Lake Abitibi West Gold Property Moody
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LAKE ABITIBI WEST GOLD PROPERTY Moody Township, Larder Lake Mining Division RECEIVED JAN 2 5 ZOlZ GEOSCIENCE ASSESSMENT OFFICE Timmins, Ontario R.J. Bradshaw, P.Eng. September, 2011 Geologist CONTENTS Page INTRODUCTION 3 LOCATION AND ACCESS 3 PREVIOUS WORK 3 FORMATION OF A GOLD DEPOSIT IN THE ABITIBI 4 SEARCHING FOR A GOLD DEPOSIT 6 INTERPRETATION OF STRUCTURAL GEOLOGY 6 RECOMMENDATIONS AND CONCLUSIONS 8 REFERENCES 9 APPENDIX 1 10 CERTIFICATION 2 A Portion of Map P3398 Geological Compilation of the Lake Abitibi Area Scale o :z 4 " 13/t.m Displays Trace of Arejay Fault interpreted from airborne geophysical surveys (2004) and map P3398; Gold deposits adjacent to faulting and Moody Township property INTRODUCTION To follow is a summary description ofthe process involved in the formation of a gold deposit. Based on the process, mineralogy and structure of the typical lode gold deposit, the most efficient and cost effective exploration procedure is described. Interpretation of airborne magnetic maps over favourable geological terrane is the primary tool. Utilizing the latest airborne magnetic maps, the writer interpreted the structural geology of a substantial area between Matheson and the Quebec boundary, part of the Abitibi Greenstone Belt. Thereafter, the results were compared with published geological maps. Upon finding an untested area demonstrating high potential for gold mineralization, previous work in the immediate area was reviewed in the search for support for the choice. The essential research and interpretation is shown on the attached Figures. Finally, ground acquisition was commissioned. LOCATJON AND ACCESS Moody Township is located a few kilometres west of Lake Abitibi in northeastern Ontario. Two claims, 4254581 and 4254668, held by the writer, in the centre ofMoody Township, form the property which consists of24 sixteen hectare units (960 acres). The so-called Trans Quebec road starts at Iroquois Falls. To access the property, drive south 18 kilometres on an old haulage road from the 54 km marker on the Trans Quebec road. PREVIOUS WORK Across central Moody Township at least 40 diamond drill holes and 20 overburden holes have been drilled over the past 40 years. Initially, companies such as Inco and Texas Gulf formulated programs in the search for base metals. Later, Utah Mines Ltd, Glen Auden Resources and others were focused on the search for gold. Presumably, with a glacio fluvial direction trending northwest, parallel to the Arejay fault, the Moody belt of favourable rocks was considered to be a likely source for the gold bearing glacial float to the southeast. East of the property, mainly south of Traill Lake, Utah Mines Ltd conducted the most ambitious program including ground geophysics, overburden drilling and some 30 diamond drill holes. South ofTraill Lake, drill holes intersected strongly altered rocks containing mariposite fuchsite, which in the Kirkland Lake camp is associated with gold mineralization. These holes are not plotted on the plan. It is reported that up to 3 grams of gold was intersected in the drilling. 3 Within the property, Glen Auden Resources and Mistango River Mines drilled at least five holes. As indicated on the plan these holes are well outside the areas considered to be favourable for gold mineralization. The positioning of the Arejay fault, interpreted from the airborne magnetics, is supported by an intersection of graphitic argillite in Glen Auden hole 91-4. Similarly, a hole by Utah just south of Traill Lake intersected intensely altered serpentinized peridotite, thereby confirming the thrust fault extending west across the property area. In 1988, Glen Auden commissioned an airborne electromagnetic and magnetic survey by Questor. This survey covers the favourable belt of rocks striking across central Moody Township and the property. A well defined faulted conductor coincides with the interpreted thrust fault through the property and over to Trailllake. Most of the conductors within the survey area were interpreted by the geophysicists to dip north. Similarly, the latest government survey, which this report is based on, indicates that the assemblage dips north. Nevertheless, almost all of the drill holes were drilled north. FORMA TTON OF A GOLD DEPOSIT* TN THE ABTTTBT The model to follow is based on the writer's 50 years experience in production and exploration. Understanding the model is essential to the cost efficient search for a viable gold deposit, particularly in the Abitibi Greenstone Belt, where the overburden is deep and extensive. The model should be considered as a general concept that explains the formation of most but not necessarily all gold mineralized zones. It provides a critical path in the planuing of