农艺措施改善土壤的理化条件,在降低重金属Cd、Cr的危害的同时提高水稻对Se的吸收富集,达到对重金属元素超标富硒耕地的科学开发利用.

三穗铀矿床位于黔中—湘西北铀成矿带内,产于震旦—寒武系老堡组炭质泥岩中,是贵州省近年勘查发现的第一个大型铀矿床.[研究目的]鉴于黔东地区铀矿成矿规律、富集机理及矿石矿物学等研究程度低,查明典型铀矿床矿石矿物组合及化学组分,探讨成矿环境,揭示成矿过程,深化成矿理论认识,将为促进区域成矿预测、扩大找矿勘查成果及丰富该类型铀矿成矿理论提供科学依据.[研究方法]基于三穗铀矿床地质、地球化学特征,通过电子探针、扫描电镜等测试,分析了铀成矿机理及成岩成矿的环境演化.[研究结果]本区含铀岩系老堡组形成于震旦纪/寒武纪转折期的陆缘裂谷和陆缘裂陷缺氧还原环境,铀成矿初始物源与海底火山活动有关;铀矿石主要由铀矿物、铁矿物、黏土矿物、有机质及白云石、石英(或玉髓)、重晶石、方解石等组成,呈微晶—隐晶结构、微晶—粉晶晶粒状结构,层状、纹层状构造;铀矿物丰富,主要有沥青铀矿、硅钙铀矿、硒铅铀矿、钛铀矿、磷铀矿及水碳铀等,以纳米—微米级粒状、柱状(粒径多<10μm)、细脉状、或隐晶质形式赋存于有机质、铁质、黏土矿物等聚铀矿物中.[结论]三穗铀矿床形成物源具有多源性,与雪峰期海底火山作用带来部分成矿物质、燕山—喜马拉雅期成矿流体在运移的途中不断浸取地层内的成矿物质密切相关,经历了铀初始富集、氧化淋滤及热液叠加再富集过程,成因属典型的碳硅泥岩型.三穗铀矿床中发现大量铀矿物显示,铀富集程度高、成矿作用强,找矿远景好、潜力大.

黔东铜仁地区广泛发育早寒武世黑色岩系,已发现多个中小型含铀磷块岩型矿床,为探究其成因,文章选取矿化现象较好的大坳、牛角冲、溪门口和新冲等地出露的老堡组-牛蹄塘组剖面开展系统采样,进行岩石地球化学特征研究.分析结果显示老堡组硅质岩、磷块岩和牛蹄塘组碳质页岩具有介于陆源物质和海底热液之间的Fe2O3/TiO2、Al2O3/(Al2O3+Fe2O3+MnO)、Zr/Hf、Y/Ho值,以及相对平坦的稀土元素配分模式,揭示铜仁地区磷块岩型铀矿形成于受陆源物质输入影响的正常海相沉积环境,部分受到海底热液影响;硅质岩、磷块岩和碳质页岩具有高δU值(＞1)、低Th/U值(＜2)、高V/(V+Ni)值(＞0.6)和明显的Ce负异常,进一步表明这些含铀磷块岩型形成于贫氧-缺氧的还原环境.综合分析认为由于Rodinia超大陆裂解,受大陆风化和海底热液共同作用,在还原条件下形成了具有正常海水沉积和海底热液作用混合成因的含铀磷块岩.

黔北地区为贵州省碳酸盐型铀矿(化)集中区,但有关铀矿床的研究资料却十分缺乏.通过在黔北地区对典型碳酸盐型铀矿床(点)进行野外地质调查、探槽和坑道铀矿石样品采集,开展了显微岩相学、扫描电镜-能谱分析、激光拉曼、碳氧同位素等研究.结果表明,铀矿体受断裂构造控制,铀矿脉中心部位因富含有机质而呈黑色、深灰色,铀矿石中的铀矿物主要为铀石,铀石与黄铁矿及"黑色"的有机质紧密共生,激光拉曼研究显示其具有焦沥青的特征.铀矿石中富含显示强浅蓝色荧光的轻质油包裹体,且严格平行于含矿微裂隙,指示了铀矿物的形成可能与烃类流体有关.碳同位素分析进一步证实了铀矿石中的有机质与其赋矿碳酸盐岩表现出明显的异源特征,且与贵州典型古油藏的碳同位素具有相似性,指示焦沥青可能来源于深部侵位的古油藏.微量、稀土元素分析表明,铀矿石的微量、稀土元素与深部牛蹄塘组富铀泥岩具有可比性.研究认为,黔北碳酸盐型铀矿床的形成与深部侵位的古油藏有关,铀成矿物质可能主要来源于深部牛蹄塘组富铀泥岩,铀矿床为受构造和古油藏联合控制的热液型铀矿床.

