AndreaBozzo/ceres-open-data-index huggingface dataset:
Geology and alteration of the Grew Creek epithermal gold-silver prospect, south-central Yukon

Grew Creek epithermal gold prospect, in south-central Yukon Territory, is adjacent to and southwest of the Robert Campbell Highway, halfway between the communities of Ross River and Faro. The prospect is within the Tintina Trench, which from Late Cretaceous to Tertiary time was a zone of major right lateral movement that juxtaposed the Cambrian and Ordovician slate and phyllites of the Pelly-Cassiar Platform (to the southwest) against rocks of the Anvil Allochthon (to the northeast).

Grew Creek rocks are mid-Eocene based on K-Ar dates of basalt of 51.4 ±1.8 Ma and 50.7 ±1.8 Ma and pollen spores in volcaniclastic rock dated at 56 to 46 Ma. Felsic volcanic and volcaniclastic rocks were overlain by a sequence of interbedded coarse clastic sediments, basaltic flows, and basaltic volcaniclastic rock. Late Tertiary uplift and faulting resulted in graben formation and consequent preservation of Eocene rocks in a structurally complex graben bounded to the south by the Grew Creek fault and to the north by the Danger Creek fault.

Mineralization at Grew Creek occurs at the tip of a westwardly pointing wedge of dominantly felsic, crystal lithic lapilli tuff. The zone of precious metal deposition is truncated to the northeast by steeply dipping clastic sediments and to the southwest by the Grew Creek Fault. Gold, electrum, pyrite, and silver selenide were identified in a high grade sample from the discovery outcrop.

Alteration at Grew Creek is both surficial and hydrothermal. Surficial alteration is ubiquitous, pervasive, and characterized by mixed-layer clays and carbonates. Hydrothermal alteration, responsible for the gold-silver mineralization is closely associated with rhyolitic dykes and is of three types:: silicic, acid sulphate, and argillic acid sulphate. K-Ar dating of sericite indicates hydrothermal alteration is mid-Eocene (51.5 ±1.8 Ma and 47.0 ±1.7 Ma) and synchronous with deposition of the volcanics.

Quartz associated with mineralization at Grew Creek is enriched in heavy oxygen isotopes. A deep magmatic source for the mineralized fluids is one explanation for this enrichment.

Organization: Government of Yukon | Gouvernement du Yukon
New bedrock geology of Mount Mervyn map sheet (106C/04) and mineral potential for the South Wernecke mapping project.

An integrated bedrock mapping and regional soil sampling program in the Mount Mervyn map area (106C/04) was undertaken in 2010. It is the first year of a multi-year initiative called the South Wernecke mapping project (SWP), which will cover ten 1:50K map sheets in the southern Wernecke Mountains area in central Yukon. Field work in the first year served to highlight the complexities of the bedrock geology in the region, and identify areas of mineral potential.

The Mount Mervyn map sheet is underlain by Proterozoic and Paleozoic siliciclastic and carbonate rocks that have been deformed into an east-trending fold-and-thrust belt. Regional soil geochemical data coupled with bedrock observations highlight new areas of mineral potential (i.e., Ni and Au) that have not been previously identified.

Organization: Government of Yukon | Gouvernement du Yukon
Stratigraphy of the Faro Peak formation, central Yukon: New field observations of Jurassic synorogenic sedimentation along the Yukon-Tanana–Slide Mountain terrane boundary

The Faro Peak formation is a Lower Jurassic(?) unit assigned to the Yukon-Tanana terrane in the southern Tay River map area (NTS 105K). A two-year project was initiated in 2018 to investigate the Faro Peak formation and constrain its stratigraphy, age, and significance to Cordilleran tectonic evolution. The exposed base of the Faro Peak formation includes argillite and organized to disorganized sandstone units that crop out southwest of the Yukon-Tanana–Slide Mountain terrane boundary near Faro. Lower Faro Peak formation units have mafic-intermediate volcanic provenance and were deposited by concentrated density flows or turbidity currents. The upper Faro Peak formation contains massive, disorganized conglomerate and sandstone units that were sourced from the Yukon-Tanana and Slide Mountain terranes and deposited by non-turbulent debris or density flows. The Faro Peak formation is likely the remnant of a synorogenic basin that formed as a result of Intermontane belt exhumation in central Yukon.

