Regionally the Aspen showing occurs within the Intermontane Belt, underlain dominantly by Lower to Middle Jurassic volcanic and sedimentary rocks of the Hazelton Group. These assemblages are overlain by the Upper Cretaceous to Lower Tertiary Ootsa Lake Group and Miocene plateau basalt. Intruding Lower Jurassic rocks of the Hazelton Group in the northeastern part of the map sheet is a belt of granodiorite, diorite and quartz diorite plutons of the Lower Jurassic Topley intrusive suite. Felsic plutons of probable Cretaceous age intrude both Lower and Middle Jurassic Hazelton strata.
The Aspen showing comprises molybdenite with minor chalcopyrite, pyrite and pyrrhotite in Jurassic Hazelton Group rhyolite and andesite near the contact with a Cretaceous granodiorite pluton.
In 2013, Redhill Resources drilled 13 drillholes south, southeast and northeast of the plotted C showing area. An interval of intensely altered stockwork/breccia from hole A13-6 yielded 0.2645 copper, 42 grams per tonne silver and 1 gram per tonne gold over 6.02 metres (Assessment Report 34423). The 2013 drilling program which in most part targeted untested IP anomalies confirmed the presence of extensive propylitic (chlorite +/- epidote +/- calcite) and potassic (biotite +/- K-feldspar) alteration zones accompanied by weak copper, silver, gold and arsenic mineralization.
See CH (093F 098) for further details.
Rio Tinto Canadian Exploration Limited filed assessment reports for the years between 1969 and 1975. Except soil sampling, magnetometer, VLF, airborne EM and IP surveys were done in this area in the late 60’s and early 70’s mostly by Rio Tinto on their C claims which covered the April (CH) showing (093F 060) area and the C (Aspen) showing (093F 004) area. IP surveys identified extensive zones of high chargeability (Assessment Reports 2097, 2568, 2683 and 5524). In 1969, the Rio Tinto carried out geological mapping, magnetometer and induced polarization surveying over 26 line-kilometres, collection of 1000 soil samples, 7.6 metres of trenching, and 686 metres of diamond drilling. Four zones of high chargeability were found.
In 1970, Rio Tinto completed more geological mapping, 84 line-kilometres of induced polarization surveying, and 5 line-kilometres of magnetometer surveying. They also collected 1272 geochemical samples, dug nine trenches, and completed 340 metres of diamond drilling. The soil sampling showed scattered medium to strong copper-molybdenum anomalies and weak lead-zinc-nickel anomalies.
In 1971, the assessment work by Rio Tinto included: 316 square kilometres of airborne magnetometer surveying, and 256 metres of surface diamond drilling.
In 1980, on the April and May claims, Granges Inc collected a total of 389 soil samples which resulted in the discovery of a coincident silver, lead, zinc, copper anomaly and a second more diffuse to the west. In 1984, Granges drilled a total of three (3) holes totalling 156.67 metres. In 1981, Granges conducted an airborne geophysical survey which did not outline any EM anomalies on the Chutanli Lake project, though several magnetic trends were located.
In 1991 and 1992, regional geochemical till sampling program for Cogema Resources occurred in the vicinity of Chutanli Lake. The samples were variously anomalous in gold, silver, arsenic, antimony, copper, lead, zinc and molybdenum.
In 1990, Placer Dome Inc. collected 248 soil samples, as well as conducting a 3.64 kilometres magnetometer and 3.7 kilometre VLF-EM survey on two grids on their CH claims. The Main grid was located about 1.3 kilometres east of the plotted location of the April showing and the Road grid located about 400 metres northeast of the plotted location of the C showing. The Main grid is just west of the C showing. Both grids contain coincident copper-gold - molybdenum soil geochemistry. Orvana later reported (Assessment Report 25069) that drilling totalled 22 drill holes on the CH property that included the previous drilling by Rio Tinto and newer drilling by Placer (in 1992). This drilling intersected low grade copper porphyry target. Placer drilling concentrated on IP chargeability high and magnetic high areas. Mineralization consists of up to 5 per cent quartz and quartz-carbonate stockwork with associated magnetite-pyrite-chalcopyrite and is related to various alteration types within volcanic and intrusive rock. Pyrite and chalcopyrite occur in veins and microveins in the volcanics, on fracture surfaces and as fine disseminations in intrusive rocks. Malachite occurs along fracture planes. Copper-gold rich mineralization is intersected in drill holes
In 1996, Orvana Minerals Corp. collected 111 rocks from their CH property which covered the April and C MINFILE showings. Orvana reported that the April showing represents epithermal, vein type mineralization. The April showing is approximately 2 metres wide and over 15 metres long.
From 2008 to 2011, four assessment reports were filed by Omega Explorations on behalf Jacqueline A. McLeod on their Porphyry property. Work in the April showing area, and to the east toward the C (Aspen) showing, consisted mostly of soil sampling with minor ground magnetometer and rock sampling. The new MINFILE prospect occurs in that area between the April and the C (Aspen) showing in the CH prospect area.
In 2011, Ron Bilquist on his Chutanli 1 to 3 where 3 days were spent prospecting. All old and new logging roads were traversed with the location of outcrops, glacial outwash and till noted. A total of 9 rock samples were taken and 13 geological way points were recorded. Prospecting discovered mineralized float over a presently defined area of about 500 meters by 250 metres. Finely disseminated molybdenite with minor chalcopyrite was noted in angular chlorite altered float. One other sample of angular subcrop of chlorite altered diorite had malachite and possible bornite with anomalous gold.
In 2013, Redhill Resources conducted a drilling program on the Aspen property which consisted of 13 diamond drill holes totaling 1785 metres of BTW size core. The Aspen property covered much of the CH property area, including the April and C showings documented in MINFILE. The 2013 drilling program mostly targeted untested IP anomalies.
Redhill Corp reported (Assessment Report 34423) that anomalies on their properties had been previously tested by 30 holes but the results (except a few 1997 holes (Orvana?)) were not available. Redhill reported that the bulk of historical drilling was done within a zone of copper +/- gold mineralization called CH zone, which used to be a part of historical CH property. This zone is plotted by Redhill as being 1 kilometre east of the April showing.
Redhhill also conducted a program of sampling on their larger claim group. A total of 49 rock, 1461 soil, 62 biogeochemistry samples, and 14 silt samples were collected. The focus of the 2013 sampling program on Aspen property was an area between Chutanli and Brewster Lakes. The 2013 sampling program detected 3 soil anomalies.