Quantitative analysis of intrusive body morphology and its relationship with skarn mineralization——A case study of Fenghuangshan copper deposit, Tongling, Anhui, China

The shapes of intrusive body and contact zone might influence the formation and distribution of orebodies in skarn deposit.By taking Xinwuli intrusive body in Fenghuangshan copper deposit,Tongling,Anhui,China,as the research object,a new method was used to obtain the quantitative relationship between intrusion morphology and skarn mineralization.The first step of the method was to extract morphological characteristic parameters based on mathematical morphology and Euclidean distance transformation;then the quantitative relationship between the parameters and orebodies was analyzed;finally correlational analyses between the parameters and mineralization indices were conducted.The results show that morphological characteristic parameters can effectively indicate the location of concealed ore bodies in skarn deposit,with the following parts as advantageous positions of skarn mineralization:(1)the parts away from the1st trend surface in the range from?25to50m;(2)the convex parts about200m away from the2nd trend surface,around which the tangent plane of the intrusive body is approximately consistent with the trend surface;(3)the contact zones with angle between intrusive body original contact surface and trend contact surface ranging from35°to70°;(4)the parts with angle between intrusive body original contact surface and regional extruding far crustal stress ranging from50°to60°.These knowledge can be applied to more skarn deposits for future mineral exploration.

Effect of temperature on leaching behavior of copper minerals with different occurrence states in complex copper oxide ores

The effect of temperature on leaching behavior of copper minerals with different occurrence states in complex copper oxide ores was carried out by phase analysis means of XRD, optical microscopy and SEM-EDS. The results indicated that at ambient temperature, the easily leached copper oxide minerals were completely dissolved, while the bonded copper minerals were insoluble. At lukewarm temperature of 40℃, it was mainly the dissolution of copper in isomorphism state. With increasing temperature to 60℃, the copper leaching rate in the adsorbed state was significantly accelerated. In addition, when the temperature increased to 80℃, the isomorphic copper was completely leached, leaving 11.2% adsorbed copper un-leached. However, the copper in feldspar-quartz-copper-iron colloid state was not dissolved throughout the leaching process. Overall, the leaching rates of copper in different copper minerals decreased in the order: malachite, pseudo-malachite > chrysocolla > copper-bearing chlorite > copper-bearing muscovite > copper-bearing biotite > copper-bearing limonite > feldspar-quartz-copper-iron colloid.

Geology and mineralization of the Pulang supergiant porphyry copper deposit(5.11 Mt)in Shangri-la,Yunnan Province,China:A review

The porphyry copper belt in the Geza island arc in southwestern China is the only Indosinian porphyry copper metallogenic belt that has been discovered and evaluated so far.The Pulang porphyry copper deposit(also referred to as the Pulang deposit)in this area has proven copper reserves of 5.11×106 t.This deposit has been exploited on a large scale using advanced mining methods,exhibiting substantial economic benefit.Based on many research results of previous researchers and the authors’team,this study proposed the following key insights.(1)The Geza island arc was once regarded as an immature island arc with only andesites and quartz diorite porphyrites occurring.This understanding was overturned in this study.Acidic endmember components such as quartz monzonite porphyries and quartz monzonite porphyries have been identified in the Geza island arc,and the mineralization is mainly related to the magmatism of quartz monzonite porphyries.(2)Complete porphyry orebodies and large vein orebodies have developed in the Pulang deposit.Main orebody KT1 occurs in the transition area between the potassium silicate alteration zone of quartz monzonite porphyries and the sericite-quartz alteration zone.Most of them have developed in the potassium silicate alteration zone.The main orebody occurs as large lenses at the top of the hanging wall of rock bodies,with an engineering-controlled length of 1920 m and thickness of 32.5‒630.29 m(average:187.07 m).It has a copper grade of 0.21%-1.56%(average:0.42%)and proven copper resources of 5.11×10^(6) t,which are associated with 113 t of gold,1459 t of silver,and 170×10^(3) t of molybdenum.(3)Many studies on diagenetic and metallogenic chronology,isotopes,and fluid inclusions have been carried out for the Pulang deposit,including K-Ar/Ar-Ar dating of monominerals(e.g.,potassium feldspars,biotites,and amphiboles),zircon U-Pb dating,and molybdenite Re-Os dating.The results show that the porphyries in the Pulang deposit are composite plutons and can be classified into pre-mineralization quartz diorite porphyrites,quartz monzonite porphyries formed during the mineralization,and post-mineralization granite porphyries,which were formed at 223±3.7 Ma,218±4 Ma,and 207±3.9 Ma,respectively.The metallogenic age of the Pulang deposit is 213‒216 Ma.(4)The petrogeochemical characteristics show that the Pulang deposit has the characteristics of volcanic arc granites.The calculation results of trace element contents in zircons show that quartz monzonite porphyries and granite porphyries have higher oxygen fugacity.The isotopic tracing results show that the diagenetic and metallogenic materials were derived from mixed crust-and mantle-derived magmas.

