【作者】 张宇峰；

【导师】 吴国学；

【作者基本信息】 吉林大学 ， 矿产普查与勘探， 2012， 硕士

【摘要】 塔尔气地区位于大兴安岭中北段，是西伯利亚板块东南缘的增生大陆边缘。区域成矿位置处于古亚洲成矿域和环太平洋成矿域的叠加部位，是我国重要的有色、贵金属成矿区带。经研究显示，该区具有良好的铅锌银多金属成矿潜力。由于基础地质和矿产勘查工作程度较低，区内发现的中大型矿床较少。近年来，随着地质勘查投入的增加和研究程度的加深，取得了突破性的进展。本次研究，在1:5万的矿产地质调查的基础上，综合分析塔尔气地区地质、物探、化探、遥感等信息特征，了解成矿背景和控矿因素，总结矿产分布规律，选用有效的综合信息成矿预测方法，圈出有利的找矿远景区，明确该区找矿方向，进一步指导后续找矿工作。区内出露的地层为新元古代青白口系佳疙疸组和震旦系额尔古纳河组；中生代中侏罗世塔木兰沟组、晚侏罗系满克头鄂博组、玛尼吐组、白音高老组；新生代以后有大黑沟组和第四系。区内岩浆活动主要分两个期，晚古生代和中生代，晚古生代主要表现为强烈的岩浆作用，出露石炭纪、二叠纪花岗岩。中生代以火山作用为主，其岩性为中—酸性火山岩，同时伴有中酸性脉岩侵入，而这些脉岩与燕山期成矿有密切关系。北东向构造是区内控岩、控矿构造，而北西、北东向次级断裂是导矿、容矿构造。根据区内已发现的矿床（点），认为NE和NW向构造交汇部位是最有利的成矿位置。土壤地球化学异常是成矿作用的直接或间接反映，在区域矿产普查、矿区及其外围找矿等方面具有重要的指示作用。塔尔气地区次生晕显示出较明显的元素组合异常，其中最有意义的元素组合异常为Pb、Zn、Ag，当元素组合异常套合较好，异常规模大，则可作为有效的地球化学找矿信息，进行成矿预测。因区内北东向构造控制明显，土壤地球化学异常整体呈NE向带状展布，主要异常元素有Pb、Zn、Ag、Mo，与该区找矿主攻矿种一致。研究区内岩石的磁化率差异比较明显，强度在几~1000（-5SI）之间变化，不同岩性其磁化率有显著差异，这对地质填图过程中岩性界线划分有指示意义。但区内火山岩的磁化率变化范围较大，对岩性的判别有干扰作用；岩石的激化率值均较低，在2%左右，而电阻率呈高阻特征。遥感影像解译环状构造和线性构造非常发育，以NE、NW、近NS、近EW向为主，构成了区内构造格架；环状构造大多以环套环、环切环的形式成群出现，有时也有单独大环出现，这些环状构造大多与断裂、火山及岩浆活动有关，是重要的成矿预测标志之一。通过对塔尔气地区1:5万综合信息研究，总结分析有效的成矿地质、地球化学、地球物理和遥感解译等成矿预测信息，对研究区进行了成矿远景区预测，圈定出10处不同级别的成矿远景区，其中Ⅰ级4处，Ⅱ级5处，Ⅲ级1处。在1:5万成矿预测的基础上，结合1:1万地质、土壤地球化学、高精度磁测、激电中梯特征及综合剖面等综合信息，对比典型矿床找矿模型，对大南沟远景区进行了1:1万综合信息成矿预测。预测远景区内有利成矿部位，并开展探槽工程查证，控制了4条脉岩，均发生硅化、绢云母化、黄铁矿化、绿泥石化等。化学样品测试分析结果显示：Pb（最高0.36%）和Au均达到边界品位，同时，Ag和Zn也具有明显的矿化显示。综上，在塔尔气地区共发现4个矿点，分别为大南沟铅-锌-银-金多金属矿点、小南沟钼矿点、苏格河金-银-锌多金属矿点和中心沟金铜矿点。本次工作的成果体现了综合信息方法应用于塔尔气地区成矿预测的可行性和有效性，这为塔尔气地区后续找矿工作指明了方向。更多还原

