USGS Professional Paper 1697 - Alaska Resources Library

More documents

Recommendations

Info

68 Metallogenesis and Tectonics of the Russian Far East, <strong>Alaska</strong>, and the Canadian Cordillera sedimentary rocks of the North American Craton Margin. The deposits exhibit characteristics similar to Southeast Missouri Pb-Zn deposits in the Robb Lake metallogenic belt of Southeast Missouri Pb-Zn deposits (described herein) and to the Gataga metallogenic belt of SEDEX deposit (described herein). Sulphur isotope analyses exhibit heavy values for barite sulfur in all three metallogenic belts (K.M. Dawson, unpublished data, 1995). These data and a similar geologic setting suggest a genetic relation between the two deposit types and three metallogenic belts. A similar rifting origin is interpreted for all three metallogenic belts. The rifting is interpreted as occurring during the Late Devonian and Early Mississippian rifting event when the Yukon-Tanana and Kootenay metamorphosed continental-margin terranes separated from the North American Craton Margin (Nokleberg and others, 1994c, 1997c, 2000; Monger and Nokleberg, 1996). During the rifting, volcanism, plutonism, related hydrothermal activity, and sedimentary exhalations occurred in the North American Craton Margin and in the Yukon-Tanana and Kootenay terranes (Paradis and others, 1998). Gataga Metallogenic Belt of Zn-Pb-Ag-Ba SEDEX Deposits (Belt GA) Northern British Columbia The Gataga metallogenic belt of Zn-Pb-Ag-Ba SEDEX deposits (fig. 17; tables 3, 4) occurs in northeastern British Columbia. The deposits are hosted in basinal sedimentary strata of the Kechika Trough, a southeastern extension of Selwyn Basin (Fritz and others, 1991). The belt contains eight significant deposits and extends for 180 km southeastward from Driftpile Creek to Akie River. The deposits are localized in inferred euxinic subbasins in a structurally controlled trough that was partly flanked by carbonate reefs (MacIntyre, 1982, 1998). The significant deposits are at Akie, Cirque (Stronsay), and Driftpile Creek (Saint, Roen; table 4) (Nokleberg and others 1997a,b, 1998). The deposits and host rocks are part of a sequence of Late Devonian (Famennian) turbiditic shale and cherty argillite of the Earn Group (Pigage, 1986; Paradis and others, 1998). Cirque (Stronsay) Deposit The Cirque (Stronsay) Zn-Pb-Ag-Ba SEDEX deposit (fig. 28), the largest in the Gataga belt, consists of stratiform, laminar banded, massive barite with pyrite, galena, and sphalerite that occur in turbidite shale, chert, and cherty argillite of the Late Devonian Gunsteel Formation (Jefferson and others, 1983; Gorzynski, 1986). The host rocks are siliceous and contacts between sulfide bodies and sediments are sharp. The deposit forms a 300 by 1000 m tapering, wedge-shaped lens that is about 10 to 60 m thick. The Cirque and adjacent South Cirque deposits contain estimated reserves of 52.2 million tonnes grading 8 percent Zn, 2 percent Pb, and 47 g/t Ag (Mining Review, 1992). Driftpile Creek SEDEX Zn-Pb-Ag-Ba Deposit The three sulfide bodies at the Driftpile SEDEX Zn-Pb- Ag-Ba deposit consist of stratiform pyrite, sphalerite, galena, Cirque Deposit (surface projection) South Cirque Deposit (surface projection) SW Gunsteel Formation Porcellanite Siliceous shale Akie Formation (shale) Road River Group Map Earn Group Warneford Fm. Akie Fm. Gunsteel Fm. Barite / Pyrite Road River Group Shale, siltstone, limestone, chert Normal fault Thrust fault 0 1 km 0 Cross section Mineral Facies Baritic Pyritic Laminar pyrite Contact NE 200 m Contact Normal fault Thrust fault Figure 28. Cirque (Stronsay) sedimentary-exhalative Zn-Pb-Ag- Ba deposit, Gataga metallogenic belt, Canadian Cordillera. Schematic map and cross section. Adapted from Jefferson and others (1983). See figure 16 and table 4 for location.
