MEG Calgary April Luncheon
Thursday, April 5, 2012 from 11:30 AM to 1:00 PM (MDT)
The 3Ace Propery is located in southeastern Yukon at the confluence of the Hyland and Little Hyland rivers. The region is underlain by sedimentary rocks of the Hyland Group, the basal formations of the Late Precambrian to Late Devonian Selwyn Basin. The geology of the property is comprised of interbedded quartz pebble conglomerates, coarse-grained arkosic sandstone, and black phyllite of the Yusezyu Formation. North of the primary exploration targets the geology is characterised by calcareous sandstones, limestone breccia, and turbiditic limestone and siltstone successions which form a newly recognized formation that occurs between the Yusezyu and Narchilla formations.
Three distinct phases of deformation have been identified on the 3Ace Property, which are distinguished by the orientation patterns of successive fold generations and associated faults. The regional nature of the fold systems suggest that the structures resulted from Mesozoic-age orogenesis along the Ancient North American Craton. Regional mapping during the 2011 field season indicates the fold and fault systems developed progressively to accommodate displacement on the March and Hyland Valley faults, a regional scale trans-extensional dextral fault system. The 3Ace Property lies within a first-order step-over between these two faults and the gold mineralisation occurs along third- or fourth-order oblique-slip to normal faults that formed to accommodate extension within the step-over. Polyphase quartz veins are developed within these fault zones, indicating a prolonged movement history that creates complex overprinting relationships. The final phases of movement on the fault system is brittle and many of the earlier fault zone and associated vein systems are strongly brecciated.
The Main Zone is the highlight of the 3Ace Property consisting of voluminous quartz veining in a brittle fault, extensive hydrothermal alteration, and numerous bonanza grade Au occurrences. The zone has a strike length of approximately 225m and extends down dip for a distance of 225m. The alteration system consists of quartz-carbonate veins, iron carbonate, local silicification, zones of desilicification, and argillic clay. Groundwater penetration has generated extensive limonite from oxidation of the sulphides that overprints the primary hydrothermal alteration package. Mineralisation consists primarily of native Au, arsenopyrite, and pyrite. Minor amounts of sphalerite, galena, and molybdenite have been observed in the core too. Preliminary fluid inclusion work on the quartz veins indicate the hydrothermal fluids had a temperature of approximately 310o, a mesozonal crustal level, and that extensive phase separation occurred during the development of the crack-seal quartz veins. The characteristics of the Main Zone are consistent with structurally controlled, sandstone hosted mesozonal Au-vein systems, which are commonly interpreted to be orogenic gold deposits. Although further research is being completed to confirm this deposit model at the 3Ace Property, it is a new deposit type for the Yukon segment of the northern Cordillera. The recognition of orogenic gold systems at several Au occurrences in this part of Yukon represents a new and exciting opportunity to develop a new Au-district in this underexplored region of Canada.
Chris graduated with a B.Sc. from the University of Waterloo in southern Ontario in 1996. His mineral exploration career began in northern Saskatchewan exploring for unconformity-related uranium deposits for Cameco Corporation. Over a four year period he explored around the Rabbit Lake/Eagle Point deposits, the Wheeler River Project, the Virgin River Shear Zone area, and on historical exploration projects along the north rim of the Athabasca Basin. In 2001 he began a Masters degree at Memorial University, studying under the supervision of Dr. Tom Calon. His thesis described the complex structural architecture and deformation history of the sedimentary and mafic volcanic rocks exposed around the base of the Blow Me Down Ophiolite Massif within the Humber Arm Allochthon. Upon completion of his M.Sc. Chris started a Ph.d. studying the structural controls of Au-bearing meso- and epizonal quartz vein systems hosted by metasedimentary rocks of the Gander Zone, Central Newfoundland. The on-going research project is focused on the tectono-metamorphic history of the Gander Zone and the sequential development of high-strain zones which demarcate prominent ‘steep’ and ‘flat’ belts in the northern Gander Zone. In the course of working on this research project he consulted on several orogenic-style Au-bearing quartz vein systems in Central Newfoundland. In this time period Chris was also involved in mapping and regional structural analysis of uranium deposits and prospects in the Proterozoic-aged Central Mineral Belt of Labrador, including the Michelin and Jacques Lake deposits. Since 2010 Chris has been involved with the 3Ace Property in southeastern Yukon. He joined Northern Tiger Resources Ltd. fulltime in July, 2011 and is currently responsible for managing the 3Ace Property. Chris brings his experience working on structurally complex quartz vein systems in Newfoundland to assist in understanding the structural controls on the property geology and Au mineralisation in the region.
When & Where
The Calgary Mineral Exploration Group Society is a non-profit association incorporated under the Societies Act of Alberta.
The mandate of the Calgary MEG is to foster a recognition of the importance of mineral exploration and the development of mineral resources to the province of Alberta.