British Columbia Ministry of Energy, Mines and Natural Gas and Responsible for Housing
News | The Premier Online | Ministries & Organizations | Job Opportunities | Main Index

MINFILE Home page  ARIS Home page  MINFILE Search page  Property File Search
Help Help
File Created: 24-Jul-1985 by BC Geological Survey (BCGS)
Last Edit:  27-May-2021 by George Owsiacki (GO)

Summary Help Help

NMI 094C6 Pb1
Name KNOLL, BURN, SWAN, RAIN Mining Division Omineca
BCGS Map 094C043
Status Showing NTS Map 094C05E
Latitude 056º 28' 30'' UTM 10 (NAD 83)
Longitude 125º 30' 59'' Northing 6261786
Easting 345008
Commodities Lead, Zinc, Silver Deposit Types E12 : Mississippi Valley-type Pb-Zn
Tectonic Belt Omineca Terrane Cassiar
Capsule Geology

The Knoll lead-zinc occurrence is located 15 kilometres east-northeast of Aiken Lake, approximately 97 kilometres northeast of the community of Germansen Landing.

Sphalerite, galena and barite occur in brecciated, silicified dolostone of the Ordovician to Lower Devonian Echo Lake Group (D. DuPre, personal communication, October 1992). The mineralization occurs near the top of a knoll, near its northwest corner, within a rusty weathering area measuring 200 by 200 metres. A float sample of mineralized dolomite found downslope from the gossanous area assayed 3.64 per cent lead, 0.1 per cent zinc, 19.88 grams per tonne silver and 1.4 per cent barium (Assessment Report 4605, page 7).

The Knoll consists of a very prominent 300-metre-high hill elongate in a northwest direction. The northeast side is very steep while the southwest side is of somewhat gentler slope that is close to a dip slope. The upper portion of the hill is dominated by a dolomite that is 60 to 100 per cent silicified into a blue-grey, chert-like rock. Remnant patches and areas of dolomite confirm the original carbonate character of the rock and also show fenestral and cryptalgal laminae characteristic of the Echo Lake Group. The silicified lithologies overlie lighter limestones and dolomites that are thought to probably be Mount Kison Formation (Lower Cambrian Atan Group) though no archaeocyathids were identified. In the stream valley on the northwest side of the Knoll, quartzites were mapped that may be Mount Brown Formation (Lower Cambrian Atan Group) (Assessment Report 23321).

Several showings occur on the northwest face of the Knoll. The most prominent consists of a 10 by 15 metre area of Mount Kison Formation carbonates cut by a number of irregular barite plus galena with minor sphalerite and smithsonite veins up to 0.5 metre wide. Some of the veins are located along a fault along which the rock is brecciated and dolomitized. The veins comprise 50-95 per cent white barite, 1-4 per cent fine- to medium-grained galena and 1-2 per cent orange-brown sphalerite. A semi-continuous chip sample (WR 93-046) over 3.5 metres of the best mineralized interval assayed 2.2 per cent lead 3.0 per cent zinc and 39.9 grams per tonne silver. Lower on the slope an outcrop of ankeritic and calcspar-rich Mount Kison Formation limestone reported to host 1-2 per cent disseminated sphalerite analyzed from a grab sample (WR 93-044) of the best 40 centimetres of mineralization 1.3 per cent lead and 17.2 per cent zinc (Assessment Report 23321). On the southeast face of the Knoll, float of dolomitized Mount Kison Formation limestone hosts disseminated sphalerite, galena and variable barite.

The area was prospected in the 1960s by Cominco Ltd. (A.B. Mawer) whose work discovered most of the known showings. Some of the showings were subsequently trenched by Mawer. During 1972, SEREM Ltd. carried out a regional lead/zinc stream sediment geochemical program throughout the Omineca Mountains. This led to the staking of three small properties (Swan (094C 073), Burn/Knoll (094C 082/094C 141) and Rain (094C 074)). In 1973, SEREM conducted programs of line cutting, soil geochemistry, geological mapping, trenching and ground geophysical (horizontal shootback electromagnetic) surveys on each property and in 1974 drilled 13 holes (656.8 metres) on the Rain property; no assessment was filed and the properties were allowed to lapse. The present Swan property (ca. 1993) covers most of the three old properties. In 1992, the area was mapped at 1:50,000-scale by F. Ferri and crew of the British Columbia Geological Survey; limited silt sediment sampling and analysis was undertaken as part of this program. In 1993, work by Cominco Ltd. included a detailed soil geochemical and mapping grid on the Swan, and contour soil geochemistry and reconnaissance geology on the Rain, Knoll, and Gilliland Tuff (Upper Devonian-Permian Big Creek Group) areas. A regional silt sampling program was also undertaken on the property.

Bibliography
EMPR ASS RPT *4605, 4608, 21434, 22811, *23321
EMPR FIELDWORK 1991, pp. 127-145; 1992, pp. 109-134; 2018, pp. 31-53; 2019, pp. 25-47
EMPR P 1992-01, pp. 127-145; 1993-01, pp. 109-134; 2019-01, pp. 31-53; 2020-01, pp. 25-47
EMPR OF 1992-11; 1993-2
EMPR GEM 1972-477; 1973-398
GBC 2021-01, pp. 105-120
GSC MAP 1030A
GSC MEM 274

COPYRIGHT | DISCLAIMER | PRIVACY | ACCESSIBILITY