Organization: Government of Yukon | Gouvernement du Yukon
Surficial geology of Talbot Creek (115G/09), Yukon (1: 50 000 scale)

The Talbot Creek map area straddles the Ruby and Nisling ranges. Broad treeless uplands dominate the landscape with summits reaching 2100 m above sea level in the Ruby Range and 1800 m above sea level in the Nisling Range. Upland surfaces are covered with weathered bedrock colluvium and sporadically distributed till deposits from former alpine glaciers and ice sheets. Upland surficial deposits are affected by active periglacial processes such as cryoturbation, nivation and solifluction.

Organization: Government of Yukon | Gouvernement du Yukon
Residual total magnetic field, McQuesten Aeromagnetic Survey, NTS 115I/13 and 115I/14, Yukon

A map of the residual total magnetic field derived from data acquired by Goldak Airborne Surveys during the period of November 19, 2008 to February 19, 2009. Data were recorded using a split-beam cesium vapour magnetometer mounted in the tail boom of a Piper Navajo aircraft.

Organization: Government of Yukon | Gouvernement du Yukon
Yukon Forum newsletters

[Yukon Forum](https://yukon.ca/en/your-government/find-out-what-government-doing/yukon-forum) newsletters published from 2018 to 2020. 

They provide a high-level overview of topics discussed at Yukon Forums from 2018 to 2020 as well as information on the Joint Working Groups of the Yukon Forum Joint Priority Action Plan.

Organization: Government of Yukon | Gouvernement du Yukon
Keno Hill Mining Camp

This Miscellaneous Report includes the presentation that was prepared to accompany the release of YGS Open File 2020-42, Geology of the Keno Hill district by Peter Read, Al McOnie and Seymour Iles, and presented at the 2020 Virtual Yukon Geoscience Forum in November 2020. The authors have prepared this version along with detailed notes in order to support the release of their new map for the Keno Hill district. The notes provided in this companion report will greatly facilitate the exploration of the many details included on the maps and cross sections in Open File 2020-42.

Organization: Government of Yukon | Gouvernement du Yukon
Geology and mineral occurrences of the Quartet Lakes map area (NTS 106E/1), Wernecke and Mackenzie mountains, Yukon

The Quartet Lakes map area is underlain by rocks that range in age from Early Proterozoic to early Paleozoic. Stratified rocks include, from oldest to youngest, the Lower Proterozoic Fairchild Lake and Quartet groups (Wernecke Supergroup), the Middle to Late Proterozoic Tsezotene Formation, Katherine Group, and Little Dal Formation Mackenzie Mountains Supergroup), and the Cambrian Slats Creek Formation. Five igneous units are recognized, including the Early Proterozoic Bonnet Plume River Intrusions, the Middle Proterozoic Bear River dykes, the Late Proterozoic Tsezotene Sills, Late Proterozoic to Cambrian lamprophyre, and Late Proterozoic to early Paleozoic diorite. Older rocks (Wernecke Supergroup, Wernecke Breccia and Bonnet Plume River Intrusions) were thrust northward over the Mackenzie Mountains Supergroup along a portion of the Knorr Fault. This part of the fault may be a restraining bend in an otherwise dextral strike-slip system. Copper-golduranium mineral occurrences in the area include disseminated and vein mineralization associated with zones of Wernecke Breccia.

Organization: Government of Yukon | Gouvernement du Yukon
Protopiceoxylon yukonense sp. nov. – A remarkable extinct conifer from the Mackenzie Delta area, northern Yukon

A fossil wood remain of par-autochthonous origin was found in Paleocene sedimentary rocks of the Moose Channel Formation in the Big Fish River area in Yukon, close to the Northwest Territories border, during the CASE 15 expedition. The fossil wood was recovered from overall medium to coarse-grained units of sandstone of an inferred fluvial-deltaic origin. This contribution summarizes the current knowledge primarily on the taxonomy and paleoecology of the protopiceaceous wood specimen. The fossil wood specimen turned out to be without a relationship to extant taxa: Protopiceoxylon yukonense sp. nov. as a taxon of the fossil wood genus Protopiceoxylon Gothan 1907 belongs to the extinct family of Protopinaceae Kraeusel, 1949. The holo- and paratypes of the generotypus Protopiceoxylon extinctum Gothan, 1907 from the King Charles Land (Gothan, 1907) and from Green Harbour/Spitsbergen (Gothan, 1910), were available for this investigation from the Natural History Museum Berlin (NHMB). Although most of samples characteristics are comparable to be extinct genus Protopiceoxylon, it is differentiated by some extinct anatomical features that are intermediate between the extinct Protopiceoxylon and the extant Piceoxylon Gothan, 1905. These features manifest within the radial bordered pits, which are protopinoid in Protopiceoxylon and abietoid in Piceoxylon. Most other features demonstrate a close relationship between both fossil taxa.

