Ore-forming Conditions and Prospecting in the West Kunlun Area,Xinjiang, China

The West Kunlun ore-forming belt is located between the northwestern Qinghai-Tibet Plateau and southwestern Tarim Basin. It situated between the Paleo-Asian Tectonic Domain and Tethyan Tectonic Domain. It is an important component of the giant tectonic belt in central China (the Kunlun-Qilian-Qinling Tectonic Belt or the Central Orogenic Belt). Many known ore-forming belts such as the Kunlun-Qilian Qinling ore-forming zone, Sanjiang (or Three river) ore-forming zone, Central Asian ore-forming zone, etc. pass through the West Kunlun area. Three ore-forming zones and seven ore-forming subzones were classified, and eighteen mineralization areas were marked. It is indicated that the West Kunlun area is one of the most favorable region for finding out large and superlarge ore deposits.

Ore-forming Fluid and Mineral Source of the Hongshi Copper Deposit in the Kalatage Area, East Tianshan, Xinjiang, NW China

The Hongshi copper deposit is located in the middle of the Kalatage ore district in the northern segment of the Dananhu-Tousuquan island-arc belt in East Tianshan, Xinjiang, NW China. This study analyses the fluid inclusions and H, O, and S stable isotopic compositions of the deposit. The fluid-inclusion data indicate that aqueous fluid inclusions were trapped in chalcopyrite-bearing quartz veins in the gangue minerals. The homogenization temperatures range from 108°C to 299°C, and the salinities range from 0.5% to 11.8%, indicating medium to low temperatures and salinities. The trapping pressures range from 34.5 MPa to 56.8 MPa. The δ^（18）O_（H_2O） values and δD values of the fluid range from -6.94‰ to -5.33‰ and from -95.31‰ to -48.20‰, respectively. The H and O isotopic data indicate that the ore-forming fluid derived from a mix of magmatic water and meteoric water and that meteoric water played a significant role. The S isotopic composition of pyrite ranges from 1.9‰ to 5.2‰, with an average value of 3.1‰, and the S isotopic composition of chalcopyrite ranges from -0.9‰ to 4‰, with an average value of 1.36‰, implying that the S in the ore-forming materials was derived from the mantle. The introduction of meteoric water decreased the temperature, volatile content, and pressure, resulting in immiscibility. These factors may have been the major causes of the mineralization of the Hongshi copper deposit. Based on all the geologic and fluid characteristics, we conclude that the Hongshi copper deposit is an epithermal deposit.

Geochemical Tracing of Ore-forming Material Sources of Carlin-type Gold Deposits in the Yunnan-Guizhou-Guangxi Triangle Area --A Case Study of the Application of the Combined Silicon Isotopes Geochemistry and Siliceous Cathodoluminescence Analysis

Abstract This paper deals with characteristics of silicon isotope compositions and siliceous cathodoluminescence of host rocks, ores and hydrothermal silicified quartz of the Carlin-type ore deposits in the Yunnan-Guizhou-Guangxi triangle area. The study shows that primary silicified quartz is nonluminescent but quartz in host rocks and secondary silicified quartz are luminescent by the action of cathode rays. Correspondingly, silicon isotope compositions of host rocks, ores and hydro6thermal quartz veins are clearly distinguished. In strata from the Middle Triassic to the “Dachang” host bed, δ30Si of the host rocks ranges from 0.0% ?0.3%, while that of primary ore-forming silicified fluids from ?0.1% to ?0.4%; in the Upper Permian and Lower Carboniferous strata and Indosinian diabase host beds, δ30Si of the host rocks is from ?0.1% to ?0.2% and that of the primary silicified quartz veins from 0.3 % ?0.5 %. This pattern demonstrates the following geochemical mineralization process, primary ore-forming siliceous fluids migrated upwards quickly along the main passages of deep-seated faults from mantle to crust and entered secondary faults where gold deposits were eventually formed as a result of permeation and replacement of the siliceous ore-forming fluids into different ore-bearing strata. This gives important evidence for the fact that ore-forming fluids of this type of gold deposits were mainly derived from upper mantle differentiation and shows good prospects for deep gold deposits and geochemical background for large and superlarge gold deposits.

