USGS Professional Paper 1697 - Alaska Resources Library

70 Metallogenesis and Tectonics of the Russian Far East, Alaska, and the Canadian Cordillera
Ingenika Metallogenic Belt of Southeast Missouri
Zn-Pb-Ag-Ba Deposits, and Manto Zn-Pb-
Ag Deposits (Belt IN) Northern British Columbia
The Ingenika metallogenic belt of Southeast Missouri
Zn-Pb-Ag-Ba deposits and manto Zn-Pb-Ag deposits occurs
in central British Columbia. The belt is hosted in Late Proterozoic
to Devonian carbonate-dominated strata of the proximal
pericratonic Cassiar terrane (fig. 17; tables 2, 3) (Nokleberg
and others, 1997b, 1998). The significant deposits are in the
Wasi Lake area at Susie, Beveley, and Regent.
Westlake Area (Susie, Beveley, Regent) Southeast
Missouri Zn-Pb-Ag-Ba Deposits
The Susie, Beveley, and Regent Southeast Missouri Zn-
Pb-Ag-Ba deposits consist of sphalerite, galena and barite in
four zones of vein and breccia filling that are hosted in Late
Proterozoic to Devonian platformal dolostones (EMR Canada,
1989; Ferri and others, 1992). The deposits contain estimated
resources of 2.82 million tonnes grading 2.24 percent Zn, 1.42
percent Pb, and 36.3 g/t Ag. The deposit age is interpreted as
Cambrian to Devonian, similar to the host rocks. A series of
probably early Tertiary foliated felsic dikes occur along the top
of Bevely Mountain. The dikes are as much as 200 m wide.
Origin of and Tectonic Setting for Ingenika Metallogenic Belt
The Southeast Missouri Zn-Pb-Ag-Ba deposits and
Manto Zn-Pb-Ag deposits in the Ingenika metallogenic belt
possess an ore mineral assemblage and morphology characteristic
of manto replacement (Nelson, 1991). The deposits
in the belt are interpreted as forming during deposition of
metal from low temperature brines that may have originated
within an adjacent shale basin. The Ingenika metallogenic
belt is herein interpreted as a displaced part of the Cathedral
metallogenic belt of Southeast Missouri Zn-Pb-Ag deposits
(Dawson, 1996a; Nokleberg and others, 1997b, 1998), which
occurs mainly in the western margin of the North American
Craton Margin. Rock sequences in the Cassiar terrane are
similar to those in the western North American Craton Margin
to the south, thereby suggesting a dextral, northward displacement
of Cassiar terrane about 700 km along the Tintina-Rocky
Mountain Trench Fault System in the Late Cretaceous and
early Tertiary, as proposed by Gabrielse (1985). Restoration of
this displacement would juxtapose the Ingenika and Cathedral
metallogenic belts of Southeast Missouri Pb-Zn deposits.
Cathedral Metallogenic Belt of Southeast
Missouri Zn-Pb-Ag Deposits Southern British
Columbia (Belt CA)
The Cathedral metallogenic belt of Southeast Missouri Zn-Pb-
Ag deposits occurs in southern British Columbia (fig. 17; tables 2,
3) (Nokleberg and others, 1997b, 1998). The metallogenic belt is
hosted in the Middle Cambrian Cathedral and Jubilee Formations,
which contain dominantly carbonate rocks that are part of a shallowwater,
carbonate-clastic shelf deposited along the passive continental
margin of the North American Craton Margin. The deposits in the
Cathedral metallogenic belt contain the only Southeast Missouri Pb-
Zn deposits in the Canadian Cordillera with significant production.
The significant deposit is at Monarch (Kicking Horse).
Monarch (Kicking Horse) Southeast Missouri Zn- Pb Deposit
The Monarch Southeast Missouri Zn-Pb-Ag deposit
extends along strike for more than 1,370 m in folded, brecciated,
and dolomitized limestone of the Cathedral Formation
(Høy, 1982; MINFILE, 2002). The deposit consists of argentiferous
galena, sphalerite, and pyrite that occur as fillings in
north-south striking, vertical fissures along the east limb of
an anticline. Combined production and reserves are 820,000
tonnes grading 5.63 percent Pb, 8.85 percent Zn, 31 g/t Ag.
The deposit age is interpreted as Middle Cambrian. Minor
similar occurrences are at Hawk Creek, Steamboat and Shag,
to the southeast of the Monarch (Kicking Horse) deposit.
Origin of and Tectonic Controls for Cathedral
Metallogenic Belt
The age of mineralization for the Cathedral metallogenic belt
is not known precisely, and the genesis of Southeast Missouri-type
deposits is debatable. Faults, breccias, and other open spaces in the
host shelf limestone are filled by an assemblage of sulfide minerals
and calcite-dolomite-fluorite gangue. The ore metals probably
were transported and deposited by low-temperature brines that
may have originated within the adjacent shale basin. The Cathedral
metallogenic belt is correlated with the DevonianI(?) Ingenika
metallogenic belt in central British Columbia, described above.
This relation suggests dextral, northward displacement of about
700 km along the Tintina Fault system (Gabrielse (1985).
Southern Rocky Mountains Metallogenic Belt of
Stratabound Barite-Magnesite-Gypsum Deposits
(Belt SRM) Southern British Columbia
The Southern Rocky Mountains metallogenic belt of stratabound
barite-magnesite-gypsum deposits (fig. 17; tables 3, 4)
occurs in southeastern British Columbia and is hosted in passive
continental margin sedimentary rocks of the North American
Craton Margin. The significant deposits are at Brisco, Forgetmenot
Pass, Kootenay River Gypsum, Lussier River (United
Gypsum), Marysville, Mount Brussilof, Parson, and Windermere
Creek (Western Gypsum) (table 4) (Nokleberg and
others 1997a,b, 1998). Most of the deposits range in age from
Cambrian to Devonian; a few formed in the Triassic (Nokleberg
and others, 1997a,b). Most of the magnesite and barite
deposits in the belt are hosted primarily in Cambrian carbonate
units. In southeastern British Columbia, the belt contains
a major group of gypsum mines that are hosted in Devonian
strata. Also occurring in the belt are local magnesite, and Zn-
Pb deposits, as at Kicking Horse.