Post on 24-Jun-2020
Poster Session Abstracts
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AME Roundup 2017 Poster Session
Presentation Abstracts
Abstracts are listed alphabetically by first author. Student presenters are underlined.
Murray ALLAN Mineral Deposit Research Unit, University of British Columbia, British Columbia
Structural Controls on Gold‐bearing Veins of the Cariboo, Cassiar and Sheep Creek mining districts,
British Columbia
Co‐authors: David Rhys, Terence Harbort, Craig Hart and James Mortensen
Poster 30
Gold‐bearing quartz veins of the Cariboo and Sheep Creek mining districts of BC formed inboard (east) of the
suture between the Quesnellia arc terrane and North American passive margin sediments of Upper Proterozoic
to Lower Paleozoic age. Vein‐hosted gold mineralization in the Cassiar district is similarly situated east of the
Quesnellia margin, but is hosted mainly in metabasaltic rocks of the Slide Mountain terrane (Sylvester
allochthon), which structurally overlies platformal North American strata. In all three localities, penetrative
strain fabrics of the host rock sequence imply orogen‐normal shortening and simultaneous orogen‐parallel,
longitudinal extension. Quartz vein geometries and shear sense indicators are kinematically compatible with
coaxial progressive shortening under the same general stress regime responsible for earlier fold‐and‐thrust
style deformation. Gold mineralization of this style, examples of which occur along the entire strike length of
the BC Cordillera, thus signals the transition from collisional orogenesis in the Jurassic, to the onset of orogenic
collapse and extensive magmatism in the mid‐Cretaceous.
Joel ANGEN Mineral Deposit Research Unit, University of British Columbia, British Columbia
Improved Structural Framework for the Skeena Arch (West Central British Columbia)
Co‐authors: J.L. Nelson, M. Rahimi and C.J.R. Hart
Poster 29
The Skeena Arch is an east‐northeast trending belt of dominantly Jurassic volcanic rocks exposed across the
width of the Stikine terrane in central British Columbia. Mineral potential in the Skeena Arch is high, with the
majority of mineral occurrences interpreted as related to the Late Cretaceous Bulkley and Eocene Babine and
Nanika plutonic suites. Porphyry intrusions and associated hydrothermal fluids are often localized along
reactivated structures; therefore, understanding the structural framework of a region is advantageous when
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planning mineral exploration programs for porphyry and related deposit types. Little is known about the
structural framework of the Skeena Arch. We present preliminary results of targeted mapping, geochronology
and interpretation of new aeromagnetic data collected as part of the GeoscienceBC funded SeArch Phase 1
program. This study is aimed at refining the structural framework of the Skeena Arch and its relationship to
intrusive phases and mineralization. This study confirms the presence of east‐northeast trending compressional
structures parallel to the orientation of the Skeena Arch and south‐southeast trending extensional structures
perpendicular to it. Intrusions within the Skeena Arch occur parallel to both of these features.
Holly ARNOLD British Columbia Geological Survey, British Columbia
Using derived‐stereo imagery to map macro‐scale ice‐flow features
Co‐authors: A.S. Hickin and T. Ferbey
Poster 16
The majority of ice‐flow features (i.e. crag‐and‐tails, drumlins, drumlinoids, and flutes) previously mapped in
British Columbia are from mapping campaigns that used traditional stereoscopic aerial photography. Advances
in 3D digital technology have enabled the transition from hardcopy aerial photographic mapping and
interpretation to the digital environment. Derived‐stereo imagery provides the ability to use single frame
imagery types in traditional stereo mapping at a significantly less cost. Here we evaluate the efficacy of
stereoscopic aerial photography and two derived‐stereo imagery types (i.e. Satellite Pour l’Observation de la
Terre (SPOT) and orthomosaics) for mapping ice‐flow features in two areas of Northern British Columbia. Our
evaluation indicates that derived‐stereo orthomosaics provide the best value for cost to map ice‐flow features
for the ongoing ice‐flow indicator mapping in British Columbia by the British Columbia Geological Survey.
