Stream Sediment Geochemistry in the Mackenzie Mountains

Stream Sediment Geochemistry in the Mackenzie Mountains

geologist walking in stream with white precipitate

Description

Looking at stream sediments provides an effective way to find mineral deposits in remote areas where there is an established drainage network. Weathering of rocks breaks off small bits as silt and sand grains that are washed down stream. Analyzing the chemistry of the sediments in the rivers and valleys gives a snapshot of the rocks upstream allowing large areas to be identified as prospective or not perspective for mineral deposits. The attention of exploration efforts can be focused on the most prospective regions in a very cost effective fashion. Many large mineral deposits that have gone on to become mines were discovered using stream sediments.

Mountain

Location

The study area is approximately 600 x 450 km and located between the Mackenzie River and the Yukon Border in the Mackenzie Mountains. Sampling stream sediment geochemistry works best in areas with rivers and streams in stable long-established courses and in regions with hills and mountains

Gold grains with scale bar

Justification

The Mackenzie Mountains have excellent potential for new mineral deposits.  The region has not seen a lot of prospecting or exploration and yet known deposits such as Mactung, Cantung, Howards Pass are amongst the world’s largest. The surface exposure of mineral deposits can be quite small, but the sampling of streams quickly shows areas where exploration efforts can be focused. The sampling program also collects water samples and the chemical analyses on the sediments and water provide a good indication on the natural variability of metal contents in rivers within the region. 

Geologist sampling stream sediment

Approach

The protocols utilized for the survey were developed by the Geological Survey of Canada for the National Geochemical Reconnaissance (NGR) program. By utilizing a standard set of sample collection and analytical techniques, the samples and their results can be included in a national database of geochemical surveys. The national database has been constructed to supply data for resource assessments, mineral exploration, geological mapping, and environmental studies. The sample collection, preparation procedures, and analytical methods are strictly specified and monitored to ensure a high level of quality assurance and quality control, which ensures consistent and reliable results regardless of the area, date of the survey, or the analytical laboratory utilized (Friske and Hornbrook, 1991).

Braided stream in the Mackenzie Mountains

Schedule

The first NTGO geochemistry survey was published in 2003. Since then nearly the entire area of the Mackenzie Mountains has been covered through a sequence of surveys conducted on an annual basis. All of these survey results have been published to date. Additional surveys will be conducted when the resources are available.

Measuring water quality

Partners and Support

Project Partners:
Geological Survey of Canada
Protected Areas Strategy
Selwyn Resources
North American Tungsten
Canadian Zinc

Scientific Collaborators:
Stephen Day, Geological Survey of Canada
Heather Jamieson, Queens University
Toon Pronk, Government of New Brunswick
Stu Averill, Overburden Drilling Management

Keywords

Mackenzie Mountains, Surficial Geochemistry, Water Chemistry, Mineral Potential, Mineral Deposits, Stream pH, Stream Conductivity