AndreaBozzo/ceres-open-data-index huggingface dataset:
High Level Terraces Along Parts of Yukon River and Sixtymile River (115 N/9 East Half, 115 O/5, and 115 O/12), Yukon

High level terraces representing former valley bottom deposits exist along Yukon River and several of its tributaries. The terraces contain fluvial gravel deposits wich are veneered by loess. Soil development in the gravel suggest they predate the oldest Pleistocene glaciation in central Yukon..

These high terraces are given a Neogene age (Miocene-Pliocene) based on their relative heights and the ages of bedrock that they occur on. They may be the same age as White Channel gravel in Klondike area.

Along Yukon River their elevation varies from 43 to 88 m (140 ft to 290 ft) above present river level rising to the north. Flow directions based on imbrication measurements in pits indicate flow generally followed that of the modern Yukon River. The paleo-Yukon River flowed to the nroth when these gravels were laid down.

The reason why terrace elevations rise in elevation northward, opposite to the present drainage is presumed to be from tectonic warping. The area around Dawson was uplifted more than that near the mouth of Stewart River.

Placer gold was recovered in small quantities from test pits at several sites along the Yukon River and Sixtymile River valley. The gold is typically flat, fine grained and far-traveled; suggestive of deposition in a bar environment. The number of gold particles in gravel samples (each sample 23 litre volume) ranged from 0 to 1 in Sixtymile River valley and 0 to 12 in Yukon River valley terraces. Downcutting of Yukon River and its tributaries led to placer accumulations in the modern creeks. Highly anomalous arsenic in sediment soils from Ten Mile Creek drainage with coincident anomalous gold suggest gold-arsenopyrite veins as sources for placer gold in that creek.

Organization: Government of Yukon | Gouvernement du Yukon
Geochemistry and geochronology of Cambrian and Upper Ordovician mafic igneous rocks along the Dawson fault zone, Yukon

Neoproterozoic to lower Paleozoic basin and platform strata that formed during and after rifting along the western Laurentian margin are preserved in the northern Cordillera. Several pulses of magmatism occur within margin strata and are concentrated along the Dawson fault in central Yukon. Magmatism is dated as late Cambrian and Late Ordovician using: 1) U-Pb zircon geochronology of volcaniclastic rocks; and 2) fossil ages from strata interbedded with, and enclosing, volcanic rocks. Volcanic rocks from both pulses are predominantly alkaline and basic and erupted in subaqueous environments. The trace element geochemical compositions of the rocks suggest that they formed from partial melting of enriched lithosphere from the garnet stability field.

Organization: Government of Yukon | Gouvernement du Yukon
The McMillan Deposit - a stratabound lead-zinc-silver deposit in sedimentary rocks of Upper Proterozoic age, Yukon

The McMillan deposit is in the southern portion of the Logan Mountains, 65 km NE of Watson Lake. It is also referred to as the Quartz Lake deposit. Rocks hosting the deposit consist of argillite, sandstone, limestone and massive sulphides.

Mineralization includes concordant and discordant types. Concordant mineralization mainly consists of beds of massive sulphides with sphalerite, galena and carbonate (siderite?) with minor sulphosalts. Discordant mineralization is widespread and consists of veins and veinlets that cut layering and cleavage. Quartz-siderite is the most common vein filling.

Most stratabound deposits in Selwyn Basin are attributed to syngenetic origins. However, deposits similar in mineralogy and geologic setting to the McMillan deposit are thought to be of a replacement type origin. Two models are proposed for the origin of the McMillan deposit:: a) mineralization was hydrothermally introduced into a carbonate-rich post depositional sequence and selected limestone beds were replaced by sulphides and siderite, or b) the mineralization was hydrothermally introduced onto a seafloor and sulphides and siderite were precipitated as lateral facies equivalents of limestone.

Organization: Government of Yukon | Gouvernement du Yukon
Ross River geothermal exploration project: Review of the 2014 work program

The results of an integrated geothermal exploration program of part of the Tintina Trench near Ross River, Yukon.

The study was commissioned by the Dena Nezziddi Development Corp. of the Kaska First Nation, and benefited from funding by CanNor and the Government of Yukon. The Yukon Geological Survey provided geological advice.

