ASSESSMENT REPORT GEOLOGICAL, GEOCHEMICAL SURVEY SLAM GROUP ATLIN MINING DIVISION TATSAMENIE LAKE AREA, B. C. OWNER: CHEVRON MINERALS LTD.

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1 ASSESSMENT REPORT GEOLOGICAL, GEOCHEMICAL SURVEY SLAM GROUP ATLIN MINING DIVISION TATSAMENIE LAKE AREA, B. C. N.T.S. 104KlIE + 8E LATITUDE LONGITUDE 58O 14' N ' W OWNER: CHEVRON MINERALS LTD. OPERATOR: CHEVRON CANADA RESOURCES LIMITED Author: Godf rey Wal ton October 1 984

2 TABLE OF CONTENTS Page LOCATION AND ACCESS CLAIM STATUS AND HISTORY REGIONAL GEOLOGY GEOLOGICAL SURVEY STRUCTURE ALTERATION AND MINERALIZATION GEOCHEMICAL SURVEY CONCLUSIONS AND RECOMMENDATIONS REFERENCE COST STATEMENT STATEMENT OF QUALIFICATION APPENDIX A - Geochemical Preparation and Analytical Procedure

3 LIST OF FIGURES (I) Location Map Page 2 (2) Claim Map (3) Grid Location Map 3 5 In Pocket J (4) a. Geological Map b. Geological Map (5) a. DetailedSilicaGeology b. Detailed Silica Geochemistry - Au, Ag c. Detailed Silica Geochemistry - As, Sb, Hg (6) a. Soil Geochemistry - Au b. Soil Geochemistry - Au (7) a. Soil Geochemistry - Ag b. Soil Geochemistry - Ag (8) a. Soil Geochemistry - As b. Soil Geochemistry - As (9) a. Soil Geochemistry - Sb b. Soil Geochemistry - Sb 11 1 I 11 I1 I1 It I I I I 11 I I 11 It

4 LOCATION AND ACCESS The SLAM claim group is located at 'N and 'W approximately 200 km southeast of Atlin, B.C. (Fig. I). Access to the claims was by helicopter from a base camp at Tatsamanie Lake, 25 km north of the claims. The claim group is situated mostly on a broad grassy plateau. The western most area of the SLAM Group extends just below treeline. CLAIM STATUS AND HISTORY The pertinent information on the SLAM group is outlined below (Fig. 2). CLAIM RECORD NUMBER RECORD DATE NUMBER OF UNITS SLAM 2008 September 12, GRAND 2053 September 26, STRIKE 2052 September 26, In 1983 a brief soil geochemical study was completed. No geochemical response was obtained from any of the silica bodies. REGIONAL GEOLOGY The SLAM claims are underlain by Lower or Middle Triassic(?) foliated diorite and pre- Upper Triassic greenstone and phyl l i te (Souther, ). The contact between the intrusive and greenstone-phyl l i te package runs diagonal ly across the claims, southwest to northeast. East and south of the claims lies a large mass of Lower or Middle Triassic(?) diorite while west and north of the claims is an extensive area of pre-upper Triassic greenstone and phyllite. To the north, and to some extent within the SLAM claims, lie Permian limestone.