and barite in siliceous black turbiditic shale of Famennian (Late Devonian) age (Paradis and others, 1998). The deposit has estimated reserves of 18.1 million tonnes grading 2.38 percent Zn+Pb (Insley, 1991; Paradis and others, 1995). The sulfide bodies occur in three stratigraphic levels in the Gunsteel Formation of the Earn Assemblage in different thrust-bounded panels. The host sedimentary rocks are interpreted as part of a Devonian-Mississippian clastic wedge. Origin of and Tectonic Setting for Gataga Metallogenic Belt The SEDEX Zn-Pb-Ag-Ba deposits of the Gataga metallogenic belt are interpreted as forming during deposition of basinal clastic rocks of the Earn Assemblage during the early to late Famennian over a time span of not more than 7 million years. This relatively brief episode occurred during or immediately after a period of continental-margin arc formation and subsequent rifting of the North American Craton Margin in the early Mississippian (Paradis and others, 1998). The rifting is interpreted to have influenced sedimentation and volcanism in the Yukon-Tanana and Kootenay terranes (Nokleberg and others, 1994c, 1997c; Monger and Nokleberg, 1996; Nokleberg and others, 2000). The SEDEX deposits of the Gataga metallogenic belt are interpreted as forming during a relatively brief period immediately after rifting (Paradis and others, 1998; this study). However, other metallogenic belts containing Devonian-Mississippian SEDEX deposits are interpreted as forming over a longer age range, from Frasnian (early Late Devonian) at Macmillan Pass to Tournasian (Early Mississippian) in the Cassiar terrane. Robb Lake Metallogenic Belt of Southeast Missouri Zn-Pb Deposits (Belt RL), Northern British Columbia The Robb Lake metallogenic belt of Southeast Missouri Zn-Pb deposits occurs in northern British Columbia (fig. 17; tables 3. 4) (Nokleberg and others, 1997b, 1998; Nelson and others, 2002) and is hosted in the Proterozoic to Devonian passive continental units of the Rocky Mountains, which constitute part of North American Craton Margin. The Southeast Missouri Pb-Zn deposits in the Robb Lake metallogenic belt occur in secondary breccias of either solution or tectonic origin in folded dolostones mainly of the Silurian and Devonian Muncho-McConnel Formation (Taylor and others, 1975; Nelson and othes, 2002). Occurrences also are located in the underlying Silurian Wokkpash and overlying Devonian Stone,Dunedin, Pine Point, and Slave Point Formations (Macqueen and Thompson, 1978; Nelson and others, 1999; Paradis and others, 1999). The significant deposit is at Robb Lake. Robb Lake Southeast Missouri Zn-Pb Deposits The Robb Lake deposit consists of sphalerite, galena and pyrite that occur primarily in tabular and lenticular zones parallel to bedding in dolomite collapse breccias of the Silurian and Middle and Late Devonian Metallogenic Belts (387 to 360 Ma; figures 16, 17) 69 Devonian Muncho-McConnel Formation (EMR Canada, 1989; Dawson and others, 1991; Mining Review, 1992; Nelson and others, 2002). The deposit occurs on the west limb and crest of a large south plunging anticline. The deposit occurs in an 8 km 2 area, and consists of a series of interconnected, bedding-parallel and crosscutting breccia bodies