Organization: Government of Yukon | Gouvernement du Yukon
Yukon Exploration and Geology 1994

Yukon Exploration and Geology 1994 consists of three parts: Part A is a comprehensive overview of mining and exploration activity in Yukon; Part B summarizes the activities of Government agencies which provide technical and financial assistance to the Yukon mining and exploration industries; and Part C consists primarily of geological reports by Canada/Yukon Geoscience Office geologists. Two outside reports are also included.

Organization: Government of Yukon | Gouvernement du Yukon
Yukon Geoscience Needs: Results of the Third Yukon Geoscience Planning Workshop

This is the third in a series of five-year planning documents that have guided government geoscience in Yukon over the last ten years. It presents a broad set of needs and priorities for Yukon geoscience for the next five years, but is not a business or work plan. Although developed primarily from the Yukon Geological Survey (YGS) perspective, the Geological Survey of Canada and universities will help to meet these needs either independently or through partnerships with the YGS. It was developed during the spring, summer of 2004 as an internal draft that was later modified and refined through consultation with the Geological Survey of Canada and the Technical Liaison Committee to the YGS. Over the last five years, the need for geoscience information has grown and spread to a wider and wider audience. Geoscience is utilized primarily by the mining and petroleum sectors to support exploration for minerals and hydrocarbons, but it is increasingly playing a role in other industries such as forestry, fisheries and tourism. In all of these industries it is playing a role in their development and management. Decisions related to the utilization of natural resources are increasingly being made or influenced by many groups including developers, land managers planners, regulators, First Nations, and the general public. Their decisions need to be formed with accurate information about the nature and potential of resources, and the best practices in mitigating and preventing environmental damage. This volume includes sections on: bedrock mapping, mineral deposit studies, mineral assessments, regional geochemical and geophysical surveys, subsurface geology, energy/hydrocarbons, surficial geology and placer deposits, information management and outreach.

Organization: Government of Yukon | Gouvernement du Yukon
Placer geology of Black Hills Creek (Parts of 115 O/7 and 10)

Mapping in the Black Hills Creek drainage has identified auriferous gravel resources in valley bottom and terrace deposits of the main stream. Both low-level and high-level terrace gravels and modern floodplain contain fine gold grains. Bulk gold counts determined from sluice box testing of 57 samples indicates concentrations decrease in the downvalley direction. Geochemical analysis of matrix samples (finer than 60 mesh) mimics bulk results. The apparent lower concentration of detrital gold in a downstream direction may be explained by lack of bedrock sources and insignificant enrichment from tributaries.

Bedrock terraces high above the creek level record periods of stability at high base levels which was followed by incision and aggradation of alluvial sediments in late Tertiary(?) time. Thick sediments in low-level terraces indicate a long period of aggradation followed by organic accumulation. Holocene activity has degraded the valley fill and redistributed sediment downstream in fining upward meander stream deposits. Permafrost is present in black muck sequences.

Organization: Government of Yukon | Gouvernement du Yukon
Winter Low Flow Stream Measurements Using the Salt Slug Injection Method

Assessing the impact of a mining project requires knowledge of the water balance. Study of stream flow variation over the open water season can be readily accomplished with a variety of conventional methods, but understanding the behaviour of streams in winter low flow is hampered by uncertainty. Knowledge of absolute low flow can be vital in anticipating environmental effects of mining projects and describing the possible effects of climate change.

Streamflow has been measured using variations of dye dilution and tracers of all kinds for many years, but these were always cumbersome. Recently, advances in instrumentation have allowed a variation of the salt dilution method to be a practical method for streamflow measurement.

Geoff Kite of the National Hydrology Research Institute (NHRI) has experimented with a streamflow measurement technique using injection of a salt slug and calculation of flow based on the conservation of mass. The method is described in re 'Measuring glacier outflows using a computerized conductivity system', Journal of Glaciology, Vol. 40, No. 134, 1994 (attached as Appendix A), and 'Computerized Streamflow Measurement Using Slug Injection', Hydrological Processes, Vol. 7, 227-223 (1993). A software program converts the conductivity readings to flow, with a computer coupled to the conductivity meter through digital/analog converter.