5 \ \ 8 - GROUP I LOCATIOW MAP M Km LOCATION MAP

6 FIGURE 2 SLAM GROUP CLAIM MAP

7 GEOLOGICAL SURVEY Approximately 85 man days were spent mapping the SLAM claims. The geochem- geophysics grid was used for mapping at a scale of 1:2500. The location of the grid with respect to the claim boundaries is shown on Figure 3. According to Souther (1 971) the SLAM Group is situated on Permian limestone, pre- Upper Triassic greenstone and phyllite and Lower or Middle Triassic foliated diorite. Detailed geological mapping has indicated the presence of Cretaceous and Tertiary Sloko Group rhyolites, possibly Jurassic(?) gabbro and diorite-quartz diorite and intensely silicified Permian limestone. Geological exposure on the claims is relatively poor but detailed mapping has shown structural and geological complexity (Fig. 4a,b). With the information to date various ideas have been suggested but this will be dealt with in a latter section. A detailed map of a "block" of silicified limestone was mapped on a scale of 1 :200. This "block" of silicified limestone is situated at 20+50N, 5+50E Permian: Stikine Limestone (Unit 2) The main occurrence of limestone lies just off the grid to the north of the SLAM claim The limestone is fresh, light to medium grey, we1 l bedded and general ly medium grained. Sti kine limestone also contains minor chert beds while course grained quartz veins up to a few centimeters wide intrude the limestone. There are also minor occurrences of a carbonaceous limestone. The carbonaceous limestone appears fresh, dark grey with a greenish hue, fine grained and thinly bedded. This limestone is moderately we1 l fractured and contains calcite veins up to I cm wide.

8 W 5: 28+00N SLAM ; W Y Moosehorn La&.:'' :,:';:. :.... #' - SLAM GROUP Figure 3 0 I... Km Scale 1:50000 NTS: 104KIE/BE A

9 than the Tertiary felsites, quartz-feldspar porphyries and rhyolites, This dioritequartz diori te phase of intrusive may be related to gabbroic-dioritic intrusions cropping out on the edges of the plateau around the west central and southern areas of the grid. Tertiary? Polymictic Breccia (Unit 7) The polymictic breccia unit contacts the older foliated diorite unit to the east and crops out between 8+00N 7+00E and 3+50N 5+00E though extends south of 2+00N 4+00E. Though this unit may be 100 m wide(?) its long, linear shape and abundant slickensided fracture surfaces suggest the possibility of a faul t breccia origin. Clay alteration and local silicification suggest the presence of hydrothermal activity as we1 I. The breccia contains clay altered fragments (possibly Sloko rhyolite?) and limonitic (clay) altered fragments (possibly diorite?). Trace pyrite and greenish fuchsi ticlooking fragments are present as well. Fragments are angular to rounded and generally matrix supported. Chalcedony veins occur irregularly within the polymictic breccia. The matrix is dark grey to black, possibly siliceous and possibly mil led? Moderate to strong silicification of the polymictic breccia occurs from 3+50N, 5+50E to 5+00N, 6+00E. Tertiary (Cret) Sloko Group: Purple Rhyolite (Unit 7) This rhyolite is fresh containing a fine grained, purple groundmass, with up to 10% feldspar phenocrysts. The feldspar phenocrysts are 1-2 mm long and lightly to intensely clay altered. The purple rhyolite also contains trace quartz eyes and black biotite-looking phenocrysts generally less than I mm. Limonitic stains are confined to fractures.

10 these greenstones are on the flanks of the plateau on NE, west central and southern areas of the grid. In the northeast area of the grid lie mostly mafic phyl litic tuffs and foliated tuffs. These tuffs are fresh, fine to medium grained, often laminated and dark green. The southern area of the grid also contains mafic phyl litic tuffs but mainly felsic phyl lite crops out. The felsic phyllite is well fractured and foliated, buff coloured and has a sandstone-like texture; possibly this phyllite originally was a sandstone or volcanic sandstone(?). The felsic phyl li te is intruded by many irregular, buffcreamy to black chalcedony veins. Fine grained, fresh, dark grey to black phyl litic siltstones occur sporadically throughout the property. Lower or Middle Triassic(?) Diorite + Limonitic Diorite (Unit 5) Medium to coarse grained, fresh, foliated diorite occurs in eastern areas of the grid. The diorite is weakly chloritized and often magnetic. South of O+OON to about!+son on the baseline is a 20 m wide zone of rusty, limonitic diorite, in contact with Sloko rhyolite on its west side. In this rusty limonitic zone magnetite has been destroyed. Between 3+50N 5+50E to 5+50N 6+50E is an intensely clay-limonite altered zone of diorite. In this area the diorite contains a stockwork of buff-creamy chalcedony and jasper veins. Some jasper veins may be up to 0.5 km wide. The intrusive texture is still apparent in some clay-limonite altered diorite zones. Jurassic(?) Diori te-quartz Diorite Dykes (Unit 6) Both of these dykes are fresh, fine grained, aligned with each other and are in contact with silicified limestone in the southwest area of the grid. The diorite is a dark grey rock while the quartz diorite is light grey and sugary textured. Both rock types contain sulphides-pyrite up to I% while the diorite also contains pyrrhotite and is very magnetic. The quartz diorite is weakly magnetic. These dykes appear very different

