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1.
西准包古图呼的合铜矿地质特征、成因及成矿规律研究   总被引:1,自引:0,他引:1  
新疆西准包古图矿区呼的合铜矿位于巴尔喀什华力西期斑岩成矿带.大地构造位置属哈萨克斯坦-准噶尔板块,唐巴勒-卡拉麦里古生代复合沟孤带,包古图岛弧区.矿床处于达尔布特和克乌深大断裂间,次级NS向与NE向断裂交汇处.Ⅴ号岩体属深源、浅成中酸性复合相岩体.含矿岩石以中粗粒、斑状、似斑状结构的石英闪长岩、花岗闪长斑岩为主,次有花岗闪长岩、花岗斑岩、黑云母花岗闪长岩等,形成时间为320~300 Ma,岩石蚀变强烈,蚀变分带自岩体中心向外构成钾长石和粒状石英核-钾化带-绢英化带-青盤岩化带.金属矿物组合自岩体中心向外变化规律为:(黄铁矿-辉钼矿-黄铜矿)→(黄铁矿-黄铜矿-闪锌矿-辉钼矿)→(黄铁矿-黄铜矿-毒砂-Te-Bi-Ag-Au的矿物).有益元素主要为铜、钼、金、银等元素,矿石类型自岩体中心向外的变化规律为:Mo(Cu)→Cu(Mo)→Cu(Au)→Au.矿石构造为细粒浸染状和细脉浸染状.矿石品位低、矿化均匀,成矿物质主要来自与其共生的岩浆岩,属典型斑岩型铜矿.构造、岩石、蚀变、矿物、及成矿元素在空间、时间上变化规律较强,与矿化富集有密切联系.  相似文献   

2.
颜代蓉  邓晓东  胡浩  李建威 《岩石学报》2012,28(10):3373-3388
阮家湾花岗闪长岩和犀牛山花岗闪长斑岩位于鄂东南矿集区东南缘,前者产有鄂东南地区最大的矽卡岩型钨-铜-钼矿床,而后者迄今仅发现有斑岩型铜矿化点.本文对阮家湾花岗闪长岩和犀牛山花岗闪长斑岩开展了系统的锆石U-Pb年代学、元素地球化学和Sr-Nd-Hf同位素组成的研究,以深入讨论这些岩体的岩石成因及其成矿和找矿意义.锆石U-Pb定年结果表明,阮家湾花岗闪长岩和犀牛山花岗闪长斑岩的侵位年龄分别为143±1Ma和147±1Ma( 1σ),是鄂东南地区最老的含钨-铜-钼矿化侵入岩.阮家湾花岗闪长岩和犀牛山花岗闪长斑岩均为高钾钙碱性岩体,富集Rb、Ba、Th和La等大离子亲石元素,亏损Nb、Ta和Zr等高场强元素.岩石具有Sr含量高(分别为681 × 10-6 ~874×10-6和575×10-6 ~687×10-6)、Y含量低(分别为12.0×10-6 ~ 17.4×10-6和9.7×10-6~14.0×10-6)、Sr/Y比值大(分别为39 ~ 61和47 ~ 62)、轻重稀土分馏强烈(Yb含量分别为0.90×10-6~1.49×10-6和0.62 × 10-6 ~1.01×10-6;La/Yb比值分别为42 ~ 54和48 ~ 60)等特点.全岩Sr-Nd同位素分析和锆石Hf同位素分析结果表明,阮家湾花岗闪长岩的(87Sr/86Sr)i为0.7062 ~0.7063,εNd(t)为-5.8 ~-6.2,εHf(t)为-12.0~ -6.8;犀牛山花岗闪长斑岩的(87Sr/86 Sr)i为~0.7065,εNd(t)为-5.6~ -6.5.元素和同位素地球化学特征表明,阮家湾花岗闪长岩和犀牛山花岗闪长斑岩是由富集地幔部分熔融形成的岩浆同化混染下地壳物质并发生分离结晶作用的产物.矿物组合及矿物化学组成表明,阮家湾钨铜钼矿床的含矿岩体具有更低的氧逸度和更多的地壳物质混染,而犀牛山花岗闪长斑岩则具有较高的氧逸度(以出现岩浆硬石膏为标志).另外,犀牛山岩体中挥发份的含量与鄂东南地区最大的斑岩-矽卡岩型铜矿——铜山口矿床的含矿岩体类似,表明有利于斑岩型铜矿床的形成.犀牛山岩体内部斑岩型铜矿点和铁帽发育,进一步说明犀牛山岩体具有较大的斑岩型铜矿床找矿潜力,在今后的找矿工作中应给予关注.  相似文献   