Organization: Government of Yukon | Gouvernement du Yukon
Geology of the EPD Stanniferous Breccia Deposit, McQuesten Area, 115 P, Yukon

The EPD property is located in central Yukon, 30 km northwest of Mayo, just south of the McQuesten River. Tin, zinc, and silver anomalies found in stream sediment samples of Oliver Creek led to staking of the EPD claims in 1978. This paper is based on detailed logging of drill core in the summer of 1982 supplemented by petrography of selected samples, and geochemistry values for sections of the drill core. This preliminary report outlines the geology, mineralogy and petrogenesis of the EPD stanniferous breccia. Further laboratory studies will be incorporated in an M.Sc. Thesis at Carleton University, Ottawa, Ontario.

Organization: Government of Yukon | Gouvernement du Yukon
Regional stream sediment geochemical data, Mayo area, central Yukon (NTS 105M)

NGR surveys were originally conducted in the Mayo map area in 1987 and 1988. Stream sediment and water samples were collected from a total of 861 sample sites. A total of 861 original samples were selected for reanalysis. Representative 2 gram splits were successfully recovered from 861 samples. Samples were analysed by an ultra-trace aqua-regia digestion ICP-MS package for 53 elements.

Organization: Government of Yukon | Gouvernement du Yukon
Cenozoic faulting in the Upper Hyland River Valley, Southeastern Yukon: A thermochronological perspective

The Logan fault is one of many dextral faults that strike generally parallel to the northwest trend of the Northern Canadian Cordillera. Though widely documented, the timing and magnitude of displacement on many of these orogen-parallel faults are not well-constrained. Here, we present new low-temperature thermochronology data and thermal history models from the Upper Hyland River Valley area in the Logan Mountains in southeastern Yukon that document accelerated cooling between ca. 60–50 Ma in localized regions adjacent to faults that strike obliquely to and likely connect with the Logan fault. We propose that this phase of localized cooling was driven by the activation of a network of faults in the Upper Hyland River Valley, resulting in ∼4–5.5 km of local exhumation. We suggest that faulting in the Upper Hyland River Valley was synthetic with dextral slip on the Tintina fault, a lithospheric-scale structure thought to have accommodated ∼430 km of dextral strike-slip.

Organization: Government of Yukon | Gouvernement du Yukon
Devonian-Mississippian metavolcanic stratigraphy, massive sulphide potential and structural re-interpretation of Yukon-Tanana Terrane south of the Finlayson Lake massive sulphide district, southeastern Yukon (105G/1, 105H/3,4,5)

Upper Devonian and Lower Mississippian metavolcanic rocks of Yukon-Tanana Terrane in southern Finlayson Lake and Frances Lake map areas occur in three thrust sheets, locally modified by a Cretaceous normal fault. The lower thrust sheet, the Big Campbell sheet, comprises the Upper Devonian to Lower Mississippian metavolcanic stratigraphy that hosts the main volcanichosted massive sulphide (VHMS) deposits of the district. Metavolcanic rocks in the middle thrust sheet, the Money Creek sheet, include the Upper Devonian Waters Creek and Early Mississippian Tuchitua River formations. The former comprises primarily felsic metavolcanic rocks and carbonaceous phyllite and is extensively intruded by sheets of comagmatic porphyry. The latter comprises primarily intermediate metavolcanic, volcaniclastic and epiclastic rocks. The upper thrust sheet, the Cleaver Lake sheet, is in part made up of Late Devonian calc-alkaline basalt and rhyolite, the Cleaver Lake formation, and comagmatic felsic to ultramafic plutonic rocks. Of these, the Waters Creek formation and the formations in the Big Campbell sheet have the highest potential to host VHMS deposits.

