AndreaBozzo/ceres-open-data-index huggingface dataset:
Total field magnetic, Wernecke Mountain Aeromagnetic Survey, NTS 106E (south half), Yukon

This map of the magnetic total 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 2600 m, and the aircraft flew at a nominal terrain clearance of 250 m. Traverse lines were oriented N30 degrees E 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.

Organization: Government of Yukon | Gouvernement du Yukon
The deforming bed beneath a surge-type glacier; measurement of mechanical and electrical properties

Glacier surging is a flow instability characterized by short periods of rapid glacier flow separating longer periods of normal flow. It is accepted that sustained high sub-glacial water pressure causes glacier surging by decoupling the glacier from its bed, but how this high subglacial water pressure is developed and sustained is the subject of debate. The current focus of glaciological research is on the interaction of subglacial processes with the subglacial drainage system. We have developed new investigative techniques for exploring two subglacial processes: basal deformation and electrical phenomena. These techniques have been plied in research undertaken on Trapridge Glacier, a small surge-type glacier in the St. Elias Mountains, Yukon, Canada; these are the first in situ measurements of deformation, electrical resistivity, and streaming potentials beneath a surge-type glacier. The development of a reliable theological description of subglacial material required field observations of its stress-strain response; this was the motivation for our subglacial deformation experiments. We have demonstrated that no clear relationship exists between values of shear stress and effective pressure calculated using accepted methods and deformation rate; the absence of an expected relationship suggests that alternate methods for quantifying subglacial shear stress and effective pressure need to be found. Data from our subglacial electrical resistivity measurements and from the deformation measurements provide strong evidence that the distribution of normal and shear loading at the glacier bed is not even and that subglacial deformation rates can be affected by distant changes in subglacial pressure conditions. We have also observed temporal changes in electrical flow paths within subglacial sediments. We have shown that temporal variations in natural potential observed beneath Trapridge Glacier are caused by streaming potentials; streaming potentials result from cross-coupling between fluid flow and electric currents. Our data suggest that inexpensive subglacial electrode arrays may be used to supplement pressure sensors.

Organization: Government of Yukon | Gouvernement du Yukon
2003–04 Supplementary estimates no. 1

Supplementary estimates no. 1 for the Government of Yukon 2003–04 Budget. 
This document was prepared by the Department of Finance under the direction of Management Board for the 1st Session of the 31st Legislature, Yukon Legislative Assembly. October 2003, Whitehorse, Yukon.

Organization: Government of Yukon | Gouvernement du Yukon
Baseline Science Review

The Government of Yukon Science Strategy was released in 2016 to provide a strategic framework for building Yukon’s science capacity, in support of evidence-based decision making, innovation and economic diversification. This Baseline Assessment provides guidance for ongoing work, and a starting point against which progress can be measured, for the thorough evaluation to be completed by March 31, 2025. The evaluation will assess the relevance and design of the Science Strategy as well as the resulting outcomes.

Organization: Government of Yukon | Gouvernement du Yukon
Permo-Triassic Isotopic Dates for Blueschist, Ross River Area, Yukon

Rb-Sr and K-Ar age determinations for muscovite-bearing blueschist in the Yukon Tanana terrane near Ross River indicate a minimum metamorphic age of approximately 250 Ma, and a mid-Paleozoic protolith age. The blueschist is associated with eclogite in a tectonized assemblage of phyllite, quartzite, micaschist and serpentinite. Neither mid-Jurassic metamorphism nor mid-Cretaceous regional plutonism have affected these high-pressure rocks to the point of resetting the isotopic systems. Parts of the Yukon Tanana terrane thus record a Late Paleozoic metamorphism. If the blueschist and eclogite were part of the trench melange of the Lewes River Arc, their age implies that the arc was active in Late Paleozoic time.

Organization: Government of Yukon | Gouvernement du Yukon
2006–07 Supplementary estimates no. 2

Supplementary estimates no. 2 for the Government of Yukon 2006–07 Budget. 
This document was prepared by the Department of Finance under the direction of Management Board for the 1st Session of the 32nd Legislature, Yukon Legislative Assembly. March 2007, Whitehorse, Yukon.

Organization: Government of Yukon | Gouvernement du Yukon
Late Cenozoic history of McQuesten map area, Yukon Territory, with applications to placer gold research

The late Cenozoic history of McQuesten map area is characterized by progressively less extensive glaciations and deteriorating interglacial climates. The glaciations, from oldest to youngest, are the pre-Reid (a minimum of two early to mid Pleistocene glaciations), Reid (>200 ka), and McConnell (<29.6 ka BP). Pre-Reid interglacial reconstructions suggest a much warmer and more humid climate than today. The Koy-Yukon interglacial (200 ka) is considered to have a climate similar to a southern boreal forest and the first intact Diversion Creek paleosol, from this period, is documented in the McQuesten River valley. The Stewart neosol (Holocene) is widespread and poorly developed in comparison to past interglacial soils. The distribution of surficial deposits, related to multiple glaciations, physiography, and fluvial order contrasts, may govern the distribution of placer gold occurrences in the study area. Placer deposits occur anomalously in areas outside the pre-Reid limit on Klondike Plateau, and on Stewart Plateau.

