Ophir announced magnetic results on January 12, 2020. The survey was performed with ground magnetometers on 100 meter line spacing. The purpose was to characterize the fault zone host to the Breccia epithermal system. Ophir reports the survey was successful in outlining a magnetic low corridor coincident with “Breccia”. Importantly, this magnetic low corridor indicates “Breccia” may continue to both the north and south under cover, across the entirety of the property. This would more than double the known strike extent.
The survey also identified a strong magnetic anomaly at the south end of the grid. 3-D inversion estimates depths at about 800 meters (see Fig 2). The magnetic anomaly may be a porphyry intrusion, and source of heat and fluids that mineralized the Breccia zone, supporting Ophir’s interpretation that the Breccia Gold Property represents the upper levels of a low-sulphidation epithermal gold system.
Breccia is the principal target on which Ophir is focused on, however, the magnetic data is worthy of additional comment (See my interpretive annotation on the accompanying magnetic map).
As noted in the news release, a magnetic low structure corridor is coincident with the Breccia zone. The continuation of this magnetic low corridor suggests the Breccia Zone could extend for more than twice the known distance. Interestingly, this magnetic low corridor appears to connect at the south end of the grid, to a large magnetic anomaly that may be a porphyry intrusion.
A magnetic high anomaly is spatially associated with a large 500m x 500m gold soil anomaly near the north end of the property. A magnetic low coincident with the core of the large gold soil anomaly may represent magnetite destructive alteration that accompanied gold mineralization, or perhaps a splay off the main Breccia Zone.
A magnetic high anomaly is spatially associated with the argillic alteration zone and gold soil anomaly situated on the Musgrove Mine trend, east of the Breccia Zone.
A large intense magnetic low shell surrounding a magnetic high core is located on the south end of the grid. This magnetic anomaly may represent a porphyry that provided the heat, hydrothermal fluids and gold in the Breccia Zone. If so, the porphyry itself may also be mineralized. Interestingly, this magnetic signature is typical of more oxidized gold rich porphyries. Perhaps the central magnetic high represents secondary magnetite, potassic alteration and bornite-gold mineralization, and the outer magnetic low shell represents phyllic alteration, variable chalcopyrite-gold mineralization and magnetite destruction?
Another magnetic low corridor is situated to the west of the Breccia Zone and under cover of the Challis volcanics. This magnetic low corridor also appears to emanate from the large magnetic anomaly at the south end of the grid. Perhaps this magnetic low corridor is host to a blind epithermal system similar to the Breccia Zone?
Continuing exploration on Ophir’s property is revealing much larger potential than originally envisioned, with as many as five targets to advance and explore. Success on the Breccia Zone will open the door to develop and explore additional targets.
Disclosure: I have taken an initial position in the shares of OPHR.V and may buy or sell at any time and without notice. I have no affiliation with OPHR.V of any kind. The commentary is entirely my opinion based on my research and experience. Note: OPHR provided 1st derivative magnetic map