Mishi Lake Gold Property Mishibishu Lake Area, Wawa

Transcription

1 Mishi Lake Gold Property Mishibishu Lake Area, Wawa Location, Accessibility, Infrastructure and Local Resources The property is located 40 km west of Wawa, Ontario, in the Mishibishu Lake Area, Sault Ste. Marie Mining Division, District of Algoma, Ontario. The property is accessible by vehicle from Highway 17 North, 50 km north of Wawa, then west 50 km along the Paint lake Road to the Mishi Mine and Mill complex, then east along Mishibishu East Road for 8 km where old tractor roads lead south-east through the heart of the claim block. A power transmission line parallels the Paint Lake road along its entire length. The community of Wawa is the nearest source of manpower, supplies and services to logging, mining and exploration industries. Wawa is easily accessed and provides rail, ship, road and air transportation facilities. Location Map, Mishi Lake Property, Mishibishu Lake Area 1

2 Land Tenure The Mishi Lake Gold Project is comprised of 3 mineral claims; one is in the Mishibishu Lake Area and two are in St. Germain Township covering 656 hectares (32 Units) located on the eastern central portion of the Mishibishu Deformation Zone in the Mishibishu Lake Greenstone Belt. The Mishi Lake Gold Project is located 10 kilometres east of Wesdome s open pit Mishi Mine and 5 kilometres east of the past producing Magnacon Gold Mine. The mineral rights are held by Argo Gold Inc. of Toronto, Ontario. In addition to the acquired claims, Argo Gold staked two small claims in the Mishi Lake Area adjacent to the acquired claims. The two additional claims have been staked to cover open portions of the Mishibushu Deformation Zone. The newly acquired claims and staked claims are adjacent and east of the Wesdome Lease which contain several historical gold prospects (Discovery, Hollinger, Amichi, Northwest Prospects). Recent and Historical Exploration Land Tenure, Mishi Lake Property, Argo Gold Inc. The Mishibishu area has seen sporadic exploration since the early 1900s through to about 1935 when high grade gold was discovered north of Mishibishu Lake. In 1937 Hollinger Consolidated Mines, Macassa Mines and Erie Canadian Mines carried out prospecting, stripping, trenching and diamond drilling on their properties. Parts of the Erie Canadian claims covered the subject property. Erie Canadian noted shearing and quartz veining. Beginning in 1983, MacMillan Energy and the MacMillan/Granges Joint Venture conducted numerous exploration programs including airborne surveys, line cutting, prospecting, soil geochemistry, geology and diamond drilling on their large property holdings, which included the Mishi Lake Property. Recent exploration on the property from consisted of airborne geophysics, line cutting, stripping and sampling. The Magnacon Gold Deposit and the Mishi Gold Mine are both located on strike to the west of the Mishi Lake Property along the Mishibishu Deformation Zone. Several gold 2

3 prospects west of the Mishi Lake Property contained significant gold grades on surface and in diamond drill core. These gold prospects are spatially close to the metavolcanic metasedimentary contact in zones of ductile deformation. Geology, Structure, and Mineralization The Mishi Lake Property is underlain by mafic metavolcanics and metasedimentary rocks of the Mishibishu Lake Greenstone Belt. The rocks have been regionally metamorphosed to greenschist facies increasing to amphibolite grade locally where in contact with external granitoids. In the Mishi Lake area these rocks have been intruded by the Mishibishu Lake monzonite stock. Sills and dikes of the monzonite stock intrusde the metavolcanics and metasediments. A series of NNE and WNW diabase dikes intrude all the rock types. Regional Geology, Mishi Lake Property, Mishibishu Greenstone Belt The Mishi Lake area forms part of the east-central portion of the Mishinishu Deformation Zone (MDZ). The Mishibishu Deformation Zone is the largest of the deformation zones in the belt, measuring approximately 40 km in length and several hundred metres up to 1.5 km in width. The MDZ is located north of the Mishibishu Lake Stock and straddles the lithological contact between mafic metavolcanics to the north (hanging wall) with clastic metasediments to the south (footwall). The MDZ has received most of the detailed geological mapping (Millard 1984, Glover 1986 and Heather 1985, 1986) because it hosts the majority of gold showings in the belt. The highest degree of strain intensity and alteration within the Mishibishu Lake belt is found in the east central section of the MDZ. Shear zones are broad and exhibit pervasive deformation and alteration. Mafic metavolcanics in the hanging wall become progressively more strained and altered with increasing proximity to the centre of the 3

