The Hart River area (maps 116 A/10 and 11) of the southeastern Ogilvie Mountains is underlain by two varied and widespread successions which offer the most potential for discovery of sediment-hosted base metal deposits in the northern Canadian Cordillera. A 'shelf sequence', north of the Dawson fault, includes:: Middle Proterozoic Wernecke Supergroup; Middle and (?) Late Proterozoic Fifteenmile group; the Late Proterozoic Windermere Supergroup; Ordovician and Silurian carbonate; Ordovician to Devonian (?) Road River Group; Devonian Ogilvie Formation; and Devono-Mississippian Earn Group. The 'offshelf sequence' includes:: Late Proterozoic Hyland Group; Cambrian volcanic rocks; Lower Cambrian Vampire Formation equivalent; Cambrian Gull Lake Formation equivalent; Cambro-Ordovicain Rabbitkettle Formation equivalent; Ordovician and younger(?) Road River Group; Mississippian Keno Hill quartzite; and Devonian(?) to Jurassic(?) Lower Schist. The most promising exploration targets are:: 1) massive sulphide deposits associated with the Hart River volcanic rocks in the Gillespie Lake Group (upper part of the Wernecke Supergroup); 2) sedimentary copper deposits in the Fifteenmile Group; 3) 'Anvil-type' pyritic massive sulphide deposits in the transition zone between the Gull Lake and Rabbitkettle Formations; 4) 'Howard's Pass-type' zinc-lead deposits in previously unmapped black shales and chert of the Road River Group; 5) sulphide deposits associated with Cambrian, Ordovician(?) and Devonian(?) mafic volcanic and intrusive rocks; 6) covered areas at the base of the Lower Schist which may overlie the Earn Group, with potential for 'Macmillan Pass-type' zinc, lead, silver, barite deposits; 7) volcanogenic massive sulphide deposits associated with felsic volcanic rocks in the Keno Hill quartzite.

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Mineralized zones on the Jason property are stratifrom, sediment hosed Pb-Zn-barite deposits that occur in a Late Devonian age marine carbonaceous shale and turbidite sequence. The Jason Property is located 400 km northeast of Whitehorse near Macmillan Pass on the Canol Road. Since the discovery of mineralization in 1975, eighty-nine diamond drill holes have delineated three mineral deposits. In order of their discovery, they are known as the Main, South and End zones. Geological reserves indicated and inferred for the three zones total 14.1 million tonnes averaging 7.1% Pb, 6.6% Zn and 79.9 g/t Ag. The following questions are the focus of the study:: 1) What is the stratigraphic position and setting of the South zone? 2) What is the geological relationship of the South zone to the Main zone? 3) What is the geometry of the South zone? 4) How can the mineralization in the South zone be described in terms of mineralogical and textural facies? 5) What constraints on the processes of ore formation can be demonstrated by utilizing the above studies?

Recent field investigations have improved our knowledge of the Quaternary surficial geology, stratigraphy and glacial limits in the McQuesten map area. This information has important applications to surficial geochemical and placer exploration. The Quaternary geology of this area is unique because it encompasses early to middle Pleistocene (pre-Reid) glacial surfaces that are preserved beyond the limit of the Illinoian (Reid) glacial limit. These pre-Reid surfaces have been exposed to long periods of weathering and erosion, which have diminished their original distribution and expression. Stratigraphic exposures examined in the map area provide new evidence for a large glacial lake(s) in the Lake Creek basin (‘glacial lake Coldspring’); the lake developed when pre-Reid ice dammed outlets in the Willow Hills and lower Lake Creek. In addition, there is evidence that another large glacial lake (‘glacial lake Rosebud’) formed on the west side of the White Mountains when a pre-Reid glacier dammed Rosebud Creek. Fieldwork in the White Mountains and on Australia Mountain allowed us to delineate the pre-Reid glacial limit at approximately 1000 m (3300-3400 ft) a.s.l. This elevation is lower than the pre-Reid glacial limit previously mapped for the area by Duk-Rodkin (1999) and is consistent with mapping performed in the adjacent Stewart River map sheet by Bostock (1964), Jackson (2005a,b) and Froese and Jackson (2005).

The Southwest McQuesten-northern Carmacks area is primarily underlain by rocks of the Yukon-Tanana terrane which is divided into two distinct belts separated by the Willow Creek fault: 1) a central belt of polydeformed, upper greenschist-amphibolite facies metasedimentary and metaplutonic rocks of Permian and older ages; and 2) a northeastern belt of generally undeformed and unmetamorphosed volcano-plutonic rocks of the Early Mississippian Reid Lakes complex. The southern part of the area is underlain mainly by rocks of Quesnellia and Stikinia, including: 1) Paleozoic retrogressed metamorphic rocks of the Boswell assemblage; 2) Upper Triassic augite-phyric volcanic rocks; and 3) Early Jurassic granitoids of the Aishihik plutonic suite. These rocks are dissected by a series of dextral strike-slip faults, probably related to the Teslin fault system. Post-accretion rocks include: 1) mid-Cretaceous biotite monzogranite plutons; 2) dacite and minor basalt of the Upper Cretaceous Carmacks Group; and 3) Quaternary basalt of the Selkirk volcanics. The southwest McQuesten-northern Carmacks area is under-explored, but shares many geological attributes with nearby, highly prospective districts such as the Dawson Range mineral belt, the recently discovered White Gold area and the producing Minto Mine.

The past-producing McKay Hill property on NTS map sheet 106D/6 (Nash Creek) has previously been described as polymetallic Ag-Pb-Zn ± Au-style mineralization. During the 2009 YMIP-funded exploration program the central claims on the property were mapped and numerous distinct differences from the proposed polymetallic model became apparent. Unlike Keno Hill, veins on the McKay Hill property lack siderite gangue and are not present as vein-faults. Propylitic alteration halos surrounding vertically zoned ore shoots (high-level Au-Cu and deeper level Ag-Cu-Pb) were observed within consistently north-northwest-striking, near vertical, siliciclastic and hypabyssal-volcanic rocks. The Ag-Pb-Zn veins in the Keno Hill Camp were emplaced in discrete dilational fault structures within polydeformed clastic metasediments and are not associated with extensive alteration. Host rock competency in both areas is vital in controlling mineralization. Re-evaluating the regional framework could potentially illustrate the area’s metallogenic potential for different types of mineral occurrences.

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Mainly schitose clastic strata of the northern Selwyn basin underlie Lansing map area. These strata form rounded mountains, although jagged ridgelines occur in the thermal metamorphic aureoles surrounding six Cretaceous granitic plutons. Major faults occupy some broad northwest-trending valleys: two of these extend eastward as the Hess and Macmillan faults (Abbott and Turner, 1990) in the Macmillan Pass area; another appears to contine westward as the Robert Service Thrust Fault. Argentiferous galena veins were intermittently mined from the east edge of the map area from 1976 to 1985; whereas the stratiform base metal and disseminated gold potential of these rocks have been investigated during the 1990s.

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