3.
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。  相似文献   

4.
小赛什腾铜矿赋存于华里西期闪长岩、闪长斑岩中,全岩矿化,岩体普遍含铜,岩体中w(Cu)平均值>500×10-6;铜矿体主要由含铜闪长斑岩、闪长岩等组成,矿石呈中细粒状、斑状结构,细脉浸染状、块状构造;矿体、矿化体与围岩逐渐过渡,界线不清,整个岩体中普遍可见弱孔雀石化.化探异常在平面上由岩体中心到围岩存在明显的元素分带现象,即,W,Mo,(Bi)→Cu,Au→As,(Hg),表现出与典型斑岩型铜矿相似的地球化学特征.岩体蚀变有硅化、碳酸盐化、绿帘石化、绿泥石化、绢云母化、黄铁矿化,少量钾化,在与大理岩的接触带附近发育夕卡岩化.  相似文献   

5.
三岔口铜矿床位于新疆东天山大南湖岛弧带的东北缘。目前对于三岔口铜矿床的成因类型及成矿年代还存在争议。三岔口铜矿床中赋矿岩体为闪长岩-花岗闪长岩,发育黑云母化、硅化、绢英岩化、青磐岩化等。测得三岔口铜矿床辉钼矿Re-Os年龄为416Ma±6.4 Ma,含矿闪长岩中锆石LA-ICP-MS U-Pb年龄为425 Ma±3.9 Ma,反映该矿床形成于中志留世。矿区内闪长岩-花岗闪长岩w(Na_2O+K_2O)为3.88%~4.68%,A/NCK值均大于1,为铝饱和岩石。岩体贫钾(w(K_2O)0.47%~1.18%)富钠(w(Na_2O)_2.83%~4.23%),w(TiO_2)偏低(0.41%~0.46%),多属于低钾拉斑系列。岩体富集w(Ba)(260×10~(-6)~4 810×10~(-6)),w(Sr)(644×10~(-6)~797×10~(-6))等大离子亲石元素,亏损w(Nb)(2.1×10~(-6)~2.6×10~(-6)),w(Ta)(0.1×10~(-6)),w(Zr)(11.2×10~(-6)~13.1×10~(-6))等高场强元素,具岛弧岩浆岩的特征。岩体富Na贫K,K_2O/Na_2O0.42,且具有高w(Al_2O_3)(≥16.65%),w(SiO_2)(≥61.3%),w(Sr)(≥644×10~(-6))以及较低的w(Y)(≤13.7×10~(-6))和w(Yb)(≤1.41×10~(-6)),具O型埃达克岩的特征,表明三岔口铜矿床形成于俯冲岛弧环境。结合研究区域内铜(钼)矿床的成矿时代及矿床类型,得出东天山地区有三期斑岩型矿床成矿作用:志留纪的三岔口、玉海斑岩型铜矿床,石炭纪的土屋-延东、延西等斑岩型铜矿床,以及三叠纪的东戈壁、白山斑岩型钼矿床。  相似文献   