11 Silicified Limestone: (Unit 2s) Most of the limestone on the SLAM Group is silicified though there is also some dolomitization present. The limestone that is silicified is likely of Permian age though the age of silicification is uncertain (see "Alteration and Mineralization"). Silicification is intensely pervasive within the limestone. The silicified limestone is a hard, dense rock, usually light grey with irregular lenses, beds or zones of medium grey to black cherty layers and/or zones of pyrite or carbon. Much of the silicified limestone contains at least a minor amount of limonitic material giving a light orange "stain" throughout. Grain size is general ly fine. Layering or remnant bedding is we1 l preserved in many locations within the silicified limestone. Local areas of brecciation within the silicified limestone is likely depositional. These small zones of brecciation contain angular, rotated silicified limestone fragments. Polymictic quartz breccias occur within silicified limestone containing chert, silica, and rarely what may be siltstone (greenstone?) fragments. The best occurrence of these breccias lies below the cliffs of silicified limestone at 20+50N, 5+50E. Brownish-buff dolomitized limestone of ten contains intense stockwork of quartz veins. Chert beds are also contained within the dolomite as well as trace amounts of pyrite. In many instances layering appears to have been destroyed by dolomitization though in the south part of the grid some dolomite outcrops are layered. Pre-Upper Triassic: Stikine Greenstones (Unit 3 and 4) Most of the claim group consists of Stikine greenstone. The greenstone package con- sists of: mafic foliated and phyllitic tuffs, laminated tuffs, phyllitic sediments, felsic phyl li tes, non-descript greenstone and foliated augi te porphyry. The best exposures of

12 Tertiary (Cret): Sloko Group: Volcanic Breccia (Unit 7) The main occurrence of the volcanic breccia unit is 100 m south of O+OON on the baseline. The volcanic breccia occurrences are likely pipe zones within the Sloko group. The breccias are in a contact with the purple rhyolite and contain purple and grey-buff (clay altered) rhyolite fragments. Fragments are angular to sub-round and up to 20 cm long averaging less than I cm long. The breccias also contain limonitic fragments that may be of dioritic origin. Irregular jasper veins intrude the breccia locally. The matrix is fine grained, dark grey to black. STRUCTURE As mentioned above, though outcrop exposure is relatively poor, geological mapping has indicated structural complexity within the grid area. Aerial photographs suggest both major northerly-southerly and easterly-westerly trending structures. In the northern part of the grid it is likely that the silicified limestone is fault bounded on the west and possibly on the east though the east contact is very difficult to determine. ALTERATION AND MINERALIZATION Most of the limestone within the grid is intensely silicified pervasively. Most of the remainder of limestone has been dolomitized and this often contains a moderate to intense stockwork of quartz veins. The dolomitization of limestone is likely presilicification and perhaps the only way for a dolomite to accept silica is in vein form - hence a stockwork. Silicification is post-permian and likely pre-cretaceous-tertiary though hydrothermal alteration may have continued into the Cretaceous-Tertiary clay altering some of the Sloko group rocks.

