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Mouse Mountain

Documents

Mouse Mountain NI 43-101 Technical Report [PDF | 9.2MB].
Bedrock Geology and Mineral Potential [PDF | 5.6MB].

Location

Quesnel, the city, is immediately west of the project area. Prince George, Quesnel and local smaller centers provide experienced manpower, equipment, logistical support and services. Prince George, 120 km north of Quesnel is a major regional center, with regularly scheduled air services to Vancouver and Kamloops. Helicopters and small fixed wing aircraft are readily available for charter.


Aerial view looking east over Fraser River and Quesnel to Mouse Mountain. Note the low rolling hills which make up the Interior Plateau. The higher mountains on the horizon are in Barkerville Terrane.


Mouse Mountain drilling

Mouse Mountain Drill Holes:

Deposit Type

Mouse Mountain, one of the two main targets in the western project area, is considered an alkalic porphyry copper-gold occurrence. Mouse Mountain is immediately next to, or above, small, high level, subvolcanic, magnetic, alkalic, quartz-poor, intrusive bodies that invade Nicola volcanic rocks. This setting closely resembles that of alkalic porphyry copper-gold-PGE deposits found in the Quesnel Trough in central BC. The following description of the deposit type is taken from Panteleyev (1995) and from his description of deposit type L03 in www.mapplace.ca.

The deposits consist of stockworks, veinlets and disseminations of pyrite, chalcopyrite, bornite and magnetite occur in large zones of economically bulkmineable mineralization in or adjoining porphyritic intrusions of diorite to syenite composition. The mineralization is spatially, temporally and genetically associated with hydrothermal alteration of the intrusive bodies and host rocks.

They occur in orogenic belts at convergent plate boundaries, commonly oceanic volcanic island arcs overlying oceanic crust. Chemically distinct magmatism with alkalic intrusions varying in composition from gabbro, diorite and monzonite to nepheline syenite intrusions and coeval shoshonitic volcanic rocks, takes place at certain times in segments of some island arcs. The magmas are introduced along the axis of the arc or in cross-arc structures that coincide with deep-seated faults. The alkalic magmas appear to form where there is slow subduction in steeply dipping tectonically thickened lithospheric slabs, possibly when polarity reversals (or 'flips')
take place in the subduction zones. In British Columbia all known deposits are found in Quesnellia and Stikinia terranes.

The environment of deposition is in high level (epizonal) stock emplacement levels in magmatic arcs, commonly oceanic volcanic island arcs with alkalic (shoshonitic) basic flows to intermediate and felsic pyroclastic rocks. Commonly the high-level stocks and related dikes intrude their coeval and cogenetic volcanic piles. Deposits in the Canadian Cordillera are restricted to the Late Triassic/Early Jurassic (215-180 Ma) with seemingly two clusters around 205-200 and ~ 185 Ma. In southwest Pacific island arcs, deposits are Tertiary to Quaternary in age.

Intrusions range from fine through coarse-grained, equigranular to coarsely porphyritic and, locally, pegmatitic high-level stocks and dike complexes. Commonly there is multiple emplacement of successive intrusive phases and a wide variety of breccias. Compositions range from (alkalic) gabbro to syenite. The syenitic rocks vary from silica- undersaturated to saturated compositions. The most undersaturated nepheline normative rocks contain modal nepheline and, more commonly, pseudoleucite. The silica-undersaturated suites are referred to as nepheline alkalic whereas rocks with silica near-saturation, or slight silica over saturation, are termed quartz alkalic (Lang et al., 1993). Coeval volcanic rocks are basic to intermediate alkalic varieties of the high-K basalt and shoshonite series and rarely phonolites. Deposit boundaries are generally determined by economic factors that outline ore zones within larger areas of low-grade, laterally zoned mineralization.

Deposit boundaries are generally determined by economic factors that outline ore zones within larger areas of low-grade, laterally zoned mineralization.

The principal ore minerals are chalcopyrite, pyrite and magnetite. Bornite, chalcocite and rarely galena, sphalerite, tellurides, tetrahderite, gold and silver are subordinate. Pyrite is less abundant than chalcopyrite in ore zones.

Alteration minerals include biotite, K-feldspar, sericite, anhydrite/gypsum, magnetite, hematite, actinolite, chlorite, epidote and carbonate. Some alkalic systems contain abundant garnet including the Ti-rich andradite variety - melanite, diopside, plagioclase, scapolite, prehnite, pseudoleucite and apatite; rare barite, fluorite, sodalite, rutile and late-stage quartz. Central and early formed potassic zones, with Kfeldspar and generally abundant secondary biotite and anhydrite, commonly coincide with ore. These rocks can contain zones with relatively high-temperature calcsilicate minerals diopside and garnet. Outward there can be flanking zones in basic volcanic rocks with abundant biotite that grades into extensive, marginal propylitic zones. The older alteration assemblages can be overprinted by phyllic sericite-pyrite and, less commonly, sericite-clay-carbonate-pyrite alteration. In some deposits, generally at depth in silica-saturated types, there can be either extensive or local central zones of sodic alteration containing characteristic albite with epidote, pyrite, diopside, actinolite and rarer scapolite and prehnite.

The main ore controls are igneous contacts between intrusive phases and with wallrocks, cupolas and the uppermost, bifurcating parts of stocks, dike swarms and volcanic vents. Breccias, mainly early formed intrusive and hydrothermal types are an important ore control. Zones of most intensely developed fracturing give rise to oregrade vein stockworks.

Porphyry deposits are subdivided on arbitrary economic criteria, mainly ratios between Cu, Au and Mo. Differences in composition between the host rock alkalic and calcalkalic intrusions and subtle, but significant, differences in alteration mineralogy and zoning patterns provide fundamental geologically based contrasts between deposit model types.

Mineralization

The Mouse Mountain Property is a well developed target area with excellent data reporting on a long work history. The property has four known mineral occurrences spread along a 1500 meter long, north northwest trending zone on the northeast side of Mouse Mountain (Figure 14). The most significant prospect, the Valentine Zone, was drilled with 14 percussion holes by Bethlehem Copper in 1970. Quesnel Mines Ltd. stripped a part of the prospect in 1987 and sampled trenches. Teck Corporation completed the most substantive work at Mouse Mountain immediately after this. They focused on targets developed by Quesnel Mines, Placer Dome and others. Their work includes diamond drilling the "high grade" and Valentine zones and other targets and extensive ground geophysical work on three grids.


Mouse Mountain known mineral showings define a 1.5 km long mineralized corridor along the northeast flank of Mouse Mountain. The locations of the Teck geophysical grids (North 1991, South 1991 and Beaver 1991) and the Placer Dome 1989 geophysical and soil geochemical grid are outlined in blue. The topographic contour interval is 20 m and the UTM grid interval is 1 km. Barkerville highway (26) runs east through the middle of the map view.
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