The Characteristics and Prospects of China's Assistance to Minority Areas in Realizing the Right to Development

Assisting minority areas to realize the right to development is an important part of Chinese government’s goals of protecting human rights and building a prosperous society. To assist minority areas to realize the right to development, China’s Constitution, laws, administrative regulations and policy documents define the State’s constitutional obligations. There also exists a legal and policy support system to help the minority areas to achieve economic and social development through measures such as transfer payments, assistance to Tibet and Xinjiang and counterpart support for poverty alleviation. However, China is also faced with the difficult challenges of poverty reduction, development, unbalanced regional development and other issues in assisting ethnic minority groups to realize the right to development.

Study on Prospects and Development Strategies of Ecotourism —A Case Study of Tongren Area,Guizhou Province of China

Environment and resources of Tongren area were introduced,it was proposed that Tongren was endowed with rich ecotourism resources and diversified landscape types,current conditions and development prospects of ecotourism resources were analyzed.Moreover,the study area has an excellent location and convenient traffic conditions,construction and development of local ecotourism has achieved remarkable progress as more efforts have been devoted in tourism industry.By cooperating with other regions,tourism brand of the study area as "Pure Land of Brahma,Peaceful World of Tongren" was built.Meanwhile,problems encountered by local ecotourism development were analyzed and development strategies proposed:competitive tour routes should be given on the basis of overall planning and balanced development,and tourism brands built;tourism traffic conditions should be improved and larger tourism development spaces constructed;tourism management and service level should be promoted,and tourism market expanded;propaganda and education about ecological protection should be enhanced,and eco-environment protection consciousness cultivated.This study was to provide useful references for the future ecotourism development of the local area.

Prediction of Hidden Granites in the Luziyuan Area of Yunnan Province and the Prospecting Direction

The Fe-Pb-Zn-Cu polymetallic deposits in the Luziyuan area, are of a sedimentary-reformed type related with magmatic hydrothermalism. Previous researches have suggested that the mineralization is closely related to the hidden granites, but little is known about these granites including their burial depth and scale, which has limited the establishment of prospecting models and the optimization of prospecting targets. Geophysical methods have a great exploration depth, and have played a unique role in the prediction of hidden granites. It is shown that granites have low density and high resistivity,

Geochemical studies of the Silurian oil reservoir in the Well Shun-9 prospect area, Tarim Basin, NW China

Commercial oil flow has been obtained from the sandstone reservoir of the Lower Silurian Kelpintag Formation in the Well Shun-9 prospect area.In the present studies,10 Silurian oil and oil sand samples from six wells in the area were analyzed for their molecular and carbon isotopic compositions,oil alteration（biodegradation）,oil source rock correlation and oil reservoir filling direction.All the Silurian oils and oil sands are characterized by low Pr/Ph and C21/C23 tricyclic terpane（〈1.0） ratios,＂V＂-pattern C27-C29 steranes distribution,low C28-sterane and triaromatic dinosterane abundances and light δ13C values,which can be correlated well with the carbonate source rock of the O3 l Lianglitage Formation.Different oil biodegradation levels have also been confirmed for the different oils/oil sands intervals.With the S1k2 seal,oils and oil sands from the S1k1 interval of the Kelpintag Formation have only suffered light biodegradation as confirmed by the presence of ＂UCM＂ and absence of 25-norhopanes,whereas the S1k3-1 oil sands were heavily biodegraded（proved by the presence of 25-norhopanes） due to the lack of the S1k2 seal,which suggests a significant role of the S1k2 seal in the protection of the Silurian oil reservoir.Based on the Ts/（Ts＋Tm） and 4-/1-MDBT ratios as reservoir filling tracers,a general oil filling direction from NW to SE has been also estimated for the Silurian oil reservoir in the Well Shun-9 prospect area.

Ore-forming and Exploration Models of the Baguamiao Gold Deposit,Shaanxi Province

The Baguamiao superlarge gold deposit in Shaanxi Province is one of the typical cases in China that are hosted by sedimentary rocks. Explorers and researchers have discussed the gold mineralization enrichment conditions by studying sulphur, oxygen, carbon, silicon stable isotopes and mineralizing fluid features of the Baguamiao gold deposit and proposed a hydrothermal sedimentation-magmatic reconstructing gold mineralization model featuring multi-sources of ore-forming materials and multistage mineralizations. In addition, prospecting for “Baguamiao-type” gold deposits was started in the Fengtai Basin and a great number of important prospecting targets such as Tonglinggou, Simaoling, Guoansi and Dachaigou were discovered.