This report summarizes a project undertaken by Laberge Environmental Services for the Mining Environment Research Group (MERG) during the late winter low flow period of 1998/1999. The Salt Slug Injection method of stream flow monitoring as described by Kite was tested to determine its applicability to Yukon mining monitoring situations under late winter low flow conditions. Transfer of technology to user groups was accomplished through this report and accompanying information pamphlet, a workshop, and direct training experience.

Organization: Government of Yukon | Gouvernement du Yukon
Structural evolution of the Tally Ho shear zone (NTS 105D), southern Yukon

The Tally Ho shear zone is located along the western boundary of the Whitehorse Trough in southern Yukon, and separates the Stikine Terrane to the east and the Nisling Assemblage to the west. Complex geologic structures, Jurassic and Cretaceous plutonism and abundant Tertiary volcanism obscure the nature of this boundary and its relation to adjacent terranes. Pyroxenite, gabbro, marble, and highly strained volcaniclastic rocks form a 3-km-wide belt that is in intrusive and fault-contact with megacrystic granite and granodiorite, respectively. Structural relations in the field indicate that the ultramafic rocks in the Tally Ho shear zone are allochthonous, and have been thrust to their present position and subsequently folded in the Early Jurassic. Younger brittle and semi-brittle faulting occurred along the Llewellyn fault in the Late Cretaceous.

Organization: Government of Yukon | Gouvernement du Yukon
Drift prospecting for gold in the Tintina Trench

Two tills and related deposits are the products of at least two ice advances over the Tintina Trench near Ross River, Yukon Territory. These ice advances are termed the McConnell and pre-McConnell glaciations. Erosional remnants provide evidence of the pre-McConnell glaciation and indicate that the ice was flowing to the west or northwest. The onset of McConnell glaciation was marked by an early ice advance out of the Lapie River valley, which was followed by a general ice flow toward the west or northwest along the Tintina Trench. During the retreat of the McConnell glacier, an ice tongue advanced up the Lapie River valley, blocking the drainage and forming a glacial lake.

To develop and apply drift prospecting techniques in the Tintina Trench, 204 till samples were collected over the study area. The silt plus clay size fraction was analysed for Au and the clay fraction was analysed for 30 elements. Only Au, Ag, Hg and Sb results are discussed in this paper. The geochemical data for till down-ice from the Grew Creek Au-Ag mineralization (MINFILE 105K 009) show a dispersal train for gold, but not for pathfinder elements such as Ag, As, Hg and Sb. A possible relationship between Au and Tertiary volcanic rocks is illustrated. However, closer-spaced samples would have to be taken to verify this hypothesis, since the length of the Au dispersal train is about 500 m, much smaller than the sampling interval.

Organization: Government of Yukon | Gouvernement du Yukon
An overview of shale studies in Yukon during the 2017 field season

Summer 2017 fieldwork in Yukon’s lower Paleozoic shale basins (Selwyn basin and Richardson trough) involved participants from government geological surveys (Yukon Geological Survey, Geological Survey of Canada) and several universities (Queen’s, McGill, St. Francis Xavier, Stanford and Dartmouth College). Research interests include: 1) shale chemostratigraphy and biostratigraphy, and pyrite trace element geochemistry to characterize shale units and assess lower Paleozoic paleoenvironmental conditions and depositional controls; and 2) an assessment of hyper-enriched black shales, specifically the colloquial ‘Nick’ or ‘Ni-Mo’ mineralized Ni-Zn-Mo-PGE deposit, in order to develop internally consistent genetic and exploration models for these types of deposits. This paper describes individual research projects underway and summarizes fieldwork in summer 2017.