with a matrix of dolomite, sphalerite, galena, pyrite, quartz, calcite, and pyrobitumen, and peripheral veins and stockwork. (Nelson and others, 2002). Estimated reserves are 7.1 million tonnes grading 4.7 percent Zn and 1.5 percent Pb (Mining Review, summer, 2000). A significantly larger, but less defined resource for the district and belt is an estimated 20.1 million tonnes grading 5.1 percent combined Pb and Zn (Dawson and others, 1991). Origin of and Tectonic Controls for Robb Lake Metallogenic Belt The southern part of the Robb Lake metallogenic belt occurs along a Devonian carbonate facies front in shales of the Besa River Formation to the west for 250 km, extending from Mount Burden on the south to the CTV and DODO deposits near Tuchodi Lakes on the north. The stratigraphic setting for these occurrences, which consists of a carbonate front adjacent to the major Great Slave Lake Basin, is interpreted as analogous to that at Pine Point (Nelson, 1991). Some occurrences in the northern part of the Robb Lake metallogenic belt contain fluorite, barite, and pyrobitumen and are poor in sphalerite, galena, and pyrite. This feature suggests continuity with the southern end of the Liard metallogenic belt of Southeast Missouri Ba-F deposits, which occur in similar Devonian host rocks (Nelson and others, 2002). The timing of mineralization is poorly constrained but is interpreted as preearly Tertiary (pre-Laramide) on the basis of rotated geopetal structures (Manns, 1981) or as Devonian or Missippian on the basis of isotopic studies (Nelson and others, 2002). The Robb Lake metallogenic belt exhibits characteristics similar to the Liard metallogenic belt of Southeast Missouri(?) Ba-F deposits (described above) and to the Gataga Lake metallogenic belt of SEDEX deposit (described above). Sulphur isotope analyses exhibit heavy values for barite in all three metallogenic belts (K.M. Dawson, unpub. data, 1995). These data and a similar geologic setting suggest a genetic relation between the two deposit types and three metallogenic belts. A similar rifting origin is interpreted for all three metallogenic belts. A major period of Late Devonian and Early Mississippian rifting along the North American Craton Margin is interpreted with rifting away of the Yukon-Tanana and Kootenay continental-margin terranes and formation of the Robb Lake and coeval metallogenic belts (Nokleberg and others, 1994c, 1997c; Monger and Nokleberg, 1996; Nokleberg and others, 2000). Nelson and others (2002) propose a somewhat contrasting interpretation of back-arc and intra-arc spreading, and exhalative activity for the genesis of the Robb Lake and related, coeval metallogenic belts. This back-arc and intra-arc spreading would be coeval with the slightly older Kootenary arc as interpreted by Nokleberg and others (2000).
Page 1 and 2:
USGS Prepared in collaboration with
Page 3 and 4:
U.S. Department of the Interior Gal
Page 5 and 6:
iv Hart River SEDEX Zn-Cu-Ag Deposi
Page 7 and 8:
vi Specific Events for Middle Throu
Page 9 and 10:
viii Metallogenic Belts Formed Duri
Page 11 and 12:
x Origin of and Tectonic Controls f
Page 13 and 14:
xii Toodoggone Metallogenic Belt of
Page 15 and 16:
xiv Slate Creek Serpentinite-Hosted
Page 17 and 18:
