Completion Of Geophysical Surveys At Sombrero Butte Porphyry Copper Project
CALGARY - Copper Fox Metals Inc. and its 100% owned subsidiary, Desert Fox Sombrero Butte Co. reported on the recently completed DC Resistivity - IP Chargeability (DCIP) and Magnetotelluric (MT) geophysical surveys on the Sombrero Butte porphyry copper project. The Sombrero Butte project is located approximately three kilometers south of the Copper Creek porphyry copper project currently undergoing exploration/development by Faraday Copper Corp.
The primary objective of geophysical program was to obtain a subsurface chargeability/resistivity model to be used in conjunction with updated geology and alteration models and distribution of copper-molybdenum mineralization to transition the project, if possible, to the drilling stage.
Elmer B. Stewart, President & CEO, said, "The preliminary results of the geophysical program identified anomalous chargeability on all seven lines surveyed representing an area measuring approximately 2,400 meters (m) in an east-west direction and ranging from 500m on L0000E to 2,500m wide on L0800E in a north-south direction. The spatial correlation between the anomalous chargeability and the previously announced limonite alteration zone hosted in moderate to intensely altered Laramide age Glory Hole Volcanics continues to support our interpretation of the presence of a large porphyry copper system within the Sombrero Butte project. While these preliminary results are encouraging, receipt of the final geophysical report is required before any conclusions can be made as to the significance of the anomalous chargeability/resistivity signature."
In porphyry copper deposits, anomalous chargeability signatures are typically interpreted to indicate zones of potential mineralization by showing high chargeability values associated with disseminated sulfide minerals like pyrite and chalcopyrite. Resistivity data is used to interpret various alteration patterns associated with porphyry copper systems, for example, areas of high chargeability associated with high resistivity could indicate the presence of sulphide mineralization associated with advanced argillic alteration whereas high chargeability associated with moderate to low resistivity could be indicative of sulphide mineralization associated with phyllic (quartz-sericite-pyrite) alteration. Both styles of alteration occur within the project based on the 2024 mapping program.
For the purposes of this preliminary interpretation, anomalous chargeability is defined as greater than 20 mrads. Resistivity readings between 30-400 ohms are interpreted to represent low-moderate resistivity and readings greater than 1,000 ohms represent high resistivity. The transition from low-moderate to high resistivity generally occurs rapidly over short distances.
On the east side of the project represented by L1600E (see Figure 1), L2000E and L2400E, the upper portion, 200m of the survey lines, is characterized by high chargeability and low-moderate resistivity. At a depth of 400m below surface, anomalous chargeability (> 20 mrads) occurs over a distance of 1,700m on L2400E and increases to 2,500m on L1600E. Similarly, on L2400E the anomalous chargeability is accompanied by low-moderate resistivity whereas on L2000E and L1600E the anomalous chargeability is accompanied by zones of high resistivity (>1,000 ohms), separated by a zone (estimated to be approximately 1,000m wide) of low-moderate resistivity. On L1600E and L2000E anomalous chargeability and associated high resistivity have been surveyed to a depth of 800m below surface and remain open at depth. Ground checking on L1600E indicates the anomalous chargeability occurs within an area of limonite alteration (quartz-sericite-limonite veinlets, limonite filled fractures and pervasive intense limonite staining) hosted in moderate to intensely altered, Glory Hole Volcanics. In fresh rock, sporadic quartz-pyrite-chalcopyrite veinlets, pyrite veinlets, chalcopyrite veinlets, and fractures occur.