Post by
diabase1 on Jul 07, 2023 7:05am
Pharand II (4)
Geology
Taken from RT Mineral's website:
"At the extreme eastern edge of the Northern Swayze Greenstone Belt (a fault bounded remnant wedge), the Hanrahan assemblage continues eastward into Pharand Township. The assemblage is completely surrounded by the Kenogamissi Batholith and ends (fault truncated) within Childerhose Township. Previous exploration activities encountered well mineralized pyritic pyroxenite/gabbroic ultramafic intrusive bodies with elevated platinum and palladium values contained within the Hanrahan assemblage of volcanic rocks".
Of all the reports etc. that I've read on the Pharand II property, I don't recall reading anything on pyroxenite being located on the property. I could be wrong!! The closest that I came to was; Sample B19 had a very high MgO) content of 12.7% and mafic phenocryst (pyroxene?) were found in this sample. This is further evidence that some mafic/ultramafic intrusive units possibly exist in this area within the volcanics (42A04NE8554/42A04NE8554). However, 12.7% MgO is not very high to be called an ultramafic intrusive rock and the pyroxene? was questioned!! Maybe the rock is a komatiitic basalt!!
E. Mord described the rock types within the property as follows; "The prospecting in Pharand Twp. (42A04NE0008/42A04NE0008) took place within a small area of greenstone situated between Pharand Lake and Pharand Creek. This outlier is believed to be a portion of the Swayze Greenstone Belt. The rocks in this small area consist of intercalated mafic and felsic volcanics intruded by both mafic (gabbroic) and felsic plugs of variable composition. Later, north-south trending diabase dykes crosscut, all of the units mentioned above".
Geology Map 32D points out that parts of the Pharand I property may have pyroxenite, but the Pharand II property has only light and dark schist, many porphyry dykes and rhyolite.
Map P.3511 shows intermediate to felsic metavolcanic rocks/intrusions.
Map 2205 shows an east west trend of felsic metavolcanics through the northern part of the property.
Airborne Geophysics
The only airborne survey that I'm aware of, that has covered the Pharand II property, is the Electromagnetic and Magnetic Survey carried out by the Ontario Geological Survey (Map 81380). The predominate picture here shows a north-south diabase dyke dominating what appears to be a weak east-west magnetic anomaly, located in the northern part of the property. In the southern portion of the property, any east-west magnetic trend is not discernible, because of the overpowering influence of the north-south diabase dyke.
However, there were a few extremely weak 1-2 channel airborne electromagnetic anomalies intercepted within the western region of this property. Two of them line up and strike east-west (Map 81380). I have not seen the EM profiles, but could these EM responses be associated with a bedrock source? The GEOTEM EM system has the capabilities to penetrate at least 300m deep. However, if the zinc content is much higher than the other metals, then it's possible that a weak EM response may be seen.
There were no strong EM conductors intercepted within any parts of the property. Because of the disseminated nature of the sulphides within the property, a frequency domain airborne system would probably have been more conducive to intercepting this style of mineralization. A magnetotelluric system may be one of those systems.
Of importance is the moderate gravity anomaly that is indicated on Map 2594. The center of the anomaly is located on or near the west shore of Deacon Lake. This puts it on or near the east property boundary of RT Mineral's Pharand II property. It exhibits an intensity of approximately 45 mGal. The anomaly shows up much better on the Shaded Image of the Vertical Gravity Gradient (Map 2598). It is suggested that this gravity anomaly is related to a specific rock type, rather than to an underlying ore deposit. Any ore deposit, if there is any, would be masked by the overall gravitational strength of the hosting rock type.
Ground Geophysics
The VLF system is quite useful when it comes to looking for gold within shear zones. However, when it comes to intercepting disseminated sulphides within mafic/ultramafic intrusions, the VLF system would prove to be the wrong method. Also, the VLF system has its limitations, when it comes to depth of penetration. Therefore, either a frquency IP survey or an MT survey would be more in line for the style of mineralization being investigated for. I can understand E. Mord using the VLF system, because he was looking for gold. If RT Minerals is looking for low grade Ni-Cu-PGE deposits, then a deeper looking system is necessary. We know there are patchy gabbro outcrops within the property, but I also suspect that a bigger gabbroic body may be located at depth. A gravity survey may also reveal whether or not a deeper body of mafic/ultramafic intrusive actually exists at depth.