Metallogenesis and Tectonics of the Russian Far East, Alaska, and ...

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A proximate laatbm c#f C h # d ~naral Zone. ='"drVe c;eo!- BbGb monmnite and syenite (Early Tertiary and Late Crebceol uartz monite 7 7 Earl Tertiary and ~ a t e P W I f KuskokwknOlrw dastic rocks w--=-P Figure 11 1. Vinasale Mountain granitold+elated (porphyry) Au d m . Kuskokwtm Mountains metallogenic belt, Southwestern Alaska. Schematic geabgc map showing location of CerrtreJ h&n~ral Zone. Adapted from Bundtzen (1986), DiMarchi (1993), and Bundtzen and Mler (1W7). Marshall District d thm&WR&W Au Depr)slb, West-Central Alaska A suite of granitoid-rehted Au deposits of thu h&mW distric€ mxur at the Anaoldprmpct tha hssdufWillow Creek in southwestern Alaska (Bun* and Mk, 1997). The depmfs m& of quark- vds which oe~llr in, or neou sheared Late Cretaceous or early Tertiary dd&e sills which inaade the Kophk island-arc tenane (NokIehg end ofhas, 1994c, 1997~). The significant deposits and prospects hchk the Arnold, K&o, and ShlyaProk gold prospects. The Arnold prospsct mnsista drrn 7 - . esstsstw~t-~ mite of low sulfide polymetall~c vbwhich wcain gold in quartz and carborn* gangue. Tho Mdenrinerals, whkb comptk lese khan mepemat of the deposit, 81a dhmnkkd chalcopyrite, molybdenite, galena, and tetrdwdth. Tbe vein system occurs m, or near sheared alaskite sills. A distinctive albite rhyolite die or sill parallels the main vein system. Tbe sills klmk (miy Early Cretaceous) greenslono derived &om tholeiite metabasalt and mebdesite. The dqwit exbda akwg shrike for least 400 maem and ranges from 0.5 to 2 m thick. Abundant carbonate alteration occurs adjacent to the main po1pnehUc veins. Mo avenges about 80 p p in var& Mo anomalies occur in soils. Grab samgles of mks contain up to 97 g/t and 1100 glt Ag. Other significant gol&polymetallic min~tion m he M&l U t include impmhnt lode md essociakd placer gold occurrences at Kako Creek crnd SRtyahok, hut 55 km and 75 km east of the Arnold proqml, respectively (Miller and others, 1998). Both af &he latter prospecis rcmmbla the Donh Creek deposit dewi'bed above, and are spaESalEy related to d l , Late Cretaceous ,sills md dikes which intmde the Koyuhk terpana. Au-Ag-Hb-Sb EpMennat W t 8 , Kuskokwim Mind B.lt Epithed systems of the Kuskokwin Mind Belt are subdivided into three majcw types (Bmdtam and qcr, 11997; Gray and others, 1997): (I) stnrcturally cootrolled (AubHgSb deposits related to altered olivhat: bas& (2) low tempamm Ay-Sb-Hg mind m &ear zones in high level jmrhoils of bY.nisians; and (3) chPloedoay breccias hosted in subaerial volcanic. piles, including stockwark veins aijacent to volcanic caldmw- AkhOPlgh generally poo& classified, the three epithemal deposit types probably cormpand to depbsit models the horspringrs Ail-&, Cox and Singer (1986). C d cpithend, mil §ado epitherPael depc& mdcIs of The structurnlty controIId Au-Sb-Hg depositJ (type 1) are part of a well-studied Hg beh (Sainshury md MacKevett, 1965) which e x W nearly 5500 EEm fi-bm the Red Top mine near Bristol Bay to Mount Joaquin near McGrath. The principle type 1 deposit is the Red DevU Hg-SIs mine near Sleetmute which produced mo~e than 85 peFCeat of the 1.5 Wkm kg ofw Hg
production from the Kuskokwim Mineral Belt, and was the largest mercury mine in Alaska. At Red Devil, high-angle structures cut flysch of the Cretaceous Kuskokwim Group and altered mafic dikes. The fluids tht deposited cinnabar and stibnite utilized faulted mafic dikes as structural conduits; however no clear link exists between dikes and the deposit. Bundtzen and Miller (1 997), Gray and others (1997), and Miller and others (1989) all report which fluid inclusion data from type 1 epithermal deposits in the Kuskokwim Mineral Belt which indicate shallow depths of ore deposition at less than 1,500 bars pressure, and less than 200 C. Gray and others (1997) report radiometric ages ranging from 72.5 to 76 Ma for several deposits. Type 2 Au-Sb-Hg vein deposits include the Dishna River Au-Sb prospect and Glenn and Minnie Gulch prospects, which cut high level plutonic rocks in the Flat area (Bundtzen and others, 1992; Bundtzen and Miller, 1997). During 1998-1999, an important new epithermal Au-Ag deposit (type 3 above) was discovered at the Kaiyah prospect about 125 km southwest of McGrath (Bundtzen and others, 2000). The deposit occurs about 2 km from a curvilinear, faulted contact between the Early Cretaceous flysch of the Yukon-Koyukuk basin and andesite tuff, welded tuff, and rhyodacite domes of the Late Cretaceous and early Tertiary Poison Creek caldera. The volcanic rocks have isotopic ages of 42.5 and 65.2 Ma, and the caldera covers 75 km2 (Bundtzen and Miller, 1997). The deposit occurs in a 4 by 2.5 krn altered area which contains abundant silica alteration, and extensive alunite, jarosite, and sericite alterations. lndividual Au-Ag veins average 30 m thick and extend about 450 m along strike. Anomalous