古生代新元古代晚期造山型金矿课件.ppt

1、Part III)Paleozoic/late Neoprot Orogenic Au古生代古生代/新元古代晚期造山型金新元古代晚期造山型金矿矿Terra Australis OrogenTerra Australis 造山带造山带Series of N-S Pz fold belts一系列南北向古生代褶皱带一系列南北向古生代褶皱带80 Moz Au 80百万盎司金百万盎司金Veining&defm=ca.440 Ma脉和变形脉和变形=大约大约440百万年百万年LachlanThomsonHodgkinson-Broken RiverNew England(Permo-Tr)The Tasma

2、nides inEastern Australia:Au-Rich Pz Fold Belts&Younger Cover 澳大利亚东部的塔斯曼域：富金澳大利亚东部的塔斯曼域：富金的古生代褶皱带和盖层的古生代褶皱带和盖层Lode Gold Deposits,Tasman Fold Belt塔斯曼褶皱带中的造山带型金矿床Westland,South Island南部岛屿，西岸南部岛屿，西岸Eastern Gondwana东冈瓦纳东冈瓦纳PALEOZOIC ANTARCTICA古生代南极洲古生代南极洲EASTERN CORDILLERA:A POTENTIAL WORLD-CLASS OROGEN

3、IC GOLD PROVINCE?东东科迪科迪嘞嘞拉：拉：一个潜在的世界一个潜在的世界级级的造山型金的造山型金矿矿省？省？Paleozoic Gold 古生代金矿古生代金矿7 Moz prod.100 Moz100 Moz250 Moz150 MozGOLD DEPOSITSOF ARABIAN-NUBIAN SHIELDARABIAN-NUBIAN地盾金地盾金矿矿100 Moz in ancient times储储量曾达量曾达100 MozAlmost all orogenic gold几乎全几乎全为为造山型金造山型金矿矿Microcontinents off Rodinia and Gon

4、dwanaDistinct ore-forming events during 600-250 Ma growth of Asia古特提斯洋古特提斯洋Rodinia和和Gondwana古古陆陆之外的微之外的微陆块陆块600-250 Ma独特的成独特的成矿矿事事件件亚亚洲大洲大陆陆的生的生长长中中亚亚造山造山带带Tuva-Mongol ArcSiberianCratonEast Sayan350 MaKazakhstania Sukhoi Log Irokinda KamennyWest SayanYenisei RidgeTransbaikalTainskyZun-OspaBaroon-Hol

5、baZun-HolbaBaikal-Bodaibofault zoneSovetskoeEldoradoOlympiadaUdereiskoeOb-Zaisan OceanJunggarBalkhashOceanBaikal-Patom passive marginOlokit terraneBaikal-Muya terraneGargan BlockNFuture extent of thepost-ore Angara-Vitimbatholith(340-270 Ma)Early-Middle PaleozoicOn Craton Margins of Siberia=Oldest G

6、old in Asia位于西伯利位于西伯利亚亚克拉通克拉通边边缘缘的早中古生代金的早中古生代金矿矿是是亚亚洲最老的金洲最老的金矿矿Olympiada760-720 Ma?,512 Ma?East Sayan500-450 MaBaikal450-440 Ma?345 Ma?Tectonic Setting for Orogenic Gold造山带金矿构造背景造山带金矿构造背景古特提斯洋古特提斯洋E.Pz.orogenic gold deposits of NW Kazakhstan=accretion onto Kazakstania哈沙克斯坦西北部早古生代造山型金哈沙克斯坦西北部早古生代造山

7、型金矿矿床床=哈哈萨萨克大克大陆陆的增生作用的增生作用(after Windley et al,2007;Seltmann,2010)Microcontinents off GondwanaDistinct ore-forming eventsChina Cratonic Blocks about 350 MaSouth Margin of North China as it Migrated Across the OceanW.Qinling gold province=110-103oE(400-300 Ma collision)Qilian gold province=only alon

8、g NW edge(380-360 Ma collision)Enkelmann et al,2007Qilian Belt 祁祁连带连带Au in N Qilian Ord vx and N Qaidam Mesoprot phyllite 北祁北祁连连奥陶奥陶纪纪yx和柴北和柴北缘缘中元古代千枚中元古代千枚岩中的金岩中的金Superterrane accreted ca.380-360 Ma(Xiao et al,2009)超超级级地地块块增生增生Hanshan=60 t Au,220 Ma(Mao et al,2000);Tanjianshan=50 t Au,275 Ma(Zhang