Organization: Government of Yukon | Gouvernement du Yukon
Preliminary data from the establishment of longterm ground temperature reference sites in five Yukon communities

A drilling program was conducted in fall 2023 to install deep (up to 35 m) ground temperature monitoring boreholes in communities at risk from permafrost thaw. These boreholes will serve as long-term reference sites in both undisturbed and developed locations within or adjacent to communities. These boreholes also filled knowledge gaps that included the thickness of permafrost, and temperature data at the bottom of permafrost. Prior to this program, only 3 of the 34 permafrost-monitoring boreholes managed by the Yukon Geological Survey recorded temperatures through to the bottom of permafrost; furthermore, none of these boreholes are in the extensive discontinuous or continuous permafrost zones. Fifteen boreholes were drilled in five different communities across the Yukon: Dawson City, Mayo, Ross River, Beaver Creek and Haines Junction. Permafrost was encountered in 10 of the 15 boreholes, and the bottom of permafrost, or bedrock, was reached in at least one borehole in each community.

Organization: Government of Yukon | Gouvernement du Yukon
Exploration Criteria For Coloured Gemstone Deposits in Yukon

This report is an updated version of an Open File report (Walton, 1996) describing the geology and geochemistry of gemstone deposits and applicable exploration criteria.The 1996 report, and this update, are both aimed at exploration geologists and prospectors who are unfamiliar with the geology of gemstone deposits and how to explore for them. Its objective is to provide information on gemstone deposit geology and provide general guidelines for the identification of, and exploration for, gemstone occurrences. The report focuses on a selection of some of the most valuable gemstones in the global gem trade: ruby, sapphire, emerald, chrysoberyl, tsavorite garnet, tanzanite and the gem minerals (topaz, aquamarine, tourmaline) found in permatites or rhyolites. Exploration criteria for other gemstones such as opal, nephrite jade, jadeite jade, zircon, lapis lazuli and rhondonite are beyond the scope of this report.
For each gem mineral covered in this report, background information is introduced and the physical and chemical characteristics of the gem are presented. The geology and genesis of each gem deposit type is summarized and exploration guidelines are listed. One of the difficulties in developing exploration guidelines is that many of the world's gem deposits are unique. It is difficult to determine the range of variations and physico-chemical conditions under which a particular type of gemstone deposit may form, if there is only one deposit to study.

Organization: Government of Yukon | Gouvernement du Yukon
The Pattison Creek pluton - a mineralized Casino Intrusion made bigger with gamma rays

Results from an airborne gamma ray and magnetics survey in the Dawson Range in west-central Yukon indicate that the Pattison Creek pluton may be larger than currently mapped. Ground follow-up indicates that the pluton is approximately three times larger than originally shown. This pluton is a member of the Casino Intrusions - a unit identified as being genetically associated with copper-molybdenum mineralization and as such is considered a good exploration target. Examination of the pluton indicates that it is a highly fractionated, epizonal stock composed primarily of granite and alkali feldspar granite with later phases of peraluminous muscovite-bearing alaskite and aplite. Microthermometric and isotopic data indicate that mineralizing hydrothermal fluids are of low salinity, and depleted in deuterium and delta Oxygen-18 relative to values typical of magmatic waters. The gamma-ray survey shows it to have among the highest U and Th values in the survey area (> 3.0 and 15 ppm respectively).

Organization: Government of Yukon | Gouvernement du Yukon
High-sulphidation epithermal Au-Ag-Cu mineralization at the McKay Hill property — a revised deposit model

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.

Organization: Government of Yukon | Gouvernement du Yukon
Geology, mineralization, and K-Ar and Rb-Sr isotopic study of the RAM zinc-lead-silver property Yukon Plateau, southwest Yukon Territory (105D/4)

The RAM zinc-lead-silver property in southwest Yukon Territory (105 D/4) is on the contact between metamorphic rocks of the Yukon Crystalline Terrane and foliated granitic rocks of the Coast Plutonic Complex. Both are intruded by an Eocene granitic stock. The metamorphic rocks, predominantly biotite-quartz pelitic schists, with amphibolite, marble, graphitic phyllite and foliated metagranite, may be partly Precambrian and are modified by metamorphism. Foliated granodiorite to quartz diorite of the Coast Plutonic Complex intrudes the metamorphic rocks. Rb-Sr analyses of two of these granitic rocks give a possible whole rock date for foliated granite of 143 Ma (initial 87Sr/86 Sr ratio of 0.7068), and a maximum age of 200 Ma, while K-Ar dating of hornblende and biotite separates from a granodiorite gives 106 ±4 Ma and 53.7 ±1.9 Ma, respectively. An Eocene, porphyritic microgranite stock (Rb-Sr whole rock date:: 43 Ma with assumed initial 87Sr/86Sr ratio of 0.705) discordantly crosscuts the older rocks on the property, and has probably reset the biotite K-Ar date in the granodiorite.

