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兰坪盆地东缘SEDEX型铅锌矿床地质特征及成矿预测
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摘要
兰坪盆地是我国三江成矿区中重要的多金属成矿带之一,有着巨大的找矿前景。在盆地北部东缘维西-乔后断裂带附近的三合洞组灰岩中,产出了一系列中型铅锌矿,并具有很大的成矿远景。该区铅锌矿矿床成因类型还不确定,对其开展矿床成因的研究工作,可以为铅锌矿区域成矿规律和找矿预测提供理论依据,意义重大。本文通过对盆地东缘青甸湾-菜子地铅锌矿床的资料收集整理、野外实地考察、光薄片显微镜鉴定、电子探针分析、稳定同位素分析、矿石及矿物的微量稀土元素分析,取得了如下重要认识:
     1.青甸湾-菜子地铅锌矿主矿体呈层状,似层状或透镜状赋存于上三叠统三合洞组灰岩中,严格受到地层的控制。样品中发现了大量的反映同生沉积的标志如:纹层构造、条纹条带构造、黄铁矿条带软沉积构造、黄铁矿草莓状结构、黄铁矿胶状构造、闪锌矿同心环状构造等。
     2.青甸湾矿床手标本和光薄片镜下观察发现硫化物均为细粒产出,反映了快速沉积的特点。矿物组合简单,具体为闪锌矿+方铅矿+黄铁矿+毒砂+白云石+方解石+重晶石+石英。对硫化物电子探针成分分析发现,闪锌矿、黄铁矿、方铅矿成分标型都反映热水了沉积成因的特征。
     3.青甸湾矿床S同位素组成,δ34S‰值的变化范围为3.7-10‰,极差仅为6.3‰,平均值为6.55‰(N=14),反映硫来自于海水硫酸盐的无机还原。矿石和矿物稀土元素组成:稀土总量低,LREE富集并有明显的Eu正异常,反映了喷流沉积的特征。
     4.综合对比了青甸湾-菜子地矿床与MVT和SEDEX矿床的特征,初步认为青甸湾-菜子地矿床为喷流沉积型(SEDEX)矿床。
     5.根据SEDEX矿床产出特征,提取出盆地三合洞组分布情况,结合盆地内地球化学异常,划分出具有Pb-Zn异常组合的三合洞组分布区,作为找矿远景区。
Lanping Basin is one of the most important polymetallic Deposit zones in "Sanjiang" metallog enic belt,China. there is great potential for exploration. Sanhedong Group limestone which is near the Weixi-Qiaohou fault at the north eastern margin of the Lanping basin, output of a series of medium-sized Pb-Zn deposits, and mineralization has great vision. Genesis type of the lead-zin c deposits in the area is uncertain, Research work for the genesis of these Pb-Zn deposit is very i mportant,which can provide a theoretical basis for regional metallogenic regularity and exploratory forecast. Based on the field investigation of Qingdianwan-Caizidi Pb-Zn deposits, and the data coll ection and analyzed indoor, microscope identification of slices, electron microprobe analysis, stable isotope analysis and trace rare earth elements in ore and mineral analysis,The writer obtain the foll owing conclusions:
     1. The main ore bodies of Qingdianwan-Caizid Pb-Zn deposits are layered, stratiform or lentic ular in the Upper Sanhedong Group limestone, strictly contr-olled by the formation. A large numbe r of typical signs of the synsedimentary deposit are founded such as:laminated structure,striped b and structure, the soft sedimentary pyrite band structure, strawberry-like structure,colloidal structure of pyrite, sphalerite concentric structure et al.
     2. Sulfide in the hand specimen and slices are fine-grained reflecting the characteristics of ra pid deposition. Mineral composition is simple.There are sphalerite +galena+pyrite+arsenopyrite+dolo mite+calcite+barite+quartz. Components of the electron microprobe analysis of sulfide, sphalerite, p yrite, galena compositional types reflect the characteristics of sedimentary origin.
     3. S isotopic compositions of Qingdianwan depositsδ34S‰values range from 3.7~10‰, range of only 6.3‰, an average of 6.55‰(N= 14), and sulfur mainly from the inorganic redu ction of seawater sulfate. REE composition of ores and minerals:low total REE, LREE enrichment and positive Eu anomalies,reflecting the characteristics of Sedimentary Exhalative Deposit.
     4. comprehensive comparison of the Qingdianwan-Caizidi deposits to MVT and SEDEX deposi-ts educe that Qingdianwan-Caizidi Pb-Zndeposit is Sedimentary Exhalative Deposit.
     5. According to SEDEX mineralization characteristics, extracted Sanhedong group from the dis tribution of basin, combine to geochemical anomalies within the basin, carved out of a combinatio n of Pb-Zn anomalies Sanhedong groups are distributed, as prospecting areas.
引文
Bau M. Rare-earth element mobility during hydrothermal and metamorphic fluid-rock interaction an d significance of the oxidation state of europium.Chemical Geology,1991,93:219~230.
    Chung S L, Lee TY, Lo C H,et al. Intraplate extension prior to continental extrusion along the Ai lao Shan-Red River Shear Zone. Geology,1997,25(4):311~314.