elements are Sb, Hg, As, Te, Pb, Cu, and Bi. Geological and geochemical data suggest that the Kaiyah deposit is a high sulfidation epithermal Au-Ag deposit with a Ag:Au ratio of about 40: 1. Grades range up to 10.8 g/t Au gold and 465 g/t Ag (Bundtzen and others, 2000). Other Significant Deposits in the Kuskokwim Mineral Belt The high grade Au-Bi-Cu skams at Nixon Fork (fig. 1 12), 45 krn, northeast of McGrath, have been developed and mined since the 1920s. The ore deposits occur in irregular, and rich, pipe-like, garnet-epidote-magnetite-gold-copper-skarn which rim a monzonite stock that has a K-Ar isotopic age of 68 Ma. The intrusion cuts Ordovician limestone of the Novi Mountain Formation (Patton and others, 1994). From 1920 to 1999 Nixon Fork Mining Company and previous operators produced 6,2 10 kg Au, and byproduct Bi and Cu from about 128,300 tonnes of ore (Bundtzen and others, 2000). East-Central Alaska Metallogenic Belt of Granitic Magmatism Deposits (Younger, Late Cretaceous and Early Tertiary Part; Belt ECA) East-Central Alaska and Northern Canadian Cordillera This major, long, extensive, and complex metallogenic belt of Late Cretaceous and early Tertiary granitic-magrnatism- related deposits (belt ECA) (fig. 103; tables 3,4) occurs in east-central Alaska and the western Yukon Territory (Nokleberg and others, 1995a). The significant deposits are mainly various W skarn, porphyry Cu-Mo deposits, polymetallic vein, Sn greisen and vein, and Sb-Au vein deposits in the northern and eastern Yukon-Tanana terrane (table 4). Described below are the major Casino and Taurus porphyry Cu-Mo deposits, and the Road Metal tourmaline-topaz-quartz sulfide greisen deposit. The East-Central Alaska part of the belt contains a variety granitic magmatism deposits which are hosted in Late Cretaceous and sparse early Tertiary granitoids which intrude the northern and eastern Yukon-Tanana terrane (Table 4). Major deposits are: (1) a W skam deposit at Salcha River (possibly mid-Cretaceous); (2) porphyry Cu-Mo deposits at Mosquito, Asarco, Taurus, and Casino; (3) a Sn greisen deposit at Ketchem Dome; (4) Sn greisen and Sn vein deposits at Ketchen Dome and Lime Peak; and (5) a felsic-plutonic U deposit at Roy Creek (former Mount Prindle). For deposits in groups (1) to (4), the host rock of the Yukon-Tanna terrane consists of metamorphosed and penetratively deformed, middle Paleozoic and older, quartz- metasedimentary, sparse metavolcanic, and rare middle Paleozoic metagranitoid rocks (Foster and others, 1987). For the deposits in group (5), the granitoid rocks hosting the felsic-plutonic U deposits intrude a sequence of weakly deformed, quartz-rich sandstone, grit, shale, and slate, containing probable Early Cambrian fossils, which form part of the Wickersham passive continental margin terrane (Jones and others, 1987). Yukon Territory part of the belt contains porphyry Cu-Mo deposits in the Cannacks area. Casino Porphyry Cu-Mo-Au Deposit The large Casino (Patton Hill) porphyry Cu-Mo-Au deposit in the Carmacks area, Yukon Territory, is hosted in a breccia pipe and associated porphyritic dacite and granite of the Casino Intrusive Complex which has a K-Ar isotopic age 7 1.3 Ma, which intrudes the Early Jurassic Klotassin batholith. The deposit occurs in the center of the complex and consists of a central, conical breccia pipe, fine-grained quartz monzonite, intrusion breccia, and plagioclase porphyry intrusions (EMR Canada, 1989; Mining Review, 1992; Sinclair, 1986; Northern Miner, December 6,1993; Bower and others, 1995). An innermost zone of potassic alteration is associated with hypogene sulfides, and contains superimposed phyllic and pyrite alteration, and weakly-developed, peripheral propylitic alteration. Supergene minerals are chalcocite, digenite, and covellite which occur as replacements of hypogene sulfides. A 70-m-thick, Au-bearing leached cap overlies a well developed supergene enrichment blanket. Estimated reserves are: (1) for a combined Au-oxide zone in the leached cap and an copper-oxide supergene zone, 28 million tonnes grading 0.68 g/t Au, 0.11% Cu, and 0.024% Mo; (2) for a sulfide supergene zone, 86 million tonnes grading 0.41 g/t Au, 0.43% Cu, and
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I EUSGS science Ior a changing wwld
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CONTENTS Abstract .................
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5 : 3 . Kedon metall lo genic Belt
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Parson and Brisco Barite Vein and G
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Overview ..........................
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Chepak Granitoid-Related Au Deposit
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Origin of and Tectonic Controls for
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Au-Ag Epithermal Vein Deposits Asso
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Metallogenesis and Tectonics of the