Mineralization on the property includes small skarns (maximum size 15m x 6 m) with disseminated sphalerite and galena, in metasedimentary rocks of the Yukon Crystalline Terrane, near the Eocene stock. Assay of grab samples from the showings average 53.8 gm/t silver, 4.35% zinc, and 2.20% lead.

Organization: Government of Yukon | Gouvernement du Yukon
Regional stream sediment geochemical data, McQuesten area, central Yukon (NTS 115P)

NGR surveys were originally conducted in the McQuesten map area in 1987 and 1988. Stream sediment and water samples were collected from a total of 841 sample sites. A total of 841 original samples were selected for reanalysis. Representative 2 gram splits were successfully recovered from 840 samples. Samples were analysed by an ultra-trace aqua-regia digestion ICP-MS package for 53 elements.

Organization: Government of Yukon | Gouvernement du Yukon
Munson property, south Yukon

The Munson occurrence consists of massive black sphalerite, galena chalcopyrite, pyrrhotite and magnetite exposed in bulldozer trenches on the floor of a cirque. The sulphides are associated with siliceous breccia and actinolite skarn along the contact betweeen siliceous metavolcanic rocks and limestone which also passes through the Mod showing, 2.4 km to the west. The contact appears locally discordant and is interpreted as a steep reverse fault.

Organization: Government of Yukon | Gouvernement du Yukon
The paleogeography of glacial lake Laberge.

During retreat of the Cassiar lobe of the Cordilleran ice sheet from the last glacial maximum there was a large stagnation or re-advance near what is now the north end of Lake Laberge (Lower Laberge) in the south central Yukon. This stagnation generated a large moraine that would come to act as a sediment dam for Glacial Lake Laberge. As the retreat of the ice front resumed a lake formed between the ice front to the south, and the sediment dam to the north. With the ice front continually drawing further south, combined with incision of an outlet flow into the sediment dam, the geomorphology of Glacial Lake Laberge constantly changed. Throughout the history of Glacial Lake Laberge there has been a gradual decline in the lake level largely controlled by incision into the sediment dam near Lower Laberge, as is indicated from sets of fluvial terraces above the current outlet river (the Yukon River). This gradual decline has produced several sets of preserved shorelines rising above the present lake level. By surveying the shape, location, and elevation of these shorelines and outwash terraces, in combination of all other applicable data sets, a detailed glacial retreat and alluvial history can be examined.

Organization: Government of Yukon | Gouvernement du Yukon
Preliminary Geological Map of Little Salmon Range (Parts of 105L/1, 2 & 7), Central Yukon (1:50 000 scale)

Preliminary geological map (1:50,000 scale) of Little Salmon Range, central Yukon (parts of NTS 105L/1, 2 and 7) including geological cross sections, mineral occurrences, fossil localities and geochronology.

Organization: Government of Yukon | Gouvernement du Yukon
Update on the bedrock geology of the Rusty Mountain area, southern Wernecke Mountains, Yukon (parts of NTS 106C/4, 5, 12 and 106D/1, 8)

The Rusty Mountain area is underlain by sedimentary strata of the Paleoproterozoic Wernecke Supergroup, Mesoproterozoic Pinguicula Group, Neoproterozoic Hematite Creek Group and Windermere Supergroup, and Paleozoic Bouvette Formation. Three suites of intrusions are documented: (1) 10–200 m thick, subalkaline, mafic sills and dikes of the ca. 1380 Ma Hart River suite intrude the Wernecke Supergroup; (2) 2–3 m wide, vertical, east-west striking, alkaline, mafic dikes that are geochemically distinct from the Hart River suite intrude the Wernecke Supergroup; and (3) a 30 cm thick, mafic, porphyritic dike intrudes the Wernecke Supergroup at one locality. The main structures in the Wernecke Supergroup are northwest-verging folding and thrusting and a steeply dipping axial-planar cleavage. This deformation affected the Hart River sills, but not the east-west striking dikes. The main structures in the Pinguicula Group and younger strata are northwest-southeast trending gentle folds and a steeply dipping axial-planar cleavage.

Organization: Government of Yukon | Gouvernement du Yukon