The Dry Pond occurrence is located northeast of Dybrough Peak, northwest of the Finlay River and approximately 8 kilometres east-southeast of the east end of Black Lake.
Regionally, the area is underlain by Devonian to Permian Asitka Group meta-dacite tuff and marble and Upper Triassic Stuhini (Takla) Group basaltic andesite. Lower Jurassic Toodoggone Formation (Hazelton Group) dacite occurs to the north. Jurassic Black Lake plutonic suite granodiorite and quartz monzonite dikes and plugs cut these rocks. Intense hornfels occurs within volcanic rocks around the granodiorite and large-scale faults cut the intrusive and volcanic rocks in a northwest orientation.
The occurrence area is located at the intrusive contacts of the Black Lake stock with two inliers of volcanic and sedimentary rocks of the Asitka Group. Porphyritic quartz monzonite and medium to coarse-grained equigranular hornblende granodiorite of the Duncan Lake stock underlie a 1500- by 3000-metre xenolithic slab of Asitka siltstone and mafic tuff that strikes westerly and dips gently to the northeast. Intrusive rock southeast and west of Dry Pond is quartz monzonite porphyry and hornblende granodiorite outcrops to the south and southwest of Dry Pond. A second, wedge-shaped block of Asitka siltstone, tuff and minor limestone, 5000 metres long, is intruded by felsic granitic dikes with a northwesterly trend. The northeastern contact of this Asitka block with Takla pyroxene basalt flows is a fault contact along the strike of the Saunders-Wrich fault. In the northern part of the property, Takla basalt is stratigraphically overlain by Toodoggone dacitic crystal tuff that is also dextrally offset by the Saunders fault. A group of three monzonite porphyry dikes, 20 to 60 metres wide, intrude marble, siltstone and mafic tuff of the Asitka Group 1000 metres north of Dry Pond. Northeastern contacts of the northwest-striking and steeply dipping dikes are in reverse fault contact with their Asitka hostrocks. The northernmost dike is also in dextral strike-slip contact with Takla basalt across the Saunders-Wrich fault.
Asitka mafic tuff, well exposed in the canyon of Pond Creek draining Dry Pond, strikes northwest and dips moderately southwest, and is cut by faults and fractures parallel to the dominant northwesterly trend of the dyke swarm and the Saunders fault. Several of these faults and fractures are mineralized with quartz-pyrite-chalcopyrite.
Locally, two areas of mineralization (Dry Pond Canyon and Northwest [Dry Pond] Skarn) have been identified.
The Dry Pond Canyon zone comprises a 250-metre-wide zone of veins and mineralized fractures that strike 110 to 135 degrees from the north side of Dry Pond to a fault contact between quartz monzonite and Asitka tuff in the canyon of Pond Creek. Veins are dominantly composed of quartz, pyrite and chalcopyrite, lesser molybdenite, and rare sphalerite and galena. Pink potassium feldspar and epidote, and abundant disseminated pyrite accompany veins in tuff and siltstone. Veins in the northern part of this zone, in a southeast-flowing branch of Pond Creek, contain massive chalcopyrite and pyrite, and visible molybdenite in the pyritized contact zone of a monzonite porphyry dike.
Mineralized fractures in tuff in the canyon could be interpreted to extend this vein zone to the northeast another 1000 metres in width. Although largely obscured by overburden, scattered outcroppings indicate vein mineralization occurs over an area of 1500 by 1500 metres following the trend of the Asitka inlier.
The Northwest (Dry Pond) Skarn zone is located approximately 500 metres northwest of the Canyon zone and comprises skarn zones and lesser veins in a body of marble near the northeastern contact of the wedge-shaped Asitka inlier. Skarn is developed at the contacts of monzonite and quartz monzonite dykes with marble. Most skarn exposures are associated with the middle member of a family of three dikes, over a strike length of 300 metres. Prograde skarn is an assemblage of pyrite, magnetite, chalcopyrite and lesser sphalerite, bornite and galena with green diopside and orange to yellow-green garnet. Garnet and pyroxene are retrograde altered to brownish-green actinolite, epidote and chlorite. Sulphide-rich skarn is oxidized to limonite, pyrolusite and malachite-azurite. The skarn zone has been partially exposed over an area of approximately 50 by 25 metres.
A second skarn zone in the Asitka inlier occurs 1500 metres southeast of the first zone, in a lens of marble exposed on a ridge near the faulted off southeastern limit of the block. Mineralization is mainly quartz-pyrite-chalcopyrite in sheared marble adjacent to the Saunders fault.
A positive magnetic anomaly (800 by 400 metres in dimension) is reported to possibly represent a porphyry copper system that may be sourced beneath overburden west and southwest of the skarn zone and north of the Dry Pond Canyon zone. Another, smaller magnetic anomaly (200 by 200 metres) reportedly appears to be sourced beneath cover northeast of the copper showings at the junction of Dry Pond canyon and the main creek.
In 2003, samples from Dry Pond Canyon zone yielded up to 5.115 per cent copper, 0.03 gram per tonne gold and 69.3 grams per tonne silver over 0.3 metre, whereas samples from hand trenches on the Northwest (Dry Pond) Skarn zone yielded up to 0.12 per cent copper, 0.56 per cent lead, 0.36 per cent zinc, 0.15 gram per tonne gold and 40.4 grams per tonne silver over 2.0 metres with grab samples yielding values of up to 14.00 grams per tonne gold and 1069.6 grams per tonne silver from oxidized, iron-rich skarn material (Assessment Report 27429).
Work History
The area has been historically explored in conjunction with the Rega (MINFILE 094E 003, 004 and 005) occurrences and a complete early exploration history of the area can be found there.
Refer to the Pine (MINFILE 094E 016) occurrence for details of the Pine property, which contained the Dry Pond occurrence from the late 1990s to 2014. Exploration work included programs of rock and soil sampling, geological mapping and airborne geophysical surveying. Also see the Electrum (MINFILE 094E 125) occurrence for details of historical property ownership and related occurrences, and related VIP occurrences: MINFILE 094E 047, 048, 049 and 129.
In 2003 approximately 120 rock samples were taken on the northeast side of Drybrough Peak by Stealth Minerals Ltd as part of a large exploration project on their Pine property. Three discreet areas containing significant copper, gold and silver values were identified and referred to as the west trenches (Riga 24 [MINFILE 094E 005]), Dry Pond Canyon and northwest skarn zones.
During 2016 through 2018, Amarc Resources Ltd. completed programs of soil and rock sampling, geological mapping, 115.0 line-kilometres of ground induced polarization surveying and 1940.0 line-kilometres of airborne magnetic surveying on the area as the Joy property.