6.
包古图斑岩铜矿位于新疆西准噶尔地区,是区内规模最大的斑岩型矿床,成矿作用与晚石炭世中酸性侵入体密切相关。Ⅲ-2岩体位于矿区南部,该岩体全岩矿化,但品位较低,是探讨成矿岩浆性质的理想对象。本文结合岩石学和角闪石、锆石等矿物成分分析,通过与典型斑岩铜矿进行对比,探讨了成矿岩浆的氧逸度。研究表明,包古图Ⅲ-2岩体以石英闪长(玢)岩和闪长岩为主,少量辉石闪长岩,主要由斜长石、角闪石、黑云母、石英和钾长石组成,含少量钛铁矿、榍石和磷灰石。石英闪长岩中早期结晶的自形角闪石属于钙质闪石,Mg~#较高(0.72~1.00),成分分析指示成矿岩浆的氧逸度为:△NNO+1.4~△NNO+2.6,位于斑岩铜矿含矿岩体的分布范围。从中分选出的锆石REE含量高(338×10~(-6)~959×10~(-6)),具有左倾型稀土配分模式,轻稀土亏损,重稀土富集,显示强烈Ce正异常和Eu负异常。Ce~(4+)/Ce~(3+)比值为29.55~89.50,Eu/Eu~*比值为0.32~0.47,分布于斑岩铜矿含矿岩体和未矿化岩体的叠加部位。研究结果显示,包古图斑岩铜矿Ⅲ-2岩体成矿岩浆氧逸度较高,有利于成矿元素的溶解和迁移,对斑岩铜矿的形成有促进作用。  相似文献   

7.
张雪旎  聂凤军  王佳新 《地质通报》2015,34(6):1203-1216
斯克瑞斯斑岩型铜矿位于希腊北部哈尔基迪基半岛,塞尔维亚马其顿成矿带。矿体赋存于侵入到韦尔蒂斯科斯组的古近纪—新近纪碱性岩体中,岩体的分布受深部断裂影响。截至2011年,斯克瑞斯矿床已开采5.2×108t铜,Cu平均品位为0.5%,Au平均品位为0.8×10-6,Pd平均品位为110×10-9,Pt平均品位为17×10-9。铜-金矿化呈脉状、网脉状及浸染状分布于岩体及围岩中。矿石矿物主要为黄铜矿、斑铜矿、黄铁矿等,与矿化有关的围岩蚀变主要有钾长石化、硅化、青磐岩化、绢云母化等。锆石U-Pb年龄、全岩Ar-Ar年龄和矿床地球化学特征均显示,岩浆侵位与成矿作用之间关系密切,其形成时代约为19Ma。该矿床以Pd-Pt含量较高为特征。对斯克瑞斯斑岩型富铂族元素斑岩铜矿特点及成矿规律的系统总结,可以为在中国境内寻找同类矿床提供参考。  相似文献   

8.
铁列库坦斑岩铜矿位于南天山主脊深断裂南侧,处在晚加里东优地槽褶皱带与华力西弧后盆地褶皱带的交替部位。成矿岩体为英闪岩-黑云母花岗闪长岩,分布于同时代超基性岩带外侧的晚古生代中—酸性岩浆岩杂岩带中,与深断裂有关,相当于M(地幔)型中的地壳—地幔混合成因花岗岩类岩石。斑岩型蚀变具明显的垂直分带,由地表向下依次为青盘岩化带、泥岩化带、似千枚岩化带。铜矿化主要产于蚀变岩体边缘相第Ⅲ带中,呈星散状和细脉浸染状,与黄铁矿紧密伴生,多为低品位矿石;围岩中的铜矿化赋存于石英脉中,品位较富。矿床类型属于花岗闪长岩亚型。矿质来自岩体结晶过程中形成的残余热液。  相似文献   

9.
新疆西准噶尔包古图地区斑岩型铜矿化发育,蚀变矿化特征随岩体不同存在显著差异。文章通过岩石学、矿相学和微量元素地球化学的方法,重点研究了Ⅲ号和Ⅴ号岩体的矿化特征和成矿元素迁移规律。结果表明:Ⅲ号岩体矿化中等,以黄铁矿、磁黄铁矿和黄铜矿为主,呈浸染状,硫化物脉少见;Ⅴ号岩体内部及其与围岩接触带产出大型铜矿床,金属矿物主要有黄铁矿、黄铜矿和辉钼矿,呈浸染状和细脉-网脉状分布。Ⅲ号岩体角闪石英闪长岩形成于岩浆-热液过渡阶段,与石英(花岗)闪长岩对比显示,挥发分出溶过程中,Cs、Rb、Ba、Th、U迁移进入挥发相,稀土元素稳定未迁移,Cu、Bi显著富集,Mo和Sb被流体迁移带走,形成热液矿化。Ⅴ号岩体钾化和硅化样品代表了不同的流体作用阶段,与未蚀变样品对比显示,在钾化阶段Nb、Ta、Zr、Hf性质稳定,轻稀土元素发生显著迁移,在硅化阶段轻稀土元素富集;重稀土元素在岩浆-热液演化过程保持稳定。Cu、Mo和Bi在钾化作用阶段富集成矿,Zn和Sb则主要在晚期石英脉中富集。  相似文献   

