Muscovite 40Ar-39Ar age and its geological significance in Zhuxi W（Cu） deposit, northeastern Jiangxi

The Zhuxi W(Cu)skarn deposit,the world’s largest tungsten deposit is newly discovered in Jingdezhen city,northeastern Jiangxi province,China.It mainly occurs near the contact zone between the Yanshanian granites and the Late Paleozoic carbonate rocks.Three types of mineralization including skarn type,altered granite type and quartz vein veinlet type orebodies have been observed.In this study,the 40Ar 39Ar age of hydrothermal muscovite coexisting with copper mineralization in the altered granite type orebody formed near the unconformity interface is determined by step-heating technology using CO2 laser.The plateau age,isochron age,and inverse isochron age of muscovite are(147.39±0.94)Ma,(147.2±1.5)Ma,and(147.1±1.5)Ma,respectively.These ages are almost identical to the ages of ore-related granite and other mineralization types in the Zhuxi W(Cu)deposit,indicating that the Cu mineralizations occurred at the shallow depth and near the unconformity interface are contemporaneous during the Late Jurassic.This further suggested that the acompanied W and Cu mineralization in the Zhuxi W(Cu)deposit which may be controlled by the magma source is enriched in both W and Cu.

An ethnobotanical study of forage plants in Zhuxi County in the Qinba mountainous area of central China

In the Qinba mountainous area of Central China,pig farming has a significant impact on the growth of the rural economy and has substantially increased farmer incomes.Traditional knowledge plays an important role in the selection of forage plant species for pig farming by local people.This study aimed to identify the forage plants used for pig feeding and to catalog indigenous knowledge regarding their use.During 2016 and 2017,ethnobotanical surveys and inventories were conducted in Zhuxi County,Hubei Province,China.Data were collected using semi-structured interviews,key informant reports,free listings,guided field walks,and participatory observations with 77 households in 16 villages in 13 towns/townships.The obtained data were analyzed using a relative frequency citation(RFC)index.Overall,145 wild forage plants from 91 genera and 31 families were recorded.The most cited families were Asteraceae,Polygonaceae,Urticaceae,Amaranthaceae,Fabaceae,Cruciferae,Caryophyllaceae,and Lamiaceae.Whole plants(75.9%)and tender leaves(12.4%)were the most frequently used parts of the plants.Most of the forage plants were herbaceous(88.9%).Almost all forage plants could be collected throughout the year(62.7%).Raw and cooked were the two main preparation methods.The most frequently cited species were Taraxacum mongolicum,Bidens pilosa,Sonchus oleraceus,Pilea verrucosa,and Pilea pumila var.obtusifolia.A total of 14 species were identified as the top forage plants in Zhuxi County based on their RFC values(RFC value greater than 0.5).Local people possess rich traditional knowledge about the utilization and management of forage plants for pig feeding.However,the maintenance of this traditional knowledge may be seriously threatened by changes in pig feeding modes and the lack of successors.Appropriate strategies and action plans have been suggested for the conservation of traditional knowledge associated with biodiversity and the sustainable use of forage species resources.These include 1)taking targeted measures to protect forage resources and associated traditional knowledge;2)strengthening research on the forage plants with the highest RFC values for nutritional value,digestibility,other functions,and ecological status;and 3)enhancing the identification of poisonous forage plants.

Evolution of the magmatic–hydrothermal system and formation of the giant Zhuxi W–Cu deposit in South China