4 zone. Conglomerate clasts are attenuated and only the most competent clasts (i.e. granitoid and ironstone) are discernable from matrix. An intense penetrative foliation strikes approximately 300 o and a well developed stretching lineation plunges moderately to the north and northeast. Asymmetric Z- and S-folds, as well as rare M folds, plunge to the east and less commonly to the west. Chevron folds, crenulations and kink bands add to the complexity of the structure (Source: OFR 5774). Local Geology, Mishi Lake Property, Mishibishu Lake Area The central core of the MDZ is characterized by intense hydrothermal alteration which in conjunction with the deformation serves to obliterate much of the primary rock textures. The inner 250 m of the MDZ contains schists made up of variable amounts and combinations of chlorite, sericite, ankerite, quartz, calcite, green mica, feldspar and pyrite. Gold mineralization occurs both in foliation-parallel quartz veins which are commonly boudinaged and strongly deformed, crosscutting the foliation and commonly occupying axial traces of kink bands, and late quartz ± tourmaline veinlets, which have various orientations. The quartz veins are contained within highly sheared rocks consisting of chlorite-sericite ± ankerite ± calcite ± pyrite ± quartz schist (Source: Dicovery Prospect OFR 5774). Detailed Geology Mishi North Gold Occurrence (after Tremblay, 2010) The Mishi North Occurrence is located near the southwest corner of claim A stripped area 70 metres in length and 20 metres wide exposes mafic metavolcanics and highly sheared and altered mafic metavolcanics consisting of quartz-sericite-ankerite+/- green mica+/- pyrite schist. Small sections of metasediments (meta-argillite) and felsic metavocanics (meta-tuff) occur with the mafic metavolcanics. 4

5 Quartz veins occur as foliation-parallel and are highly deformed (boudinaged and Z- folded) in the southern half of the exposed outcrop. In the northern portion of the outcrop a larger quartz vein, 20 m by 1 m, trends northwest and is bounded by an alteration zone of quartz-sericite-ankerite+/- green mica+/- pyrite schist. Late shear zones cut across the rocks with NE and NW strike. A grab sample from the NW quartz vein returned 75 g/t Au and 0.06 g/t Au in the altered wall rocks. A grab sample taken from the metasediments (pyritic meta argillite) retuned g/t Au. Detailed Geology, Mishi North Gold Occurrence Summary and Conclusions The main area of interest are the claims immediately east of the Wesdome Lease. These claims are underlain by the east-central portion of the Mishibishu Deformation Zone which is estimated by the Ontario Geological Survey to be approximately 1.5 km in width through the Mishi Lake Property. The main gold prospect on the property is the Mishi North Gold Occurrence which is located on the ESE trend of several gold prospects, including the Discovery, Hollinger, Amichi, and Northwest. All these gold prospects have the characteristic of occurring in 5