13 Moderate to intense silicification of polymictic breccias occur around 3+00N 5+50E to 5+00N 6+00E. Local areas of Sti kine Assemblage greenstone have undergone intense quartz-fe-carbonate alteration. The only significant mineralization is from silicified limestone at 20+00N to 20+50N from S+SOE to 7+50E. This silicified limestone contains irregular dark, brassy blebs and zones of pyrite plus irregular, f ine-grained, medium grey "dustings" of pyrite. It appears that gold anomalies may be associated with the fine grained, medium grey pyrite. A galena vein, not presently in outcrop, within silicified limestone contains greater than 550 g/t silver and 100,000 ppb Hg. Of ten anomalous gold mineralization indicates anomalous values in Ag, As, and Sb. GEOCHEMICAL SURVEY A 2 km north-south baseline from mid GRAND claim to mid SLAM claim was established (Fig. 5-8). At the 2 km north mark the baseline was off-set 850 m east where it continued north for 800 m. Lines ran east and west of the baseline up to I km in each direction. The established grid was also used as a mapping base. Forty-six man days were spent soil sampling samples. Soil samples were collected at 50 m intervals along lines. Lines are spaced 50 m apart except from ION to 14N east of the baseline and between I ON to 20N west of the baseline where line spacing is 100 m. Samples were sent to Chemex Laboratory in North Vancouver. They were prepared and analyzed as outlined in the Appendix A. The samples were typically collected using a soil mattock from 5 to 25 centimeters below the surface and placed in gussetted Kraf t soil bags.

14 Lines traversing east of the baseline were over soils of glacial origin for the most part. Soil development is good in most areas. On the steep flanks of the plateau in the west area of the grid talus fines often had to be collected as no soil was available. Anomalous Au values up to I I0 ppb occur around the north silica area, baseline 20+50N to 22+50N and to the east. A ppb Au in soil is located in the middle of the plateau at 12+00N 5+OOE. Silver values are mostly less than I.O ppm. Antimony values from 15 ppm to 160 ppm occur between 20+00N to 23+50N generally east of the baseline west of the northern silicified limestone cliffs. This area is the "SLAM slump" area where questions have been raised as to whether this is outcrop or not. Arsenic values are generally low ( 30 ppm) throughout the grid though a few high values (up to 620 ppm) occur in the high Sb area. Highly anomalous ( 1000 ppb) Au values in rock have been obtained from silicified limestone containing blebs of the grained, medium grey pyrite. Gold values in the hundreds of ppm occur within silicified limestone containing no visible sulphides - simply silica. High As and Sb values can occur with or without the presence of anomalous gold. High silver (up to 10 ppm) often correlates with Au in silicified limestone though anomalous Ag may also be associated with galena. Note MG-277 contains 550 g/t silver from a galena vein. CONCLUSIONS AND RECOMMENDATIONS (I) Soil geochemistry did not indicate any zones of anomalous Au though spurious anomalies occur throughout the grid. A zone of Sb (minor As) anomalies deline- ated NW, downslope on "SLAM SLUMP", of the main northern silicified limestone cliffs.

15 (2) Hock geochemistry on silicified limestone produced significant gold values. Extensive rock sampling of all the silicified limestone bodies should be carried out and possibly detailed rock sampling to be done on the silicified area of the polymictic breccia. (3) Trenching should be completed in the vicinity of the silicified bodies to locate any high grade values. Detailed geological mapping should be continued outside of the grid and outside of the property. This would enable further assessment of the area immediately surrounding the claims. Also any additional information may aid in the interpretation of the geology.

16 REFERENCES Souther, J. G. ( ), Geology and Mineral Deposits of Tulsequah map-area, British Columbia, Geological Survey of Canada, Memoir 362, 84p.

17 COST STATEMENT SLAM GEOLOGY GEOCHEMISTRY ( I ) Personnel Name Position Field Days Off ice Days G. Walton M. Thicke M. Gray G. Wober W. Hewgi l l M. Woods A. Paramonof f T. Zanger A. Grigoruk Supervisor Geologist Jr. Geologist Sampler Sampler Sampler Sampler Sampler Sampler man 3 off ice (2) Geochemistry Au, Ag, As, Sb Rocks samples I63 1 samples (3) Camp Costs $60/man days x $ I I9/man day (4) Helicopter 25 hours ~$450. (5) Drafting I0 Total

