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

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a a - --rich sandstone
~b-Qmg@nerals~
in sndsme
Sedimentmy and
mmmrptaic rodc
m Gabtwo and dbm (La& Prcdemok}
/ Fault
Figure 6. Verkhny-Omolon ironstone hktpogit, Omdon metallogenic bit, Russian Ndmist. Schematic gdogl~: map. Mapipxi ern
Gelman and Fadeev (1983).
correlative with the Omolon terrane of the Kolyma-Omolon superternme, or the Okhotak terrfum, both in tbe Russian Northeast
and interpreted as rifted fragments of the North Asian Craton (fig. 2) (Nokleberg and others, 1994~~ lWc, 2000). Tbe Omobn
terrane has a somewhat similar stratigraphy and also contains irorlgtone deposits in the Omolon msrall@c belt.
Metallogenic Belts Formed During Proterozoic
Sedimentation, Rifting, and Hyclrothemal Activity
Along Cratons or Craton Margins
Sinuk River Metallogenic Belt of
Massive Sulfide-Barite and
Stratabound Fe and Mn Deposits (Belt SR)
Northwestern Alaska
The Sinuk River metallogenic belt of stratiform massive sulfide-barite and stratabound Fe deposits occurs in the Sin&
River area in the southwestem part of the Seward Peniyula in northwestern Alaska (fig. 3; tables 3.4) (Nokleberg md ohm,
1997b, 1998). Tbe metallopnic belt occurs in a 250 krn region of metamorphosed, upper Paleozoic, carbonate-dominated rocks
of the Seward metamorphosd continental margm terrane (Nokleberg and others, 1994~. 1997c), about 30 km west ofNome
(Herreid, 1968; Hudson and others, 1977; Bundtzen and others, 1994, 1995; Newberry and others, 1997). At least 15 separate
occurrences of massive to disseminated galena, sphalcrite, fluorite, and barite, and massive hematite occur in the area. The
deposits vary widely in morphology and size and consist of: (1) disseminated to massive basite sulfide lex~s~ (Aurom Creek,
Nelson, Rocky Mountain Creek, Quany) which are hosted in felsic metavolcanic schist, carbonate rock, and memorphmed
mafic flows(?), and which are interpreted as kuroko massive sulfide and replacement dep~dts; and (2) massive, stratabound