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and Byalobzhesky (1996). A volume c
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1,079 significant mineral deposits
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Acknowledgements We thank the many
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0 --mmm=oRuwrrrur ommmmarUaAll NEr-
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Figure 3. Generalized map of mtljor
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Archean granulite facies metamorphi
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Figure 5. Oroek sediment-h section
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1 a a - --rich sandstone ~b-Qmg@ner
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Origin of and Tectonic Setting for
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occur in clastic and impure carbona
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Figure 7. Sullivan sedimentary-exha
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I 1997a, b, 1998). The massive sulf
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Ma which locally form extensive plu
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Figure 10. Gerbikanskoe vdcanogenic
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from crystalline basement of craton
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Figure 13. Howards Pass sedknenWy e
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McLean Arm Porphyry Cu-Mo District
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[..'......I Surfia'al deposits (Hol
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Figwe 16. GeneraCied map of major M
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.- *.-* *. . - - ---- -A - EARLY MI
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Metallogenic Belt Formed During Col
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several tens of meters to 1,300 m l
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Goldfarb (197) who interprets that
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WTF and Red Mountain Kuroko Massive
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interpreted by and as part of a ext
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Mount Sicker Metallogenic Belt of K
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interpreted as vents. The deposit c
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hosted in the Yarkhodon subterrane
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origin of the younger Triassic(?) B
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Mississippian age of mineralizalioi
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Monger and Nokleberg, 1996; Noklebe
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1997a, b). Most of the magnesite an
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FL - Finlayson Lakm FR-FmLake LI -
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disseminations in chert, disseminat
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U F~gure 32 GemMzed m p of mejw -ni
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terrane, and by the Stikine Assembl
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Metallogenic-Tectonic Model for Lat
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. I . r ; 4 ~ (9) During subduction
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Eastern Alaska Range Metallogenic B
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individual flows range from 5 cm to
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occurrence of turbiditic clastic ro
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along the with tectonically-related
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: m- 3- w43 k M- u m u~u) mtl 'M~!A
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island-arc volcanic rocks of the Ni
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-- - //// EpldoW Figure 41. Nickel
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(TC), and Toodoggone (TO) belts whi
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(4) The Angayucham Ocean (Kobuck Se
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lueschist units and the McHugh Comp
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Figure 46. Lawyers Au-Ag epitiefmel
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(5) The Angayucham Ocean (Kobuck Se
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Figure 49 Generaltzed map Of mbjm L
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continental-margin terranes which w
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Pokrovskoe Au-Ag Epithermal Vein De
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Granite-porphm and wanits W e ~~ hl
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subordinate adularia, dolomite, cel
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shale, basalt, plagiorhyolite, silt
