An evaluation of hydrocarbon resource potential in Eagle Plain is one aspect of the Yukon Sedimentary Basins Project, a five-year (2008-2013), collaborative Geo-Mapping for Energy and Minerals (GEM) Program of the Geological Survey of Canada (GSC), in partnership with the territorial governments and universities. As part of this project, Yukon Geological Survey (YGS) and Northern Cross (Yukon) Limited (NCY) are collaborating with the GSC to assess shale gas potential of Devonian shale at Eagle Plain. Diamond drill core was retrieved from mineral exploration properties to evaluate shale gas potential of Devonian shale of Road River Group and Canol and Imperial formations. Diamond drill core from four holes, located on the Rich property east of Eagle Plain Hotel, were examined and sampled. The core was systematically sampled and analysed by Rock-Eval pyrolysis, optical microscopy, X-ray diffraction (XRD) mineralogy, and palynology. The results indicate that the succession is thermally overmature with respect to hydrocarbon generation. Due to the high levels of thermal maturity, the Rock-Eval data are unreliable. However, high amounts of residual organic carbon suggest that the Canol Formation has the potential to be an important source rock in the region, under favourable burial conditions. The very high level of thermal maturity of the strata also resulted in very few identifiable Palynomorphs; however, Canol and Imperial formation samples yielded dates of Middle to Late Devonian and Frasnian to Famennian, respectively. XRD analyses indicate Canol Formation shale is highly siliceous whereas Road River Group shale and silty shale of the Imperial Formation are less siliceous and exhibit a more varied lithology. This study suggests that the Canol Formation is more prospective for shale gas than strata of the Imperial Formation or Road River Group.

not_specified

The Upper Devonian to Lower Carboniferous Tuttle Formation was an exploration target for oil and gas in the Peel Plateau and Eagle Plain in the 1960s and 1970s. To date, seven minor gas shows have been identified in the Tuttle Formation in the Peel region. This study is part of a long-term project to investigate the sedimentology, stratigraphy and hydrocarbon potential of this unit in the Peel region. The Tuttle Formation forms the upper part of a siliciclastic wedge that was deposited in the foreland basin of the Yukon and Ellesmerian fold belts. In the eastern Richardson Mountains, on Trail and Road rivers, it occurs as alternating packages of resistant and recessive intervals. Resistant intervals, 23 to 54 m thick, comprise five lithofacies including fining-upward sandstone, massive sandstone, siltstone, conglomerate and diamictite. Recessive intervals, 55 and 144 m thick, consist of siltstone and shale and are mostly covered.

Peel Plateau and the contiguous east flank of the Richardson Mountains, northeastern Yukon, comprise a relatively unexplored but prospective petroleum basin. Within the Devonian succession of this basin, shale rocks of unit ‘Cf’ are little known, but may have the potential to form an important conventional source and/or unconventional reservoir target. Unit ‘Cf’ is dominated by thick intervals of dark grey to black, siliceous, organic-rich marine shale, together with intercalated siltstone and very fine grained sandstone beds. Although unit ‘Cf’ has been mapped at surface on the eastern flank of the Richardson Mountains, it is not known whether it occurs to the east in the Peel Plateau and Plain subsurface. A correlation of this unit to the Ford Lake Shale (‘CF’ map unit), which occurs to the west in Eagle Plain and Kandik basins, has been implied. In this study, unit ‘Cf’ was assessed for lithology, mineralogy, age and hydrocarbon source and reservoir rock potential, including type and quantity of organic matter and thermal maturity. Common organic geochemical analytical techniques were utilized (including Rock-Eval pyrolysis and optical microscopy), together with X-ray diffraction (XRD) to determine shale mineralogy and age determination by palynology. Outcrop characteristics were then utilized to identify unit ‘Cf’ in four subsurface Yukon wells: H-37, N-25, I-21 and A-42.

Upper Paleozoic strata in the eastern Richardson Mountains, northern Mackenzie Mountains and Peel Plateau of the Yukon consist of basinal sediments overlain by a siliciclastic sedimentary wedge derived from the Late Devonian Ellesmerian orogeny. Unconformably overlying Paleozoic strata in the Peel Plateau are Cretaceous sedimentary rocks that were deposited in the foreland basin of the Cretaceous Cordilleran orogeny. This study, as part of the interdisciplinary “Regional Geoscience Studies and Petroleum Potential, Peel Plateau and Plain” project, examines the sedimentology, stratigraphy and hydrocarbon potential of Upper Paleozoic strata in the Peel region and adjacent Richardson and Mackenzie mountains. Units investigated as part of this study include the Canol (Upper Devonian), Imperial (Upper Devonian) and Tuttle (Upper Devonian-Lower Carboniferous) formations, ‘Cf’ map unit (?Upper Devonian-Lower Carboniferous), and ‘Mo’ map unit (?Upper Devonian-Lower Carboniferous). Preliminary analyses suggest the Canol, Imperial, Tuttle, ‘Cf’ and ‘Mo’ are potential hydrocarbon source rocks for the region. The Tuttle Formation is the best prospective reservoir rock of the Upper Paleozoic strata.