Jieun BAEK Pukyong National University, Republic of Korea
Uncertainty Analysis and Representation of Open Pit Optimization Results Considering Mineral
Price Volatility
Co‐author: Yosoon Choi
Poster 109
Determination of optimal open pit boundary is extremely important in planning an open pit mine. This study
proposes a new method to quantitatively represent the uncertainty existing in open pit optimization results
due to variations in mineral prices. After generating multiple mineral prices using Monte Carlo simulation with
data on past mineral prices, a probability model that represents the uncertainty was developed by integrating
multiple open pit optimization results derived from the mineral prices. The results of applying the proposed
method to the copper‐zinc deposits showed that significant uncertainty exists in open pit optimization results
due to the variation in copper prices. In addition, the study was able to quantify the probability that each block
that represents deposits is included within the open pit optimal boundary when copper and zinc prices increase
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or decrease from the current reference prices. Using these probabilities, reserves of the deposits were
estimated as a function of confidence level. When confidence level is set at 90% or higher, reserve was
estimated to be about 76,000 tonnes, and when confidence level was set at 50% or higher, reserve was
estimated to be about 2,550,000 tonnes. This suggests that the proposed method also has a potential as a tool
for classifying the estimation results of ore reserve based on confidence level.
Christopher BECKETT‐BROWN Laurentian University, Ontario
An investigation of tourmaline from Canadian porphyry deposits
Co‐authors: A.M. McDonald, M. Leybourne, J.B. Chapman and M.B. McClenaghan
Poster 49
Tourmaline minerals are common accessory phases in porphyry‐style deposits and have been proposed as
efficient indicators of porphyry‐style mineralisation. The tourmaline supergroup constitutes a large group of
alkali, borosilicate hydroxide minerals whose structural complexity permits the incorporation of a wide‐range
of elements including alkali and alkaline‐earth metals (Na, Ca, K, Rb), transition metals (Fe, Ni, Cr, Mn, Cu, Zn),
halogens (F, Cl, Br) and high field strength elements (REE, Hf, Zr, Ti, Nb, Ta). During precipitation from aqueous
solutions, many of these are incorporated with partition coefficients close to unity. Tourmaline has, therefore,
the potential to accurately record physiochemical changes of fluids throughout its crystallisation. We are
investigating the textural, chemical, and geological relationships of tourmaline among selected Canadian
porphyry (Cu‐Au, Cu‐Mo‐Au) deposits (e.g., Casino, YT; Schaft Creek, BC; Woodjam North, BC). Here we
describe three major textural types of tourmaline: 1) disseminated, 2) vein, and 3) breccia, all of which are
associated to varying degrees with Cu‐mineralisation. Tourmaline also exhibits variable growth histories,
including oscillatory and patchy zonation, that provide a record of evolving geologic processes. We are
employing a variety of techniques (e.g., scanning electron microscopy equipped with energy dispersive X‐ray
spectroscopy, laser ablation inductively coupled plasma mass spectrometry, and Raman spectroscopy) to
characterise and understand the development of tourmaline within mineralised porphyry systems. Defining
characteristics of tourmaline developing within mineralised porphyry systems will provide a baseline when
examining tourmaline during surficial exploration.
Rob BERMAN Geological Survey of Canada, Ontario
GEM‐2 progress in understanding the geological evolution and economic potential of the Thelon
tectonic zone
Co‐authors: W.J. Davis, M. Sanborn‐Barrie, M.W. McCurdy, I. McMartin, J.A. Craven, B. Roberts, R. Mitchell, J.B.
Whalen, L. Nadeau, B.E. Taylor, A. Camacho, S. Carr, E. Girard and P. Brouillette
Poster 71
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The GEM‐2 Thelon Tectonic Zone project is aimed at improving understanding of the geological evolution,
crustal architecture, and economic potential of a remote part of the Canadian Shield that lies between the
better‐known Slave and Rae cratons. Thematic bedrock mapping and supporting multidisciplinary studies
reveal Mesoarchean crust of Rae craton occurs ~40 km further east than previously interpreted, with its
western boundary marked by a >400‐km long belt of ca. 1.9 Ga peraluminous leucogranite. Whole‐rock oxygen
isotope data support leucogranite derivation from a passive margin or foredeep basin that was inverted and
melted during widespread, ca. 1.9 Ga upper‐amphibolite metamorphism. The orogenic core comprises three
belts of magnetite‐bearing, commonly orthopyroxene‐bearing, ca. 2.0 Ga metaplutonic rocks with convergent
margin geochemistry. The complexity of the orogenic core is underscored by the presence of ca. 2.6 Ga
plutonic rocks of unknown cratonic affinity, in tectonic contact with <2.07 Ga metapsammite (possibly as young
as interlayered 1.95 Ga quartz porphyry), which experienced ca. 1.81 Ga amphibolite‐facies metamorphism and
deformation. The west side of the orogen (eastern Slave craton) comprises a dioritic plutonic domain which
lacks distinctive Yellowknife Supergroup supracrustal rocks, has older Nd model ages than basement to the
Yellowknife Supergroup, and may represent a discrete, intervening crustal block. Garnet amphibolites in high
strain zones along its northwestern margin may record accretion of this crustal block. Stream sediment and till
samples collected during 2016 fieldwork are further defining several previously recognized regions with
elevated potential for base and precious metals.
