The Pinguicula Group is a Proterozoic succession of clastic and carbonate rocks exposed in the Wernecke Mountains of northern Yukon. The strata were deposited with angular unconformity on the Wernecke Supergroup following the Racklan orogeny and emplacement of the Hart River sills. Two contact relationships have been resolved in the 2009 field season. The first, a 1.38 Ga dike previously thought to crosscut unit A, has instead been recognized to crosscut the underlying Wernecke Supergroup strata. This relationship is significant because it once again places the lower age limit of the Pinguicula Group into question and may reposition the Pinguicula Group within the history of geologic events. Secondly, the previously undefined contact relationship between units B and C has been identified as a gradational contact confirming the placement of unit C within the Pinguicula Group. In addition, preliminary data collected from the western Ogilvie Mountains draws similarities between units PR1 and PR2 of the lower Fifteenmile Group and units A, B and C of the Pinguicula Group. Although preliminary results from the 2009 field season have resolved some of the unknowns surrounding the Pinguicula Group, they have also raised more questions.

The study area is underlain by four stratigraphic successions ranging in age from Middle Proterozoic to Early Paleozoic. From oldest to youngest, they are: Middle Proterozoic Wernecke Supergroup; Middle to Upper Proterozoic Pinguicula Group; Upper Proterozoic Windermere Supergroup; and Uppermost Proterozoic to Lower Paleozoic sandstone and carbonate. Together, they represent about a billion years of intermittent sedimentation punctuated by processes such as deformation, uplift, erosion, magmatism and mineralization. Rocks in the study area record eight phases of contractional and extensional deformation, some of which may be related to strike-slip faulting. Two phases of southwest-verging folds and thrust faults may be related to dextral transpression on the Snake River Fault. Mineral enrichments occur in two general forms:: breccia-related (Middle Proterozoic), and veins (Mesozoic to Tertiary). The breccia-related occurrences have enrichments of Cu ± U, Co, Au and Ag, as dissemminations and veinlets in and near intrusive breccia zones (Wernecke breccia). The vein occurrences comprise Zn-Pb-Ag ± Cu and Au, in veins and related lenses and irregular replacements of carbonate.

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The Rackla River area is underlain by normal faulted and gently folded sedimentary strata of the Paleoproterozoic Wernecke Supergroup, Mesoproterozoic Pinguicula Group, Neoproterozoic Hematite Creek Group and Windermere Supergroup, and Paleozoic Bouvette Formation. Gabbro dikes and sills that are likely age equivalent to the ca. 1380 Ma Hart River Sills cut the Wernecke Supergroup rocks. The presence of a mafic volcaniclastic horizon within the Bouvette allows its informal subdivision into a lower and upper member. These volcaniclastic rocks may the distal equivalent to volcanic rocks near the Tiger deposit, located ~20 km to the southwest. Three major angular unconformities are documented in the map area: at the base of the Rapitan Group, the base of the lower Bouvette, and the base of the upper Bouvette Formation.

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Paleozoic rocks of the Pelly Mountains, central Yukon, preserve greater than 150 m.y. of sedimentation, magmatism and base-metal mineralization. To identify secular trends in regional tectonics and metallogeny, a multi-year project on the stratigraphy of the Pelly Mountains in the Quiet Lake (105F) and Finlayson Lake (105G) map areas was initiated. Field studies during summer 2015 focused on two stratigraphic intervals: (1) mafic volcanic, volcaniclastic and clastic rock successions assigned to the Cambrian-Ordovician Cloutier and Groundhog formations (Kechika group); and (2) felsic volcanic, volcaniclastic and clastic rock successions assigned to the Devonian-Mississippian Black Slate and Felsic Volcanic formations (Seagull group). Cambrian-Ordovician strata were deposited in a marine environment characterized by episodic mafic volcanism and extensional tectonism. Devonian-Mississippian strata record the transition from an extensional turbidite basin to a metalliferous volcanic rift basin, and resemble key rock assemblages of the Selwyn basin (Earn Group) and Yukon-Tanana terrane (Grass Lakes and Wolverine Lake groups).

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Granodiorite of the Coast Plutonic Complex intruded metasedimentary rocks in the Dezadeash Range of the northern Coast Belt in the late Mesozoic. Graphitic staurolite-biotite schist, associated with the Kluane Metamorphic Assemblage, underlies the western Dezadeash Range, whereas cordierite-biotite gneiss, previously correlated with the Late Proterozoic - Paleozoic Nisling Assemblage, is exposed in the eastern and southern regions. A terrane boundary was placed in the central Dezadeash Range. Recent petrographic studies reveal a southeastward increase in metamorphic grade. Prograde appearance of cordierite partly obliterated an older schistosity and caused a fabric change near the postulated terrane boundary. Furthermore, typical continental margin rocks, such as marble and quartzite, are not observed. This suggests that all metamorphic rocks in the Dezadeash Range can be correlated with the Kluane Metamorphic Assemblage, whereas Nisling Assemblage rocks occur in the Coast Mountains to the east. Therefore, the terrane boundary is located in the Dezadeash River valley, further southeast than previously thought.