Ore Minerals and Genesis of Lala Copper Deposit,Sichuan Province

The Lala Cu deposit in Sichuan Province is one of the most important large deposits in SW China,both in terms of Cu and associated Au-Mo-Co-REE-Fe. Systematic ore petrology study shows that ore minerals are mainly composed of hydrothermal magnetite,chalcopyrite and molybdenite.The wall-rock alterations include biotitization,silicification, carbonatation,albitization,potash feldspathization, apatitation,actinolitation and fluoritation,et al. The Pyrite and magnetite have euhedral-subhedral crystalline grained texture and the chalcopyrite

Geology and mineralization of the Tiegelongnan supergiant porphyry-epithermal Cu(Au, Ag) deposit(10 Mt) in western Tibet, China: A review

The Tiegelongnan Cu(Au,Ag)deposit in central Tibet contains more than 10 Mt of copper ranking 29 th in the world.It is characterized by typical porphyry-epithermal alteration and mineralization.In order to improve the understanding of porphyry-epithermal copper deposit in Tibet,new zircon U-Pb age and sulfur isotope data along with published data in the Tiegelongnan are presented to investigate the formation and preservation mechanism.Ore-related intrusive rocks in the Tiegelongnan including Early Cretaceous(about 120 Ma)granodiorite porphyry and diorite porphyry are closely related to the northward subduction of Bangongco-Nujiang ocean.Sulfur mainly comes from deep magma,and ore-forming fluid is affected by both magmatic and meteoric water.The metallogenic setting of Tiegelongnan is consistent with those of Andean porphyry copper deposits in South America.The cover of the Meiriqiecuo Formation volcanic rocks,Lhasa-Qiangtang collision and India-Eurasian collision have significance in the preservation and uplift of the deposit.The formation,preservation and discovery of Tiegelongnan play an important role in exploration of ancient porphyry-epithermal deposits in Tibet.

Metallogenic Epoch and Ore-forming Environment of the Lamasu Skarn-porphyritic Cu-Zn deposit,western Tianshan,Xinjiang,NW China

Granitic rocks, widely developed in the Lamasu copper ore region, western Tianshan were formed at 390.5±7.7 Ma according to the SHRIMP zircon U-Pb dating of the plagioclase granite porphyry. Based on the regional tectonic evolution and published chronological data of both diagenesis and mineralization, the Biezhentao- Kokirqin region was rolled into the orogen associated with the closure of Yili Ocean during early Devonian. The N-S-trending thrust faults were formed during this period and accompanied by the intrusion of granitic rocks. On this stage, the paleo-Asian Ocean Plate entered into the early collision orogenic phase and the plagioclase granite porphyry intruded （390.5±7.7 Ma） and replaced with limestone of the Mesoproterozoic Kusongmuqieke Group, Jixianian System and formed the early phase of skarn-type copper mineralization in the Lamasu region. Furthermore, the subduction-melting of Bayingou Ocean Plate during Carboniferous generated a deep-seated magmatic chamber in the Lamasu copper ore region which located in the northwestern part of the Paleozoic Biezhentao-Kokirqin island arc. The magmatic chamber segregated Cu-bearing magmas, which transported upward to the shallow earth crust along the faults or fractures and formed the Cu-hosting porphyry. According to the research on the characteristics of the ore deposit and the ore-forming environment as mentioned above, the Lamasu Cu-Zn deposit was characterized by the superposing of mineralization at different geological settings and it was skarn-porphyritic type.