The Zhuxi deposit is a recently discovered W–Cu deposit located in the Jiangnan porphyry–skarn W belt in South China. The deposit has a resource of 3.44 million tonnes of WO3, making it the largest on Earth,however its origin and the evolution of its magmatic–hydrothermal system remain unclear, largely because alteration–mineralization types in this giant deposit have been less well-studied, apart from a study of the calcic skarn orebodies. The different types of mineralization can be classified into magnesian skarn, calcic skarn, and scheelite–quartz–muscovite(SQM) vein types. Field investigations and mineralogical analyses show that the magnesian skarn hosted by dolomitic limestone is characterized by garnet of the grossular–pyralspite(pyrope, almandine, and spessartine) series, diopside, serpentine,and Mg-rich chlorite. The calcic skarn hosted by limestone is characterized by garnet of the grossular–andradite series, hedenbergite, wollastonite, epidote, and Fe-rich chlorite. The SQM veins host highgrade W–Cu mineralization and have overprinted the magnesian and calcic skarn orebodies. Scheelite is intergrown with hydrous silicates in the retrograde skarn, or occurs with quartz, chalcopyrite, sulfide minerals, fluorite, and muscovite in the SQM veins.Fluid inclusion investigations of the gangue and ore minerals revealed the evolution of the ore-forming fluids, which involved:(1) melt and coexisting high–moderate-salinity, high-temperature, high-pressure(>450 ℃and >1.68 kbar), methane-bearing aqueous fluids that were trapped in prograde skarn minerals;(2) moderate–low-salinity, moderate-temperature, moderate-pressure(~210–300 ℃and ~0.64 kbar),methane-rich aqueous fluids that formed the retrograde skarn-type W orebodies;(3) low-salinity,moderate–low-temperature, moderate-pressure(~150–240 ℃and ~0.56 kbar), methane-rich aqueous fluids that formed the quartz–sulfide Cu(–W) orebodies in skarn;(4) moderate–low-salinity,moderate-temperature, low-pressure(~150–250 ℃and ~0.34 kbar) alkanes-dominated aqueous fluids in the SQM vein stage, which led to the formation of high-grade W–Cu orebodies. The S–Pb isotopic compositions of the sulfides suggest that the ore-forming materials were mainly derived from magma generated by crustal anatexis, with minor addition of a mantle component. The H–O isotopic compositions of quartz and scheelite indicate that the ore-forming fluids originated mainly from magmatic water with later addition of meteoric water. The C–O isotopic compositions of calcite indicate that the ore-forming fluid was originally derived from granitic magma, and then mixed with reduced fluid exsolved from local carbonate strata. Depressurization and resultant fluid boiling were key to precipitation of W in the retrograde skarn stage. Mixing of residual fluid with meteoric water led to a decrease in fluid salinity and Cu(–W) mineralization in the quartz–sulfide stage in skarn. The high-grade W–Cu mineralization in the SQM veins formed by multiple mechanisms, including fracturing, and fluid immiscibility, boiling, and mixing.

The Relationship between Forestland Soil Fertility and Gathering Firewood in the Zhuxi Watershed in the Red Soil Hilly Region of China

Declining soil fertility has become an increasingly urgent problem and gathering firewood is one of the important contributing factors.Due to the excessive exploitation of natural resources especially for firewood,the red soil hilly region has become one of the most vulnerable eco-environment regions in China.The pressure of gathering firewood on forestland soil fertility in forestland has been generally estimated by geographical information system and questionnaire method in this paper in the Zhuxi watershed of Changting County,Fujian Province,China,a typical representative in the red soil hilly region of China.The results of this study show that：i） Forestland soil fertility is negatively affected by gathering firewood,which is more intensive in the integrated buffer zone than out of zone.The forestland soil fertility grade,OM,total N,available N,total P,available P,total K,available K,pH and ＆lt;2μm clay content are lower and bulk density is higher in the integrated buffer zone than those out.ii） The forestland soil fertility grade,OM,total N,available N,total P,available P,total K,available K,pH and ＆lt;2μm clay content tend to be lower and bulk density tends to be higher in the village buffer zones than those out in Datian,Chenguang and Youfang respectively.iii） The population density,economic development and terrain might be the key driving forces contributing to the relationship between gathering firewood and forestland soil fertility.Higher population density leads to more massive firewood collection and imposes more pressure on forestland soil fertility.Decreasing the use of firewood stove may reduce firewood consumption and thus release the pressure of gathering firewood on forestland soil fertility.Terrain affects the accessibility to gathering firewood thus affects forestland soil fertility.Other driving forces influencing the relationship between gathering firewood and forestland soil fertility should also be taken into account in the further study.

Ecological Landscape Planning and Design of Zhuxi River in Chongqing

Based on the theories and methods of ecology,landscape architecture and water conservancy,combined with the current status of the ecological environment of Zhuxi River in Chongqing,ecological environment protection,landscape space shaping and river culture creation are determined as the core of the design.Based on the design concept of ecological landscape restoration,river ecological protection,waterfront landscape layout,cultural shaping,wetland construction,sponge city construction,etc.are proposed.The design and construction of the Zhuxi River ecological landscape will effectively improve its ecological environment and help to shape a good social and economic environment.This is a useful exploration in the practical application of domestic river ecological landscape design research.