xvi Left Omolon Belt of Porphyry Mo
Page 19 and 20:
xviii Origin of and Tectonic Contro
Page 21 and 22:
xx Chukotka Metallogenic Belt of Au
Page 23 and 24:
xxii Plutonic Rocks Hosting East-Ce
Page 25 and 26:
xxiv Skeena Metallogenic Belt of Po
Page 27 and 28:
xxvi Bee Creek Porphyry Cu Deposit
Page 29 and 30:
xxviii 36. Wellgreen gabbroic Ni-Cu
Page 31 and 32:
xxx 87. Partizanskoe Pb-Zn skarn de
Page 33 and 34:
Metallogenesis and Tectonics of the
Page 35 and 36:
format (Nokleberg and others, 1996)
Page 37 and 38:
logenesis of the region (1) subduct
Page 39 and 40:
Subterrane—A fault-bounded unit w
Page 41 and 42:
dilemma consists of two conflicting
Page 43 and 44:
2 to 20 m thick. A related dolomite
Page 45 and 46:
Lantarsky-Dzhugdzhur Metallogenic B
Page 47 and 48:
Origin of and Tectonic Controls for
Page 49 and 50: Metallogenic Belts Formed During Pr
Page 51 and 52: as at Oz, Monster, and Tart, may al
Page 53 and 54: Monashee Metallogenic Belt of Sedim
Page 55 and 56: Clark Range Metallogenic Belt of Se
Page 57 and 58: in addition to the Fe deposits. Min
Page 59 and 60: study) consists of lenses, from 100
Page 61 and 62: Omulev Austrian Alps W Deposit The
Page 63 and 64: ock, including coarse clastic rock,
Page 65 and 66: lative metalliferous brines in a re
Page 67 and 68: Prince of Wales Island Metallogenic
Page 69 and 70: suite of deposits and host rocks ar
Page 71 and 72: margin of the North American Craton
Page 73 and 74: newly created terranes migrated int
Page 75 and 76: (Ryazantzeva and Shurko, 1992). The
Page 77 and 78: tonnes Au and an average grade of a
Page 79 and 80: mafic and felsic metavolcanic rocks
Page 81 and 82: intrusion from about 402 to 366 Ma
Page 83 and 84: Origin of and Tectonic Controls for
Page 85 and 86: mentary rocks of the Cambrian to De
Page 87 and 88: (Preto and Schiarizza, 1985; Schiar
Page 91 and 92: ate and clastic rocks and volcanicl
Page 93 and 94: (Nokleberg and others, 1994c, 1997c
Page 95 and 96: Berezovka River Metallogenic Belt o
Page 99: Finlayson Lake Metallogenic Belt of
Page 103 and 104: Windermere Creek (Western Gypsum) C
Page 105 and 106: (NX, DL, MY), Viliga (VL), and Zolo
Page 107 and 108: South of the main east-west-trendin
Page 109 and 110: ated subduction zone in the Wrangel
Page 111 and 112: icite-biotite-quartz bodies in frac
Page 113 and 114: Canada Cordillera. The granitoid ro
Page 115 and 116: Viliga (VL) passive continental-mar
Page 117 and 118: 32; tables 3, 4) occurs along the n
Page 119 and 120: superterrane, consists mainly of ma
Page 121 and 122: ers, 1994c, 1997c). In southern Bri
Page 123 and 124: mental volcanic rocks of intermedia
Page 125 and 126: a resource of 34.3 million tonnes o
Page 127 and 128: potassic zone. Combined estimated p
Page 129 and 130: and quartz monzodiorite stock and s
Page 131 and 132: and Omolon (OM) cratonal terranes,
Page 133 and 134: in volcanic and volcaniclastic rock
Page 135 and 136: minor calcite, and sporadic pyrite
Page 137 and 138: supergene blanket are interpreted a
Page 139 and 140: deposits and occurrences consist of
Page 141 and 142: onto the Omulevka terrane to form t
Page 143 and 144: superterrane. This belt is interpre
Page 145 and 146: to form along the leading edge of t
