Geol of Part of Strathy Cassels
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3iM04sw0a92 2.2545 STRATHY 010 GEOLOGY Of part of STRATHY-CASSELS GROUP (Manderstrom-Niemetz-Morrison Option) District of Nipissing, Ontario Hollinger Mines Limited Timmins, Ontario filed for assessment November 24, 1977 P. J. Bateman l A - i - SUMMARY The property is composed of five unpatented mining claims in south-central Strathy Township, Sudbury Mining Division. It lies within the northeast part of the Temagami metavolcanic belt - a ©window 1 of Keewatin rocks surrounded by Huronian sediments of the Southern Province. The claim- group is underlain by a layered sequence of mafic, intermediate, and felsic metavolcanic rocks up to 4500 feet (1350 metres) thick. The sequence is intruded by a roughly linear ©sill 1 of diorite, which has, in turn, been injected by porphyry. Late stage intrusion is represented by west-north-west-trending olivine diabase dykes. The metavolcanic assemblage is on the north limb of the Lake Tetapaga Syncline, and appears to have been anticlinally cross-folded about a northwest axis in the north part of the group. West-north-west faulting was superimposed on the fold structures, followed by northeast faulting, and east-north-east shearing. Several small sulphide showings were found in the felsic volcanic rocks, and one returned significant assays in Cu, Ag and Au. However, these showings appear to be confined to narrow north-north-east tension fractures complimentary to regional shear zones. It is recommended to complete the geophysical surveys, examine more samples geochemically and petrographically, evaluate the results, and compare with maps of adjacent ground by D,R. Alexander. Any encouragement should be followed up by drilling. LOCATION of CLAIM GROUP ( PART of MAN DERSTROM- MORRISON- NIEMETZ OPTION J STRATHY TWP., DISTRICT of NIPISSING SCALE: l" z O-S mile* or 0-8 km. (1cm. opprox. equols 3IOm.) - l - INTRODUCTION This report is intended as a presentation of geological survey results from part of the Strathy-Cassels claim group, as completed by the writer from September 19 to 23, 1977. The map-area is part of a larger group being com piled by D.R. Alexander. Basic geological information is interpreted in combination with the regional mapping of previous workers, aeromagnetic and ground magnetic trends, and available assessment data. Funding for this project is provided under a joint venture agreement between Hollinger Mines Limited/ Box 320, Timmins, and St. Joseph Explorations Limited, 90 Eglinton Avenue West, Toronto. PROPERTY, DESCRIPTION and LOCATION The group consists of 5 unpatented mining claims, S-398943 to S-398947 inclusive (Figure 1), located in the south-central part of Strathy Township, Sudbury Mining Division. All the claims have been optioned from Mr. Wm. Manderstrom, Box 429, Temagami, Ontario, Mr. H. Niemetz, Box 252, Temagami, Ontario, and Mr, Wm. F. Morrison, 2219 Kennedy Road, Agincourt, Ontario. The centre of the claim-group is about 2 miles (3.2 km) north and east of Temagami Townsite. The Sherman minesite is approximately 2 miles (3.2 km) further west. - 2 - ACCESSIBILITY, CLIMATE and TOPOGRAPHY The central part of the claim-group is traversed by the paved Milne-Sherman highway. This road heads west from Highway #11 at a point 1.1 miles (1.8 km) north of Temagami. A spur of the Ontario Northland Railway also crosses the property, enroute to the Sherman Mine. Several large lakes in the area are amenable to access by float plane. ,The property is partly covered by the sand-plain forming the north shore of Link Lake. Lakeshores, creeks, and flooded areas are swampy. Elevations range from about 1000 feet (300 metres) to 1050 feet (315 metres) above mean sea level. The average July temperature is 18.8OC. (66OF.) and the January temperature averages -12.8OC. (9OF.). Mean annual precipitation is 32 in. (81.3 cm) with rainfall on an average of 170 days per year. HISTORY Showings of Fe, Au and Ni-Cu were prospected in the area as early as the 1890©s. The first geological map was produced by A.E. Barlow of the G.S,C. in 1907. Subsequent government mapping included that of W.W. Moorhouse in 1942, and G. Bennett and D.G. Innes in 1971. The present claim-group was part of the former Maralgo Mines property extending from Totem Lake to within 2 claim lengths of the Cassels Township boundary. Their ground was covered by geological and ground magnetic surveys prior to an AQ diamond drilling program in 1956. Two holes were drilled on each side of Highway #11, but the main area of interest centred east of the highway and north of Johnny Creek on mineralized altered felsic volcanic breccia. Sulphides with associated arsenopyrite occur in local subsidiary shears north of the main shear zone, and were tested by 13 drill-holes totalling 4923 feet (1477 metres) Cu and Zn values were generally low and Au values erratic. The - 3 - best results were D.56% Cu, D.07% Zn and 3.63 oz. Ag/ton from 230 feet (69 m.) to 245 feet (73.5 m.) in Hole #7, and Q.22% Cu, S.57% Zn, and 1.40 02. Ag/ton from 335 feet (100.5 m.) to 345 feet (103.5 m.) in Hole #8. The Maralgo drill zone straddling Highway #11 was further probed by Wm. Morrison with a drill-hole in 1970. Stadacona Rouyn Mines Limited drilled carbonatized, sheared, felsic metavolcanics from a collar southwest of the intersection of Highway #11 and the Milne-Sherman Highway in 1950. The ground adjacent to the west of the present map-area was explored in 1975 by Metalline Resources Inc. (now Gambit Cons. Explors. Ltd.). Ground magnetic, VLF, E.M., and geological surveys were completed, followed by four AQ diamond drill-holes totalling 1206 feet (362 metres). Quartz carbonate veins with minor pyrite and pyrrhotite, and fracture-breccia sections, yielded only trace values in Au. Hollinger optioned the Strathy-Cassels * group in early 1977 after a preliminary examination. A grid was cut, and that part which qovers the subject of this report totals 4.3 miles (6.9 km), consisting of cut lines spaced 400 feet (120 metres) apart off an ENE baseline. REGIONAL GEOLOGY General The Temagami metavolcanic belt is a relatively small remnant (maximum of 16 by 20 miles, 25 by 32 km) of Keewatin ©basement 1 . Together with adjacent granitic plutons, they form a ©window 1 of Superior-type rocks surrounded by Huronian strata in the Cobalt plain of the Southern province (Card et al, 1972). Strathy Township is underlain by the northeastern part of the - 4 - belt, and is about 15 miles (24 km) north of the Grenville Front. © The ©greenstone© belt consists of a layered meta- volcanic sequence which ranges in composition from basalt to rhyolite, and is overlain by metasediments. The combined thickness of metavolcanics in Strathy Township (entire north limb of Lake Tetapaga Syncline) may total as much as 20,000 feet (6000 metres); however, parts of the sequence may be repeated or truncated by one or more of several regional faults. The oldest rocks exposed are fine- to medium-grained basalts and andesites, which vary from massive and structureless, to pillowed, vesicular, amygdaloidal, or variolitic. Flow units range from 300 feet (90 m.) to 5000 feet (1500 m.) thick. There are also a few exposures of purplish andesite with chloritic clots and occasional small yellowish leucoxene grains. Basic agglomerate and breccia are relatively abundant, being either massive and undeformed, or sheared with lenticular fragments. Dacitic flows or tuffs overlie the basic metavolcanics along with intermediate volcanic breccias. These are succeeded upward in the section by rhyolite flows and tuffs. Acid flow units are from 300 feet (90 metres) to 3000 feet (900 metres) thick, and are particularly abundant around Vermilion and Link Lakes. The felsic tuffs are usually altered and sheared. Quartz porphyry is abundant in the area and intimately associated with the felsic metavolcanics, probably as subvolcanic intrusives. The top of the section, or of each major volcanic cycle, consists of metasediments and/or iron formation. The metasedimentary units are from 200 feet (60 metres) to 1000 feet (300 metres) thick, and are composed of laminated slate and greywacke with or without volcanogenic tuffs. The oxide facies iron formation is made up of alternate bands of massive magnetite, sugary white quartzite, jasper, grey cherty quartz, and/or treraolite-chlorite tuff. Units of banded iron formation range from a few feet (l to 2 metres) to more than 500 feet (150 metres) thick. - 5 - The layered sequence is intruded by 300 foot (100 m.) to 700 foot (210 m.) thick sills of medium-grained, white- weathering, quartz diorite. These rocks are similar to the coarse thicker parts of basic flows, but are thought to be partly intrusive, and possibly mafic feeders. The main sill along the Northeast Arm (Portage Bay) of Lake Temagami may even be differentiated, as the north part is very siliceous with local aplite dykes. The south contact of this dyke is marked by chlorite schist and speckled with yellowish flecks of leucoxene. South of Kanichee Lake on the old Cuniptau property, the metavolcanics are intruded by an oval stock of gabbro with minor peridotite and diorite (the Ajax Intrusion - Bennett, 1975). The ultramafic phase appears to be altered to a mixture of fibrous hornblende and serpentine. Northeastern Strathy Township is principally underlain by the Chambers-Strathy granitic ©batholith 1 composed of coarse massive pink quartz monzonite with marginal finer-grained sheared i grey trondhjemite. Diorite and quartz diorite are also found as hybrid phases bordering granitic plutons. Both intrusive and extrusive rocks appear to have been regionally metamorphosed to greenschist facies grade. Altered diabase and a few lamprophyre dykes intrude the complex along north and west-northwest trends.