Thomas BISSIG Mineral Deposit Research Unit, University of British Columbia, British Columbia
An Exploration Framework for Porphyry to Epithermal Transitions in the Toodoggone Mineral
District (94E)
Co‐authors: Farhad Bouzari and Craig J.R. Hart
Poster 35
The Toodoggone area in northeastern British Columbia hosts several precious metal‐rich mineral deposits and
occurrences classified as low or high‐sulfidation epithermal type mineralizations. Exploration activities thus far
were mostly focused on epithermal type of mineralization and on high‐grade ore‐zones. Past production at
Baker, Shasta and Lawyers is exclusively from veins previously classified as quartz‐adularia or low‐sulfidation
type. However, field observations together with short wave Infrared Spectroscopy (SWIR) and thin section
petrography strongly suggest that these mineralized zones are associated with andesitic to dacitic igneous
rocks, locally centered on porphyry stocks and correspond to porphyry type mineralization (e.g., Baker) and
intermediate‐sulfidation veins which either overprint porphyry‐style alteration (e.g., Shasta) or occur distal to
intense argillic alteration (Lawyers). At Baker, SWIR reveals that stockwork quartz veining is associated with
intense muscovite and illite alteration affecting quartz‐feldspar porphyry intrusions. Takla group basaltic rocks
are widely altered to chlorite‐sericite‐pyrite. More significantly, quartz‐magnetite‐chalcopyrite veins with
irregular boundaries within K‐feldspar altered rocks were observed in drill‐core drilled less than 200 m below
surface at Baker. Extensive quartz, sericite (illite), pyrite (largely oxidized) alteration, locally with chlorite occurs
at Black Gossan ca. 3 km east of Baker. Alteration assemblages including alunite, diaspore, dickite, kaolinite and
illite, typical for high‐sulfidation epithermal deposits, has been confirmed at Alunite Ridge, whereas
pyrophyllite occurs with alunite in the Creek‐zone at the Brenda prospect. However, intense residual quartz
alteration seems to be absent at Brenda and Alunite Ridge. Taking all observations together, the Toodoggone
epithermal mineral occurrences are considered part of porphyry mineral systems (sensu Sillitoe, 2010) and
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past‐producing veins are only a small part of such systems in the district. Consequently, significant exploration
potential remains particularly for porphyry‐style Cu‐Au mineralization.
Britt BLUEMEL REFLEX Geosciences, British Columbia
Adding Value to Regional Till Geochemical Data through Exploratory Data Analysis, TREK Project
Area, Central British Columbia (parts of NTS 093 B, C, F, G)
Co‐author: W.G. van Geffen
Poster 25
The most efficient use of resources in mineral exploration is to add value to existing data products. The utility
of existing geochemical data can be greatly improved by first order interpretation, because derivative data
products (which are common in geophysics) account for surficial processes. These derivative data products can
spur interest in areas that may have been otherwise overlooked.
Over the past 11 years, Geoscience BC has supported the continued collection and chemical analysis of
till geochemical samples in efforts to promote mineral exploration throughout British Columbia (BC). The TREK
(Targeting Resources for Exploration and Knowledge) Project was initiated in 2013 to generate new
information on BC's northern interior plateau region, an area which is highly prospective for mineral resources
and may also have some geothermal potential. However, the area is underexplored for these resources due to
overburden of variable thickness covering complicated and poorly understood bedrock geology. Across the
TREK Project area almost 3,000 samples were collected by the British Columbia Geological Survey, Geological
Survey of Canada and Geoscience BC. Samples from the BCGS and GSC campaigns were reanalysed as part of
the TREK Project (Jackaman et al., 2015), to ensure state‐of‐the‐art data quality.
All available till geochemical analyses in the TREK area were evaluated and assessed for comparability
and utility on an element by element basis. Data artefacts were visible between original survey areas, but these
effects were suitably handled throughout the following interpretation. The interpretation involved cluster
analysis to determine till provenance signatures, and these provenance groups were subsequently assessed for
multivariate outliers. Finally, areas of increased mineral potential based on ranked multi‐element anomalies
were identified using robust second order geochemical derivative products, and compared to known mineral
occurrences.
