USGS Professional Paper 1697 - Alaska Resources Library

Eastern Asia-Arctic Metallogenic Belt:
Chukotka Zone of Igneous-Related Hg
Deposits (Belt EACH), Northeastern Part of
Russian Northeast
The Chukotka zone of igneous-related Hg deposits (fig.
102; tables 3, 4) occurs in the northeastern part of the Russian
Northeast. The Chukotka zone contains numerous Hg deposits
and occurrences, trends roughly east-west, is about 1,000
km long and ranges from 100 to 150 km wide. The significant
deposits in the belt are (table 4) (Nokleberg and others
1997a,b, 1998) clastic sediment-hosted Hg deposits at Kyttamlai
and Palyan, volcanic-hosted Hg deposits at Kulpolney,
Omrelkai, and Plamennoe, and a silica-carbonate Hg deposit
at Matachingai. The deposits occur both in the Okhotsk-Chukotka
volcanic-plutonic belt and in the igneous rocks that
intrude the Jurassic and Early Cretaceous sedimentary rocks
A
A
Map
Cross section
Late Cretaceous and Early Tertiary Metallogenic Belts (84 to 52 Ma) (figs. 102, 103) 223
of the Raucha Basin (Nokleberg and others, 1994c, 1997c).
The Chukotka zone partly overlies the Anyui-Beringovsky and
Chaun metallogenic zones (fig. 102).
The Hg deposits in the Chukotka zone generally occur in
linear belts as much as several kilometers long and are partly
controlled by northwest-southeast-trending faults. The deposits
are hosted in rhyolite, andesite, and more rarely ultramafic
rocks and show a distinctive relation basalt and lamphrophyre
dikes (Obolensky and Obolenskaya, 1971). The Hg deposits
occur in faulted areas in volcanic domes, horsts, subsiding
calderas, and anticlines. The deposits generally occur in stockworks
and veins, and cinnabar is the predominant mineral,
generally in association with ankerite, quartz, and dickite. The
major Hg districts are at Tsentral Chukotsky, Sredne-Anadyrsky,
and Vostochno-Chukotsky (Babkin, 1975; Kopytin, 1978).
The Palyavaam area (Tsentral Chukotsky district) is the best
studied and contains the Palyanskoe and Plamennoe deposits.
Some deposits are economic.
B
B
C
C
Unconsolidated
deposits
(Quaternary)
Granite porphyry
(Late Cretaceous)
Felsic volcanic rocks
(Late Cretaceous)
Lamprophyre
(Late Cretaceous)
Sandstone (Triassic)
Siltstone (Triassic)
Ore body
Strike and dip of
bedding
Fault
Contact
0 300 m
500 m
Figure 106. Maiskoe disseminated Au-sulfide deposit, Anuyi-Beringovsky zone, eastern Asia-Arctic metallogenic belt,
Russian Northeast. Schematic geologic map and cross section. Adapted from Sidorov and Eremin (1995). See figure 102
and table 4 for location.
0