Chalcedonic quartz vein breccia
Virtual Museum ID: 19-D28-05
Chalcedonic quartz vein breccia
The information listed below relates to the current holding location or collection that the sample is from, and whether the item is viewable at that location or is part of a private collection. Coordinates are given as guides, and we remind you that collecting specimens from these locations is not allowed. Caution is advised visiting such sites and Below BC assumes no responsibility for any injuries or trespassing charges that may occur as a result of the viewer entering these sites.
Original Collection:Smithers Exploration Group (SEG)
Sub Collection:Epithermal Textures
Virtual Museum ID:19-D28-05
Date Added to VM:2019-08-21
Sample Origin:Nechako, as above, Water Two
Datum:10 (NAD 83)
Primary Features:Chalcedonic quartz vein breccia
Primary Mineral Formula:SiO2
Advanced Geological Information
The following section provides geological data relating to the specimen or the site it was collected from, when available. Information has been obtained from various sources including private and government datasets but may not be up to date. Any geological time periods or ages listed often relate to the primary geology of the area, and may not be the actual date of an event such as mineral formation.
Geological Formation:Hazelton Group
Geological Period:Lower to Middle Jurassic
Minfile ID:093F 045
The Wolf prospect is located about 130 kilometres southwest of Vanderhoof and consists of 198 claim units in 13 claim blocks between Cow Lake to the south and Entiako Lake to the northwest.
The claims were staked in 1983, by Rio Algom, to cover prominent knobs of hydrothermally altered felsic volcanic rocks that crop out east of a silver-zinc-arsenic-molybdenum lake-sediment anomaly. Lucero Resource Corporation worked the property from 1986 to 1996. The property is currently explored by Metall Mining Corp. under option from Lucero Resource Corporation.
The region in which the showing occurs is underlain dominantly by Lower to Middle Jurassic volcanic and sedimentary rocks of the Hazelton Group. These assemblages are overlain by the Upper Cretaceous to Oligocene 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 Wolf occurrence is hosted by Mid-Eocene Ootsa Lake Group felsic flows, tuffs and subvolcanic porphyries. Poorly consolidated mid-Miocene sedimentary rocks, intersected in drilling, unconformably overlie the volcanic succession. The palynomorph assemblage in these rocks correlates closely with the Fraser Bend Formation. Mineralization and alteration are structurally controlled.
Mineralization occurs in northerly trending quartz (carbonate) veins (Lookout and Pond zones), siliceous stockworks (Blackfly, Chopper Pad and East zones) and hydrothermal breccia zones (Ridge zone) and as a stratabound unit of pervasively silicified and brecciated rhyolite and tuffaceous sediments (Ridge zone) capped by a maroon quartz feldspar porphyry sill. Chalcedonic colloform banding, comb structures, drusy cavities and bladed quartz textures (silica replacement of original calcite or barite) are common.
The geological setting, vein and breccia textures, alteration and metal distribution patterns resemble those of a low sulphur, adularia-sericite type hot-spring or silicified stockwork deposit. Native gold and electrum of micron size are associated with pyrite, chalcopyrite, aguilarite, naumannite and acanthite in silicified zones. At least 8 distinct phases of repeated, episodic and explosive stockwork veining and brecciation are recognized in the silicified zones (Andrew, 1988). Fluid inclusion studies indicate that the veins are epithermal, deposited at depths of less than a kilometre by low salinity, low carbon dioxide boiling fluids at temperatures from 170 to 270 degrees Celsius. Oxygen and hydrogen isotope compositions imply that water to rock ratios at Wolf were high (0.3 to 0.9).
The highest grades of mineralization appear to occur in zones that have undergone repeated episodes of brecciation and silicification. Better gold grades are associated with grey to brown banded chalcedonic silica and very fine grained disseminated pyrite. The most encouraging results to date have been at the Ridge zone, where trenching across the zone yielded 8.49 grams per tonne gold and 42.21 grams per tonne silver over 7.5 metres (Fieldwork 1993, page 47).