Matthew BODNAR Mineral Deposit Research Unit, University of British Columbia, British Columbia
Mapping chemical dispersion above a buried VMS in a till covered terrain, Lara VMS deposit,
Vancouver Island, Canada.
Co‐author: Peter Winterburn
Poster 27
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Landscape and surface material mapping with soil and vegetation sampling was undertaken at the Lara
polymetallic VMS deposit on Vancouver Island in order to identify processes that control trace element
dispersion of mineralization in the surface environment. Upper B horizon soil was collected along with follow‐
up Ah soil and western hemlock bark. Measurement of soil moisture, pH, redox potential, electrical
conductivity was completed at each sampling location. The research area is covered by till with erosional gullies
and related alluvial deposits. A compilation of drill hole data has shown that till cover ranges between 6 ‐ 12 m
with thickness increasing to 15 – 22 m over a fault system hosting the Zn‐Pb‐Cu sulphide mineralization. Results
of B horizon soil chemistry demonstrate an anomalous trend of Cu, Zn exists in soil over mineralization.
Continued research includes till clast analysis, soil hydrocarbon data, self‐potential and non‐traditional stable
isotope analysis of Cu and Zn. The results of this work will generate a model of trace element dispersion over
the Lara VMS deposit that integrates bedrock geology, landscape evolution and soil development to identify
processes resulting in genuine and false anomalies.
Farhad BOUZARI Mineral Deposit Research Unit, University of British Columbia, British Columbia
Assessing BC Porphyry Fertility using Zircons
Co‐authors: Craig Hart and Thomas Bissig
Poster 36
Distinguishing metal fertile from barren plutons is a significant advantage for exploration geologists seeking
porphyry copper deposits particularly in British Columbia where many porphyry systems occur within or
around the edges of large batholiths. Zircon is a geochemically‐robust mineral and records orthomagmatic
compositions that influence formation of porphyry copper deposits. Zircon samples from Highland Valley,
Woodjam, Gibraltar, Lorraine, Kemess and several other deposits in BC are characterized texturally and
analyzed using electron‐probe and LA‐ICP‐MS. Preliminary results of Ti‐in‐zircon temperature from Takomkane
batholith and Woodjam district shows that zircons from the Boss Creek and Schoolhouse Lake plutons have
variable temperatures from 950°C to below 700°C, whereas the older Spout Lake pluton has temperatures near
800°C. Zircons from the mineralized Woodjam Creek granodiorite have temperatures of 750° to 650°C.
Chemical compositions of zircons indicate that the unmineralized Boss Creek unit has a more pronounced
europium anomaly (EuN/EuN* < 0.35) compared to the other rock suites. Zircons from the mineralized
Woodjam Creek unit have relatively small negative europium anomalies (mostly > 0.35). The younger phases of
batholith, Schoolhouse Lake and the quartz feldspar porphyry unit, both similar to Woodjam Creek, display
EuN/EuN* < 0.35 but these phases have a larger range of EuN/EuN*. These results indicate that zircon
crystallization in porphyry fertile plutons occurred in near‐eutectic conditions close to the solidus of hydrous
granite. Moreover, small negative europium anomalies in zircons suggest high water contents and late
magmatic oxidation resulting in the loss of SO2‐rich magmatic‐hydrothermal ore fluids during late‐stage
crystallization of granites.
Jim BRITTON Ministry of Energy and Mines, British Columbia
2016 Exploration and Mining Highlights, South‐Central Region, BC
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Poster 20
Poster will present visual highlights of mineral exploration activities and mining developments in BC's South‐
Central Region (formerly Thompson‐Okanagan‐Cariboo Region) for the 2016 calendar year.
Katelynn BROWN University of Saskatchewan, Saskatchewan
Heavy mineral compositions in Saskatchewan till: classification and constraints on source, with a
focus on garnets
Co‐author: Kevin Ansdell
Poster 90
Glacial sediments of varying thickness cover much of Saskatchewan’s landscape, creating significant challenges
in mineral exploration within the underlying rocks. However, the scouring of bedrock by glacier ice often leads
to the entrainment and transport of rock debris, which is later deposited as till. Within this till, there may exist
heavy minerals indicative of mineral deposits previously eroded by the glacier. If dispersal trains of these
indicator minerals can be identified, they can be traced back to their original source based on an understanding
of historical ice flow directions.