METALLOGENIC REGULARITIES OF LARGE CONCEALED AND BLIND URANIUM DEPOSITS AND METALLOGENIC PROGNOSIS BY SYNTHETIC INFORMATION IN GRANITIC EXOCONTACT ZONES──Taking Eastern Hunan and Adjacent Areas as Examples

Under the guide of advanced theories of geosciences, new technology and methods of prospecting, integrating sedimentation, magmatic emplacement, metamorphism and deformation with mineralization by means of intersectional subjects, the author has revealed that the geodynamic setting of formation of uranium deposits of granitic exocontact zone type in eastern Hunan and neighbouring areas has a specia1 stretching strike-slip structure, a special thermal rock series,a special texture and composition of the crust and mantle, elaborated the macroscopic and microscopic features of stretching decollement faults in the Mingyuefeng area, and summed up the metallogenic regularities of typical uranium deposits, factors for a genetic mode1 and the criteria for prospecting by synthetic information, on the basis of which he has made prognosis of concealed and blind uranium deposits.

Discussion on the application prospect of the transient electromagnetic method based on the dual launcher and mine advanced detection

The dual transmitter implements the equivalent anti-magnetic flux transient electromagnetic method, which can effectively reduce the scope of the transient electromagnetic detection blind area. However, this method is rarely reported in the detection of pipelines in urban geophysical exploration and the application of coal mines. Based on this, this paper realizes the equivalent anti-magnetic flux transient electromagnetic method based on the dual launcher. The suppression effect of this method on the blind area is analyzed by physical simulation. And the detection experiment of underground pipelines is carried out outdoors. The results show that the dual launcher can significantly reduce the turn-off time, thereby effectively reducing the impact of the blind area on the detection results, and the pipeline detection results verify the device’s effectiveness. Finally, based on the ground experimental results, the application prospect of mine advanced detection is discussed. Compared with other detection fields, the formation of blind areas is mainly caused by the equipment. If the dual launcher can be used to reduce the blind area, the accuracy of advanced detection can be improved more effectively. The above research results are of great significance for improving the detection accuracy of the underground transient electromagnetic method.

老挝铜资源成矿规律与基于机器学习的远景预测

老挝处于特提斯成矿域南东段,具有丰富的矿产资源,但其地质工作基础薄弱,厘定矿产资源成矿规律并开展远景区预测是老挝在重点区实现找矿突破的有效途径。老挝1∶1000000国家尺度地球化学填图由中老双方合作完成,为其矿产资源和环境评价提供了高质量的地球化学基础数据和图件。本文主要利用国家尺度地球化学填图数据,结合老挝已发现矿产成矿规律,利用机器学习技术,开展铜资源远景区预测。研究结果表明:(1)老挝铜矿床的形成明显受到构造-岩浆-沉积作用控制,铜矿床主要类型有斑岩型、夕卡岩型、热液型和砂岩型。(2)老挝全国水系沉积物中铜含量为1.20~459.00μg/g,平均值为21.96μg/g,中位值为16.50μg/g,在7个三级大地构造单元中,长山地块和哀牢山—马江等3个缝合带的平均值高于其他几个构造单元,地球化学图显示铜在老挝分布不均匀,存在多个大面积分布的高背景区和异常区。(3)构建了包括单元素异常、矿化元素组合异常、指示中酸性岩体元素组合、控矿构造分布、碳酸盐岩和碎屑岩分布等要素的老挝铜矿多源信息定量信息预测模型。(4)利用随机森林成矿预测方法,共圈定9个成矿远景区,具有寻找斑岩型和夕卡岩型等类型铜矿找矿前景。

基于Prospect,Liberty和Geosail模型的森林叶面积指数的反演

针对传统的统计模型方法反演叶面积指数(LAI)具有不稳定、区域不统一性的缺点,本研究从物理机制角度出发,以Prospect,Liberty和Geosail模型为基础,建立查找表从TM影像上反演LAI,并与TRAC实测的LAI比较。结果表明:基于机制模型与查找表的方法反演的LAI与实测的LAI有较好的一致性,实测精度达到83.7%。