The 1992 diamond drilling program on the Wolf claims successfully identified a significant zone of epithermal style gold mineralization at the Ridge Zone. It consists of a shallow dipping zone of strong silicification, banded veins and hydrothermal breccias localized close to the lower contact of a rhyolite porphyry sill. Gold grades of approximately 2 grams per tonne occur over an area of approximately 300 by 300 metres (in plan) with an average thickness of about 9 metres. Significant areas of silicification and anomalous gold values were also identified at the Blackfly Zone (holes WF92-16 and 17) (Assessment Report 23076).
Other zones of interest include the Pond, Lookout, Chopper Pad and East Grid zones. The Pond zone is a 350 by 30 to 40 metre wide silicified area located south and east of the Ridge zone. The zone is underlain by a variably silicified and quartz veined feldspar-quartz porphyry. The Lookout zone is a 150 by 30 to 40 metre area of irregular chalcedonic quartz veining cutting maroon crystal tuff. The best single assay from this zone was 2.1 grams per tonne gold and 20.5 grams per tonne silver (Property File Rimfire Lucero Resources Ltd., 1987). The Chopper Pad and East Grid zones cover areas of silicified rhyolite that correspond to broad silver anomalies.
In 1982, regional lake sediment surveys were conducted by Rio Algom Explorations returned an anomalous sample in silver, zinc, arsenic and molybdenum from a small lake in the claim area. Follow-up geological mapping, performed in the same year, identified areas of epithermal silicification with anomalous gold and silver values, which were staked as the Wolf claims. In 1983, geochemical rock and soil sampling was conducted over three silicified areas by Rio Algom Explorations.
In 1984, Rio Algom conducted additional soil and rock sampling, geological mapping and claims staking to cover new discoveries of epithermal silicification in the area. This work included the digging and blasting of eight trenches (52.2 metres) on the Ridge zone. The following year an additional five hand trenches and six diamond-drill holes (593.5 metres) were completed on the Ridge zone. In 1986, the holdings of Rio Algom were acquired by Lornex Mining Corporation and the property was optioned from Lornex by Lucero Resource Corporation, later that same year.
In 1987 and 1988, Lucero Resources conducted an extensive exploration program consisting of road construction, detailed sampling and 1800 metres of backhoe trenching on the Ridge and Pond zones. This work identified a wide zone of low-grade mineralization, which in trench 88-10 returned 2.69 grams per tonne gold and 14.0 grams per tonne silver over 26.5 metres (Property File Rimfire Dawson, J.M., 1990).
By 1990, Lucero Resources had identified the Pond zone, an area of extensive silicification covering 250 metres by 80 metres. Thirty-one chips samples taken, for a true width of 50 metres, across the Pond zone returned an average grade of 0.51 gram per tonne gold (Property File Rimfire Heberlein, D., 1991). Other areas of intense silicification were identified but not sampled; these included the Grid 2, Lookout and Chopper Pad zones.
In 1991, Minnova optioned the property from Lucero Resources and the next year biogeochemistry, airborne magnetic and EM surveys and diamond drilling (2002 metres) were completed on the Ridge zone. A large number of photos were also taken in 1992 of the Wolf area. The majority of these were on the Ridge zone, showing surface exposures, trenches and diamond-drill cores with a brief description of lithology (Property File Rimfire, 1992).
In 1992, Metall Mining Corporation (previously Minnova Inc.)did extensive trenching, gradient array IP, geological mapping and biogeochemical sampling over the Ridge and Pond Zones. This was followed by a fifteen hole, 2002 metres diamond drilling program that discovered a shallowly west-dipping mineralized zone, which outcrops as the Ridge Zone. The program was designed to test zones of strong silicification and epithermal-style gold mineralization exposed in trenches at the Ridge Zone and areas of anomalously high resistivity located about 1,000 metres west of the Ridge Zone.
In 1993, Metall did further trenching, IP, mapping and biogeochemical sampling.
In 1994, Metall continued to extend the area of biogeochemical sampling to the east and southwest, collecting 954 samples. Nine diamond drill holes, totaling 1333 metres were completed. In general drilling resulted in little to no significant veining and no significant gold values. One hole resulted in low grade gold mineralization in quartz breccia veining (Assessment Report 23548). The 1994 biogeochem survey of the Southwest area on the Wolf property did not found any new areas of interest. Discrepancies between the 1992 and 1993 surveys in the Central Area indicated a lack of precision and their trustworthiness and therefore their usefulness was put into question.