GEOLOGICAL REPORT OF PLATEAU METALS LIMITED'S CLAIMS ADAMS PLATEAU,CHASE,B.C S-alJJ STANLEY J; PEDLEY WORK SUPERVISED BY DR. C.

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1 GEOLOGICAL REPORT OF PLATEAU METALS LIMITED'S CLAIMS ADAMS PLATEAU,CHASE,B.C S-alJJ STANLEY J; PEDLEY WORK SUPERVISED BY DR. C. RILEY April 1, to November 21,1951. y,7 /yip E

2 , IhQEx Summary 1 Introduction Topography Claim Geology Sedimentary Rocks 3 Metamorphic Rocks 4 Volcanics Gneiss Intrusive Rocks Structures 7 Mineralization 9 Correlation of Geology & Geophysics 10,,y ( Geological ffp ork Map 1 In Envelope.

3 ACKNOWLEDGEMENTS: Thanks are rendered to Dr. H.C. Gunning, Department of Geology, who prepared and examined the thin sections used in this report. Appreciation Is also felt toward Dr. C. Riley, P. Eng., who supervised all phases of the mapping, and to Keith A. Mckdams who helped with the latter part of the field mapping.

4 GEOLOGICAL REPORT PLATEAU METALS LIMITED 1951 L L The properties of Plateau Me&.'as are underlain by a series of sedimentary and volcanic rocks which have been highly metamorphosed. These are cut by basic and acid north-south dykes and north-south faults. Along this zone of weakness, copper, zinc, snd lead mineralization is widespread. Folds, favourable replacement horizon, dyke dams and shear or fissure zones are the localizers of this mineralization. Geophysical methods were successful In finding these horizons. INTRODUCTION The Plateau Metals property is located north of Chase, B.C., on the Adams Plateau. The plateau lies north of Shuswap Lake between the Adams Lake and Scotch Creek Valleys. Access to the property is along a rough, good-weather, dirt road. During the summer of 1951, geological mapping was carried on, together with geophysical mapping, road building, stripping with bulldozers and diamond drilling. Mapping was based on the chain and compass lines which were laid out for the geophysical survey at 400' intervals. The main base lines on this grid were surveyed by transit. Happing beyond the limits of the geophysical lines was carried on with pace and compass traverses.

5 - 2 - TOPOGHAPKY The center of the old Adams Plateau peneplalned surface is deeply cut by the south flowing Nikwikwaia. Creek. The west fork of this creek runs through the center of Plateau Metals holdings. To the east of this creek, in the limits of the claims, the land is relatively flat and is cut by several small parallel creeks. To the west it rises unevenly but steadily to a point 800 above the creek. This height of land forms a ridge running northeasterly along the limits of the property. It has an elevation of approximately 6,000. Alpine meadows amid scattered evergreens cover the higher slopes. Lower in the creek valleys on the central and eastern parts of the claims, a balsam and spruce forest predominates. Windfall is moderate and there is heavy undergrowth close by the creeks. Good outcrops occur on the high western ridge. The remaining land is blanketed with overburden. This cover consists largely of residual soils five to twenty feet deep. Local stream and glacial deposits also occur. In this area outcrops are mostly found in the creek bottoms and cutbanks. CLAIM GEOLOGY The rocks within the property have all undergone a high degree of regional metamorphism. Bedding planes, schistosity planes and composition bands show consistant strikes to the northeast with dips averaging 200 to the northwest.