18 STATEMENT OF QUALIFICATIONS I, Godfrey Wal ton, have worked as a geologist since 1974 in Alberta, British Columbia, Yukon, Northwest Territories and Ontario. I graduated in 1974 with a B.Sc. (Hons) degree from the University of Alberta and was awarded a M.Sc degree from Queens University in January have been employed by Chevron on a permanent basis since I am a member in good standing with the Canadian Institute of Mining and Metallurgy, the Society of Exploration Geochemists and the Mineralogical Association of Canada. I supervised and carried out the work on the SLAM claim. 6 J~ GODFREY WALTON

19 APPENDIX A GEOCHEMICAL PREPARATION AND ANALYTICAL PROCEDURES 1. Geochemical sarnples (soils, silts) are dried at 500C for a period of 12 to 24 hours. The dried sample is sieved to -80 mesh fraction through a nylon and stainless steel sieve. Rock geochemical materials are crushed, dried and pulverized to - I00 mesh. 2. A 1.OO gram portion of the sample is weighted into a calibrated test tube. The sample is digested using hot 70% HC 104 and concentrated HNO3. Digestion time = 2 hours. 3. Sample volume is adjusted to 25 mls. using demineralized water. Sample solutions are homogenized and allowed to settle before being analyzed by atomic absorption procedures. 4. Detection limits using Techtron A.A.5 atomic absorption unit. Copper 1 ppm Molybdenum I ppm Zinc I PPm *Silver 0.2 ppm *Lead - I PPm *Nickel I PPm Chromium - 5ppm *AS, Pb & Ni are corrected for background absorption. 5. Elements present in concentrations below the detection limits are reported as one half the detection limit, i.e. Ag - 0. I ppm.

20 PPM Antimony: A 2.0 gm sample digested with conc. HC I in hot water bath. The iron is reduced to Fe +2 state and the Sb complexed with I -. The complex is extracted with TOPO-MIBK and analyzed via A.A. Correcting for background absorption 0.2 ppm Detection limit: 0.2 ppm PPM Arsenic: A I.O gram sample is digested with a mixture of perchloric and nitric acid to strong fumes of perchloric acid. The digested solution is diluted to volume and mixed. An aliquot of the digest is acidified, reduced with K1 and mixed. A portion of the reduced solution is converted to arsine with NaBH4 and the arsenic content determined using f lameless atomic absorption. Detection limit: I ppm PPM Tungsten: 0.50 gm sample is fused with potassium bisulfate and leached with hydrochloric acid. The reduced form of tungsten is complexed with toluene 3,4 dithiol and extracted into an organic phase. The resulting colour is visually compared to similarly prepared standards. Detection limit: 2 ppm W FIRE ASSAY METHOD - Silver & Gold Silver and gold analyses are done by standard fire assay techniques. In the sample preparation stage the screens are checked for metallics which, if present, are assayed separately and calculated into the results obtained from the pulp assay. 0.5 assay ton sub samples are fused in litharge, carbonate and siliceous fluxes. The lead button containing the precious metals is cupelled in a muffle furnace. The combined Ag & Au is weighed on a microbalance, parted, annealed and again weighed as Au. The difference in the two weighings is Ag. F.A. - A.A. GOLD COMBO METHOD For low grade samples and geochemical materials 10 gram samples are fused with the addition of 10 mg of Au-free Ag metal and cupelled. The silver bead is parted with dilute HNO3 and then treated with aqua regia. The salts are dissolved in dilute HC I and analyzed for Au on an atomic absorption spectrophotometer to a detection of 5 PP~.

The Cobalt Rainbow. Airborne geophysical maps show that a north trending aeromagnetic high suggests further undiscovered mineralisation.

The Cobalt Rainbow. Airborne geophysical maps show that a north trending aeromagnetic high suggests further undiscovered mineralisation. The Cobalt Rainbow The property is located on Greenstone Creek, approximately 4.8 kilometres south west of the creek mouth. The property is located about 24 km due west of Campbell River, in the east-central