Preliminary Work
The two magnetic grids from GDS 1004 and 1100 were joined
The grids from the two EM systems cannot be easily joined, due to the different systems and output units. However, using the gate times from both systems and comparing the signals, the grids were joined for internal use only. Since GDS1004 was only X-component the joined EM grids could only be X-component
2018 Drill Core Program
Rock samples from 4 drill holes completed in 2018 by Spruce Ridge, holes CR18-01, 02, 03, and 04, were used to determine average specific gravity and magnetic susceptibility of the intersected rock units and to run laboratory tests comparing recovery differences using two different analytical methods.
Specific Gravity
Rocco from the 2018 drilling had specific gravity (SG) measurements made at regular intervals using the “weight in water versus weight in air” relative density method. Average SG for mafic volcanic rocks was 2.67 (N=60) and average SG for serpentinized ultramafic rocks was 2.66 (N=436). Specifically, with respect to the ultramafic rocks, average SG for intervals grading over 0.25% Ni was 2.61, for intervals between 0.20 Ni and 0.25% Ni was 2.62, and for intervals less than 0.20%, Ni was 2.63. The process of serpentinization involves the introduction of water into the rock, resulting in a substantial volume increase. The low average SG of the CUC ultramafic rocks bracket 2.66 bracket implies a high degree of serpentinization.
Magnetic Susceptibity
Magnetic susceptibility readings were collected along the drill core from the four drill holes completed in 2018. On the basis of more than 1400 readings, it was shown that the ultramafic rocks (average 129 units) were sometimes 100 times higher than host. Mafic volcanic rocks (average 0.72 units). The serpentinized rocks are extremely magnetic relative to the host rocks and non-serpentinized rocks. Ultramafic rocks, a result amplified by the serpentinization of olivine which releases iron to form magnetite.
Geophysical Signatures
Looking for Ni(Co-Cu-PGE) – e.g. Crawford – magnetic high, may be conductive, gravity gradients? (serpentinization against unaltered ultramafic rocks)
Looking for Au deposits – magnetic lows, only conductive if associated with sulphides, gravity high.
- We can expect conductors associated with graphitic material – as noted from drill holes from the Crawford Project and the Fortune claims.
- We can expect magnetic highs that are associated with mafic, ultramafics, diabase dykes and iron formation.
- We can expect magnetic lows that may be associated with felsic material, graphitic zones, shear zones, magnetic lows that are associated with Au mineralization.