10.
龙门钼矿床是太行山北段成矿带内近些年探明的一个大型钼矿床,钼矿体主要产于花岗斑岩、闪长岩和新太古代片麻岩中,以角砾岩型矿石为主.矿区内辉钼矿化主要类型为浸染状、薄膜状、细脉状,发育钾长石化、硅化、绢云母化、黄铁矿化蚀变,类似典型的斑岩型矿床的矿化和蚀变特征.文章对龙门钼矿床的闪长岩和花岗斑岩进行了LA-ICP-MS锆石U-Pb同位素测年,获得闪长岩的锆石谐和年龄为(138.1±0.6)Ma(MSWD=0.6,n=21),花岗斑岩的锆石谐和年龄为(137.0±0.7)Ma(MSWD=1.03,n=17),结合地质特征,显示花岗斑岩晚于闪长岩形成.对主要矿石类型中的辉钼矿进行了Re-Os同位素测年,获得辉钼矿的Re-Os等时线年龄为(136.5±1.5)Ma,与赋矿的花岗斑岩的侵位年龄相一致,二者应为同一岩浆-流体活动的产物.龙门钼矿床辉钼矿样品的w(Re)为13.1×10-6~59.3×10-6,表明其成矿物质来源于壳幔混源.龙门矿区及太行山北段成矿带内的隐爆角砾岩体是下一步找矿勘查的方向.  相似文献   

11.
Komatiites are mantle-derived ultramafic volcanic rocks. Komatiites have been discovered in several States of India, notably in Karnataka. Studies on the distribution of trace-elements in the komatiites of India are very few. This paper proposes a simple, accurate, precise, rapid, and non-destructive wavelength-dispersive x-ray fluorescence (WDXRF) spectrometric technique for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in komatiites, and discusses the accuracy, precision, limits of detection, x-ray spectral-line interferences, inter-element effects, speed, advantages, and limitations of the technique. The accuracy of the technique is excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Zr, Nb, Ba, Pb, and Th and very good (within 4%) for Y. The precision is also excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th. The limits of detection are: 1 ppm for Sc and V; 2 ppm for Cr, Co, and Ni; 3 ppm for Cu, Zn, Rb, and Sr; 4 ppm for Y and Zr; 6 ppm for Nb; 10 ppm for Ba; 13 ppm for Pb; and 14 ppm for Th. The time taken for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in a batch of 24 samples of komatiites, for a replication of four analyses per sample, by one operator, using a manual WDXRF spectrometer, is only 60 hours.  相似文献   

12.
最新的流行病学研究表明,空气中较高浓度的悬浮细颗粒可能对人类的健康有不利的影响。根据该项研究显示,由于心脏病、慢性呼吸问题和肺功能指标恶化而导致死亡率的升高与细尘粒子有关。这些研究结果已经促使欧盟于1999年4月出台了限制空气中二氧化硫、二氧化氮、氧化氮、铅和颗粒物含量的法案(1999/30/EC),对各项指标包括对可吸入PM10颗粒的浓度提出了新的限制性指标。PM10颗粒是指可以通过预分级器分离采集的气体动力学直径小于10μm的细颗粒。目前研究的兴趣重点逐步偏向PM2.5这些更细微颗粒物,PM2.5这种颗粒物对健康有明显的不利影响。在欧盟指令2008/50/EC中,对PM10和PM2.5都提  相似文献   

