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Geochemical Analysis Results of Rock Samples of Economic Interest

The table of lithogeochemical analyses of samples of economic interest presents the analytical results of mineralized rock samples collected during the Ministère‘s yearly geological mapping campaigns across Quebec for elements of economic interest. Mineralized sites with values exceeding “showing” thresholds (table below) are subject to a “Mineralization record” in the metallic deposit module of the Quebec Geomining Information System (SIGÉOM). “Anomalous” and “significant” thresholds (table below) highlight samples below showing threshold, but sufficiently high to be of interest for mineral exploration.

The sequential number in the first column links to the corresponding analysis in the SIGÉOM database. A hyperlink is also provided to the interactive map to locate the analytical result in question.

The “complete” display, under “Display Format” in the left-hand panel, lists all the analyses and elements available in the area of interest.

 

SHOWING, ANOMALOUS AND SIGNIFICANT THRESHOLDS FOR GEOCHEMICAL ANALYSES

Showing Thresholds
An analysis yielding a value above or equal to showing threshold for a given element. A mineralization record is created in the SIGÉOM database (metallic deposit section in SIGÉOM à la carte).

 

Anomalous and Significant Thresholds
Anomalous and significant thresholds were determined using statistical processing on a SIGÉOM database of 338 089 analyses dated June 2017. No distinction was made as to the source of the data or the analytical method.
Elements analyzed are: Ag, Au, Be, Co, Cr, Cu, EGP, Fe, Li, Mn, Mo, Nb, Ni, Pb, Pd, Pt, REE, Rh, Sb, Sc, Sn, Ta, Th, Ti, U, V, W, Zn and Zr.

 

Anomalous Thresholds
These thresholds allow extracting the “near showing” analyses. Example: 0.4 g/t of gold in a sample may be of interest to exploration companies. The 95th percentile was calculated for each element. 95% of contents are below this value and 5% above. Results were retained and found to be statistically reliable for Ag, Au, Cr, Cu, Fe, PGE and REE. For other elements, adjustments were required to obtain cut-off values expressed as percent of the showing thresholds:
     – 30% of showing treshold: Be, Co, Li, Mn, Mo, Nb, Pb, Pd, Pt, Sb, Sn, Ta, Y, Zn and Zr;
     – 50% of showing treshold: Th, V and W;
     – 75% of showing treshold: Ti.

 

Significant Thresholds
An analysis yielding a content that differs statistically from the entire geochemical database (mineralized and non-mineralized rocks), but that is still below the anomalous threshold. The 1-sigma of the normal distribution, namely the 84th percentile, was calculated. The rounded results are considered appropriate for all elements, with the exception of Be, for which a cut-off value at 10 times the detection limit was preferred, and U, for which a cut-off value at 10% of its anomalous threshold was found to be more consistent.

 

North (green) and south (orange)

 

Element Significant Treshold Anomalous Treshold Showing Treshold Unit
Ag 1 3 5 ppm
Au (north) 35 300 1000 ppb
Au (south) 35 300 500 ppb
Be 10 100 360 ppm
Co 100 1500 5000 ppm
Cr 400 2000 6800 ppm
Cu (north) 125 500 5000 ppm
Cu (south) 125 500 1000 ppm
Platinoids (PGE) 70 300 1000 ppb
Fe 110 000 200 000 300 000 ppm
Li 30 300 1160 ppm
Mn 1700 30 000 100 000 ppm
Mo (north) 5 450 1500 ppm
Mo (south) 5 450 600 ppm
Nb 20 100 350 ppm
Ni 150 1500 2500 ppm
Pb (north) 25 1500 5000 ppm
Pb (south) 25 1500 3000 ppm
Pd 50 200 500 ppb
Pt 20 200 500 ppb
Rare earth elements (REE) 250 1500 1700 ppm
Rh 10 40 100 ppb
Sb 10 3000 10 000 ppm
Sc 50 100 150 ppm
Sn 10 300 1000 ppm
Ta 5 50 164 ppm
Th 10 200 440 ppm
Ti 8000 75 000 100 000 ppm
U 30 300 425 ppm
V 300 700 1400 ppm
W 10 500 1000 ppm
Y 50 250 790 ppm
Zn (north) 150 2000 7500 ppm
Zn (south) 150 2000 3000 ppm
Zr 250 1000 3700 ppm