【作者】 高建国；

【导师】 秦德先；

【作者基本信息】 昆明理工大学 ， 矿产普查与勘探， 2007， 博士

【摘要】 本博士论文“澜沧老厂铅锌多金属矿床综合成矿信息与靶区定量预测“是结合本人所负责的云南省省院省校合作项目《云南澜沧老厂银铅锌多金属矿床立体定位预测与增储研究》（编号：2003ADBEA34A025）科研项目而选题。云南澜沧铅矿经数十年来对资源的开发和利用，导致目前资源逐渐萎缩，地表高品位炉碴和砂泥铅生产殆尽而转入深部开采，矿山保有地质储量不足，后备资源基地眉目不清，资源问题已成为严重制约矿山企业发展，甚至威胁企业生存的根本问题。矿山虽经数十年的发展，积累了较丰富的实践经验，但研究深度不够，严重地影响地质找探矿研究。矿产资源需求量的急剧增长与矿产资源寻找难度大、成功率低、成本高的矛盾日趋突出，仅仅依靠常规地质方法和手段是难以解决当前的资源危机，当务之急将利用现代科学技术手段和方法和新的地质理论，实施多学科、多兵种联合攻关，以期扩大资源储量，维持矿山正常生产，延长矿山服务年限，促进社会经济的可持续发展。本论文的研究旨于前人工作的基础上，系统地评价澜沧铅锌成矿带成矿地质条件，研究其成矿规律，对成矿区带找矿前景进行评估；应用现代数字信息与计算机技术、矿床遥感、古构造岩相学、地球化学、地球物理、数学地质等多学科的新技术、新方法和新理论，借助二次开发地理信息系统软件平台，集地质、物探、化探、遥感等空间信息为一体，研究各变量变化性和规律，建立定量预测模型（模式），进行立体定位预测和靶区优选，实施工程验证，其方法和理论推动区带资源的寻找、评价和理论创新。通过上述研究主要获取了以下成果和认识：1．成矿大地构造环境：从火山岩岩石化学、岩石地球化学的角度对澜沧老厂银铅锌多金属矿床形成的大地构造环境进行分析与判别，认为澜沧老厂银铅锌多金属矿区火山岩主要为碱性玄武岩、粗面玄武岩，个别系玄武质粗面安山岩，属玄武质—安山质类岩石；岩石TiO₂含量较高，稀土元素配分曲线为轻稀土富集的右倾型，微量元素原始地幔标准化曲线向右倾斜、Nb与Zr等元素的含量普遍较高、Th高度富集，具大陆型特点；玄武岩类岩石Th／Hf-Ta／Hf大地构造环境判别图解显示其主要为形成于大陆裂谷环境。2．火成岩岩相与矿体的关系：火山岩的岩相可分为爆发相、喷溢相、喷发沉积相和侵出相共四类，其中喷发沉积相与矿体的关系最为密切。例如，C₁⁸中喷发沉积相与矿体的产出具有直接关系，矿体一般产在具有一定厚度（通常5m以上喷发沉积相）和断裂构造通过的凝灰岩中；C₁⁷中矿体与喷发沉积相关系密切，主要产于喷发沉积相的顶层，多与灰黑色、黑色凝灰岩或有断裂通过的灰白色安山凝灰岩有关；C₁⁵⁺⁶中矿体基本，与喷发沉积相的灰黑色凝灰岩、灰白或灰黑色安山凝灰岩有关。3．矿床地球化学：矿石铅和岩石（碳酸盐岩、火山岩、花岗斑岩）铅的同位素组成平均值近似，铅来源具内在联系。从铅构造模式图中看出矿石铅来源比较复杂，为壳幔混合铅。火山岩和碳酸盐岩岩石铅与部分矿石铅可能来自围岩（矿源层）；花岗斑岩岩石铅源于上地壳，可能与矿床有一定的成因联系。硫同位素组成在零附近，具陨石硫特征，推测硫主要来源自玄武岩浆。矿床的方解石中δ¹³C_PDD值介于（-7.2—+2.8）ω‰，平均值为-2.06ω‰；δ¹⁸0值为（-0.18—+10.5）ω‰，平均值为+5.72ω‰。与碳酸岩方解石的δ¹³C值（+5—8）ω‰，δ¹⁸0值（+6—+8.5）ω‰比较，差异明显，推断矿体中方解石的碳是岩浆碳与地层（碳酸岩盐、火山岩）碳或岩浆与地层及海水碳的混合碳。石英流体包裹体的δD值为（-69.86—-93）ω‰，平均值为-86.8ω‰；δ¹⁸O_H2O值为（—1.53—+9.21）ω‰，平均值为+3.62ω‰。与岩浆水的δD值（—50——80）ω‰和δ¹⁸O值（+6—+9）ω‰比较有明显差异，推测成矿流体为岩浆水与海水或大气降水的混合水。4．地球物理信息：采用瞬变电磁法（TEM）、激发极化法（IP）和高精度磁法等有效的物理探矿方法获得了5个TEM低阻异常带、2个激电异常、2个磁法异常。综合全区激电、电阻率测深的反演计算结果，并结合地表出露和钻孔揭露情况，获得到了澜沧老厂铅矿区C₁地层界面等高线图。通过系统的地球物理勘查，获取了有用的地球物理找矿信息。5．元素地球化学：运用数理统计的方法理论对岩矿样品分析结果计算分析认为：主要成矿元素组合（铜、铅、锌、砷、锑、锡、银、金）高值异常区集中在断裂交汇部位，沿火山口机构边缘断续分布，成矿时处于偏高温火山环境，北象山北部高值异常区（7-12号勘探线）、南象山西南部高值异常区（147-149勘探线）为找矿有利部位；方差极大正交旋转矩阵表中：F1因子轴中可将Cu-Pb-Zn-As-Sb-Hg-Ag-Au等元素可视为块状黄铁矿型热水沉积成矿期；F2因子轴中可将Cu-Pb-Zn-As-Sb-Hg-Be-Sn-Mo-Y-Cr-Se-Yb-V-Nb-Ni-Ga等元素视为深部隐伏基性岩和酸性岩类的侵入对原热水沉积成矿矿床的改造作用。该区成矿作用主要为沉积、改造叠加两期成矿作用。6．遥感技术：对区域1／20万LandsatTM7个波段卫片、矿区1／2000快鸟数据进行了遥感信息解译；定性解释了线环形构造，并对线性构造进行等密度、平均方位、优益度、条数等定量化分析，定量解译了遥感地质综合数值化信息；利用数据融合技术，对研究区的遥感、物探、地球化学数据进行PCA融合处理，建立矿床遥感综合信息模型，进行了遥感成矿信息预测。研究表明：矿化信息与线性构造关系密切，矿区内大部分已知矿化点位于线环构造交汇交切部位。7．定量预测：根据多源地学信息数据库划分提取的各找矿标志及控矿要素10个（NW向断裂、有利赋矿层位、线性构造等），运用网格化单元（0.1Km×0.1Km），建立“找矿信息量模型”，计算出单变量（12个）信息量值、复合变量信息量值（2个）、综合信息量值和找矿信息量值，厘定找矿信息量值临界值（2.5），以此圈定4个成矿有利靶区，并对部分靶区进行验证。更多还原

【Abstract】 The doctoral dessertation title of Research on the Synthetic Metallogenic Information and the positioning location and quantitative Prediction of Resources Targets for Lancang-Laochang Lead Zinc-polymetallic Deposit is selected based on the cooperative item of Yunnan province and China academy/university of research on the reserves increase and the stereo prediction of deposits of Lancang-Laochang Silver Lead Zinc-polymetallic Deposit （serial number: 2003ADBEA34A025） which I preside in.The research goal is to evaluate the metallogenic geological settings and study the metallogenic laws systematically with the purpose of mineral exploration prospect for Lancang-Laochang Lead Zinc-polymetallic Deposit. Based on the application of new technologies, new theories or disciplines such as Digital information and computer technology, Remote sensing for deposits, Paleotectonics and paleolithofaces, Geochemistry, Geophysics, Mathematical Geology, Geographic information system （GIS） etc., the author has analyzed the spatial information of geological