|Title||Gold mineralization footprint in glacial sediments: geochemistry and indicator minerals from the Amaruq deposit (Nunavut, Canada)|
|Author||de Bronac de Vazelhes, V; Boulianne-Verschelden, N; Beaudoin, G; McMartin, I; Côté-Mantha, O; Simard, M|
|Source||RFG 2018 - Resources for Future Generations; by RFG2018 Steering Committee; 2018 p. 1|
|Alt Series||Natural Resources Canada, Contribution Series 20170378|
|Meeting||Resources for Future Generations 2018; Vancouver; CA; June 16-21, 2018|
|Subjects||economic geology; surficial geology/geomorphology; mineralogy; geochemistry; Science and Technology; Nature and Environment; mineral deposits; gold; Amaruq Deposit|
|Program||GEM2: Geo-mapping for Energy and Minerals Rae Province, Synthesis of glacial history|
|Released||2018 06 16|
Understanding the nature of glacial dispersal processes affecting a mineral deposit is challenging. It requires reconstruction of the glacial history, and knowledge about the
geochemical and mineralogical signature of the mineralization. The Amaruq gold property, owned by Agnico Eagle mines Limited, is located 50 km NNW of the Meadowbank mine. The gold mineralization, perpendicular to the main ice flow, makes it a good
study area for glacial dispersal.
Principal component analysis of surface sample geochemistry (<63 µm fraction, Aqua regia digestion, ICP-AES & -MS), covering the Amaruq area with a 100 m sample spacing, was performed to assess geochemical
associations and study dispersal patterns. The first component (41% of the variance) shows an association of gold with silver, arsenic, cobalt, chrome, nickel, copper, antimony and tungsten. This component
likely captures the variance related to
gold mineralization hosted by ultramafic rocks. Kriging of the first component scores shows three NNW anomalies down-ice of known mineralized occurrences that are interpreted as glacial dispersal trends along the main ice flow direction. In an area
of thick till, the deposit anomaly reaches the till surface approximately 1.5 km down-ice whereas, in an area covered with a more proximal till,anomalies reach the surface less than 500 m down-ice.
A total of 61 samples were also collected from
frostboils along four NNW transects centered on till anomalies and covering various till types for geochemical and indicator minerals investigations. Gold and scheelite grains counts on the Whale Tail transect increase approximately 1.4 km down-ice
from the outcropping zone. Western transects show more variability, with an increase down-ice of mineralized basement, and a decrease to background counts after 2 km. Indicator mineral grain counts and geochemical anomalies display similar patterns,
and highlight the need to characterized till types of the area of interest in order to better constraint glacial dispersal.
|Summary||(Plain Language Summary, not published)|
This poster presents the results of a detailed till geochemical survey completed in 2015 on the Amaruq gold exploration project in central mainland
Nunavut. The interpretation of this survey as well as targeted till and mineralized bedrock sampling for indicator minerals and surficial geology mapping in 2016 and 2017 form part of two MSc thesis research projects to develop till geochemistry and
indicator mineral methods for gold exploration in areas underlain by permafrost. The Geological Survey of Canada is involved in co-supervising the students within the Chaire de recherche industrielle CRSNG¿Agnico Eagle en exploration minérale at
Laval University. The study area is part of the GEM-2 Glacial Synthesis Rae Project and the work will contribute to improve mineral exploration methods in glaciated terrain in the Rae Province.