    Hass J R, Shock E L, Sassani D C. Rare earth elements in hydrothermal systems:Eatimates of standard partial modal thermodynamic properties of aqueous complexes of the rare earth elements at high pressures and temperatures. Geochim. Cosmochim. Acta,1995,59(21):4329~4350
    Klinkhamer G P, Elderfield, Edmond J M et al. Geochemical implications of rare earth element patterms in hydrothermal fluid from mid-ocean ridge. Geochim. Cosmochim. Acta,1994,58(23):5105~5113.
    Michard A, Albar de F, Michard G et al. Rare-earth elements and uranium in high temperatrue s olutions from East Pacific Rise hydrothermal vent field(13N).Nature,1983,303:795~797
    Mills R, Elderfield H. Rare earth element geochemistry of hydrothermal deposits from the active TAG Mount,26° N mid-Atlantic Ridge. Geochim. Cosmochim. Acta,1995,59(17):3511~3524.
    Ohmoto H. Stable isotope geochemistry of ore deposits. In:Valley J.W.,Taylor H.P. and O'Neil J.R.(eds), Stable isotope and high temperature geological processes. Rev. M-ineral.1986, (16):460~491.
    P. Tapponnier, R. Lacassin, et al. The Ailao Shan/Red River metamorphic belt:Tertiary left-lateral shear between Indochina and South China. Nature.1990,343:431~437.
    Schwartz M O. Cadmium in zinc deposits:Economic geology of a polluting element[J]. International Geology Review.2000.42:445~469
    S.-s.Sun, W.F.McDonough. Chemical and isotopic systematics of oceanic basalts:implications for mantle composition and processes[J]. Geological Society, London, Special Publications; 1989; v.42; p. 313~345.
    Sangster D F. Sulfur and lead isotopes in strata-bound deposits. In:wolf K H, ed. Handbook of Strara-Bound and Stratiform Ore Deposits. Elsevier, Amsterdam,1976,2:219~266.
    Sverjensky D A. Europium redox equilibria in aqueous solution. Earth Planet Sci Lett,1984,67:70~78
    Tapponnier P, Mercier J L, Armijo R. On the mechanics of the collision between India and Asia. In: Coward M P, Ries AC, eds. Collision Tectonics. London:Geological Society of London Special Publication,1986,19:115~157.
    Tapponnier P, Molnar P, Armijo R. Propagation ext rusion tectonics in Asia:new insights from simple experiment s with plasticine. Geology,1982,10:611~616.
    Wang P L,Lo Ch, Lee T Y,et al. Thermochronological constraints on two pulses of Cenozoic high-K magmatism in eastern Tibet. Science in China(Series D),1998,46(7):719~729.
    Yin A, Harrison T M, Ryerson F J, Chen W, Kidd W S F,Copeland P. Tertiary st ructural evolution of the Gangdese t hrust system, sout heastern Tibet. J. Geophys.Res.1994,99:18175~18201.
    Yin A, Kong X. Spacing of N2S rift s in Tibet implieslit hospheric ectension. Eos 1997,78, F173.
    Yang Zhenyu,Yin Jinyun,Sun Zhiming,et al. Discrepant Cretaceous Paleomagnetic poles between eastern China and Indochina:a consequence of the extrusion of Indochina. Tectonophysics, 2001,34(1):101~113
    陈梁,孙德瑜,等.兰坪县青甸湾铅锌矿矿床地质[J].云南地质,2009,28(3):280~284.
    戴自希,盛继福,白冶,等.世界铅锌资源的分布与潜力[M].北京:地震出版社,2005
    丁振举,姚书振等.东沟坝多金属矿床喷流沉积成矿特征的稀土元素地球化学示踪.岩石学报[J].2003,19(04),792~798.
    范承钧,张翼飞.云南西部地质构造格局[J].云南地质.1993,12(2):139~181
    范世家,王安建,刘汉斌,等.论兰坪盆地白秧坪铜(钴)矿床成因的氦氩同位素证据[J].地质论评,2006,52(5):628~635.
    范世家.兰坪盆地东、西带铅锌铜多金属成矿作用对比研究[D].中国地质科学院博士论文.2007.
    葛良胜,杨嘉禾,郭晓东等.滇西北地区(近)东西向隐伏构造带的存在及证据[J].云南地质.1999,2:155~167
    管烨,王安建,曹殿华等.云南三江造山带近东西向构造特征及其研究意义[J].地质学报.2004,4:494~499
    管烨,王安建,李朋武,曹殿华等.云南兰坪-思茅盆地中轴构造带的特征及其研究意义[J].中国地质.2006,4:832~841
    韩吟文,马振东,张宏飞,等.地球化学[M].北京:地质出版社,2003.
    何明勤,刘家军,李朝阳,李志明,刘玉平.兰坪盆地铅锌铜大型矿集区的流体成矿作用机制——以白秧坪铜钴多金属地区为例[M].北京:地质出版社.2004.
    侯增谦等.现代与古代海底热水成矿作用[M].北京:地质出版社.2003.