13.
This paper reports the first results of a study of 11 isotope systems (3He/4He, 40Ar/36Ar, 34S/32S, 65Cu/63Cu, 62Ni/60Ni, 87Sr/86Sr, 143Nd/144Nd, 206–208Pb/204Pb, Hf–Nd, U–Pb, and Re–Os) in the rocks and ores of the Cu–Ni–PGE deposits of the Norilsk ore district. Almost all the results were obtained at the Center of Isotopic Research of the Karpinskii All-Russia Research Institute of Geology. The use of a number of independent genetic isotopic signatures and comprehensive isotopic knowledge provided a methodic basis for the interpretation of approximately 5000 isotopic analyses of various elements. The presence of materials from two sources, crust and mantle, was detected in the composition of the rocks and ores. The contribution of the crustal source is especially significant in the paleofluids (gas–liquid microinclusions) of the ore-forming medium. Crustal solutions were probably a transport medium during ore formation. Air argon is dominant in the ores, which indicates a connection between the paleofluids and the atmosphere. This suggests intense groundwater circulation during the crystallization of ore minerals. The age of the rocks and ores of the Norilsk deposits was determined. The stage of orebody formation is restricted to a narrow age interval of 250 ± 10 Ma. An isotopic criterion was proposed for the ore-bearing potential of mafic intrusions in the Norilsk–Taimyr region. It includes several interrelated isotopic ratios of various elements: He, Ar, S, and others.  相似文献   

14.
本文介绍样品经四硼酸锂熔融制成玻璃小饼。采用Lachance模式和理论a系数来校正元素间的效应,由3080E型X-射线荧光谱仪和DF-350B数据处理系统完成硅酸盐中十三个项目的测定。  相似文献   

15.
本文拟定了一种以熔融法制备样片,用X射线荧光光谱测定硅酸盐类样品中Si、Fe、Al、Tj、Mn、Ca、Mg、K、Na、P等元素的分析方法。在对不同靶材X光管和分光晶体实验对比的基础上,选择了最佳的测量条件。该法具有快速、准确,测量范围广,检测限低,价格便宜等优点。经过近百个各种类型标样或管理样品的分析对比表明,本法不仅适用于硅酸盐类岩石样品的分析,还适用于铁矿、铝土矿、碳酸盐类岩矿样品以及水泥、耐火材料等样品的分析。  相似文献   

16.
Mining induced subsidence can significantly affect mining costs where major surface facilities and natural environment need to be protected. Overburden grout injection is a technology used to control coal mine subsidence by injecting the mine waste material extracted from the coal back into the inter-burden rock during longwall mining. The flowing slurry is here categorised as a nonlinear viscous cohesive (Bingham plastic) fluid. During longwall mining the grout slurry is pumped into the separated beds of the rock mass through a central vertical borehole, which is drilled deep into the inter-burden rock strata above the coal seam. However, a blockage can occur in the injection system when the slurry velocity falls below a certain critical threshold velocity, indicating a material phase change from cohesive-viscous to cohesive-frictional. In situ field injection tests through boreholes have been simulated at a smaller scale at the CSIRO laboratory in Brisbane by pumping the slurry through a radial disk (gap = 4 mm) from its centre. Laboratory experiments indicate a general, nonlinear, cohesive, viscous, frictional model for shear behaviour of the slurry, in which the material shear parameters are functions of the disk radial distance. Complete dimensional and dimensionless analytical solutions have been developed based on an approach related to Bingham–Herschel–Bulkley fluid mechanics. The derived formulae include relations for minimum pump pressure, local pressure and pressure gradient, wall shear stress, volume rate, velocity and velocity gradient. The theoretical results match the experimental measurements. The experiments covered slurries with maximum particle sizes of 0.5 to 2 mm with about 50% being larger than 100 µm. The viscosities at the various solids concentrations were measured with a standard torsion viscometer. This study differs from the previous research in several distinct aspects, namely, consideration of the variable shear parameters rather than fixed values, inclusion of total nonlinear behaviour, and implementation of a friction function to mimic behaviour of the deposited and consolidating stiff slurry, which can cause a significant pressure rise as a result of the increased shear resistance.  相似文献   

