USGS Professional Paper 1697 - Alaska Resources Library

onto the Omulevka terrane to form the Munilkan (MU)
ophiolite terrane, and the Uyandina, Kybytygas, and Indigirka
ophiolite terranes of Oxman and others (1995).
(5) The Angayucham Ocean (Kobuck Sea of Plafker and
Berg, 1994), along with the South Anyui Ocean, continued to
receive sparse continental-derived detritus. Previously rifted
terranes, including the Kilbuck-Idono cratonal (KI) and the
combined Nixon Fork-Dillinger-Mystic passive continentalmargin
(NX, DL, MY) terranes, were near the North American
Craton Margin.
(6) The dextral-slip imbrication of the Stikinia-Quesnellia
arc and associated subduction-zone terranes was completed
along the Tally Ho shear zone (Hansen and others, 1990; Hart,
1995). Alternatively, the oroclinal warping of the Stikinia-
Quesnellia island-arc and associated subduction-zone terranes
was completed (not depicted in fig. 47; Mihalynuk and others,
1994). For either interpretation, migration of the Stikinia-
Quesnellia arc and associated terranes toward North America
was accomplished by subduction and (or) obduction of the
Seventymile oceanic plate along the continental margin.
(8) The subduction-related volcanic and plutonic arc
rocks of the Quesnellia part of the arc, consisting of the
Takla Group and the coeval igneous belts formed in response
to continued subduction of part of the Cache Creek oceanic
plate (CC; Mihalynuk and others, 1994). The Stikinia part
of the arc consisted of the extensive suite of the subduction-related
volcanic and plutonic arc rocks of the Hazelton
Group that also formed in response to subduction of part of
the Cache Creek oceanic plate. Remnants of this oceanic
plate may be preserved in the terrane of ultramafic and
related rocks that occurs discontinuously along the Denali
strike-slip fault (DE, fig. 47) for several hundred kilometers
(Nokleberg and others, 1994b).
(9) Forming in the Stikinia-Quesnellia arc and continuing
on from the Early Jurassic were the Coast Mountains (CM),
Copper Mountain (North; CMN), Copper Mountain (South;
CMS), Galore (GL), Guichon (GU), Klotassin (KL), Texas
Creek (TC), and Toodoggone (TO) belts that contain either
granitic magmatism-related deposits or deposits related to
felsic to mafic marine volcanism.
(10) Also completed was obduction of parts of the Seventymile
and Slide Mountain oceanic plates onto the North
American Craton Margin (NAM; Mihalynuk and others,
1994). Migration of the Stikinia-Quesnellia arc and associated
terranes toward the North American Craton Margin was
accomplished by subduction of the Seventymile oceanic plate
along the continental-margin and by obduction.
(11) Outboard and perhaps at a lower paleolatitude (either
25° or 45°), the Talkeetna and Bonanza arcs continued activity
in the Wrangellia superterrane (WRA). This extensive arc
formed along most of the length of the Wrangellia superterrane
with coeval equivalents in the Cadwallader (CD) island arc
and Methow (MT) turbidite-basin terranes. Forming in the arc
and continuing on from the Early Jurassic were the Talkeetna
Mountains-Alaska Range metallogenic belt, which contains
kuroko massive sulfide deposits, the Alaska Peninsula (AP)
Late Jurassic Metallogenic Belts (163 to 144 Ma; figs. 48, 49) 109
metallogenic belt, which contains Cu- and Fe-skarn deposits,
and the Island Porphyry (IP) metallogenic belt, which contains
granitic-magmatism-related deposits. Associated with the Talkeetna
and Bonanza arcs was subduction of part of the Cache
Creek oceanic plate to form the Chugach (CG), Bridge River
(BR), and possibly Baker (BA) terranes.
Late Jurassic Metallogenic Belts (163
to 144 Ma; figs. 48, 49)
Overview
The major Late Jurassic metallogenic belts in the Russian
Far East, Alaska, and the Canadian Cordillera are summarized
in table 3 and portrayed on figures 48 and 49. The major
belts are as follows: (1) In the Russian Southeast, the Ariadny
(AR) belt, which contains zoned mafic-ultramafic Ti deposits,
is hosted in zoned mafic-ultramafic plutons intruding the
Samarka subduction-zone terrane. The belt is interpreted as
forming along a transform continental margin. (2) Also in the
Russian Southeast is the North Bureya (NB) belt of graniticmagmatism-related
deposits, which is interpreted as forming
in the Umlekan continental-margin arc. (3) In the central
part of the Russian Far East is the Stanovoy (ST) belt, which
contains anatectic, granitic-magmatism-related deposits and is
interpreted as forming during accretion of the Bureya superterrane
to North Asian Craton. (4) In the Russian northeast is
the Chersky-Argatass Ranges (CAR) belt of kuroko massive
sulfide deposits and the Yasachnaya River (YS) belt of
granitic-magmatism-related deposits. Both metallogenic belts
are hosted in the Indigirka-Oloy volcanic-plutonic assemblage
and are interpreted as forming in the Uyandina island arc. (5)
In the Russian northeast, the Oloy (OL) belt contains graniticmagmatism-related
deposits and is hosted in the Oloy island
arc. (6) In the same region, the Pekulney (PK) belt, which contains
basaltic Cu deposits, is hosted in Late Jurassic oceanic
crustal rocks that were subsequently tectonically incorporated
into the Pekul’ney subduction-zone terrane. (7) In the same
region, the Tamvatney-Mainits (TAM) belt, which contains
podiform Cr deposits, is hosted in zoned mafic-ultramafic
plutons, and the Mainits (MA) belt, which contains kuroko
massive sulfide deposits, are both interpreted as forming in
the Mainitskiy island arc. (8) Also in the same region, the
Svyatoy-Nos (SVN) belt, which contains Au-Ag epithermal
vein deposits, is hosted in the Svyatoy-Nos volcanic belt,
which is interpreted as forming in the conamed island arc. (9)
In the Russian Northeast, Alaska, and the northern Canadian
Cordillera, the Eastern Seward Peninsula and Marshall (ESM),
Kobuk (KB), Kuyul (KUY), southwestern Alaska (SWA),
and Yukon-River (YR) belts, which contain podiform Cr and
related deposits and also zoned mafic-ultramafic PGE deposits,
are hosted in mafic-ultramafic plutons that intruded into
the basal parts of various island arcs. These arcs include the