Page 147 and 148: quartz, and is virtually not associ
Page 149 and 150: deposits are at Terrassnoe and Kuna
Page 151 and 152:
Peschanka Porphyry Cu-Mo Deposit Th
Page 153 and 154:
The belt is hosted in the Late Jura
Page 155 and 156:
in a island arc that was tectonical
Page 157 and 158:
and Early Cretaceous Koyukuk island
Page 159 and 160:
The deposit consists of disseminate
Page 161 and 162:
The Orange Hill deposit contains an
Page 163 and 164:
49; tables 3, 4) (Foley and others,
Page 165 and 166:
locally Late Triassic marine volcan
Page 167 and 168:
gold in a gangue of quartz, calcite
Page 169 and 170:
Verkhoyansk granite belt, which int
Page 171 and 172:
metallogenic belts are interpreted
Page 173 and 174:
assemblages, which may have been mo
Page 175 and 176:
during hypogene and supergene alter
Page 177 and 178:
collision and regional thrusting, t
Page 179 and 180:
Yur Au Quartz Vein Deposit The smal
Page 181 and 182:
phase has a Rb-Sr isotopic age of 1
Page 183 and 184:
sian Northeast. The belt is hosted
Page 185 and 186:
Host Granitoid Rocks and Associated
Page 187 and 188:
that are up to 600-1,500 m long, av
Page 189 and 190:
Metallogenic Belts Formed During La
Page 191 and 192:
y partly coeval plutons that range
Page 193 and 194:
tion is interpreted as occuring by
Page 195 and 196:
the Badzhal-Ezop and Khingan parts
Page 197 and 198:
and comagmatic with volcanic rocks;
Page 199 and 200:
as interpreted for the Rock Creek d
Page 201 and 202:
source (Yeo, 1992). The Blow River
Page 203 and 204:
2000). The spatial location of the
Page 205 and 206:
to the east in the central Yukon Te
Page 207 and 208:
occur in a 30-km-long belt along ir
Page 209 and 210:
The Emerald deposit has produced ap
Page 211 and 212:
Metallogenic-Tectonic Model for Ear
Page 213 and 214:
cham oceans were closed, and the Ch
Page 215 and 216:
greisenized Mesozoic granite that i
Page 217 and 218:
composition magmatic bodies (with a
Page 219 and 220:
Origin of and Tectonic Controls for
Page 221 and 222:
to Albian pelecypods (Nokleberg and
Page 223 and 224:
quartz-arsenopyrite-pyrrhotite, pol
Page 225 and 226:
thermally altered to siliceous and
Page 227 and 228:
These ore bodies are as much as 1 m
Page 229 and 230:
Eastern Asia-Arctic Metallogenic Be
Page 231 and 232:
Demin, and Krasilnikov, 1974; Nekra
Page 233 and 234:
10 percent Cu, as much as 0.92 perc
Page 235 and 236:
pyrite, pyrite, galena, sphalerite,
Page 237 and 238:
content decreases with depth, as do
Page 239 and 240:
azdelnoye, (2) porphyry Sn deposits
Page 241 and 242:
Karalveem Au Quartz Vein Deposit Th
Page 243 and 244:
Democrat (Mitchell Lode) Granitoid-
Page 245 and 246:
with high-temperature and high-pres
Page 247 and 248:
chalcocite and covellite and also h
Page 249 and 250:
cum-North Pacific, (2) completion o
Page 251 and 252:
(6) In the Paleocene (about 56 to 6
Page 253 and 254:
sists of cinnabar and metacinnabari
Page 255 and 256:
Eastern Asia-Arctic Metallogenic Be
Page 257 and 258:
groups of deposits are interpreted
Page 259 and 260:
Indian Mountain and Purcell Mountai
Page 261 and 262:
and southeastern Alaska (Moll and P
Page 263 and 264:
Nokleberg and others, 1995a; Bundtz
Page 265 and 266:
g/t Au or 368.2 Au gold. The deposi
Page 267 and 268:
wim Group and altered mafic dikes.