Organization: Government of Yukon | Gouvernement du Yukon
Surficial Geology of the Village of Mayo (parts of NTS 105M/12) Yukon (1:20 000-scale)

Local-scale surficial geology mapping was completed as part of a community hazards mapping program coordinated by the Northern Climate ExChange (Yukon Research Centre, Yukon College). This program assesses potential landscape hazards under changing future conditions by incorporating a variety of data sets, including surficial geology, topography (slope and aspect), permafrost distribution, site-specific permafrost data (e.g. ground penetrating radar, electrical resistivity tomography and borehole data), analyses of past hydrological and climatological trends, and future climate projections. The surficial geology map describes surface landscape features, sediment texture, genetic material, surface expression and geomorphological processes. Detailed descriptions of local surficial geology and hazard analysis methodology are presented in the accompanying report. The accompanying landscape hazard classification map identifies existing and potential geological hazards such as landslides, permafrost stability and flooding; the hazard map is presented in stoplight colours to provide an intuitive tool for community decision makers aiming to incorporate an adaptation planning framework into existing land use management practices.

Organization: Government of Yukon | Gouvernement du Yukon
Yukon Bathymetry Maps and Data

*Distributed by Yukon department of environment from 1990s to 2010s*

The *Yukon Bathymetry Maps* and associated data have been removed from distribution due to excessively poor accuracy. This record remains in Open Data so there is a public record of the removal, the reasons for removal, and to provide a landing page for people searching for it.

Organization: Government of Yukon | Gouvernement du Yukon
Geochemical characterization of Carboniferous volcanic successions from Yukon-Tanana Terrane, Glenlyon map area (105 L), central Yukon

Detailed mapping of Yukon-Tanana Terrane in Glenlyon map area has identified two Carboniferous volcanic successions, and their subvolcanic intrusions. The early-to mid-Mississippian Little Kalzas succession consists predominantly of calc-alkaline volcanic and volcaniclastic rocks which formed in a continental arc setting. Minor alkali basalt occurs stratigraphically below and above the calc-alkaline rocks.The Little Salmon succession, of mid-Mississippian to early Pennsylvanian age, represents a second cycle of continental arc magmatism. It consists of calc-alkaline andesite and volcaniclastic rocks near Little Salmon Lake, but passes laterally along strike to alkali basalt of within-plate affinity. The occurrence of alkaline magmatism within these continental arc sequences suggests episodic rifting of the arc. The occurrence of Mn-rich exhalite within the rifted arc sequence of the Little Salmon succession suggests that this environment may also have been favourable for production and deposition of metal-rich solutions.

Organization: Government of Yukon | Gouvernement du Yukon
Surficial geology and till geochemistry of Weasel Lake map area (105G/13), east-central Yukon

Weasel Lake map area (105G/13) is located at the northwestern end of the Finlayson Lake belt (displaced Yukon-Tanana Terrane) and extends northward into ancient North American rocks. Several volcanogenic massive sulphide deposits including: Wolverine, Kudz Ze Kayah, Fyre Lake and the Ice, have been discovered in this part of Yukon-Tanana Terrane, which makes this region one of the most prospective areas of Yukon. Limited outcrop exposure, due to widespread Quaternary cover, has made prospecting challenging in many parts of this terrane, including Weasel Lake map area. Surficial geological mapping and till geochemical sampling was conducted in the map area to better understand its mineral potential. Ice-flow over the area trended at approximately 305° and remained topographically unobstructed through the last glacial maximum. As a result, basal till was deposited across most of the map area. Late glacial deposition of glaciofluvial sediment and meltout till was more common in the northeast part of the map and along the Pelly River. Results of the till geochemical sampling program highlighted anomalies in base-metal elements, platinum/palladium indicators, as well as a gold indicator suite, suggestive of epithermal mineralization.

Organization: Government of Yukon | Gouvernement du Yukon
Surficial geology of Gladstone Creek (NTS 115G/8 and part of 115G/7)

The Gladstone Creek map area covers the central Ruby Range. This part of the Ruby Range is characterized by rugged peaks up to 2200 m, and broad undulating plateaus above 1500 m, drained by deep U-shaped valleys running roughly east-west through the map area. The majority of the map area drains west into Kluane Lake via Gladstone Creek in the south, and Raft Creek in the north. Isaac Creek and Albert Creek drain the east margin of the map area. Thick deposits of till, glaciolacustrine, and glaciofluvial sediments occur in valley bottoms. Incising through these sediments are modern creeks, exposing thick stratigraphic sequences. All but the gentlest slopes are covered by colluvium derived from weathered bedrock and till. The highest surfaces are composed of bedrock, or weathered bedrock where slopes are more stable.