    李迪恩等.闪锌矿的标型特征,形成条件与电子结构[J].矿床地质,1989,3:75~82
    李徽.闪锌矿中杂质元素的特征及地质意义[J].地质与勘探,1986,10:42~46
    李雷,马远等.滇西金矿初步研究[J].有色金属矿产与勘查.1994,6:328~334
    李文昌,莫宣学.西南“三江”地区新生代构造及其成矿作用[J].云南地质.2001,4:333~346
    廖崇高,刘登忠,杨武年等.地质异常理论在兰坪盆地演化中的应用[J].云南地质.2001,20(3):253~259
    林舸,范蔚茗,尹汉辉.中国滇西兰坪—思茅地洼盆地内中轴断裂带的初步研究[J].大地构造与成矿学.1991,1:15~21
    刘家军,翟德高,李志明,等.兰坪盆地白秧坪银铜多金属矿集区中银、钴、铋、镍的赋存状态与成因意义[J].岩石学报,2010,26(6):1446~1460.
    刘家军.兰坪思茅盆地红色碎屑岩建造中铜矿床的陆相喷流作用.贵阳:中国科学院地球化学研究所博士研究流动站1998.1~70
    刘建明,刘家军,顾雪祥.沉积盆地中的流体活动及其成矿作用[J].岩石矿物学杂,1997,16(4):341~352.
    刘俊来,王安建,曹殿华等.三江造山带后碰撞断裂构造带的结构与演化:以新生代剑川—兰坪盆 地为例[J].高校地质学报.2004.4:488~499.
    罗君烈,杨荆州.滇西特提斯的演化及主要金属矿床成矿作用[M].北京:地质出版社,1994,149~239
    马茁卉.我国铅锌资源现状及发展政策建议[J].西部资源,2008,2:21~25.
    牟传龙,下剑.余谦等兰坪中新生代沉积盆地演化[J].矿物岩石.1999,19(3):30~36
    冉崇英,雷文礼,李峰,等.滇中镇西地区铜多金属成矿条件及综合成矿顶测科研总结报告.昆明:昆明工学院地质系.1991.2-1-2~49
    帅开业.兰坪-思茅中新生代盆地成因新解[J].地学前缘.2000,7(4):380
    陶晓风,朱利东,刘登忠等.滇西兰坪盆地的形成及演化[J].成都理工学院学报,2002,29(5):521~525
    涂光炽.我国南方几个特殊的热水沉积矿床.谢家荣纪念文集,地质出版社.1990.
    王安建,高兰,刘俊来,曹殿华,修群业,范世家.论兰坪金顶超大型铅锌矿容矿角砾岩的成因,地质学报.2007,81(7):891~897.
    王国芝,胡瑞忠,王成善,曾允孚.云南金顶超大型铅锌矿床的成矿地质背景.矿物学报,2001,21(4):571~577.
    王江海,尹安,Harrison T M, Grove M,周江羽,张玉泉,解广轰.青藏东缘新生代两类高钾岩浆活动的热年代学研究.中国科学(D),2002,32(7):529~537.
    徐克勤,王鹤年,周建平,等.论华南喷流一沉积块状硫化物矿床[J].高校地质学报,1996,2(3):241~256.
    薛春纪,陈毓川,杨建民等.滇西兰坪盆地构造体制和成矿背景分析[J].矿床地质,2002c,21:36~44.
    薛顺荣.剑川金山桃铅锌矿床特征及成因探讨[J].云南地质,2000,19(1):29~36.
    杨友华,赵准.试论金顶超大型铅锌矿床的形成条件[J].云南地质,1991,10(2):230~240.
    尹汉辉,林舸,范蔚茗.云南地洼盆地演化的深部因素及幔壳复合成矿作用[J].大地构造与成矿学,1990,14(2):113~124
    余谦,牟传龙、王剑等.云南兰坪盆地三叠纪沉积相与古地理演化[J].沉积与特提斯地质,2000,20(2)33~42
    张泰身,和浪涛.兰坪-思茅盆地“中轴断裂”及其对金矿区域成矿的控制.大地构造与成矿学[J].2000,24(S1):63~66
    张中杰;白志明;王椿镛等.三江地区地壳结构及动力学意义:云南遮放-宾川地震反射/折射剖面的启示[J].中国科学:D辑.2005,35(4):314~319
    钟大赉,P.Tapponnier,吴海威等.大型走滑断层——碰撞后陆内变形的重要形式[J].科学通报.1989,34(7):526~529
    钟大赉,丁林,刘福田等.造山带岩石层多向层架构造及其对新生代岩浆活动制约--以三江及邻区为例[J].中国科学D辑.2001,30(Z1):1~8
    钟康惠,唐菊兴,刘肇昌,寇林林,董树义,李志军,周慧文.青藏东缘昌都一思茅构造带中新生代陆内裂谷作用[J].地质学报,2006,9:1296~1311.
    朱创业,夏文杰,尹海生等.兰坪一思茅中生代盆地性质及构造演化[J].成都理工学院学报,1997,24(4)23~30.

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