9、et al,2009)西秦岭金西秦岭金矿带矿带（210-170 Ma Au）Yangshan Gold Belt 阳山金阳山金矿带矿带Anba deposit,281 t Au(largest in China?)Both disseminated and vein ores in Devonian phylliteGeochron conflicting from 197-51 Ma安安坝坝金金矿矿，281吨金（中国最大？）吨金（中国最大？）都是位于泥盆都是位于泥盆纪纪千枚岩中的千枚岩中的细细脉侵染脉侵染状状矿矿体体地地质质年代学年代学变变化于化于197-51 MaPERMO-TR.NAPA

10、NJING BASIN 二叠-三叠纪南盘江盆地 Carlin-like deposits in SW China and NE Vietnam中国西南部及中国西南部及Vietnam东东北部北部类类卡林型卡林型矿矿床床Dian-Qian-Gui province滇滇-黔黔-贵贵省省Au-Sb-Hg ores in Perm-Tr domes with carbonate coresAu-Sb-Hg矿矿位于核位于核部部为为碳酸碳酸盐盐的二叠的二叠-三叠三叠纪纪穹窿中穹窿中Ores perhaps 200 Ma成成矿矿于于约约200 MaCentral Asian Orogenic Gold Gia

11、nts中亚造山带超大的造山带型金矿中亚造山带超大的造山带型金矿Permian orogenic gold belts 二叠二叠纪纪造山型金造山型金矿带矿带2 major belts of orogenic Au:Kalba and South Tien Shan两条主要的造山型金两条主要的造山型金矿带矿带：Kalba和南天山和南天山Geologic reconstruction based on Filippova et al.(2001)and Yakubchuk(2002).L.Pz.orogenic gold deposits of NE Kazakhstan=accretion ont

12、o Siberia(after Windley et al,2007;Seltmann,2010)Kalba Prov.向西伯利向西伯利亚亚的增生作用造就的增生作用造就了哈了哈萨萨克斯坦克斯坦东东北部晚古生北部晚古生代造山型金代造山型金矿矿床床after Yakubchuk et al(2005)Most outboard deposits:ca.285 Ma for 5000 kmUzbekistan orogenic gold 乌兹别乌兹别克斯坦造山型金克斯坦造山型金矿矿after Drew et al(1998);Yakubchuk et al(2005)Muruntau(W.Tien

13、Shan)Muruntau（西天山）（西天山）Early Pz carbonaceous siltstone;dissem.pyrrhotite;20-50 ppb Au?Mid Pz metamorphism;carb platform to NLate Carb.-Permian magmatism/defmtn/gold(285 Ma)175 Moz Au;3.5-5 g/t;PGE produced早古生代含碳粉砂岩;浸染状磁黄铁矿 20-50 ppb Au（？）古生代中期变质作用，向北为碳酸盐台地晚石炭二叠纪岩浆活动及变形作用，金矿形成(285 Ma)175百万盎司金；3.5-5 g

14、/t;还有PGEApproximately 6 kilometresMURUNTAU:Why So Large?穆穆龙龙套：套：为为何如此之大？何如此之大？Approximately 6 kilometresApproximately 300m deepMajor jog in South TS-Central TS suture?中南天山中南天山缝缝合合带带的主要交的主要交汇处汇处？Carbonate platform rocks(e.g.,Carlin processes)?碳酸碳酸盐盐台地（如卡林型？）台地（如卡林型？）Besopan sediments originally gold

15、rich?沉沉积围积围岩富金？岩富金？Kumtor(E.Tien Shan)东天山东天山Kumtor矿矿Vendian carbonaceous phyllites(Dzhetymtau Fm)Vendian 含碳千枚岩Late Pz mineralization (297-284 Ma argon dates)晚古生代矿化（297-284 Ma 氩氩年龄）Veins,stockworks,breccia 脉形，网脉型，角砾岩型570 t Au,3.58 g/tAlong major offset&sheared batholith margin 沿主要断裂带及剪切变形的岩基边缘分布Fine