6 - 3 - In the western area, where the characteristics of the rocks were not completely masked, a series of limestones, limey argillites and quartsites were mapped. Underneath these lie a horizon of chlorite schists with local amphibole rich horizons near the contacts of basic intrusives, Beneath the schists there is a series of volcanic rocks which in turn were underlain by a gneiss. SEDIbENTARY ROCKS The younger rocks, those which outcrop on the west of the property, show sufficient evidence to classify them as having a sedimentary origin. In turn they can be divided as follows: Arsillltes These light green to grey rocks form low broken ridges. They have a moderate lime content and often show l/8 inch to l/4 inch bedding bands. Lenses of quartsite and limestones are contained within them. Ouartzites These form highly resistant ridges. Edany fissure veins of quartz are present, The outcrops show some bedding but are commonly massive. Limestone% Low, slumped outcrops of light green to grey coloured limestone are found between the argillites and quartzites. They contain fine recrystallized seams of calcite and otherwise closely resemble the argillite. Some horizons are coarsely crystalline and are a true marble. A second black limestone is also present. It is

7 - 4 - characterized by bands up to l/2 inches thick of cream- weathering recrystallized calcite. MEXAMORPHIC ROCKS Underlying the sediments is a horizon of metamorphic rocks whose origin is unknown. These are predominately chlorite schists. This rock is banded with green chlorite and white calcite showing a schistose to gneissic structure. commonly it contains pyrite or magnetite crystals up to l/4 : An alteration phase near certain basic dykes was mapped as an amphibole chlorite schist. A microscopic examination of three thin sections was made -- one of the chlorite schists, one of an inter- mediate contact phase and one of the amphibole bearing rock. The summary of the descriptions is as follows: 1. Chlorite Schist or Gneiss - much biotite and chlorite - lo; : quartz - Feldspar - sodic plagioclase - less than the quartz - much calcite - abundant epidote - a few cubes of pyrite - streaks of spots of a clay product(leucoxene?)

8 Schistose phase of Amphibole Clorlte Schist. A granulated rock with gneissic foliation highly recrystallized. - Feldspar probably sodic plagioclase - Little or no quartz - Chlorite - green residual of some amphibole - Epidote and much fine gralned epidote - Leucoxene - some titanite gone over to leucoxene 3. Amphibole Chlorite Schist. - 35,i greenish to buff amphibole - 35% epidote and clinozoisite (secondar minerals T s fresh feldspar - plagioclase close to oligoclase - Calcite intergranular to other minerals and replacing amphibole - Chlorite a few nests and intergrowths - possibly metamorphosed from an igneous rock. VOLCANICS A series of volcanic rocks underlie the schists. These are mostly massive, dark, fine to medium grained traps with a few thin felsite bands. The upper section shows one or two bands of white crystalline marble interbedded with the volcanics. The outcrops are massive and their attitude is not determinable.

9 - 6 - GNEISS In the southeast corner there outcrops a highly siliceous gneiss. 131s d=rk reddish rock is composed of pink feldspars and white quartz with some dark minerals. The composition bands are regular and strike and dip parallel to the sedimentary formations. A fine grained rock resembling the gneiss was mapped across the northern claims of the property as quartsite. Here the highly altered country rock contains large amounts of introduced quartz ivhich mask their original nature completely. However, it differs from the gneiss in thattfie bands are highly contorted and folded and are generally light to dark green in colour, MICROSCOPE A thin section of this rock is summarized thus: Fine grained swirled and folded it shows much granular quarts. Much chlorite after a green amphibole. Much epidote and soisite. Some feldspar 1 to 2$ Intergrowth with quartz mosaic. This may be an altered sedimentary rock, JNTRUSIVE ROCKS The oldest intrusive rocks are a series of fine to medium grained black dykes. These contained small radiolites of a green amphibole and commonly contained amygdules of calcite.

10 - 7 - The dykes occur singly and in swarms. They have steep dips and most strike north-south although a few strike coast-west. These basic rocks weather quickly to a green sand. These intrusives were relatively fresh, showing little refracturing and no metamorphic alterations. Contacts are characterized by the development of amphibole ml.nerals. Magnetite, pyrrhotite, chalcopyrite and pyrite are commonly found replacing the nearby country rock and filling small shears and drag folds. The youngest intrusive is a fresh white fine to medium grained,sometimes porphyritic, rhyolite. This rock consists of quarts and feldspar with very minor pyrite, No ferro-magnesium minerals are present. These intrusions are dyke like in form wlth uneven contacts. They also follow a north south trend. The nearby country rock Is saturated with quartz and minor pyrite. These acid rocks form high resistant ridges wherever they occur. A contact with the basic dykes show xenoliths of this rock within the rhyolite indicating the latter is the younger of the two. STRUCTURES Folding Most attitudes taken revealed a consistant northeasterly strike of the rocks with a shallow southwest dip. However, local gentle folds up to 100 feet wide were observed. Many small dra:; folds under a foot in amplitude were also seen.