秘鲁铜元素地球化学空间分布及对成矿远景区的预测

秘鲁位于南美洲西岸,作为安第斯成矿带的重要组成部分,矿产资源丰富,铜矿资源储量和产量位居世界第二。本文首次对秘鲁开展全国范围全球尺度地球化学调查工作,获得汇水域沉积物样品共416件,秘鲁全境铜元素含量为2.38~495μg/g,背景值(中位数)为24.0μg/g。秘鲁全境、沿海带、安第斯山区和亚马孙平原的表层(深层)汇水域沉积物中铜元素平均含量依次为31.4(31.6)、45.6(32.2)、47.5(48.2)和21.3μg/g(24.9μg/g)。地球化学图显示,秘鲁铜空间分布整体呈现出西高东低的趋势,西部沿海带和中部安第斯山区含量较高,东部亚马孙平原区含量较低的特征。本文选用75%累积频率作为异常下限值,圈定出5处铜地球化学异常,其中两处达到地球化学巨省规模,两处达到地球化学域规模。同时,讨论铜地球化学异常的来源和影响因素,解析与之对应的矿产资源响应,秘鲁良好的构造演化环境,为大型、超大型铜矿床的形成提供有利条件。太平洋纳斯卡板块向南美大陆不断俯冲变换,致使洋壳发生部分熔融,产生强烈而广泛的中酸性岩浆活动,且岩浆中铜含量大规模富集,局部地区在特定环境下富集成矿。这一构造运动导致铜元素在秘鲁空间分布上呈现出多个地球化学块体,可能也是铜地球化学异常形成的原因之一。这些巨大的地球化学块体发现可用于未来寻找铜矿集区或大型、超大型铜矿床,圈定找矿远景区,并可以降低找矿风险,提高找矿效率,缩短找矿周期。研究圈定的地球化学找矿远景区,可为秘鲁铜矿勘查开发利用提供基础资料和数据。

巴基斯坦锂、铍地球化学分布特征与成矿远景区优选

锂、铍金属是世界战略性关键金属资源,在新材料和信息技术等新兴产业具有不可替代的重大用途。巴基斯坦位于欧亚、印度和阿拉伯三大板块汇聚部位,拥有优越的锂、铍成矿条件,但由于地质工作程度偏低,目前锂、铍金属资源潜力不明。低密度地球化学调查是研究锂、铍元素空间分布和快速圈定成矿远景区的有效方法。本文利用巴基斯坦1∶1000000低密度地球化学调查成果,阐述了巴基斯坦锂、铍元素地球化学背景,结合已有锂、铍矿床成矿地质背景分析,圈定了锂、铍成矿远景区,为锂、铍稀有金属找矿勘查提供依据。巴基斯坦全境基岩出露区水系沉积物中锂含量为1.56~118.20μg/g,平均值为20.06μg/g。铍含量为0.07~7.16μg/g,平均值为1.22μg/g。根据92%累频共圈定18个锂地球化学异常和12个铍地球化学异常,并优选找矿远景区。其中,喀喇昆仑地块和喜马拉雅造山带作为伟晶岩型锂矿的找矿远景区,查盖火山岩浆弧东作为盐湖卤水型锂矿的找矿远景区,喀喇昆仑地块是寻找伟晶岩型锂、铍矿床最有利的地区。

基于PROSPECT+SAIL模型反演叶面积指数的较强适用性植被指数的筛选

基于PROSPECT+SAIL植被辐射传输模型,通过控制不同的植被生化变量、地表参数和土壤光谱参数建立光谱数据集,定量地分析了归一化植被指数(NDVI)、比值植被指数(SR)、土壤调节植被指数(SAVI)等10种常用的植被指数(VIs)对叶面积指数(LAI)的响应.利用敏感性函数定量地筛选出具有较强适用性的转换型土壤调节植被指数(TSAVI).在此基础上,分别建立了TSAVI及常用植被指数NDVI反演LAI的模型.以张掖市南部地区的TM影像为数据源,进行了LAI的反演,并利用黑河生态水文遥感试验获得的中游LAI数据集对模型进行精度评价.结果表明:TSAVI–LAI模型最佳拟合关系为指数形式,其反演结果与LAI实测值的偏差最小(0.200),R2最大(0.686),RMSE最小(0.397).TSAVI可以作为较强适用性植被指数来进行LAI的反演.