Page 269 and 270:
Mount Nansen porphyry Cu-Mo deposit
Page 271 and 272:
A Map 450 500 550 Cross section Dik
Page 273 and 274:
Cretaceous and early Tertiary conti
Page 275 and 276:
deposits, at Chichagoff and Hirst-C
Page 277 and 278:
others, 1994c, 1997c). The signific
Page 279 and 280:
tonnes grading 0.53 percent Ni, 0.3
Page 281 and 282:
with a 0.25 percent cut-off. The de
Page 283 and 284:
Bulkley Metallogenic Belt of Porphy
Page 285 and 286:
Red Rose W-Au-Cu-Ag Polymetallic Ve
Page 287 and 288:
ish Columbia and consists of severa
Page 289 and 290:
during back-arc extension or transt
Page 291 and 292:
stocks and dikes, is associated wit
Page 293 and 294:
etrograde minnesotaite (Fe talc), F
Page 295 and 296:
Specific Events for Early to Middle
Page 297 and 298:
of fractured and faulted Permian-Tr
Page 299 and 300:
sists of a mineralized fracture zon
Page 301 and 302:
dolomite. Wall rock alteration incl
Page 303 and 304:
elt of late Tertiary plutons that a
Page 305 and 306:
plates that exhibit magnetic anomal
Page 307 and 308:
stages (Petrenko, 1999): (1) In the
Page 309 and 310:
mon. The deposit is of medium size
Page 311 and 312:
Metallogenic-Tectonic Model for Lat
Page 313 and 314:
The origin of the Hg deposits of th
Page 315 and 316:
margin or island-arc tectonic envir
Page 317 and 318:
Columbia: Implicatons for the Middl
Page 319 and 320:
Bazard, D.R., Butler, R.F., Gehrels
Page 321 and 322:
Bradley, D.C., Haeussler, P.J., and
Page 323 and 324:
Bundtzen, T.K., Laird, G.M., Caluti
Page 325 and 326:
Cecile, M.P., 1982, The lower Paleo
Page 327 and 328:
Debari, S.M., and Coleman, R.G., 19
Page 329 and 330:
U.S. Bureau of Land Management Open
Page 331 and 332:
Cordilleran Orogen in Canada: Geolo
Page 333 and 334:
Goldfarb, R., Hart, C., Miller, M.,
Page 335 and 336:
Grove, E.W., 1986, Geology and mine
Page 337 and 338:
Høy, T., 1982a, Stratigraphic and
Page 339 and 340:
Jones, D.L., Silberling, N.J., Cone
Page 341 and 342:
Kutyev, F. Sh., Baikov, A.I., Sidor
Page 343 and 344:
Shield—Ultramafic magma and its m
Page 345 and 346:
Manns, F.T., 1981, Stratigraphic as
Page 347 and 348:
Miller, M.L., and Bundtzen, T.K., 1
Page 349 and 350:
Mortimer, N., 1987, The Nicola Grou
Page 351 and 352:
Noble, S.R., Spooner, E.T.C., and H
Page 353 and 354:
Canada Annual Meeting, Saskatoon, S
Page 355 and 356:
Perello, J.A., Fleming, J.A., O’K
Page 357 and 358:
Far East—Mineralogical criteria f
Page 359 and 360:
Roeske, S.M., Mattinson, J.M., and
Page 361 and 362:
Schmidt, J.M., and Zierenberg, R.A.
Page 363 and 364:
formation occurrences: Materialy po
Page 365 and 366:
Struik, L.C., 1986, Imbricated terr
Page 367 and 368:
Valuy, G., and Rostovsky, F., 1988,
Page 369 and 370:
Wolfe, W.J., 1995, Exploration and
Page 371 and 372:
Appendix Table 1. Mineral deposit m
Page 373 and 374:
Table 2 Summary of correlations and
Page 375 and 376:
Table 2—Continued Unit(s) and Cor
Page 377 and 378:
Table 2—Continued Unit(s) and Cor
Page 379 and 380:
Table 3—Continued Metallogenic Be
Page 381 and 382:
Page 383 and 384:
Page 385 and 386:
Page 387 and 388:
Page 389 and 390:
Page 391 and 392:
Page 393 and 394:
Page 395 and 396:
Page 397 and 398:
Page 399 and 400:
Table 4. Significant lode deposits,
Page 401 and 402:
Table 4—Continued Appendix 369 De
Page 403 and 404:
Table 4—Continued Tracy Metalloge
Page 405 and 406:
Table 4—Continued Appendix 373 In
Page 407 and 408:
Table 4—Continued Deposit Name Mi
Page 409 and 410:
Table 4—Continued Mainits Metallo
Page 411 and 412:
Page 413 and 414:
Page 415 and 416:
Table 4—Continued Whitehorse Meta
Page 417 and 418:
Page 419 and 420:
Page 421 and 422:
Table 4—Continued Appendix 389 LA
Page 423 and 424:
Page 425 and 426:
Table 4—Continued Surprise Lake M
Page 427 and 428:
Table 4—Continued Sredinny Metall
Page 429:
show all

USGS Professional Paper 1697 - Alaska Resources Library

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?