A copy of this thesis is available at the EMR library – QE195.B65 1997.
This thesis is available online at https://www.collectionscanada.gc.ca/obj/s4/f2/dsk2/ftp04/mq21154.pdf

Organization: Government of Yukon | Gouvernement du Yukon
New geochemistry from old drill holes at the Tom property, Macmillan Pass, Yukon

This paper presents new data from historical drill core and outcrop specimens from Macmillan Pass, Yukon. Whole rock lithogeochemical data are presented from analyses of core from three drillholes at the Tom property. The core covers intervals ranging from the Middle Devonian Road River Group (Sapper Formation) to the Upper Devonian Earn Group (Portrait Lake Formation–Fuller Lake Member) and includes the Macmillan Pass volcanic suite that occurs at the Road River–Earn Group contact. Samples were collected to characterize the depositional history of Middle–Upper Devonian fine-grained rocks in the region to aid with paleogeographical reconstructions, depositional models, improve age control and to aid in correlation of thick shale units. Baseline geochemical profiles and sedimentology for all fine-grained units indicate turbidity current deposition in a range of shelf to basinal settings and variable oxic to anoxic conditions. Additionally, eleven existing Middle Devonian conodont collections were re-examined to provide better biozone refinements and a tighter constraint of the contact between the Road River Group (Sapper Formation) and Earn Group (Portrait Lake Formation) to the Late Eifelian australis-ensensis biozones.

Organization: Government of Yukon | Gouvernement du Yukon
Revisiting a resource: Yukon's "technogenic" placer deposits

In order to facilitate exploration and mining of placer gold in historic placer regions increasingly innovative mining and exploration methods must be employed.

Using a combination of historic and modern exploration tools, it is possible to delineate placer gold deposits in areas which were previously thought to be exhausted of reserves. These placer settings are sometimes referred to as ‘technogenic’, a term used to describe original gravel remnants and gold-bearing tailings which formed as a consequence of inefficient technology or poor mining techniques. These deposits may now be exploited using modern exploration and mining methods.

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

The Crescent occurrence consists of black sphalerite, pyrrhotite, pyrite and magnetite in garnet-diopside-epidote-actinolite skarn hosted by sheared, brecciated schist and hornfels near a fault-bounded slab of Jurassic diorite south of Crescent Lake. The mineralization is believed to have replaced brecciated calc-silicate rock in the footwall of a south-dipping thrust fault which passes through the Crescent Lake area and extends through the Dan prospect 5.8 km to the east.

Organization: Government of Yukon | Gouvernement du Yukon
An Analysis of Sluicebox Riffle Performance

The sluicebox is still the most popular placer gold recovery device in the Yukon because of its simplicity, reliability, low cost and very high concentration ratio. A sluicebox is a rectangular flume containing riffles on matting, through which a dilute slurry of water and alluvial gravel flows.

Two field sampling programs sponsored by the Klondike Placer Miners Association (Clarkson, 1989, 1990) provided valuable data regarding the gold recovery efficiency of a variety of sluiceboxes. However, they also posed many questions which could not be answered without resorting to testing under more controlled pilot-scale conditions.

A pilot scale testing facility was constructed at the Yukon College in Whitehorse. It used a gravel pump and cyclone to continuously cycle -1/2 inch placer gravel through an 8 feet by 6 inch wide sluice run. The sluice run was constructed with Plexiglass sides to allow visual interpretation. Several sizes, types, spacings and orientations of riffles were tested under a variety of feed rates, water rates and sluice run slopes to determine the optimal scour and deposition patterns.

Once the optimum conditions had been observed, the feed was salted with irradiated gold particles to confirm the riffle's effectiveness. In addition, the effects of Monsanto matting, suspended punch plate and the screening efficiency of stationary punch plate were also investigated.