Geology,Fluid Inclusion and Isotopic Study of the Neoproterozoic Suoi Thau Copper Deposit,Northwest Vietnam

The Sin Quyen-Lung Po district is an important Cu metallogenic province in Vietnam, but there are few temporal and genetic constraints on deposits from this belt. Suoi Thau is one of the representative Cu deposits associated with granitic intrusion. The deposit consists of ore bodies in altered granite or along the contact zone between granite and Proterozoic meta-sedimentary rocks. The Cu-bearing intrusion is sub-alkaline I-type granite. It has a zircon U-Pb age of ~776 Ma, and has subduction-related geochemical signatures. Geochemical analysis reveals that the intrusion may be formed by melting of mafic lower crust in a subduction regime. Three stages of alteration and mineralization are identified in the Suoi Thau deposit, i.e., potassic alteration; silicification and Cu mineralization; and phyllic alteration. Two-phase aqueous fluid inclusions in quartz from silicification stage show wide ranges of homogenization temperatures （140-383℃） and salinities （4.18wt%- 19.13wt%）. The high temperature and high salinity natures of some inclusions are consistent with a magmatic derivation of the fluids, which is also supported by the H-O-S isotopes. Fluids in quartz have JD values of-41.9‰ to -68.8%. The fluids in isotopic equilibrium with quartz have j180 values ranging from 7.9‰ to 9.2%. These values are just plotted in the compositional field of magmatie- hydrothermal fluids in the ~Dwater versus jlSOwater diagram. Sulfide minerals have relatively uniform j34S values from 1.84%o to 3.57%0, which is supportive of a magmatic derivation of sulfur. The fluid inclusions with relatively low temperatures and salinities most probably represent variably cooled magmatic-hydrothermal fluids. The magmatic derivation of fluids and the close spatial relationship between Cu ore bodies and intrusion suggest that the Cu mineralization most likely had a genetic association with granite. The Suoi Thau deposit, together with other deposits in the region, may define a Neoproterozoic subduction-related ore-forming belt.

Forecast of blind ore body in Zhangcaigou area around Wulaga gold deposit

By the study of metallogenetic conditions and ore-controlling factors, the metallogenetic indicators in geology, geochemistry and geophysics about Wulaga gold deposit have been obtained. Using the indicators the blind ore bodies have been forecasted in Zhangcaigou area. By drilling check, a gold-bearing ore body with 3 m thickness in an average tenor of 20.4×10 -6 at the depth of 70 m has been found in the forecast area. It shows that the forecast method should be effective.

Geological characteristics and mineralization setting of the Zhuxi tungsten(copper) polymetallic deposit in the Eastern Jiangnan Orogen

The Zhuxi ore deposit is a super-large scheelite(copper) polymetallic deposit discovered in recent years. It grew above copper/tungsten-rich Neoproterozoic argilloarenaceous basement rocks and was formed in the contact zone between Yanshanian granites and Carboniferous-Permian limestone. Granites related to this mineralization mainly include equigranular, middle- to coarse-grained granites and granitic porphyries. There are two mineralization types: skarn scheelite(copper) and granite scheelite mineralization. The former is large scale and has a high content of scheelite, whereas the latter is small scale and has a low content of scheelite. In the Taqian-Fuchun Basin, its NW boundary is a thrust fault, and the SE boundary is an angular unconformity with Proterozoic basement. In Carboniferous-Permian rock assemblages, the tungsten and copper contents in the limestone are both very high. The contents of major elements in granitoids do not differ largely between the periphery and the inside of the Zhuxi ore deposit. In both areas, the values of the aluminum saturation index are A/CNK>1.1, and the rocks are classified as potassium-rich strongly peraluminous granites. In terms of trace elements, compared to granites on the periphery of the Zhuxi ore deposit, the granites inside the Zhuxi ore deposit have smaller d Eu values, exhibit a significantly more negative Eu anomaly, are richer in Rb, U, Ta, Pb and Hf, and are more depleted in Ba, Ce, Sr, La and Ti, which indicates that they are highly differentiated S-type granites with a high degree of evolution. Under the influence of fluids, mineralization of sulfides is evident within massive rock formations inside the Zhuxi ore deposit, and the mean SO_3 content is 0.2%. Compared to peripheral rocks, the d Eu and total rare earth element(REE) content of granites inside the Zhuxi ore deposit are both lower, indicating a certain evolutionary inheritance relationship between the granites on the periphery and the granites inside the Zhuxi ore deposit. For peripheral and ore district plutons, U-Pb zircon dating shows an age range of 152–148 Ma. In situ Lu-Hf isotope analysis of zircon in the granites reveals that the calculated e_(Hf)(t) values are all negative, and the majority range from -6 to -9. The T_(DM2) values are concentrated in the range of 1.50–1.88 Ga(peak at 1.75 Ga), suggesting that the granitic magmas are derived from partial melting of ancient crust. This paper also discusses the metallogenic conditions and ore-controlling conditions of the ore district from the perspectives of mineral contents, hydrothermal alteration, and ore-controlling structures in the strata and the ore-bearing rocks. It is proposed that the Zhuxi ore deposit went through a multistage evolution, including oblique intrusion of granitic magmas, skarn mineralization, cooling and alteration, and precipitation of metal sulfides. The mineralization pattern can be summarized as "copper in the east and tungsten in the west, copper at shallow-middle depths and tungsten at deep depths, tungsten in the early stage and copper in the late stage".