基于照明分析和偏移成像实验的主动震源探测系统设计——以朱溪矿区为例

为了探讨利用绿色环保的非炸药主动震源技术勘查我国西部、南部复杂山地深部矿产资源的可行性,并提出可行的探测方案,以景德镇朱溪矿区为例开展了基于照明分析和叠前深度域偏移成像实验的主动源地震探测系统设计研究。在现场踏勘和充分收集地质、钻探成果的基础上,根据矿区42号线钻孔联合剖面和相应的岩石物性测量成果建立了地球物理模型。由于后续地震数据采集工作主要利用单分量纵波检波器开展,在地震波的数值模拟方面选用了粘声波方程;工区崎岖地表所带来的不规则自由表面问题则通过Acoustic-Elastic boundary Approach(AEA)方案解决。进行了震源-检波器组双向照明分析,以及高信噪比(20db)和低信噪比(6db)两种情况下的地震波叠前深度域逆时偏移成像实验。研究结果表明,通过合理布设较为密集的主动震源激发-接收系统,采用环境友好的非炸药主动震源技术可以查明目标区地下主要地层,和断层、逆掩推覆体等主要控矿构造的空间展布。后续实际的地震数据采集工作在本次研究的基础上开展,取得的朱溪矿区第一手非炸药震源绿色勘查成像剖面证明了本次研究所提出的探测方案是可行的和有效的。通过不断完善技术体系,非炸药主动震源技术有望为我国深部矿产资源勘探、隐伏断裂勘查、城市地下空间探测等研究领域提供一种环保、高效的技术手段。本次研究所采用的基于照明分析和偏移成像实验的复杂山地主动震源探测系统设计、论证方法值得进一步研究和推广。

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".

考亭先生朱熹与闽北医籍

朱熹作为理学集大成者和体系的建立者,对后世医家影响甚大。其长期生活在闽北,对闽北医家的影响更是如此。朱子理学内涵和朱熹个人理念推动了闽北医家著书立说,具体表现为寻理洞原影响闽北医籍注重医理讨论,心性理欲论和孝仁观影响了闽北医家的节欲养生思想与著书原因。朱子格物致知的具体内容以及其原创的纲目体编写方法也塑造着闽北医家编撰医书的方式。理学体系的建立促进了五运六气学说在中医学界的再次流行,朱熹关于普及教育的理念也深刻地影响着闽北医家的创作。

朱熹诗教与礼乐关系疏考

先秦以六经为教,《诗经》居首。朱熹既是儒家诗教传统的传承者也是诗教理论的创新者。朱熹以“性体情用”的哲学思想,重新解读和确认了儒家诗教的意义。这种理学式的思路也成为朱熹阐释礼乐关系的逻辑基础。他明确提出“诗本乐末”“礼乐同体”,从形而上的层面解决了诗教思想中的礼乐关系问题。他从礼乐的价值指向出发,明确了“敬”先“和”后的次第,使“礼”“乐”作为诗教的重要组成部分在具体实践中有了主从先后的分别,并进一步以“敬体和用”的理论讨论儒家诗教核心价值观“仁”的实现路径。立足朱熹诗教思想,深入考释其对礼乐关系的解读,有助于进一步理解朱熹诗教思想。

竹溪生漆产业助力县域经济发展路径研究

在中国经济高速发展背景下,县域经济发展备受关注。本文以助力县域经济发展为背景,以促进生漆产业振兴为目标,通过调研,分别从竹溪生漆产业概况、存在的问题、发展路径等方面进行分析与研究,有针对性的提出竹溪生漆产业的振兴路径,助力生漆产业转型升级,促进竹溪经济快速发展。

赣东北朱溪矿床云英脉型钨矿体及矽卡岩型钨铜矿体成因关系——来自石榴子石、白钨矿原位U-Pb年代学及微量元素特征的证据

朱溪矿床是江南钨矿带中产于燕山期中酸性侵入岩与晚古生代碳酸盐岩接触带附近以矽卡岩矿体为主的钨铜矿床,发育“上铜下钨”的空间分带。浅部发育矽卡岩型和脉型铜矿体,深部发育矽卡岩型钨铜矿体、云英细脉-网脉型钨矿体及蚀变花岗岩型钨矿体。浅部矽卡岩型铜矿体中石榴子石U-Pb年龄为152.6±2.6 Ma、深部云英脉型钨矿体中白钨矿U-Pb年龄为153.4±2.2 Ma、深部矽卡岩型钨铜矿体中白钨矿U-Pb年龄为153.9±2.7 Ma,三者时代在误差范围内一致,表明钨、铜矿化均形成于同一热液体系,结合云英脉型钨矿体和矽卡岩型钨铜矿体中两类白钨矿的微量元素特征分析,流体起源于富WO_(4)^(2-)、低Sr的高分异岩浆热液,白钨矿是以Ca^(2+)空位的方式置换REE^(3+),稀土元素的分配行为记录了不同类型矿化流体性质。云英脉型钨矿化形成于还原环境,且氧逸度的显著降低以及围岩提供大量Ca^(2+)促进了白钨矿的沉淀,而矽卡岩型钨铜矿化为相对开放的热液体系,后期经历了氧逸度升高,增强了流体富集金属Cu的能力,从而萃取活化围岩中的铜元素进入到流体中,随之温度降低使碳酸盐矿物和无水矽卡岩矿物发生交代,导致铜的沉淀。