为研究贵州省惠水县农作物-土壤重金属污染现状,采集农作物-根系土、土壤剖面-成土母岩样品,测定Cd、Hg、As、Pb、Cr、Cu、Ni、Zn和pH的含量,选用富集系数、健康风险评估、单因子污染指数法、地累积指数法对农作物-土壤重金属污染现状进行了评价.研究表明:(1)农作物中水稻、玉米和油菜中以Cd累积为主,其次为Pb、Cr、Hg;金钱橘无重金属超标;农作物富集系数中Cd是Pb、As、Cr的几倍至上百倍;经玉米、油菜、金钱橘摄入重金属的人体健康风险很低;水稻中Cd的THQ大于1,对人体的健康有一定的风险;(2)单因子污染指数研究结果说明根系土以Cd污染为主;Ig揭示根系土中Hg、Cd、Cr超标可能受人类活动影响较大;(3)从土壤剖面-成土母岩系统来看,As、Cd、Cu具有继承性,尤其Cd含量在成土母岩、土壤剖面、根系土、农作物中含量超标,有部分来源于成土母岩高背景值.

通过系统取样和分析测试对贵州惠水涟江高效农业园区土壤重金属污染现状进行了科学调查与研究,并采用单因子污染指数、内梅罗污染指数、富集因子法和潜在生态污染指数法对其土壤重金属污染现状、元素富集程度及潜在生态风险进行了综合评价.结果表明:222个样品的pH值<7.0,占比66％,这表明该园区以酸性土为主;从综合评价结果来看,园区土壤的重金属污染程度轻微,元素富集程度不高,对环境的生态污染程度轻微;园区内的重金属(Cd和Hg)污染,其来源可能受地质背景、工业三废、燃煤、长期施肥等综合影响.

Research on topics such as geological–tectonic evolution, metallogenic models of deposits (gold, mercury, lead, zinc, etc.), and ore-forming fluids’ evolution has been conducted in Guizhou. However, few studies have been conducted on uranium (U) deposits (especially carbonate-hosted U deposits). Moreover, the relationship between hydrocarbon fluids and U-mineralization has not been addressed at all. Typical carbonate-hosted U deposits (including some ore spots) in Guizhou Province have been investigated through close field work, petrography, mineralogical, micro-spectroscopy, organic geochemical and C isotope studies. The central part of the U-ore body is often black (the black alternation zone) at the outcrop, and its sides are gray and gray-brown (the gray alternation zone); the color gradually becomes lighter (black to gray) from the center of the ore body out to the sides. Petrographic observations, microscopic laser Raman spectroscopy, and infrared spectroscopic and scanning electron microscope analyses have indicated that U-minerals (pitchblende and coffinite), pyrite and “black” organic matter (OM) are closely co-dependent, with the OM having the typical characteristics of bitumen. Large light oil fluid inclusions were found in gray alternation rocks (besides the U-ore body) with strong light blue fluorescence properties, indicating that hydrocarbon fluids and U-minerals may came from the same U-bearing hydrocarbon fluids. The values of the 13C isotope value, a biomarker of OM and trace elements, REEs in U-ores, were found to be similar here to those in the local paleo-petroleum reservoir, indicating that the bitumen may originate from the deeply intruding paleo-petroleum reservoir. The precipitation of U is related to the cracking differentiation of hydrocarbon fluids. As result, the carbonate-hosted U-mineralization in Guizhou is neither of a sedimentary diagenesis type, nor of a sedimentary diagenesis superimposed leaching hydrothermal transformation type, as have been described by previous scholars. To be exact, the U deposit is controlled by fault and hydrocarbon fluids, and so it can be defined as a structural hydrocarbon–carbonate-type U deposit. A new U-mineralization model was proposed in this study. Here, U, molybdenum, and other metals were mainly found in the black rocks in the lower stratum (presumably Niutitang Formation), having migrated together with hydrocarbon fluids in the form of tiny mineral inclusions. The hydrocarbon fluids (containing some brine) caused cracking and differentiation upon entering the fracture zone, at which point the ore-forming materials (U, pyrite, and other metals) were released and precipitated.