16、gold in pyrite黄铁矿中的纯金Hg-Sb depositXafter Sengor and Natal in 1996Hg-Sb Lodes Southern Tian Shan南天山南天山Hg-Sb矿矿脉脉 Late Pz orogenic belts between Angaran/Yili/Tarim cratons Angaran、Yili和和 Tarim 克拉通之间的克拉通之间的晚古生代造山带晚古生代造山带 Altay Shan:Dev Fe-Cu-Zn VMS,Carb-Perm orogenic Au,placers 阿尔泰山：泥盆纪阿尔泰山：泥盆纪Fe-Cu-Zn

17、VMS型，石炭型，石炭-二叠造山带型金二叠造山带型金矿、砂金矿矿、砂金矿 W Junggar:L.Carb orogenic Au 西准葛尔：晚石炭造山带型金矿西准葛尔：晚石炭造山带型金矿 E.Junggar:E.Carb epithermal,Carb-Perm orogenic Au东准葛尔：早石炭浅成热液，石炭东准葛尔：早石炭浅成热液，石炭-二叠造山带型金矿二叠造山带型金矿 Tian Shan:Carb-Perm epithermal,porphyry,&replacement 天山：石炭天山：石炭-二叠浅成热液，斑岩型和交代型矿床二叠浅成热液，斑岩型和交代型矿床Phanerozoic

18、Goldfields 显显生宙采金区生宙采金区Precambrian Orogenic Gold 前寒武前寒武纪纪造山型金造山型金矿矿BoringBillion Granite(30%)-greenstone(10%);high-grade gneiss terrains(60%)花岗岩花岗岩(30%)绿岩绿岩(10%);高品位片麻岩地体中高品位片麻岩地体中(60%)Greenstone belts=broad greenschist facies 绿岩带广泛的绿片岩相绿岩带广泛的绿片岩相 Plate tectonics(plume-driven?)vs.anorogenic tectonic

19、s;lateral vs.vertical growth 板块构造（地幔柱驱动？）还是非造山；侧向生长还是垂向生长板块构造（地幔柱驱动？）还是非造山；侧向生长还是垂向生长 Crustal heat production=2x-4x present 地壳热产率是目前的地壳热产率是目前的24倍倍 Tectono metamorphic ages decrease with structural level 构造变质年龄随构造层下降而减少构造变质年龄随构造层下降而减少 Late Archean=50%cont.crust 晚太古代：晚太古代：50大陆地壳大陆地壳ArcheanGold Preserv

20、ed in Cratons克拉通中保存克拉通中保存的太古宙金矿的太古宙金矿 NA/Greenland+/-central Australia,Africa/SA.N.Asia 63%gneiss,12%plutonic,25%metasupracrustal(mostly gs)Supracrustal=turbidites and greestone belts(Churchill,Guyanas,Birimian)Stable shelf facies;uplift and erosion of shelves/Archean cratons Paleoproterozoic=25%con

21、t.crustPaleoprot.Gold古元古代古元古代金金矿矿after Zhao et al.(2004),Teixera et al.(2007)Paleoprot.Orogenic Au(2.1-1.8 Ga)早元古造山带型金矿早元古造山带型金矿Cratonization=Buoyant SCML克拉通化克拉通化=上浮的次大上浮的次大陆陆岩石圈地幔岩石圈地幔SCLM depleted in Fe&Al,so lighter than surrounding mantle SCLM亏损亏损Fe和和Al，因此比周，因此比周围围的地幔的地幔轻轻SCLM has melt-depleted

22、peridotite buoyancy so balances isostatic equilibrium(i.e.,still dense enough to prevent significant uplift)TECTONIC RECONSTRUCTION OF RODINIA:EVIDENCE OF PHANEROZOIC-STYLE PLATE TECTONICS BY 1.7 Ga BUT NO GOLDRodinia超大超大陆陆重建：重建：类类似似显显生宙板生宙板块块运运动动的的证证据（据（1.7 Ga），但没有形成金），但没有形成金Precambrian Orogenic Gold前寒武纪造山带金矿前寒武纪造山带金矿BoringBillion 乏味的乏味的10亿年亿年Phanerozoic Goldfields显生宙金矿田显生宙金矿田TEMPORAL DISTRIBUTION OF OROGENIC GOLD DEPOSITS:A STRONG REFLECTION OF TECTONIC AND LITHOSPHERIC EVOLUTION造山型金造山型金矿矿的的时间时间分布：与构造及岩石圈演化密切相关分布：与构造及岩石圈演化密切相关