Organization: Government of Yukon | Gouvernement du Yukon
Shrub-Trial Plots - Brewery Creek Mine 2006 Follow-up Monitoring Report

In order to determine which shrub species might be useful in revegetating Yukon mine sites at the time of closure, eleven species of shrubs were transplanted at three open disturbed sites at the Brewery Creek Mine in the Central Yukon in the fall of 2000. These sites included a steep north-facing slope, a steep south-facing slope, and a lower nearly level area. All three of these areas had been recontoured and seeded in 1996-97, and there was a thick growth of grasses and clovers at the time the shrubs were planted in 2000. To determine if this thick growth interfered with the survival of the newly planted shrubs, the grasses and clover were first removed from one-half of each of the test plots. Six years after the shrubs were planted, it appears that black spruce and Alaska birch are the most successful species transplanted on the north-facing site, trembling aspen and Alaska birch the most successful on the south-facing site, and dwarf birch, prickly rose and trembling aspen the most successful on the nearly level site. The planting of willow stem cuttings was not successful. After six years, the previously cleared half of each plot was once again covered with a thick growth of seeded and naturally occurring plant species. The clearing of vegetation before the transplanting of shrubs does not appear to have much of an effect on the ultimate survival and growth of the transplanted shrubs.

Organization: Government of Yukon | Gouvernement du Yukon
Field investigations of the Sugar gold prospect, Dawson Range, Yukon (NTS 115J/14 and 115J/15)

The Sugar gold prospect, located 20 km southeast of the Coffee gold deposits in Yukon, is hosted in the mid-Cretaceous Dawson Range batholith, of which three mappable sub-units are recognized: a biotite hornblende quartz monzodiorite; a K-feldspar phyric hornblende biotite syenogranite; and a biotite hornblende diorite. Plutonic rocks are cut by steep, west to northwest-striking andesite dikes of uncertain age. Alteration and mineralized zones coincide with fault-fracture zones that are parallel and proximal to dikes and their margins. Alteration is characterized by an early phase of calc-sodic (albite-amphibole) and potassic (pervasive biotite and fracture-controlled K-feldspar) alteration and a later phase of silica flooding and sericite alteration. Gold mineralization is associated with disseminated sulphides in zones of silica flooding and with variably sheared veins of quartz-carbonate-arsenopyrite ± pyrite ± freibergite ± stibnite ± sphalerite. Late chalcedonic quartz-carbonate and ferroan carbonate veins mark the collapse of the hydrothermal system.

Organization: Government of Yukon | Gouvernement du Yukon
First vertical derivative of the magnetic field, Wernecke Mountain Aeromagnetic Survey, NTS 106B (NW quadrant), 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
2000–01 Supplementary estimates no. 3

Supplementary estimates no. 3 for the Government of Yukon 2000–01 Budget. 
This document was prepared by the Department of Finance under the direction of Management Board for the 2nd Session of the 30th Legislature, Yukon Legislative Assembly. October 2001, Whitehorse, Yukon.

Organization: Government of Yukon | Gouvernement du Yukon
A Progress Report on Stratigraphic Investigations of the Lowermost Succession of Proterozoic Rocks, Northern Wernecke Mountains, Yukon

This interim report has reviewed stratigraphic characteristics of the lowermost succession of Proterozoic rocks exposed in the northern Wernecke Mountains. This sequence of rocks, which is in excess of 13 km thick, is named the Wernecke Supergroup. The Wernecke Supergroup is composed of three groups which from oldest to youngest are given the informal names Fairchild Lake Group, Quartet Group and Gillespie Lake Group. Several tentative subdivisions of formational status have been described in each of these groups.

The Fairchild Lake Group is composed of at least 4 km of generally light grey weathering siltstones, slates and argillites. It is divided into four formations, two of which contain carbonate members:: one formation near the middle of the group, contains ribbed weathering, thinly bedded, siltstone-limestone rhythmites; the other formation at the top of the group consists of interbedded shaly siltstone and dolostone with a distinctive white weathering limestone marker horizon. The Quartet Group, which conformably overlies the Fairchild Lake Group, consists of up to 5 km of monotonous dark grey weathering siltstone, argillite and slate with minor sandstone. The Quartet Group is transitional into the overlying Gillespie Lake Group which is compposed of at least 4 km buff to orange to locally grey weathering dolostone with minor siltstone and sandstone.

Metamorphism, faulting, complex folds, the monotonous and cyclical nature of stratigraphy, the lack of distinctive marker horizons and the possibility of facies changes have greatly hindered attempts at stratigraphic reconstruction in rocks of the Wernecke Supergroup. Thus much of the stratigraphic detail within the groups must be considered tentative in nature. Field investigations to be undertaken during the summer of 1978 will help further refine the stratigraphic relationships outlined above.

An Appendix to this report contains 19 representative stratigraphic sections which illustrate the main features of these rocks and a 1::250 000 location map showing where the sections are from.