6 quartz veins within highly deformed and altered metavolcanic and metasedimentary rocks near the metavolcanic-metasedimentary contact. The spatial association between gold mineralization and felsic intrusions has been recognized across the Superior Province of Ontario (Colvine et al. 1988). The Mishibishu Lake Stock is a high-level, late-to post tectonic intrusive body of quartz monzonite to monzonite composition which intrudes the southern part of the Mishi Lake Property. Intrusive quartz-feldspar and feldspar porphyry dikes related to the Mishibishu Lake Stock are common in the vicinity of several of the gold occurrences within the MDZ, including the Mishi Lake Property There appear to be similarities between the Discovery Prospect which is located NW of the Mishi North Occurrence and is characterized by a NW trending quartz vein enclosed by an alteration envelope composed of chlorite-sericite ± ankerite ± calcite ± pyrite ± quartz schist. Some of the higher gold grades in grab samples by the Ontario Geological Survey ranged from 13 to 82 g/t Au. The two easternmost claims are not contiguous with the main Mishi Lake claims. Recent exploration by Kitrinor Metals Inc. in 2012 consisted of prospecting and a soil geochemical survey (MMI). Two of the soil samples from the Argo Claims have the highest gold response ratios of the survey: 164 and 28 Au Response Ratio (samples and ). Recommendations The stripped area for the Mishi North Gold Occurrence should be mapped in detail by a structural geologist. Additional grab samples should be taken at regular intervals throughout the altered zone. Channel sample need to be taken across the main NW trending quartz vein, including the adjacent altered wall rock. A series of channel samples should be taken along the strike of the quartz vein to determine grade continuity. The deformed quartz veins in the southern part of the stripped area should be channel sampled, including the altered wallrock. An orientation survey using complete digestion and partial extraction methods for soil samples (i.e. MMI and regular analysis) should be completed across the strike extension of the NW vein at closely spaced intervals (i.e. 5 m) to determine how responsive these methods are to gold mineralization. A similar soil geochemical orientation survey should be completed at the southeast extension of the stripped area. Prospecting and sampling over the main Mishi Lake claims with special focus in the area around the Mishi North Occurrence. Several drill holes were located near the Mishi North Gold Occurrence; one drill collar was found north of the occurrence which is thought to be Granges DDH M-166. Drill hole M-166 intersected 4.2 g/t Au over 1 metre near surface and may reflect the near surface gold occurrence. Three additional holes were 6

7 drilled to follow-up the results from M-166, but the collars have not been identified; the drill holes intersected anomalous gold values in altered schist. The contact area between the Mishibishu Lake Stock and adjacent rocks should be prospected for signs of shearing and quartz veining. The OGS mapped porphyritic sills on the property which may be associated with gold mineralization. Knowledge Gaps Many of the gold deposits and prospect in the Mishibishu Deformation Zone straddle the the metavolcanic-metasedimentary contact. How much is the exploration potential of the Mishi Lake Property limited because the metavolcanic-metasedimentaty contact extends south of the shore line of Mishi Lake? Intrusive quartz-feldspar and feldspar porphyry dikes related to the Mishibishu Lake Stock are common in the vicinity of several of the gold occurrences within the MDZ. How significant is the presence of these dikes and the monzonite stock on the location of gold occurrences? Has the late period of quartz vein development affected the Mishibishu Lake Stock or related dikes and sills? A significant amount of trenching, drilling, sampling is present within the Wesdome Lease area, but drops dramatically along the strike extension onto crown land. Is the paucity of drill holes and trenching due to a lack of mineral exploration or is there some geological reason? The Mishibishu Deformation Zone is characterized by high degree of ductile strain, including the development of mylonites. There appear to be two main styles of goldbearing quartz veins: early highly deformed quartz veins sub-parallel to the shear fabric, and later quartz veins at a high angle to the shear fabric. Altered rocks within the shear zones do not carry a high gold content. Does the lack of major, continuous vein systems limit the economic viability of the MDZ to low grade, high tonnage deposits (i.e. Mishi Deposit)? Is there any felsic or mafic intrusions within the tectono-stratigraphc package that may provide a ductility contrast which could result in brittle fracture and provide a plumbing system for gold-bearing hydrothermal fluids? 7

8 Photographs on the Mishi North Occurrence Geology Map (after Tremblay 2010) Photo 1: Quartz Vein is Z-folded on centimetre scale Photo 2: Quartz-sericite-ankerite+/- green mica-+/- pyrite Photo 3: Boudinaged and Z-folded Quartz vein on the metre scale 8