Title | The relationship between mercury occurrence and mining activity in the Nottaway and Rupert river basins of north-western Quebec |
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Licence | Please note the adoption of the Open Government Licence - Canada
supersedes any previous licences. |
Author | Maclatchy, J E; Jonasson, I R |
Source | Geological Survey of Canada, Paper 74-56, 1974, 10 pages, https://doi.org/10.4095/102562 Open Access |
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Year | 1974 |
Document | serial |
Lang. | English |
Media | paper; on-line; digital |
File format | pdf |
Province | Quebec |
NTS | 32 |
Lat/Long WENS | -80.0000 -72.0000 52.0000 48.0000 |
Subjects | geochemistry; industrial minerals; environmental geology; analyses; analytical methods; atomic absorption analyses; concentrates; mercury; mercury geochemistry; mining properties; sulphides;
tailings |
Released | 1974 11 01; 2016 03 15 |
Abstract | Composite samples of ore heads, concentrates and tailings were collected from some base metal (Cu, Zn, Pb) mines in northwestern Quebec. Daily, weekly and monthly composites were analyzed for mercury.
It was shown that monthly composites provided the most representative and reproducible values for mercury in a given ore deposit. Fluctuations due to local variations in ore grade tend to be smoothed out in the longer term composites. The mines in
question are near Chibougamau, Chapais, Matagami, Val d 'Or and Noranda and lie within the drainage basins of the Bell and Rupert river systems. The mines near Chibougamau produce only copper, those near Matagami yield considerably more zinc. whilst
those near Noranda-Val d'Or produce copper, zinc and lead in major quantities. Mercury contents of these base metal ores were observed to increase with increasing zinc content of the ore, indicating that most of the mercury is present as a
constituent of sphalerite ( ZnS). Mercury contents of zinc concentrates ranged from 2 ppm (Matagami area) through 20 ppm (Noranda area) up to 150 ppm (Val d'Or area). Mercury in copper concentrates was found to be much less abundant, usually 1 to 10
per cent of that found for a zinc concentrate from any given mine. In all areas, relatively little mercury was found to carry through into tailings which consist of waste silicates and iron sulphides. In the mines of primary interest, namely those
near Chibougamau and Matagami, less than 0. 20 ppm mercury was found in most tailings composites. Values reached about 1 ppm in the Val d'Or area mines tailings and slightly higher in waste materials from the adjacent Noranda area. In general,
tailings were observed to be well confined in ponds and the little mercury that is potentially available is considered unlikely to influence mercury levels reported for the local drainage systems. Other possible sources of mercury, such as
Precambrian shales (slates) which are widespread throughout the Bell-Nottaway and Rupert River basins, are proposed and discussed. Data for ores and tailings from other regions of Canada are presented for comparative purposes. |
GEOSCAN ID | 102562 |
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