Organization: Government of Yukon | Gouvernement du Yukon
Mid-Cretaceous orogenic gold and molybdenite mineralization in the Independence Creek area, Dawson Range, parts of NTS 115J/13 and 14

The Boulevard gold prospect, located in the Independence Creek area of the Dawson Range, comprises sheeted, auriferous quartz-sulphide-carbonate veins and fault breccia, hosted mainly by mafic schist. The nearby Toni Tiger molybdenum showing is characterized by quartz-molybdenite veins cutting Late Permian meta-aplite and garnet-pyroxene skarn of uncertain age. We present geochronological evidence that gold and molybdenum were deposited at 96-95 Ma, approximately 3 m.y. after intrusion of the Dawson Range batholith and Coffee Creek granite. Fluid inclusions from mineralized quartz veins suggests that gold at Boulevard and molybdenite at Toni Tiger were formed from similar H2O-CO2-NaCl type fluids between 279 and 310°C and >1 kbar. We conclude that both are part of the same mineralizing system, and that structurally-hosted gold at the nearby Coffee deposit and in the Moosehorn Range of western Yukon may be broadly related, post-arc orogenic systems developed during exhumation of the Dawson Range in mid-Cretaceous time.

Organization: Government of Yukon | Gouvernement du Yukon
First vertical derivative of the magnetic field, Wernecke Mountain Aeromagnetic Survey, NTS 106B (south half), Yukon

This map of the first vertical derivative of the magnetic field was derived from data acquired during an aeromagnetic survey carried out by Fugro Airborne Surveys during the period April 17, 2006 to August 26, 2007. The data were recorded using a split-beam cesium vapour magnetometer (sensitivity = 0.005 nT) mounted in the tail boom of a Cessna Caravan aircraft. The nominal traverse and control line spacings were, respectively, 800 m and 2 600 m, and the aircraft flew at a nominal terrain clearance of 250 m. Traverse lines were oriented N30degreesE with orthogonal control lines. The flight path was recovered following post-flight differential corrections to the raw Global Positioning System data and inspection of ground images recorded by a vertically-mounted video camera. The survey was flown on a pre-determined flight surface to minimize differences in magnetic values at the intersections of control and traverse lines. These differences were computer-analysed to obtain a mutually levelled set of flight-line magnetic data. The levelled values were then interpolated to a 200 m grid. The International Geomagnetic Reference Field was not removed from the magnetic total field.

The first vertical derivative of the magnetic field is the rate of change of the magnetic field in the vertical direction. Computation of the first vertical derivative removes long-wavelength features of the magnetic field and significantly improves the resolution of closely spaced and superposed anomalies. A property of first vertical derivative maps is the coincidence of the zero-value contour with vertical contacts at high magnetic latitudes (Hood, 1965).

Organization: Government of Yukon | Gouvernement du Yukon
Triassic overlap assemblages in the northern Cordillera: Preliminary results from the type section of the Jones Lake Formation, Yukon and Northwest Territories (NTS 105I/13)

We present new field and whole-rock geochemical data from the type section of the Triassic Jones Lake Formation (JLF) located along the Yukon-Northwest Territories border in the Nahanni map area (NTS 105I/13). The type section is the first location of a regional-scale study that investigates the nature of Triassic siliciclastic rocks, and tests the presence of an overlap assemblage linking pericratonic terranes with North America by the Triassic, instead of Early to Middle Jurassic. The JLF is composed of carbonaceous shale and ripple cross-laminated calcareous sandstone thought to be associated with the Cordilleran miogeocline, and is devoid of sediment sourced from terranes to the west. Whole-rock shale geochemistry has provided evidence that the JLF is distinguishable from the underlying Mount Christie Formation and has trace and rare earth element concentrations that are most similar to old continental crust. However, the JLF does contain geochemical signatures suggestive of a minor mafic component.

Organization: Government of Yukon | Gouvernement du Yukon