同构造隐伏花岗岩体及其热液成矿系统——以河南省熊耳山铁炉坪银多金属矿田为例

以位于华北克拉通南缘的河南省熊耳山铁炉坪银多金属矿田为研究对象,通过对区内地质构造、成矿作用、物化探资料、遥感影像等综合研究,发现该矿田是一个与同构造隐伏花岗岩体有关的岩浆热液成矿系统。推测该隐伏岩体为一个东宽西窄、东厚西薄的“鞋底”状花岗质岩席,其总体空间形态与熊耳山变质核杂岩下盘的东向运动学方向密切相关。高位岩浆房的主体(隐伏岩体厚大部分)定位于故县水库以东地带。区内已发现的银、金多金属矿床主要是隐伏岩体东部主体顶上带外缘区定位的中温热液脉状矿化。推测在隐伏岩体顶上带的中南部还有三个隐伏岩钟发育部位,正是岩浆热液二次沸腾核心区域,因而是形成高温的斑岩型铜钼矿或隐爆角砾岩型钼金矿的最有利区段。

内蒙古额勒根斑岩型钼(铜)矿化区辉钼矿铼-锇同位素年龄及地质意义

为了查明额勒根矿化区斑岩型钼(铜)矿化发生的时间,对主要矿化体内5件辉钼矿样品进行了铼_锇同位素分析,所获同位素等时线年龄为(332.0±9.0)Ma(2σ),其MSWD值为0.29。鉴于辉钼矿呈浸染状分布于似斑状花岗闪长岩和花岗闪长斑岩体中,并且与黄铜矿和黄铁矿呈共生结构关系,推测额勒根地区斑岩型钼(铜)矿化体、似斑状花岗闪长岩和花岗闪长斑岩体的形成时间为早石炭世中期,均是海西中期构造_岩浆活动的产物。

黑龙江省东宁县金厂金矿床角砾型铜金矿体流体包裹体研究

金厂金矿床是中国东部陆缘超大型热液金矿床之一,矿床主要由角砾型金矿体和铜金矿体构成。为研究2种矿体的成矿流体来源、演化之间的联系,对铜金矿体中石英等矿物的流体包裹体进行了岩相学、显微测温和单个包裹体气液相成分激光拉曼探针分析。研究表明：①流体包裹体类型有纯气相包裹体、气液两相（包括富气相）包裹体、含子矿物多相包裹体和纯液相包裹体;②均一温度变化范围在230-600℃（〉600℃）之间,其中,钾长石-石英-黄铁矿阶段、石英-黄铁矿阶段、石英-多金属硫化物阶段的温度分别为510-600℃、410-510℃、270-410℃;③盐度w（NaCleq）变化在2.57%-73.96%之间,可分为高温高盐度（35.99%-73.96%）、高温中高盐度（38.94%-57.09%）和高中温中低盐度（2.57%-19.05%）3类;④流体包裹体气相成分主要为H2O、CO2,少量N2、C4H6、H2;⑤多相流体包裹体中的子矿物有石盐、钾盐、石膏、重晶石和黄铜矿等。这些特征揭示成矿流体为高氧化岩浆热液（H2O-CO2-NaCl-SO4^2-型）。结合前人对角砾岩型金矿体（1号）的流体包裹体研究,初步确定成矿流体的演化过程为,来自幔源岩浆期后的热流体,上升到达地壳浅部发生隐爆、沸腾作用,形成低盐度和高盐度含矿流体后,伴随着温度和压力的降低,流体结晶沉淀,形成角砾岩型铜金矿体。

吉林二密复式火山机构及成矿控制作用

以松顶山为中心的二密复式火山机构,受东西向基底断裂与近南北向壳断裂叠加部位控制。中心(松顶山一带)为先期闪长质次火山岩侵入,闪长质岩体边缘接触带附近发育寄生火山口(次一级),并充填花岗质次火山小岩株,构成破火山机构环状构造(内环)。二密铜金矿床各矿段主要铜矿体集中于花岗质岩体内及其附近,总体分布和方向又受接触带构造控制。结合区域成矿规律,通过成岩成矿关系研究表明,本矿床除铜矿外,还具有金的找矿前景,并给出了该矿床的成矿模式。