紫砂壶的造型万千,变化莫测,或方或圆,万变不离其宗.紫砂五色土是大自然馈赠的宝物,集天地之精华,是最自然的艺术材质,让紫砂壶成为最具自然的文化艺术品.《德钟壶》端庄稳重,比例协调,整壶的触感温润如玉,经过茶水泡养过后更加细腻光泽,享受着紫砂的美好,陶冶身心,了解紫砂文化其中的内涵与情感,感受其中长盛不衰的艺术生命力.

紫砂壶是陶瓷艺术中极具特色与个性的一种艺术类别,这都是凭借着紫砂壶独一无二的材质、精巧绝伦的工艺与富有丰富内涵的文化意蕴.紫砂艺术是一种包容性极强的艺术形式,它可以将其他中国传统艺术或元素互相融合,做到一加一大于二的艺术效果,足以见得其艺术特点的广泛性和包容性.今天这件紫砂《三脚水平壶》通过艺人的设计与传统技艺的结合,让我们感受到其中的造型艺术与文化内涵,同时也展现出传统与创新的互相结合,将作品旺盛的生命力展现得淋漓尽致.

Longwan deposit is located in the central Guizhou-northwestern Hunan uranium mineralization belt. It is the first discovered large-scale uranium deposit in Guizhou Province in recent years. Taking Longwan deposit as the research object, this study has focused on its mineralogy, geochemistry and genesis. The result shows that the primary uranium mineral in this ore consists mainly of pitchblende, while the secondary uranium ores formed under surface conditions are well developed, mainly including silicon calcium uranium, selenium, lead, titanium, uranium and urinal phosphate mineral, etc., with nanometer-micro level of granular ( particle size of <10,m), stringer, or implicit crystalline forms occurring in in the uranium minerals ( organic matter, clay minerals, etc.). The ore-forming materials mainly come from ore-bearing horizon, and some may come from basement magmatic rocks. The ore-forming fluid is the mixture of deep fluid and meteoric precipitation. The enrichment of uranium and associated elements is closely related to carbonaceous mudstone with abundance of organic matter, phosphate mineral, iron ore and clay minerals. The formation of uranium ore is controlled by such factors as stratum ( Laobao Formation), lithology ( carbonaceous mudstones), structure (fault of Sansui syncline and oblique tangential syncline, interlayer fault), sedimentary environment ( marine reductive sedimentary environment of continental rifts and rifts). It experienced the mineralization process of uranium enrichment during the formation of ore-bearing rock series under the action of seafloor jets in Xuefeng period, followed by leaching, hydrothermal superposition and re-enrichment under the background of intraplate extensional tectonic movement in Yanshan-Himalaya period, is described. Epigenetic metallogenic characteristics are obvious, and the deposit belongs to sedimentary-hydrothermal superposition transformation type. The research results of this paper have important guiding role and reference significance for promoting uranium mineralization prediction and prospecting exploration and enriching carbonaceous and siliceous mudstone uranium mineralization theory in eastern Guizhou.

内蒙古新地沟金矿是中型绿岩型金矿床,但已属于严重资源危机的矿山,急待寻找接替资源,因此对新地沟金矿床进行深部远景预测具有十分重要的意义.本文根据找矿矿物学和成因矿物学理论,利用显微镜、电子探针及热电仪系统分析新地沟金矿床不同标高和矿段中黄铁矿的热电型标型特征,研究结果表明:新地沟金矿床中黄铁矿的晶型以立方体、五角十二面体及聚形为主;热电系数变化主要集中在-331.10～340.20μV· °C-1范围内,导电型多以N型为主,约占总含量的80％;成矿温度主要集中于250～340℃,属于中温矿床.黄铁矿热电性参数XNP变化范围较大,估算矿体剥蚀率为67.96％～74.31％.通过对黄铁矿导型的空间分布规律和矿体剥蚀分析表明:油篓沟矿段位于矿体中底部,向深部可能有小规模延伸,小西沟矿段钻孔ZK106在深部有较大规模的延伸,其矿化前景最好;小西沟矿段钻孔ZK102深部矿化前景次之;大汗青矿段钻孔ZK2802其深部矿化前景较差.综合分析认为,该矿床深部具有较好的找矿潜力.