Organization: Government of Yukon | Gouvernement du Yukon
Geology of the Aishihik Lake and Hopkins Lake Map Areas (115 H/6,7), Southwestern Yukon

Paleozoic and older metamorphic rocks in the Aishihik Lake and Hopkins Lake map areas (115 H/6 and 7) comprise the Aishihik Metamorphic Suite (AMS) and form a north-northwest-trending panel of rock that dips regionally to the east. The suite is divisible into a lower feldspathic quartz micaschist and marble package with a minor component of metaigneous rock and an upper package that includes black and brown quartzite, marble, metabasite and orthogneiss. Igneous rocks of three plutonic suites and one volcanic suite are present in the study area. Foliated hornblende granodiorite of the Aishihik Batholith, part of the Aishihik Plutonic Suite (APS), intruded in the Early Jurassic resulting in upper amphibolite grade metamorphism of the AMS. Relatively mafic APS plutonism evolved rapidly into more leucocratic quartz monzonite of the Early to Middle Jurassic Long Lake Plutonic Suite (LLPS). The Ruby Range Plutonic Suite (RRPS), including the Ruby Range Batholith and isolated stocks and tear-shaped plugs north of the batholith, intruded in the Late Cretaceous to Early Tertiary resulting in contact metamorphism and potassic metasomatism of the AMS. Sub-volcanic dykes and plugs that intrude the AMS are spatially associated with, and are thought to be genetically related to, Eocene strata of the Mount Creedon Volcanic Suite (MCVS). MCVS strata unconformably overlie all other rocks in the study area.

Potential exploration targets include:: massive sulphide deposits associated with black quartzite of the AMS; Cu skarn and porphyry deposits related to isolated stocks and tear shaped plutons of the RRPS; Cu-Au porphyry deposits associated with sub-volcanic plugs related to the MCVS; and mineralized east-trending quartz veins which may be related to a buried intrusion, possibly of the RRPS.

Organization: Government of Yukon | Gouvernement du Yukon
A review of placer gold concentrate recovery and upgrade options

In 2010-11, Yukon Geological Survey awarded a contract to NEW ERA Engineering Corporation of Whitehorse to undertake a study of recent developments in gravity gold recovery techniques. In partial fulfillment of the contract, Randy Clarkson attended the Gravity Gold 2010 Optimizing Recovery Conference in Ballarat, Australia, and presented the following report and recommendations at the Yukon Placer Workshop in November 2010.

Organization: Government of Yukon | Gouvernement du Yukon
Gold-sulphide quartz veins in metamorphic rocks as a possible source for placer gold in the Livingstone Creek area, Yukon Territory, Canada

The Livingstone Creek area is located 100 km northeast of Whitehorse, Yukon Territory, Canada. Hydrothermal gold-sulphide mineralization (MINFILE 105E 001) occurs in quartz-carbonate veins and veinlets which cut Paleozoic metamorphic rocks of the Teslin Suture Zone. The metamorphic rocks are also cut by Cretaceous(?) feldspar-porphyry dykes with an average thickness of 2 m.

The mineralization appears to be structurally controlled by NNE-striking faults and a set of NNW-trending joints. The vein minerals consist of gold, pyrite, chalcopyrite, galena, hessite/stuetzite, tetradymite, Au-Ag tellurides, tennantite, hematite, pyrrhotite, quartz, and carbonate. Gold occurs as: 1) "free gold" in cracks and interstices of quartz gangue, 2) inclusions in galena, usually rimmed by hessite, 3) minute grains associated with chalcopyrite and galena in aggregates of coarse-grained pyrite and 4) individual grains or fracture fillings in iron hydroxides.

The coarse-grained gold in Livingstone Creek appears to be derived from gold-quartz veins in the metamorphic bedrock. This is indicated by: 1) similar silver and mercury contents in primary and placer gold 2) identical trace element composition of galena from gold-quartz veins and galena inclusions in placer gold, 3) similar telluride mineral assemblages in both gold-quartz veins and placer gold grains and 4) similar homogenization temperatures and salinities in fluid inclusions from both gold-quartz veins and placer nuggets.

A limited amount of gold appears to have formed by supergene leaching and precipitation. This kind of gold occurs as irregular-shapd grains in the stream placers and in iron hydroxide along fractures in quartz veins. Relative to the pirmary gold it is enriched in silver and mercury.

Organization: Government of Yukon | Gouvernement du Yukon
Bimodal Volcanism Along the Tintina Trench, Near Faro and Ross River

Bimodal Tertiary volcanic rocks are exposed along the Tintina Trench in central Yukon in the Glenlyon, Grew Creek, and Ketza areas. Basalt and rhyolite are interbedded with coarse sedimentary rocks and preserved in grabens. The basalt forms both subaqueous and subaerial flows, hydrovolcaniclastic, pyroclastic, and autoclastic deposits. Rhyolite forms intrusions, lava flows, and volcaniclastic deposits. The volcanic and sedimentary rocks probably formed in a series of extensional basins whose original size and shape is yet to be determined. At Grew Creek, gold-bearing chalcedony veinlets and associated argillic alteration are near rhyolite dykes. In the Glenlyon Area, quartz, chalcedony, and fluorite veins and associated silicification are in and near rhyolite dykes.

Organization: Government of Yukon | Gouvernement du Yukon