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ocks and serpentinite which occur a
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interpreted as forming in the Juras
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Fault / Figure 57. Bond Creek and O
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Klukwan-Duke Metallogenic Bett of M
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tonnes of ore mined between 1967 an
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Cariboo Metallogenic Belt of Au Qua
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Sheep Creek Au-Ag Polymetallic Vein
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---. .% of the North American Conti
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- OwiapaasembC Cmhmmmand Cemmcl. an
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in the west-central part of the Rus
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for about 850 krn (ZalishshaL ad oh
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Stanovoy Metallogenic Belt of Grani
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Goryachev, 1995, 1998, 2003) consis
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Altinskoe, Aragochan, Dalnee, Dokhs
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comprises up to 70-80% in some ore
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The Au quartz vein deposits are int
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leucogranite plutons form large, ho
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+ , . Diorite phyry dike (Early ~ta
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- . --- Origin of and Tectonic Cont
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Britannia Metallogenic Belt of Kuro
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Specific Events for Late Early Cret
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Figure 73. Solnechnae Sin qu- ~d~ n
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- Origin of and Tectonic Controls f
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Nome Metallogenic Belt of Au Quartz
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quartz vein deposits of the Souther
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Selwyn Plutonjc Suite. The host roc
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along the western end in the Eagle
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101 Ma (K.M. Dawson, unpublished da
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I Bayonne Metallogenic Belt of Porp
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., (VV) belts. These zones and beb
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I (2) The East Sikhote-Alin (es) co
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Metallogenic Belt Formed in Late Me
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The Pb-Zn polyrnetallu: vein depb a
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olistolith. The deposit is currentl
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the core of the veins, chlorite, Mn
Page 224 and 225: Tayozhnoe Ag Epithermal Vein Deposi
Page 226 and 227: Figure 90. lskra deposit Sn polyrne
Page 228 and 229: - El (Late ~re&ceous) I+ we cmm=s)
Page 230 and 231: Figure 93. Mnogovershinnoe AMq @pWw
Page 232 and 233: immed by wehrlite, olivine-magnetit
Page 234 and 235: Eastern Asia-Arctic Metallogenic Be
Page 236 and 237: which would be hosted in the early
Page 238 and 239: Etandzha Porphyry Cu-Mo and Muromet
Page 240 and 241: 0- / Fadt . . Au veins and pods Fig
Page 242 and 243: Sentachan Clastic-Sediment-Hosted A
Page 244 and 245: I I I Undifferentiated vdcanic and
Page 246 and 247: .r . : . -d ' . . ,, $44 . assembla
Page 248 and 249: closure, the Chukotka supertca&c wa
Page 250 and 251: - Mgh anglefau#or prsminant Fitwar
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Page 254 and 255: Figure 101 8. Ke~ecolt &4W d KemwaI
Page 256 and 257: Figure 103. Generalized map of majo
Page 258 and 259: metallogenic belt (SP) which contai
Page 260 and 261: Eastern Asia-Arctic Metallogenic Be
Page 262 and 263: Valunistoe Au-Ag Epithermal Vein De
Page 264 and 265: Lost River Sn-W Skarn and Sn Greise
Page 266 and 267: Wheeler Creek, Clear Creek, and Zan
Page 268 and 269: Au veln,and hots spring deposits at
Page 270 and 271: Chicken Mountain Cu-Au Deposit The
Page 272 and 273: Chip sample location - Fault / Cont
Page 276 and 277: 0.03 1% Mo; and (3) for a hypogene
Page 278 and 279: others, 1994c. 1997~). The granitoi
Page 280 and 281: Cross section - - South greisen zon
Page 282 and 283: Origin of and Tectonic Controls for
Page 284 and 285: 198 1). The mine at the deposit pro
Page 286 and 287: Beatson (Latouche) and Ellamar Bess
Page 290 and 291: CRETACEOUS Mount Leonard St& gueYtr
Page 292 and 293: n pJ pRanens. Pd-dc i3 Meeomic .---
Page 294 and 295: Figure 120. Huckleberry porphyry Cu
Page 296 and 297: 0.15% Cu (ox), 0.127 g/t Au, and 0.