本文通过总结矿区地质概况、矿体地质特征和矿石地质特征,并在总结前人资料的基础上,探讨成矿岩相古地理、成矿物质来源和成矿形成过程,初步总结了坛罐窑铝土矿矿床成因及成矿规律,确定了找矿标志.

贞丰皎贯金矿区成矿条件十分有利,为加强区内地质找矿工作,在总结区域地质背景、矿区及矿床地质特征的基础上,结合地层地球化学、断裂构造地球化学和次生晕地球化学工作成果,详细分析了区内地层地球化学特征、断裂构造地球化学特征及次生晕地球化学特征.研究表明:①区内赋金层位主要为二叠系下统峨眉山玄武岩组,次为二叠系上统领薅组一段,岩性主要为凝灰质黏土岩、砂质黏土岩及粉砂岩,为主要的矿源层;②矿体的形成受断裂、地层、岩性、围岩蚀变等多重因素控制,断裂构造为主要控矿条件,与土壤地球化学异常的空间分布关系密切;③围岩蚀变以硅化、黄铁矿化、毒砂为主;④矿区采用次生晕扫面方法确定的异常区与地质构造、矿(化)体较吻合,且规律性较强,并通过工程验证,发现了多个矿(化)体;⑤矿区金矿与构造、蚀变密切相关,在强硅化形成的微—细石英脉与黄铁矿化、黏土化及褐铁矿化相互叠加时,金矿体品位较富,为寻找金矿的有利标志.在上述分析的基础上,进一步分析认为:①矿区有利的找矿标志为地层岩性、岩溶不整合面、构造、蚀变、地球化学异常等;②区内纳哥地段、卡务地段、佐锡拉旦沟地段金矿找矿前景较好,值得进一步开展工作.

浅成低温热液系统可能是深部斑岩成矿系统的表征.在澜沧裂谷,喜山期花岗斑岩隐伏侵入裂谷中部下石炭统依柳组玄武质火山岩地层,形成了与老厂大型钼铜银铅锌多金属矿床有关的斑岩-夕卡岩型热液蚀变体系,在浅表的碳酸盐岩地层中则形成脉状银铅锌矿化.裂谷西部的大黑山勘查区下石炭统地层为南段组碎屑岩,深部隐伏的花岗斑岩可能形成不同于老厂的热液蚀变体系,对大黑山勘查区一个综合垂直剖面的初步研究表明:(1)深部热液体系在南段组中以形成具有明显Eu正异常(δEu=1.58)的石英网脉为特征,并且具有与老厂蚀变斑岩相似的Pb-Bi-Ag-Zn-Cu富集模式但Mo明显亏损,暗示深部可能存在与老厂矿区相同的花岗斑岩及Mo的矿化.(2)深部热液体系在C1n/C2+3岩性界面与低温天水系统混合,在C2+3白云岩中形成具有突出Eu正异常(δEu最高达5.71)的铁锰方解石化,并在近40 m的蚀变带内显示出Pb-Zn-Ag矿化异常;蚀变过程中Mg的带出与Ca-Fe-Mn的带入具有良好的相关性,并形成继续向上运移的低温Mg-Mn热液.(3)低温Mg-Mn热液在上覆二叠系生物碎屑灰岩中形成热液角砾白云岩化蚀变,大黑山勘查区地表以线型正地形的黑山梁子为代表;热液角砾白云岩化表现为弱的Eu正异常、Sr-U明显亏损和强烈的Mn富集,是地表锰银矿化的重要物源.大黑山综合剖面的研究确证了地表灰岩中广泛存在的各种形式的热液角砾白云岩化是深部岩浆热液活动的具体体现,是非常有利的找矿标志.