17.
18.
Between 1985 and 1991, two new mountain protected areas (MTNPA) covering more than 35,000 km2 and based on participatory management models — the Makalu-Barun National Park and Conservation Area, Nepal, and Qomolangma Nature Preserve, Tibet Autonomous Region — were successfully established through the collaborative efforts of Woodlands Mountain Institute and conservationists in China and Nepal. Characteristics common to both projects include the importance of establishing (1) effective rationales, (2) local support constituencies, (3) a senior advisory group, (4) a task force, (5) linkages between conservation and development, and (6) fund raising mechanisms. The lessons derived from the experiences of Woodlands Mountain Institute are of significant value to others in preserving MTNPA. Increased collaboration and communication between all interested in conservation, however, will remain a critical component for expanding mountain protected area coverage to throughout the world.  相似文献   

19.
岩石密度和超高压岩石折返速率   总被引:1,自引:3,他引:1  
在常温常压条件下对中国大陆科学钻CCSD主孔100-3000米岩心样品进行了密度测量,建立了密度连续剖面,并界定了不同超高压岩石的密度值。通过对比高温高压物性实验资料,岩石密度随着退变程度增强而降低,榴辉岩密度变化序列为3.52g/cm3→3.49g/cm3→3.07g/cm3→2.93g/cm3。超高压长英质岩石密度变化序列为3.00g/cm→2.80g/cm3→2.65g/cm3。上述实验资料是讨论不同折返阶段岩石所受浮力的基础,为研究折返速率大小提供了基本参数。本文通过折返板块运动平衡时,上浮力与粘滞力平衡这一关系式,定量研究了大陆俯冲板块的折返速率,认为密度差产生上浮力从而引起折返,温度对板块折返速率的影响最为显著;密度差大小、折返角度、折返板块大小对折返速率也有直接的影响。定量模拟分析表明,在温度高于850℃时,板块的折返速率可以超过100mm/a;当温度降至700℃时,折返速率则低于1.5mm/a。作者认为在折返早期,温度较高,板块快速折返至60-70km榴辉岩相深度;随着传导散热,温度降低,板块以较慢的速率折返至中下地壳。折返速率的估算表明,浮力是板块折返第一阶段(从>100km深部折返至<40km的中下地壳)的主要驱动力。  相似文献   

20.
《Applied Geochemistry》2001,16(2):137-159
Five hundred and ninety-eight samples of terrestrial moss (Hylocomium splendens and Pleurozium schreberi) collected from a 188,000 km2 area of the central Barents region (NE Norway, N Finland, NW Russia) were analysed by ICP-AES and ICP-MS. Analytical results for Al, B, Ba, Ca, K, La, Mg, Mn, Na, P, Rb, Si, Sr, Th, U and Y concentrations are reported here. Graphical methods of data analysis, such as geochemical maps, cumulative frequency diagrams, boxplots and scatterplots, are used to interpret the origin of the patterns for these elements. None of the elements reported here are emitted in significant amounts from the smelting industry on the Kola Peninsula. Despite the conventional view that moss chemistry reflects atmospheric element input, the nature of the underlying mineral substrate (regolith or bedrock) is found to have a considerable influence on moss composition for several elements. This influence of the chemistry of the mineral substrate can take place in a variety of ways. (1) It can be completely natural, reflecting the ability of higher plants to take up elements from deep soil horizons and shed them with litterfall onto the surface. (2) It can result from naturally increased soil dust input where vegetation is scarce due to harsh climatic conditions for instance. Alternatively, substrate influence can be enhanced by human activity, such as open-cast mining, creation of ‘technogenic deserts’, or handling, transport and storage of ore and ore products, all of which magnify the natural elemental flux from bedrock to ground vegetation. Seaspray is another natural process affecting moss composition in the area (Mg, Na), and this is most visible in the Norwegian part of the study area. Presence or absence of some plant species, e.g., lichens, seems to influence moss chemistry. This is shown by the low concentrations of B or K in moss on the Finnish and Norwegian side of the (fenced) border with Russia, contrasting with high concentrations on the other side (intensive reindeer husbandry west of the border has selectively depleted the lichen population).  相似文献   

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