information, geophysical information, geochemical information and remote sensing information wholly with the help of the second developing software desktop of GIS, studied the changeable law of variables, established the quantitative and stereo mineral prospecting modes, specified and optimized the quantitative Prediction of Resources Targets. From these research items, the following conclusions have been drawn:No.1 Metallogenic geotectonic environments: Through the analysis or differentiation of the tectonic geological structure environment which formed the deposit with the characteristics of the petrochemistry and petrogeochemistry of the volcanic rocks, the author concludes that the volcanic rocks in the Lancang-Laochang Lead Zinc-polymetallic Deposit district belong to the rock types of basalt-andesite series such as alkalescence basalt, coarse face basalt and so on. According to the geochemical characteristics such as high contents of TiO₂, right inclination type of rich LREE ration curve, right inclination type of primary mantle standardized curve of microelement, high content of Nb, Zr, Th, we can think the vocanic rocks have the continental features. And the illustration of the Th/Hf-Ta/Hf for tectonics environment judgement indicates that the basalts are formed in the condition of continental ridge. No.2 The relationship between vocanic rocks’s lithofacies and orebodies: The lithofacies of the vocanic rocks can be divided into four types: eruption, overflow, eruption sediment and extrude, meanwhile eruption sediment is very closed to orebodies. There is a direct relationship between the eruption sediment face and the orebodies in C₁⁸. The orebodies are often found in the definite thickness ,usually over 5m, tuff which has formed in the condition of faults. The orebody of C₁⁷, with the only relationship to the eruption sediment face, lies on the top part of the eruption sediment face. It mostly relates to the light black, black tuff or hoar andesite-like tuff. The orebodies in C₁⁵⁺⁶ almost lie on the eruption sediment face. They mostly relate to the grey-black tuff, the hoar or grey-black andesite-like tuff and marble. So, there is a definite relationship between the orebodies and the eruption sediment face.No.3 Geochemistry deposit: The approximate mean content of Pb isotope in the ore and wallrocks （carbonate rocks, volcanic rocks and granite porphyry） indicates the sources of Pb from these types of rocks are inherently related. From the construct Pb mode map, we can see that the source of Pb in the ore is very complex and the Pb belong to crust-mantle admixture Pb. The Pb in the volcanic rocks, carbonate rocks and part ore may all be from wallrocks （strata bearing original minerals）.The Pb in the granite porphyry comes from the crust and there may be definite genetic relationship between it and deposit. The fact that the content of S isotope is near zero, with the characteristic of the S in the meteorolite, indicates the contents of S are mainly from basalts and partly from biology. According to the analysis of the calcites, the apparent differences between the comtent of d¹³C_PDB, varying from -7.2ω‰to +2.8ω‰with the mean value of -2.06ω‰, the comtent of d¹⁸O, varying from -0.18ω‰to +10.5ω‰with the mean value of +5.72ω‰and the comtent of d¹³C, varying from -5ω‰to -8ω‰, the comtent of d¹⁸O, varying from +6ω‰to +8.5ω‰indicate the C from the calcites in the orebody originates from magma or strata or the admixture of magma, strata and seawater, and the apparent differences between the comtent of dD,varying from -69.86ω‰to -93ω‰with the mean value