粤港澳大湾区协同发展研究进展与展望

在国内外形势发生新变化、“一国两制”迈入新阶段等背景下,粤港澳大湾区协同发展成为研究热点。基于综合视角梳理大湾区协同发展研究进展可知:从多元化协同机制看,侧重自上而下的宏观协同机制研究,自下而上的微观协同机制研究有待深化;从多尺度协同模式看,内外尺度联动模式研究分析了内部协同结构及对外协同开放两方面,特殊功能区协同效应及与国内国际大市场联动效应研究有待深化,时空尺度演化模式研究揭示了传统发展模式转变态势及空间分异特征,有待从培育内生动力、推进空间均衡等方面开展对策分析;从多要素协同类型看,已开展人才、土地、基础设施等生产要素协同配置、现代产业协同发展及人地要素协同优化研究,生产要素跨境协同优化配置、相关产业规则衔接及人地关系多因素影响解析、跨尺度作用机制、系统性调控等研究有待深化。为促进新时代粤港澳大湾区协同发展,应重点从五方面深化既有研究:增强协同发展关键环节和路线图研究,解析大湾区高质量发展联动机制;强化跨境制度协同机制研究,加强大湾区整体协同及深港、琴澳等重点合作;重视自下而上的微观协同机制研究,聚焦民心相通、民生畅通、文化相联等重要抓手;聚焦融入双循环新发展格局战略需求,深化内外尺度联动模式系统性集成研究;统筹发展和安全,强化多要素韧性监测预警及协同调控研究。

糖尿病发病时间趋势及其与中国内脏脂肪指数的关系:一项前瞻性队列研究

背景糖尿病仍是全球重大公共卫生问题,横断面研究发现内脏脂肪与糖尿病患病密切相关,但糖尿病发病时间趋势及其与中国内脏脂肪指数(CVAI)关系的前瞻性队列研究较少。目的通过前瞻性队列研究分析上海市浦东新区居民糖尿病发病时间趋势及其与CVAI的关系,为其科学防治提供依据。方法本研究为前瞻性队列研究。选取2013年1—7月参与浦东新区慢性病危险因素监测项目的12个乡镇街道的35个村、居委的居民5236人为研究队列。收集其基线资料,内容包括CVAI、内脏脂肪指数(VAI)、BMI、腰围(WC)、腰臀比(WHR)、腰高比(WHtR)、身体形态指数(ABSI)和身体肥胖指数(BAI),分别于2016年和2019年进行追踪随访;截至随访结束(2019年10月),通过问卷调查、实验室检查、医疗系统就诊信息和生命统计信息系统判断该研究队列糖尿病新发情况。依据基线CVAI、VAI、BMI、WC、WHR、WHtR、ABSI、BAI四分位数将纳入人群分别分为第Q1~Q4四分位数:CVAI各组人数依次为1306、1307、1307、1307人;VAI各组人数依次为1300、1316、1306、1306例;BMI各组人数依次为1305、1302、1312、1311人;WC各组人数依次为1302、1273、1287、1367人;WHR各组人数依次为1180、1203、1332、1514人;WHtR各组人数依次为1199、1393、1400、1237人;ABSI各组人数依次为1316、1302、1302、1308人;BAI各组人数依次为1310、1304、1308、1307人。采用多因素Cox回归分析CVAI和其他肥胖指标与糖尿病发病的关系;采用受试者工作特征曲线(ROC曲线)比较CVAI与其他肥胖指标的预测作用。结果浦东新区居民2013—2016年糖尿病发病密度为33.55/1000人年,2017—2019年糖尿病发病密度为23.25/1000人年,随着年龄的增长,糖尿病总发病密度呈现出升高趋势(2013—2016年:χ^(2)=28.503,P_(趋势)<0.001;2017—2019年:χ^(2)=25.600,P_(趋势)<0.001)。截至2016年,基线CVAI四分位数越高,糖尿病累积发病率(CVAI:χ^(2)=131.865,P_(趋势)<0.001)和发病密度(CVAI:χ^(2)=100.105,P_(趋势)<0.001)均越高。调整相关混杂因素后的多因素Cox回归分析结果显示,与CVAI处于Q1相比,CVAI处于Q4的男性糖尿病的发病风险增加79.4%(HR=1.794,95%CI=1.044~3.083,P<0.05),女性糖尿病的发病风险增加371.2%(HR=4.712,95%CI=2.601~8.538,P<0.05)。ROC曲线结果显示,在预测男性糖尿病发病情况中,CVAI对男性糖尿病预测的ROC曲线下面积(AUC)为0.600(95%CI=0.561~0.640),识别男性糖尿病的约登指数为0.181,截断值为104.118;Delong检验结果显示,CVAI对女性糖尿病预测的准确性最高(AUC=0.699),且在识别女性糖尿病时有最大的约登指数值0.317,最佳截断值为104.609。结论2013—2019年上海市浦东新区居民糖尿病发病密度随年龄的增长呈升高趋势;且相较于其他肥胖指标,CVAI可作为预测糖尿病发病风险的指标。