grassroots and secondary exploration. The dominant force in the formation of major and minor structures, including gold deposit structures in the Abitibi, is a near horizontal compression in a north - south direction. This force is a cyclical one taking place over tens of millions of years and is complicated by depth of rock assemblage and extreme temperature variation. Subsequent to the development of isoclinal folding and easterly trending deep-seated thrust faults along the boundaries of major rock assemblages, continued periodic compressive force results in the formation of cross faults and ultimately structures controlling the gold mineralization which vary in complexity. It should be noted that even using laboratory dating techniques, the concept of time involved with these processes is difficult to comprehend. Evidence for a period of formation, amounting to tens of millions of years, include observation of differing generations of mineral deposition, reflected by quartz - carbonate vein ladder structures, etc. As indicated by comparatively minor disruption of the typical gold deposit, perhaps some cross faulting, the gold deposition takes place near the end of the overall deformation process. 4 In many instances the initial stage in the process is one wherein the incompetent potential host rock undergoes a preparatory process. Hydrothermal gases-solutions are injected into a low pressure trap and permeate the adjoining super hot adjoining rock. On cooling the rock is carbonatized, forming a competent unit which with subsequent stress, fractures. This same process may also account for the conversion of magnetite, if present, into pyrite and other iron bearing sulphides. Thus the host rock of the yet to be formed gold deposit becomes an anomalous magnetic low. Carbonatization is not necessary or involved for competent host rocks, which include a variety of felsic to intermediate intrusives. The next and subsequent cycles of compression and heat generation results in fracture and fault openings, followed by the introduction of various mineral components. In many deposits there is evidence for several cycles of mineral introduction followed by one or two fmal pulses wherein the gold and accessory, dominantly sulphide minerals, are introduced. These sulphides which may include pyrite, chalcopyrite, sphalerite and arsenopyrite are intimately associated with gold which may form a solid solution with some sulphides. In many deposits, particularly lode type, it is observed that most of the gold and sulphides is present within less than a metre of deposit contact. The central portion of the lode, over several metres, composed of quartz, carbonate, and tourmaline, etc. contains much less gold. Also, at the deposit contact, the gold is often associated with an alteration mineral such as sericite or fuchsite, a derivative of various feldspars. The various structures hosting the gold deposition are situated adjacent to major deep seated easterly trending breaks which form buttresses for the north-south compression. The gold deposition may occur north or south of the easterly trending breaks, but for whatever reason, more and better mineralized zones are situated north of the known major breaks. The major breaks do not host gold deposits but it is evident because of their proximity to the deposit that portions of the faults have formed conduits for the cyclical hydrothermal injection. The fmal compressive force accounts for the disruption of the deposits. Underground mapping reveals much more faulting than in the two dimensional surface exposure. Faults may trend northeast, northwest and occasionally north and are quite predictable. • A deposit which has the potential to form a mine 5 SEARCHING FOR A GOLD DEPOSIT Few gold deposits display mineralogical characteristics that allow them to be directly detected by geophysical methods. Fewer than one often gold mineralized zones contain sufficient sulphides that would allow them to be detected by electromagnetic or even induced polarization survey methods. Nevertheless, such techniques are commonly used. In several instances electromagnetic surveys led indirectly to the discovery of important deposits because the conductors represent an easterly trending thrust fault adjacent to a mineralized zone. Similarly, geochemical surveys, wherein surface soil samples are analyzed for pathfmder metals or gold, have provided only minimal assistance in finding targets. Considering the major influence of glaciation in the Abitibi, such is understandable. Some form of the airborne magnetic vertical gradient survey is the basic exploration tool. These surveys are more accurate than a ground survey and the tightly constrained magnetic features, representing rock units, enable a very good interpretation of the structural geology. Undertaken