of -86.8ω‰as well as the comtent of d¹⁸O_H2O,varying from -1.53ω‰to +9.21ω‰with the mean value of +3.62ω‰in the liquid inclusion of Quartz and the comtent of dD,varying from -50ω‰to -80ω‰as wellas the comtent of d₁₈O, varying from +6ω‰to +9ω‰indicate that the metallogenic liquid may be water from magma and seawater or atmospheric precipitation.No.4 Geophysical information: Five abnormal TEM low resistance areas, two abnormal electricity areas and two abnormal magnetic areas have been gotten through adopting the effective geophysical prospecting techniques such as TEM, IP and high precision of magnetism and so on. Based on the comprehensively calculated output of electricity and resistance sound, which are combined with geological characteristics from earth surface and drills, the stratum C₁ interface contour map has been acquired. So, by means of systematically geophysical prospecting, a large quantity of useful geophysical prospecting information has been obtained.No.5 Geochemistry of elements: It can be found after analyzing the sample analysis results from wallrocks and ores that the high value abnormity of the main metallogenic elements composition concentrates on the crossing points of the different faults, appearing around the crater structure occasionally. This indicates the metallogenic temperature is a little high because of the volcano environment. So, there are two available prospecting areas which lie in the high value abnormity of the north part of Beixiang mountain and the southwest part of the Nanxiang mountain. From the matrix table of the variance maximum vertical rotation, we can deduce two research outcomes: F1 factor bearing the weight of Cu-Pb-Zn-As-Sb-Hg-Ag-Au stands for the massive pyrite exhaiative hydrothermal sedimentary mineralization epoch and F2 factor bearing the weight of Cu-Pb-Zn-As-Sb-Hg-Be-Sn-Mo-Y-Cr-Se-Yb-V-Nb-Ni-Ga implies the superimposed mineralization on the hydrothermal sedimentary deposit by the intrusion of deeply concealed basic igneous rocks and acidity igneous rocks. Therefore, there are two main metallogenic epoch of sedimentation, reconstruction and overlapping.No.6 Remote-sensing technology: After RS information interpretation on the seven wave bands of the regional 1;200000 LandsatTM and the Quickbird data, the author gives an explain to the line-ring structure qualitatively , analyzes the density ,number, quantative of optimize and benefits and the mean orientation of line structure and interprets the RS geological comprehensive digital information quantatively. Adopting the data amalgamation, the author manipulates the RS data, geophysical data, geochemical data by means of PCA and establishes a deposit RS comprehensive information prospecting modes for the purpose of RS metallogenic information prediction. The research results make it clear that there is a close relationship between the mineralization information and the linear geological structure, and most deposits lie in the crossing parts of line and ring geological structure.No.7 Quantitative prediction: With the help of prospecting signs, mine control factors, the grid cell （0.1Km×0.1Km） calculating methods, the author has established the prospecting information value modes and calculated the simple variable information value, the compound variable information value, the comprehensive information value and predicting information value. At last, the critical prospecting information value （2.5）. Based on the critical value, four favourable prospecting prediction targets have been pointed out. Some of them are validated effectively.更多还原