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

I (2) The East Sikhote-Alin (es) continental-margin arc was initiated. This major Andean-type arc overlapped p&ly
accreted adjacent terranes in both the Russian Southeast and to the south. This arc extended for a distance of over 1,600 ha along
4he active Russian Southeast continental margin. Forming as part of the arc was the West Sakhalin (WSA) turbidite bash ttrrane.
Forming in the East-Sikhote arc were the Kema, Lower Amur, Luzhklnsky, Segeevka, and Taukha meiallogenic belts. Also I
associated with the East-Sikhote arc was oblique subduction of part of the Ancestral Pacific Ocean plate (PAC) to form the Hidaka
'- (HI), hivs (ANY), and Nabilsiy (NAB) temes. lrorporated into ibe Aniva and Nabilsky terranes were he. mcanogenic re
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Figure 81. Early Late Cretaceous (Cenomanian through Santonian 100 to 84 Ma) stage of metalogenic-tectonic model. Refer to
text for explanation of metallogenic-tectonic events, to tables 3 and 4 for descriptions metallogenic belts and significant deposits, C'
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and to figure 18 for explanatbn of abbreviatbns, symbols, and patterns. Adapted from Nokleberg and others (1997b, 1998. 2000). , :! 7 -
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Mn and Cyprus massive sulfide depaaits oflbe Aniva-Nabil (ANN) mctallogeaic W lba4 formed in Late dkceous oceanic crust *k$ A:
.-,-- and ... . jslm arc rocks.
(3) The Khingan continental margin arc (ko) codinucd activity. Continuing in the arc w# ibu Badzbl-Ezup-~
CBZ-ll) belt of mitic-magmatism-related deposits. 4- I
(4) Subduction stepped seaward, afier the accretion of Ihe Mainitskiy arc with the comaprsnt PrcspEion ofthe OkhalslC-!*
Chukotka continental-margin arc (oc) and related Pen% (forearc) sedimentary basin @n) along.& mw contimt?l mu*. ,
This major Andean-type arc overlapped the previously acxreted Kolym-Omolon superterrant, part of the North AgiaP Getan
Margin (NSV), and adjacent terranes in Russian Northeast and Westcm Alaska, aml extended for about 3,500 lun along an &e
continental margin. Associated with the arc was oblique subduction of part of the ancestral Pacific Ocean plate to form the West
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Kamchatka (WK), Ekonay (EK), and Yanrmay (YN) terranes. Forming hr tbe Okhotsk-Chukolka arc was the Eastem Asia
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metallogenic belt of grmitic-mapatism-relaid deposits which contained a complex array of zones. The zones were the Chaun
, 44) (CN), Dogdo-Wot @E), Korkodon-Nayakhan (KN), Koni-Yablon (KY), Okhotsk (OH). Ornsrdrchan (OM), and Verkhna 3 F ,;
ap - . Kolyma (VK) zones. Each zone contains a characleristic suite of mined deposit types which are herein interpreted as reflectink
the geochemical signam of the underlying terra- through which the granitic magmas ascended. Also forming in the Okhots4
Cbukotlia volcanic-plutonic belt, and pnipherally related to the Eastern Asia rne-tallo(leric belt, wen Le Adycha-Taryn (AT), , , !
Cbokurdak (CD), and Vostochno-Verkhoyaask (W) meteltogenic belts.
(5) In the Arctic Ocean, sea-floor spreading and associated rifling continued (tawver and &alese, 1999 &mu and
others, 1990, 1991, 1998) with the formation of new oceanic crust and the combined Alpha and Mdeleev Ridges (am) w kbm ? 1
interpreted as large piles of hot-spot basalt and associated deposits (Granlz and oks, 1990. 1991, 1998). Tk large Amtre 'r -
(ab), Canada (cb) and Eurasia (eb) Besbs continued to form. During the opening of Pe basin, No& knericlo cootinmtai margiv$d
terranes, including the Arctic Alaska superkrranc (AA) and the Chukotka tenane (CH). a d
oulbaard oceanic d idand terranes , . Y
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