江西朱溪钨矿床矽卡岩矿物热红外光谱学特征研究

朱溪钨矿床白钨矿化与矽卡岩化密切相关,白钨矿多与石榴子石、透辉石等矽卡岩矿物一起产出。该研究对朱溪典型矽卡岩矿物如石榴子石、透辉石、符山石、硅灰石、阳起石等进行显微红外光谱测量和电子探针分析,探究朱溪矽卡岩矿物的热红外光谱特征及其对成矿的指示意义,并建立朱溪地区的矽卡岩矿物热红外光谱库。结果表明,朱溪钨矿床石榴子石主要为钙铝—钙铁榴石系列,在800和920 cm^(-1)附近存在一大一小两个吸收峰,在880 cm^(-1)附近存在特征吸收谷;当石榴子石成分中钙铝榴石含量大于50%时,石榴子石特征吸收谷位于880~900 cm^(-1),当钙铝榴石含量小于50%时,石榴子石吸收谷位于865~875 cm^(-1)。随着Al 2O 3含量增加,其特征吸收谷向高波数方向移动,钙铝榴石偏向高波数,钙铁榴石偏向低波数;辉石主要为透辉石—钙铁辉石系列,在850~950 cm^(-1)波数范围内存在诊断式、呈阶梯状降低的吸收峰,且在1050 cm^(-1)处存在吸收峰,在1000 cm^(-1)存在微弱的双谷式吸收特征;随着透辉石含量的减少,MgO含量减少,透辉石吸收峰向低波数方向移动,钙铁辉石的吸收峰相对于透辉石集中在低波数范围内,与石榴子石的变化规律一致,推测与Al、Mg化学性质比Fe活泼有关。符山石拥有850~950 cm^(-1)范围内与透辉石类似形态的吸收峰,区别在于符山石在800 cm^(-1)左右还存在一吸收峰。硅灰石在875,1000和1060 cm^(-1)附近存在一大两小三个吸收峰,在980和1040 cm^(-1)附近存在两个特征吸收谷。阳起石在750和900 cm^(-1)附近存在一小一大两个吸收峰,在770,930和1020 cm^(-1)附近存在三个特征吸收谷。朱溪矿床白钨矿与石榴子石、透辉石关系最为密切,主要沿石榴子石和透辉石边界呈脉状生长,其热红外光谱可以作为寻找白钨矿的指示标志。上述研究成果,对深入分析和研究江西朱溪钨矿床的矿物学特征及成因环境,以及探索利用热红外技术指导矽卡岩矿物分带与找矿勘查的可能性等具有理论和实际意义。

朱溪钨铜矿床深部石英脉型黑钨矿成因及其地质意义

近年来赣东北地区发现的朱溪大型钨(铜)矿床,以发育矽卡岩型、蚀变花岗岩型、云英岩(石英)脉型和似层状白钨矿体为主,最近在ZK4213钻孔深部花岗岩体中首次发现石英脉型黑钨矿体。在野外编录和岩矿鉴定基础上,对该石英脉型黑钨矿进行了电子探针分析,其中WO_(3)含量为74.3%~76.7%(平均75.7%),MnO为12.8%~13.8%(平均13.2%),FeO为10.3%~11.6%(平均11.1%),FeO/MnO值为0.75~0.90(平均0.85),晶体化学式为(Fe_(0.43-0.49)Mn_(0.54-0.59))_(1.01-1.05)W_(0.98-0.99)O_(4),属于铁钨锰矿系列。黑钨矿相对富锰的特征指示其可能形成于相对高温、偏还原的弱酸性环境。结合矿区成岩成矿作用研究,初步认为朱溪地区可能经历了多期成岩成矿作用,即在晚侏罗世主成岩成矿期之后,可能又经历过新的成岩成矿事件。朱溪矿区深部新发现的石英脉型黑钨矿体也极有可能为该新一期成矿事件的产物。

