The Bull 4 showing is located about 90 kilometres south of Burns Lake on the north shore of Chelaslie Arm.
The region in which the showing occurs is within the Intermontane Belt, underlain dominantly by Lower to Middle Jurassic volcanic and sedimentary rocks of the Nechako Formation, Hazelton Group consisting the Nechako and Naglico Formations. These assemblages are overlain by the Upper Cretaceous to Lower Tertiary Ootsa Lake Group and Miocene plateau basalt. Intruding the Hazelton Group is a belt of granodiorite, diorite and quartz diorite plutons of the Late Cretaceous Chelaslie River-Tetachuck Lake Plutonic Suite and Eocene feldspar porphyry.
The Bull claims are underlain by Lower to Middle Jurassic Hazelton Group rhyolitic and andesitic volcanics with minor epiclastic sediments. These are intruded by Eocene Ootsa Lake Group rhyolite dikes which are in turn cut by diabase dikes. A quartz vein stockwork and breccia zone, hosted in mafic tuff and breccia, contains up to 5 per cent pyrite, 3 per cent galena and 1 per cent sphalerite. The veining is exposed over a strike length of 20 metres and the width of the zone is between 2 and 4 metres. The vein system is open along strike to the west but to the east mineralization appears to be cut off by rhyolite dikes. There appears to be at least 2 vein structures striking east-west with near vertical dips.
The best sample was a grab sample taken across 30 centimetres of a quartz vein stockwork with 1 per cent galena and 5 per cent pyrite which assayed 2.1 grams per tonne gold, 22 grams per tonne silver and 0.273 per cent lead (Assessment Report 22535, sample #463762).
Work History
Placer Developments Ltd. staked their MR claims in an area later covered by the Bull 1 claim, and reconnaissance mapping and sampling were carried out in 1973. A total of 196 soil samples were taken. Two well-defined, moderate-intensity, lead-zinc soil anomalies were recognized by Placer in areas underlain by oxidized quartz-feldspar porphyry and rhyolitic rocks. The larger anomaly, with peak values of 173 parts per million lead and 780 parts per million zinc, covered an area of 400 by 800 metres and remained open to the northeast.
In 1980, Prism Resources staked their Precious Metal claims to cover Placer's MR lead-zinc anomaly. They conducted reconnaissance geological mapping and sampling that year, taking a total of 218 soil, silt, and rock samples. This work defined a 600 by 700 metre lead-zinc soil geochemical anomaly with maximum values of 1950 parts per million lead and 2760 parts per million zinc (Assessment Report 22535). Silver values were erratic and generally low. In 1982 the pulps were reanalysed. Gold and molybdenum values were generally low in both soils and rocks. Higher arsenic values were obtained in soils, to a maximum of 145 parts per million, coincided with the previously defined lead-zinc anomaly.
In 1992, Sleeping Gold Ltd. carried out a preliminary exploration program on the Bull property, consisting of geological mapping, prospecting, and soil sampling. This program was designed to verify the reported lead-zinc-arsenic soil anomalies, locate their source. A total of 24 rock samples and 152 soil samples were taken.
In 2007, a helicopter-borne geophysical survey was carried out on behalf of Golden Dragon Explorations Inc. on the South Claims project (Assessment Report 29485). The survey extended along the northeast side of Chelaslie Arm from Euchu Lake (Reach) northwest to end of Chelaslie Arm and about 8 kilometres north from the northwest end of the arm. The length of the area survey from northwest to southeast was about 27 kilometres and from 5 to 6 kilometres across from northeast to southwest. The survey covered MINFILE showings Bull 4 (093F 063) at the southeast end of the survey, the MT (093F 031) in the central part of the survey and the Chelaslie Arm (093F 025) towards the northwest end of the survey. The northwestern part of grid is reported to be very active in terms of electromagnetic anomalies; the central part is subdued in electromagnetic activity; and fewer anomalies exist in the southeastern area. Magnetic anomalies are due to either magnetic intrusions or magnetic rich volcanics except in the southeast portion where there are more linear trends, possibly reflecting dikes or magnetic and non-magnetic flows.
In 2015, John Kreft completed a program of prospecting and geochemical (rock and soil sampling) on the area. A representative grab sample (BBUR-08) from a 10-centimetre wide quartz-pyrite-galena vein assayed 0.375 per cent lead, 14.6 grams per tonne gold and 71.3 grams per tonne silver (Assessment Report 35554).