玉龙铜矿Ⅴ号矿体氧化矿石工艺矿物学特征

为了给回收西藏玉龙铜矿Ⅴ号矿体氧化矿石中的铜提供基础依据,采用化学分析、物相分析、光学显微镜分析、扫描电镜及能谱分析等手段对该矿石进行了工艺矿物学研究。结果表明,该矿石具有"一杂三高一细"即"铜赋存形式复杂","褐铁矿含量高"、"易泥化脉石和易浮方解石含量高"、"黄铁矿含量高","有用矿物嵌布粒度极细"的特点,属于极难处理矿石。因此,要较好地利用该铜矿资源,须采用选冶联合工艺,并在工艺过程中采取细磨、消除褐铁矿及其他干扰矿物的影响等针对性措施。

赣北城门山铜矿床Ⅰ号矿体矿化富集规律及找矿方向研究

城门山铜矿是我国著名的大型铜矿,通过总结矿区主要铜多金属矿体之一的Ⅰ号矿体成矿地质条件、矿体地质特征、矿化富集规律及金属分带,并以此研究Ⅰ号矿体的元素分带性成因,成矿元素的差异性,并从矿体在走向上、倾向上的差异,结合矿体在厚度和品位差异成因,总结成矿作用的异同点,分析Ⅰ号矿体根据成矿温度以及金属元素成矿分带性,矿体沿走向东、西端延伸变化,两端均有较好的找矿空间范围,但东段优于西段,探讨矿区外围的找矿方向。

论地洼型砂岩铜、银矿床的成矿模式

分析了构造、储矿砂体、地下水活动三个相关地质因素对砂岩铜、银矿床的控制作用，从而建立了以地下水活动为主导的地洼型砂岩铜、银成矿模式。根据构造和矿体特征，将其划分为两个亚模式-褶皱控制模式和断裂控制模式，并阐明了该模式的意义，及其在找矿中的指导作用。

勘查区找矿预测理论与方法及其应用案例

降低勘查风险、实现科学找矿一直是国内外矿产勘查界不断探索的前缘领域和研究热点,而勘查区找矿预测理论与方法是解决这一难题的有效途径。该方法将成矿作用内因(元素的地球化学特征)和外因(地质作用类型)相结合,构建以成矿地质体、成矿构造与成矿结构面和成矿作用特征标志为主要内容的找矿预测地质模型,通过大比例尺构造蚀变填图、物化探测量和专题研究等综合方法,预测推断矿体赋存位置,最后通过工程施工,发现并查明工业矿体(矿床)。依据勘查区找矿预测理论与方法,在四川拉拉铜矿、新疆玛尔坎苏锰矿带穆呼-玛尔坎土锰矿及内蒙古大兴安岭南段敖脑达坝地区锡多金属矿开展找矿预测,取得了较好效果。

银山铜铅锌矿九区北山区深部矿床地质特征

为指导银山矿田其它四个区段深部找矿,通过地质学和同位素年代学的分析方法,总结了银山铜铅锌矿九区北山区深部矿床特征,该矿床是银山背斜格架下的中生代陆相火山-次火山岩浆期后中低温热液矿床。此次九区北山区深部详查成果是银山矿田深部延伸新增资源储量,探明122b+332+333矿石量7 232.73万t,主矿产铜金属量52.70万t、共生铅8.79万t、共生锌16.74万t、伴生金41.72 t、伴生银1 026.09 t、伴生硫470.77万t。银山矿田其它四个区段深部和九区北山区-1 200 m标高以下仍有极好的找矿前景,同时也丰富了人们对"银山式铜铅锌多金属矿床"成矿地质特征的认识。

九顶山铜钼多金属矿区岩浆侵入期次和成矿作用

通过对九顶山铜钼矿区复式斑岩体特征、矿化特征、成矿作用之间关系的研究,初步将九顶山斑岩体岩浆活动可分为3期:第一期为正长斑岩、石英正长斑岩;第二期为斑状花岗岩与煌斑岩(a)组合;第三期为花岗斑岩与煌斑岩(b)组合;其中第一、二期与矿化关系密切。按照容矿围岩可分为斑岩型矿石、矽卡岩型矿石、角岩型矿石和煌斑岩型矿石4类;按成矿元素组合可分为钼矿、钼铜矿、铜矿、磁铁矿、金矿等类型;铜、钼矿化与石英钾长石化带和石英绢云母化带关系密切。

金川铜镍矿床I矿区地质体三维建模与矿化空间分析

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