Seabridge tests porphyry target at Iskut
Geophysics refined KSM-like copper-gold target for drilling North of 60 Mining News – August 13, 2021
Last updated 8/19/2021 at 3:47pm
Seabridge Gold Inc. Aug. 11 reported that a magnetotelluric geophysical survey carried out at Iskut earlier this year has further refined targets for a roughly 3,200-meter drill program testing for a gold-copper porphyry mineral system similar to those on the company's nearby KSM project in British Columbia's Golden Triangle.
Situated about 30 kilometers (19 miles) west of Seabridge's world-class KSM gold-copper project, Iskut is home to the historical high-grade Johnny Mountain gold-silver-copper mine.
Seabridge says its intensive use of geophysical tools, mapping, sampling, and preliminary drilling over the past four years continues to indicate the potential for a large gold-copper porphyry system below the Quartz Rise lithocap southeast of Johnny Mountain. Lithocaps are typically formed above deeper porphyry systems, which is the larger gold-copper deposit Seabridge is seeking at Iskut.
The company believes that extensive surface expression of gold and copper geochemistry and alteration at the Quartz Rise Lithocap was formed by a significant, undiscovered gold-copper porphyry system at depth.
The company says the results from an 11-hole drill program carried out last year to test geophysical anomalies below the Quartz Rise lithocap are consistent with the alteration halo of such a large porphyry system.
This includes mineralized intervals of up to 158 meters averaging 0.16 grams per metric ton gold and 0.16% copper, indicating that drilling to date is in the outer portions of the porphyry system Seabridge is pursuing.
The drilling also tapped shorter sections of higher-grade mineralization, including 31.8 meters averaging 0.62% copper.
The intrusive rocks encountered during the 2020 drilling have been age dated to be within the timeframe of the KSM mineral system. Seabridge's 2021 program got underway in June with a magnetotelluric geophysical survey and now continues with roughly 3,200 meters to test the porphyry target indicated by previous exploration and further refined by this year's geophysics.
"Seabridge acquired the large land package at Iskut because of its many characteristics similar to our giant KSM project. Since the acquisition, we have refined our target ideas with additional data and experience from KSM," said Seabridge Gold Chairman and CEO Rudi Fronk. "The structural complexity of this terrain made us proceed methodically and we now have multiple lines of evidence that point to a coherent target for the gold-copper porphyry source."