The Second Basin Gossan area is underlain by Devonian to Permian marine sedimentary and volcanic rocks of the Stikine Assemblage which area overlain by marine sedimentary and volcanic rocks of the Upper Triassic Stuhini Group. Lower Jurassic rock of the Hazelton groups overly the Stuhini rock.
The volcanic and sedimentary sequences were intruded by the Tertiary-Cretaceous Coast Plutonic Complex. A wide variety of intrusive phases are present including granodiorite, quartz monzonite and diorite. Small satellitic plugs from the main batholith are important for localizing mineralization.
The predominant lithologies on the property consist of marine sediments, volcaniclastics and volcanic flows. The marine sediments consist of argillites, argillaceous siltstones and siltstone with some quartzite, greywacke and carbonates. These sediments are interbedded with contemporaneous marine volcanics ranging from rhyodacite to basalt in composition. Volcanic facies include crystal fragmental tuff, lithic tuff, breccias, agglomerate, flows and sills.
Low grade regional metamorphism has occurred within the marine sediments which contain abundant chlorite. Foliation is usually con- formable with the bedding. Fault and shear zones trend 135 degrees and about 045 degrees with andesite and basalt dykes following the 045 degree structures and felsite dykes related to the 135 degree structures.
Locally, mineralization appears to be associated with base metals in distinct quartz vein systems. Pyritization, of up to 15 per cent, is commonly associated with silicified zones. Upon weathering, these zones develop moderate to intense gossans composed of hematite, goethite, jarosite and pyrolusite.
In the Second Basin Gossan area, there are several shears in the metasediments. A 135 degree trending shear hosts a hornblende por- phyry dyke while 045 degree trending shears are silicified and host abundant quartz and calcite veins.
In 1987 a sample from a 12 centimetre wide quartz vein with pyrite, chalcopyrite, galena and sphalerite assayed 2.16 grams per tonne gold, 288.9 grams per tonne silver, 0.12 per cent copper, 0.035 per cent lead and 0.031 per cent zinc (Assessment Report 16957). This quartz vein is within pyritized rhyodacitic tuff and metasediments comprised of altered argillite, siltstone and fine-grained sandstone.
Work History
The first work recorded on the ground was performed by Anaconda Canada Exploration Ltd. for a Skyline Exploration Ltd., Placer Development Ltd. and Anaconda joint venture on the Burnie 14, Reg 10 and Stanley 7 claims around 1983. This program was carried out to follow-up on a helicopter-borne geophysical survey and consisted of geological mapping and limited trenching, prospecting, reconnaissance ground geophysics and stream sediment sampling. A total of 28 heavy mineral stream sediment samples and 20 rock samples were collected during the course of this program. The trenching and the five associated rock samples and the ground geophysics were conducted over an area just west of the present Eldorado claims. Anaconda’s work defined a silver-copper-lead-zinc-iron carbonate vein showing off the present Eldorado property with anomalous copper in heavy sediments in First Basin and anomalous gold in heavy sediments in Second Basin.
In 1987, Androne Resources Ltd. completed an exploration program on the Burnie 1-4 and Dan l-3 claims. Their work was comprised of geological mapping and prospecting (139 samples), silt sampling (56 samples) and contour soil sampling (272 samples). This program identified the Grace 2 showing, a northwest-trending shear zone with silicification and pyritization with malachite and which yielded significant gold, silver and copper assays. Androne also discovered the Grace 1 showing, a similarly-trending and mineralized shear zone, also with chalcopyrite and azurite.
Pezgold Resources Corp. conducted an exploration program in 1988 that was, in part, a continuation of the 1987 program that was halted due to adverse weather conditions. This program entailed grid-based soil sampling and VLF-EM surveys over the Grace showings and four trenches totalling 37 metres over the Grace 2 showing. A total of twelve chip samples were collected from two of these trenches. Results from these trenches were erratic and discouraging with maximum values of 11.9 grams per tonne gold and 1.5 per cent copper over 20 centimetres. The soil survey identified numerous, multi-station, but discontinuous anomalies with the strongest response in gold and base metals in the northern part of the grid (near the Grace 1 showing) and the strongest response in gold and silver in the southern part of the grid. A total of 5.3 line-kilometres of VLF-EM surveying was conducted over this same grid. The most pronounced anomaly outlined by this survey was associated with the Grace 1 showing. Several samples were taken at the Second Basin North showing.
The Burnie and Dan claims were allowed to lapse in the fall and winter of 1994 and were restaked in 1995 by David Javorsky as the Eldorado l-4 mineral claims. Javorsky carried out a limited program of prospecting in the Second Basin area including heavy mineral stream sediment sampling, and re-evaluation of the previous trenching.
In 1996, a total of 115 soil samples and 21 rock samples were collected by Golden Band Resources Inc on the Eldoradao claims (Assessment Report 25009).
During 2009 through 2011, Skyline Gold Corp. completed programs of prospecting, geochemical (rock and soil) sampling, trenching, airborne and ground geophysical surveys and 23 diamond drill holes, totalling 5676 metres, on the area as the Iskut property.