11 * 8 - Faulting Two large faults were mapped. One along the West Fork Creek and one along Shmoo Creek. Numerous isolated gouge and breccia zones indicate the presence of others. 'However, the limited number of outcrops prevents the construction of a fuller picture. These fal:lts follow the north-south trend of the country. The fault zone is characterized by local breccias often vuggy, with quantities both crystalline and microcrystalline quartz. Pyrite is common and at Shmoo Creek a coarsely crystalling green fluorite is abundant. Gouge bands are found up to five feet in width. Topographically the fault zones are represented by creek valleys. Bdinor fractures are common over all the property. They usually have less than a foot displacement and are commonly perpendicular to the schistose or bedding planes. Graphite commonly forms along the slips in the sediment white chlorite and sericite forms along the slips in the schists. )UNERAI,IZATION On the present Plateau Metals' holdings,the first encouraging find was made by prospectors in It consisted of a few large boulders carrying rich chalcopyrite replacement. These suggested that nearby there was a mineralized zone which could be over four feet thick. Further promise was given by a geophysical survey in the spring of 1951 which showed a number of anomalies existed in this area.

12 - 9 - Bulldozer stripping and diamond drilling was carried on later In the year to further explore this zone. Bulldozing supplied much valuable information which was later confirmed by diamond drilling. This can be summarized as followsr Sulphide mineralization is widespread across the property. Several loci of mineralization are recognized, 1. Favourable beds - Horizons favourable to replacement 2. Damming - The basic dykes occasionally acted as dams to the circulating mineralizing fluids leaving the "favourable beds" on one side of them richly replaced. 3. Folds - The shallow folds concentrated mineralization at the apex of the anticlines. This is also true in the case of smaller drag folds. 4. Slips and fractures of ten contained fine seams of chalcopyrite and pyrite. 5. Contact replacement - particularly true on the contacts of some basic dykes. Any one or combination of the first four of these is considered as favourable prospecting locations. The mineralization is predominately pyrite and chalcopyrite. Pyrhotite, sphalerite and magnetite are common and galena, molybdenite and hematite are also present, The deposition of the minerals favoured the chlorite schist horizons but interesting deposits are also present in the lavas and quartzites.

13 CORRELATIOI: OF GEOLOGY AND GEOPHYSICS k geophysical E.U. Survey was conducted on the property early in the spring by XcPhar Geophysics Ltd. The anomalies mapped on the survey and later explored in detail were found to correlate with certain geological horizons. These were as follows: 1. On the west of the property within the sediments the anomalies fell close to well defined graphite bearing shear zone. 2. Within the chlorite schists they followed mineral bearing favourable horizons or series of horizons. 3. On the east of the property one anomaly apparently followea a mineralized shear zone.

14 COSTS OF GEOLOGICAL SURWZ - PLATiZAU MET.&LS LIMITED SEMOi? OF 1951 S.J. haleg S.A.Sc. Geologist July Aug.1.31 SepLl $15.00 $ K.A.McAdam Dr.C.Rilsy Asst.Geologlst.Aug.l9- Sept $9.00 $ Consultant July 22. Sept $ $ c. Riley. Ihc;;ber 27,1951.

GEOLOGY OF THE NICOLA GROUP BETWEEN MISSEZULA LAKE AND ALLISON LAKE

GEOLOGY OF THE NICOLA GROUP BETWEEN MISSEZULA LAKE AND ALLISON LAKE (92H/15E. 10E1 By V. A. Preto INTRODUCTION Mapping was continued southward from the area covered in 1973 and an additional 55 square