摩洛哥大阿特拉斯构造带东段铅、锌地球化学分布与找矿远景区优选

摩洛哥大阿特拉斯构造带位于特提斯成矿域西端,成矿地质条件优越,已发现大量MVT型铅锌矿床(点),但长久以来较低的地质工作程度使得铅锌成矿潜力不明。中大比例尺地球化学调查是资源勘查的有效手段,准确的地球化学异常信息能快速圈定找矿远景区,提高勘查效率和成功率。本文通过摩洛哥大阿特拉斯构造带东段万余平方千米区域的1∶100000地球化学调查,查明该区水系沉积物中铅元素含量为5.7~43 210.0μg/g,平均含量为45.0μg/g;锌元素含量为12.2~75 420.0μg/g,平均含量为86.4μg/g,均高于地壳克拉克值。以92%累频为异常下限(Pb含量为36.9μg/g, Zn含量为78.3μg/g)共圈定73个铅地球化学异常和68个锌地球化学异常,通过铅、锌等元素的地球化学分布特征,结合区域地质背景和成矿条件分析,划出了3个主要铅锌成矿带,成矿带内进一步圈定了9处铅锌矿找矿远景区,提出该区具有寻找MVT型铅锌矿的潜力。该成果为下一步开展找矿勘查提供了重要方向。

Genesis, metallogenic model, and prospecting prediction of the Nibao gold deposit in the Guizhou Province, China

Southwestern Guizhou province is one of China’s most important distribution areas of Carlin-type gold deposits. The Nibao deposit is a typical gold deposit in southwestern Guizhou. To elucidate the genesis of the Nibao gold deposit, establish a metallogenic model, and guide prospecting prediction, we systematically collected previously reported geological, geochemical, and dating data and discussed the genesis of the Nibao gold deposit,based on which we proposed the metallogenic model.Earlier works show that the Nibao anticline, F1 fault, and its hanging wall dragged anticline(Erlongqiangbao anticline) were formed before or simultaneously with gold mineralization, while F2, F3, and F4 faults postdate gold mineralization. Regional geophysical data showed extensive low resistivity anomaly areas near the SBT(the product of tectonic slippage and hydrothermal alteration)between the P2/P3 and the strata of the Longtan Formation in the SSE direction of Nibao anticline in the lower plate of F1 and hanging wall dragged anticline(Erlongqiangbao anticline), and the anomaly areas are distributed within the influence range of anticlines. Simultaneously, soil and structural geochemistry show that F1, Nibao anticline,Erlongqiangbao anticline, and their transition areas all show good metallogenic elements(Au, As, and S) assemblage anomalies, with good metallogenic space and prospecting possibilities. There are five main hypotheses about the source of ore-forming fluids and Au in the Nibao gold deposit:(1) related to the Emeishan mantle plume activity;(2) source from the Emeishan basalt;(3) metamorphic fluid mineralization;(4) basin fluid mineralization;(5) related to deep concealed magmatic rocks;of these, the mainstream understanding is the fifth speculation. It is acknowledged that the ore-forming fluids are hydrothermal fluids with medium–low temperature, high pressure, medium–low salinity, low density, low oxygen fugacity, weak acidity, weak reduction, and rich in CO_(2)and CH_(4). The fluid pressure is 2–96.54 MPa, corresponding to depths of 0.23–3.64 km. The dating results show that the metallogenic age is ~141 Ma, the extensional tectonic environment related to the westward subduction of the Pacific Plate. Based on the above explanation, the genetic model related to deep concealed magmatic rocks of the Nibao gold deposit is established, and favorable prospecting areas are outlined;this is of great significance for regional mineral exploration and studying the genesis of gold deposits.