Page 298 and 299: Zone are 188 million tonnes grading
Page 300 and 301: Kitsault (B.C. Moly) Porphyry Mo De
Page 302 and 303: million tonnes grading 0.42% Cu, 0.
Page 304 and 305: extension. The Coryell Suite is int
Page 306 and 307: elated deposits. Forming in the bac
Page 308 and 309: Metallogenic Belts Formed in Tertia
Page 310 and 311: Hg Deposits Hg deposits occur throu
Page 312 and 313: Maletoivayam Sulfur-Sulfide Deposit
Page 316 and 317: (5) A major orthogonal junction for
Page 318 and 319: Metallogenic Belts Formed in Tertia
Page 320 and 321: occur in these tabular, altered sil
Page 322 and 323: summarlzed above are used by analog
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the Aleutian volcanic belt. The Yak
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metamorphism, anatectic granites, a
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References Cited Abbott, G., 1981,
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Society of America Abstracts with P
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Sciences, North-Eastern lnterdiscip
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Burgoyne, A.A., 1986, geology and e
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Canadian Cordillera, Yukon-northeas
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the Koryak Highlands: Transactions
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during 1984: U.S. Geological Survey
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Northeast Scientific Intergrated Re
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House, G.D., and Ainsworth, B., 199
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International Field Conference in V
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lithosphere in flood basalt genesis
Page 350 and 351:
MacKevett, E.M., Jr., 1978, Geologi
Page 352 and 353:
Miller, M.L., Bundtzen, T.K., and K
Page 354 and 355:
Nekrasov, I.Ya., 1995, Genetic type
Page 357 and 358:
Pakhomova, V.. Silyanik, V., Popov,
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Pollack, John, 1997, Summary report
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1993: British Columbia Geological S
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Schroeter, T.G., 1987, Golden Bear
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Geology of the Liese zone, Pogo pro
Page 367 and 368:
Colorado, Geological Society of Ame
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lnstitute of Mining and Metallurgy
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Anorthosite apatite-Ti-Fe Gabbroic
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TABLE 2. Summary of correlations an
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TABLE 2. Summary of correlations an
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9! TABLE ectonic environment of Pro
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(Abbreviation) Rassokha (RA) Dzhard
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Metallogenic Belt (Abbreviation) Be
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Major Mineral Deposits Types. Envir
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(Abbreviation) Guichon (GU) I Belt
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Major Mineral Deposits Types. Envir
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(Abbreviation) (Significant Mineral
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(Abbreviation) Adycha-Taryn (EAAT)
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~etallo~enic Belt Major Mineral Dep
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Metallogenic Belt (Abbreviation) Ca
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TABLE 4. Significant lode deposits,
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Mineral Deposit Model Major Metals
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Deposit Name Mineral Deposit Model
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Deposit Nmme Mineral Deposit Model
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p;. ;A'..* Deposit Name Mineral Dep
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De~osit Name Mineral Deposit Model
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