赣东北朱溪钨铜矿床辉石矿物光谱-地球化学特征

为厘定江西朱溪钨铜矿矿床辉石矿物类型、矿物组合等矿物学特征,深入研究辉石矿物光谱-地球化学特征间的关系,对矿区ZK4208、ZK4210、ZK4211三个钻孔进行热红外光谱、显微镜下鉴定及电子探针综合分析,对矿物中Mg、Fe等主量元素含量进行定量测定,确定研究区辉石矿物以透辉石-钙铁辉石端元为主,并对辉石矿物波长特征与距热源中心距离、矿物主量元素含量间的相关性进行分析。结果表明,钻孔ZK4211中辉石矿物Fe、Mn替代Mg离子的过程可能会导致辉石波长向短波方向移动;样品点至热源中心的距离与辉石矿物的光谱特征呈线性相关关系;自岩体向外围,辉石分布及光谱特征具有分带性。

江门市珠西枢纽新城地质灾害危险性评估及防治措施

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《光谱学与光谱分析》2023年征订启事

国内邮发代码:82-68国外发行代码:M905《光谱学与光谱分析》1981年创刊,国内统一刊号:CN 11-2200/O4,国际标准刊号:ISSN 1000-0593,CODEN码:GYGFED,国内外公开发行,大16开本,332页,月刊;是中国科协主管,中国光学学会主办,钢铁研究总院、中国科学院物理研究所、北京大学、清华大学共同承办的学术性刊物。北京大学出版社出版,每期售价115元,全年1380元。刊登主要内容:激光光谱测量、红外、拉曼、紫外、可见光谱、发射光谱、吸收光谱、X射线荧光光谱、激光显微光谱、光谱化学分析、国内外光谱化学分析领域内的最新研究成果、开创性研究论文、学科发展前沿和最新进展、综合评述、研究简报、问题讨论、书刊评述。

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赣东北朱溪超大型钨矿床中白钨矿的稀土、微量元素地球化学特征及其Sm-Nd定年

赣东北朱溪超大型钨矿床是目前世界上最大的夕卡岩型钨矿床,为确定其成矿物质来源及成矿时代,在详细钻孔岩心编录基础上,本文对白钨矿运用LA-ICP-MS法分析了其单矿物的微量元素、稀土元素,并进行Sm-Nd同位素定年研究。结果显示:白钨矿微量元素中Mo、Nb、Ta富集,而Rb/Sr<0.04,Nb/Ta=1.69~8.46、Zr/Hf=3.06~6.75,显示成矿物质的壳源特征。白钨矿的∑REE变化大(∑REE=3.25×10^(-6)~229.95×10^(-6)),LREE与HREE之间分馏明显((La/Yb)N=36~19 984),属于轻稀土富集型。依据δEu值的特征,将白钨矿分为δEu正异常(δEu=1.44~9.06)的轻稀土富集型和δEu负异常(δEu=-0.25^-0.82)的轻稀土富集型;在空间上,由远到近接近花岗岩,白钨矿的∑REE逐渐升高,δEu由正异常逐渐转变为负异常,有与花岗岩稀土配分曲线趋于一致的趋势。白钨矿Sm-Nd等时线年龄为(144±5)Ma,143 Nd/144 Nd初始比值为0.512 020,其εNd(t)为-9.753,二阶段模式年龄为1 745 Ma,其年龄与物质来源与朱溪花岗岩的一致,表明朱溪钨矿床是朱溪矿区隐伏花岗岩进一步演化的产物。

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朱溪铜钨多金属矿床位于赣东北深大断裂北西侧。矿体主要产于燕山期侵入岩与碳酸盐岩接触带的矽卡岩或矽卡岩化大理岩中,代表性矽卡岩矿物有石榴子石、透辉石、透闪石、硅灰石、蛇纹石、金云母、符山石、绿泥石等。根据矿物共生组合及交代关系推断流体经历了5个阶段,分别为矽卡岩阶段、退化蚀变阶段、石英硫化物阶段、石英碳酸盐阶段和表生氧化阶段。特征矿物的电子探针分析结果表明,石榴子石主要为钙铝榴石—钙铁榴石;辉石以透辉石—钙铁辉石系列为主;角闪石属钙角闪石系列;绿泥石主要是密绿泥石和斜绿泥石。推测岩浆侵入后,在矽卡岩阶段为中酸性弱氧化条件,在退化蚀变阶段氧逸度和p H值升高,氧化物析出,随着氧逸度的又一次降低,金属硫化物沉淀。最后,通过其矿物成分特征推测该矿床金属矿化的种类。