【Abstract】 Ta`erqi survey area is located at Medium-northern part of Daxing’anling Mountain, which isaccretionary continental edge of the southeast margin of Siberian plate. Regionally, thismetallogenic belt is a superimposed part of ancient Asia metallogenic domain andCircum-Pacific metallogenic domain, and it is also a significant nonferrous and noble metalmetallogentic province in China. Depending on our survey, it suggests that Ta`erqi area hasperspectives for poly-metal Pb-Zn-Ag mineralization. Owing to the lack of basic geology andmineral exploration study, medium or large ore deposits are rarely discovered in this area.Recently, with the increasing investigation of exploration and the deepening of the researchdegree, a breakthrough has been made. On the basis of mineral resources geological survey of1/50000, we comprehensively analyze the characteristics of geological, geophysical,geochemical and remote sensing information about this area, find out metallogenic settings andfactors controlled ore forming, summarize the rules of the mineral resource distribution, chooseeffective method of synthetic information and metallogenic prognosis, todelineate favorablemetallogenic potential areas and orient the prospecting area, which will be guide for thefollowing work on ore exploration.The main strata in this area are:1) Neo-Proterozoic Qnj, Ze;2) Mesozoic J2tm, J3mk, J3mnand J3b;3) Cenozoic, Qp3d and Qh. Magmatic activities in this area are divided into two period:the one is in Late Paleozoic and the other in Mesozoic. The former is charactered by intensemagmatism with outcrops of Carboniferous and Permian granite; the latter is reflected involcanism, whose lithology is medium-acidic volcanic rocks, along with medium-acidicdyke,which is closely related to Yanshanian mineralization. The structures of northeast controlthe rock and ore body, and the secondary northwest and northeast faults provide channels forfluid and place for ore forming. According to mineral deposits discovered, we consider that thejoints of NE and NW structures are the favourable metallogenic position.Soil geochemical anomalies are directly or indirectly reflection of mineralization. It has theimportant indicative function on regional mineral deposits prospecting and mining area and itsperiphery prospecting and so on. Secondary halo in Ta`erqi displays evidently abnormal element assemblage. The most significative abnormal element assemblage is Pb-Zn-Ag. When abnormalelements superimpose well and anomaly be a large scale, the abnormal assemblage can be aneffective tool of geochemical information for metallogenic prognosis. With the obvious controlof NE structure, soil geochemical anomalies are north-eastern stretching belt as a whole. Themain abnormal assemblage is Pb-Zn-Ag-Mo, which coincides with chief prospecting mineralvarieties in this area.The magnetic suspectibility of the rock this area differs obviously, with the intensity of afew to1000(-5SI). Different rocks correspond to different suspectibility, which can indicateboundary of different lithology in geological mapping. It is an interferential factor thatsuspectility of volcanic rocks ranges largely. Susceptibility of rocks is low, with the value of±2%,but resistivity shows the characteristics of high value. Basis on the RS, this area widely developsring and linear structures, which include NE,NW,NS and EW forming the structure framework ofthis area. Ring structures mainly infest forming the loop-de-looping and overlapping rings, andsometimes occurred alone as a large ring. Ring structures are correlated to faults, volcanoactivity and magmatism, to be a important mark on metallogenic prognosis.According to the study on Taerqi1/50000synthetic information and analysis of geologicalcondition of mineralization, geochemistry, geophysics and RS, the author makes a metallogenicprognosis and delineates10different grades of prospects which contain4points in gradeⅠ,5points grade Ⅱ, and1points grade Ⅲ. Based on the above, in combination with thecomprehensive information of1/10000geological mapping, soil geochemical, high-precisionmagnetic measurement, IP intermediate gradient and cross section, contrasted with typicaldeposit propecting pattern, a metallogenic prognosis of1/10000has been made. After forecastingthe favourable metallogenic positions, we perform the engineering check of prospecting trench,consequently control4rock veins, which all underwent alterations of silicification, sericitization,pyritization and choritization. The analysis of chemical samples measurement show that Pb(highest to0.36%) and Au have reached cut-off grade, and Ag and Zn also have the evident markof mineralization.To summarize,4ore occurrence have been discovered in Ta`erqi, they areDanangou Pb-Zn-Ag-Au, Xiaonangou Mo, Sugehe Au-Ag-Zn poly-metal and ZhongxingouAu-Cu spots.This work embodies the feasibility and availability of the synthetic information in themetallogenic prognosis in Ta`erqi, which guides the further prospecting in Ta`erqi.更多还原