Whitehorse Trough is a frontier basin in south-central Yukon that is thought to contain gas and possibly oil. It formed in the early Triassic as an arc-marginal basin between the ancient North American margin to the east and the volcano-plutonic Stikine Terrane to the west. Three stratigraphic units, termed the Lewes River Group (Upper Triassic), the Laberge Group (Lower-Middle Jurassic) and the Tantalus Formation (Upper Jurassic-Lower Cretaceous), are recognized in the Whitehorse Trough. The Laberge Group is informally subdivided into four units, which, from the base upwards includes the Richthofen, Conglomerate, Nordenskiold and Tanglefoot formations. The Richthofen formation in the Laberge map area (NTS 105E) is characterized by thin- to mediumbedded turbidites, massive sandstone, matrix- and clast-supported conglomerate, scarce ammonites and belemnites, and abundant trace fossils, particularly Chondrites. No comprehensive stratigraphic section exists for the Richthofen formation, but it is estimated to be at least 500 m thick and appears to consist of a lower clast-supported conglomerate unit, a middle unit dominated by thin- to-medium bedded turbidites with minor amounts of massive sandstone and clast- and matrix-supported conglomerate, and an upper clast-supported conglomerate unit. The Richthofen formation unconformably overlies the Lewes River Group and was deposited by a southeast-prograding submarine fan (or fans) during the Early Jurassic. It is correlative with the Inklin Formation in northwestern British Columbia. Programmed pyrolysis using Rock-Eval 6 analysis of 63 samples from the Richthofen formation indicates that it is a poor to fair source rock and is gas-prone.

Previous studies based on regional geology, sediment type and stratigraphic thickness, concluded that the Bonnet Plume Basin in northeastern Yukon has gas potential, but insignificant oil potential. However, these studies were not based on samples collected from within the basin. For this study, in total, 226 rock samples collected from outcrop and drill core throughout the Bonnet Plume Basin were analyzed by Rock-Eval 6 programmed pyrolysis and combustion to assess the petroleum source-rock potential of the strata. The results indicate that the Road River Formation (Cambrian to Devonian) has no source rock potential, but the Bonnet Plume Formation (Cretaceous to Tertiary) has gas and perhaps oil potential. Potential oil generation in the Bonnet Plume Formation is attributed to the occurrence of liptinite-bearing coal and previously unrecognized, siliceous, oil shale. A hydrocarbon-rich tar associated with a naturally burning coal seam was also discovered in the Bonnet Plume Formation.

not_specified

A copy of this thesis is available at the EMR library – QE195 L56 1988. This thesis is available online at http://hdl.handle.net/2429/27980.

The southwestern Yukon Coast Belt mapping project is a joint Yukon Geological Survey/Geological Survey of Canada initiative operated under Natural Resources Canada’s GEM (Geomapping for Energy and Minerals) program. This project is aimed at investigating the geological relationships and mineral potential of the Kluane Schist, the Ruby Range batholith and the Yukon-Tanana terrane in southwestern Yukon. Bedrock mapping at 1:50 000-scale followed a 400 m line-spaced aeromagnetic survey flown in the winter of 2010. Preliminary results indicate the presence of a northeast-dipping structural stack through an ~40 km-thick crustal section, whereby the Kluane Schist occupies the lowest structural level and the Yukon-Tanana terrane the highest. The Ruby Range batholith intruded along the contact between the Kluane Schist and the Yukon-Tanana terrane, and was emplaced late in the deformation history. An orthogneiss/paragneiss unit of unknown tectonic affinity was mapped structurally between the Ruby Range and the Kluane Schist. Detrital zircon analyses from two samples of Kluane Schist indicate that the onset of deposition for this metasedimentary sequence occurred after ca. 94 Ma. Two significant metamorphic events, dated at 82 and 70 Ma, affected the Kluane Schist. This indicates that original structural juxtaposition between the Kluane Schist and the Yukon-Tanana terrane pre-dated intrusion of the Ruby Range batholith. Mineral potential in the Coast Belt area is significant and includes porphyry Cu-Mo-Au, epithermal Au-Ag and orogenic Au occurrences. The upper level of the Ruby Range batholith is most prospective for porphyry and epithermal mineralization, while the Kluane Schist is most prospective for orogenic Au mineralization.