This study investigates a suite of heavy minerals, with a focus on garnets and ilmenites, recovered from
till samples of an active diamond exploration project in Saskatchewan. The minerals have been analyzed using
the electron microprobe to determine their composition, and to identify mineral inclusions, chemical zonation,
and internal textures. Preliminary results indicate that the garnets are not zoned and are dominated by the
pyrope component, with up to 12 wt. % Cr2O3. Evidence suggests that these garnets may be derived from
metasomatized lithospheric mantle, similar to those of the Fort à la Corne kimberlites located on the Sask
Craton. Some of the ilmenites, which preserve complex internal textures, are Mg‐rich and may be derived from
a similar source. The mantle‐derived garnets will be further studied in order to shed light on the pressure‐
temperature conditions and mantle composition at the time of their formation, and to determine if these
conditions are appropriate for the formation of diamondiferous kimberlites.
Aaron BUSTARD British Columbia Geological Survey, British Columbia
Till geochemistry of the Pendleton Bay map area (NTS 93K/12), British Columbia
Co‐authors: T. Ferbey, and V.M. Levson
Poster 15
Regional till geochemical sampling in the Pendelton Bay area (NTS mapsheet 93K/12) has successfully detected
dispersal from known porphyry Cu±Mo±Au mineralization at the Fort showing (MINFILE 93K 093) and identified
three new areas of geochemical interest. Situated 30 km southwest of the past producing porphyry Cu±Mo±Au
Bell and Granisle mines, the Pendleton Bay area has potential to host new porphyry Cu±Mo±Au mineralization
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but access to the area is limited and glacial sediment cover is extensive. To better assess mineral potential
here, 182 subglacial till samples were collected by the British Columbia Geological Survey in 1998 for
geochemical analysis of the <63 µm size fraction by inductively coupled plasma emission spectroscopy (ICP‐ES)
and instrumental neutron activation analysis (INAA). Ice‐flow features indicate that glacial dispersal was
predominantly towards the east and southeast. Sampling near the Fort showing has identified that the
maximum Cu value (522 ppm Cu) occurs 700 m northeast of the main showing, and anomalous values above
the 90th percentile (60 ppm Cu) continue for approximately 2 km down ice (southeast). The Mo footprint in till
at the Fort showing is smaller, with the maximum value (29 ppm Mo) occurring 300 m to the northeast, and
concentrations falling to near detection limit 800 m to the east. Three additional areas have been identified
with anomalous values of Cu (up to 167 ppm), Cr (up to 263 ppm), and Ni (up to 101 ppm). The identified
geochemical anomalies provide a starting point for future exploration work in the area.
Michelle CAMPBELL Oregon State University, USA
Magmatic and Hydrothermal Evolution of the Kerr‐Sulphurets‐Mitchell porphyry Cu‐Au district,
British Columbia
Co‐author: John H. Dilles
Poster 48
The Kerr‐Sulphurets‐Mitchell (KSM) porphyry Cu‐Au‐Mo‐Ag district, located in northwestern British Columbia,
hosts one of the world’s largest undeveloped reserves of copper and gold. The KSM district features four
distinct ore bodies: Kerr, Sulphurets, Mitchell and Iron Cap. The four deposits are contemporaneous, featuring
predominantly hypogene mineralization centered on Early Jurassic intrusions. Nonetheless, each of the four
deposits displays a unique combination of important attributes, including the nature of the syn‐mineral
intrusions, overall Cu/Au ratio, deposit morphology, and proportion of mineralization hosted within wallrock.
We present an overview of the principal igneous phases and styles of hydrothermal alteration present at KSM,
revealing new insights into the magmatic evolution of the district.
A notable characteristic of the KSM district porphyry deposits is their enrichment in gold, which is
commonly associated, in British Columbia, with alkalic porphyry systems. The Kerr, Mitchell and Iron Cap
deposits, however, display the characteristics of typical calc‐alkaline porphyry deposits: early central potassic
alteration with abundant quartz veining and lateral propylitic alteration cut by extensive sericitic alteration
with high pyrite contents. The nature of the fault‐dismembered and possibly truncated Sulphurets deposit,
primarily hosted by sedimentary wallrock, is somewhat more cryptic. Nevertheless, weakly mineralized alkalic
intrusions, roughly coeval with the calc‐alkaline intrusions, are also found within the district – a feature which
has been observed at other large gold‐enriched copper porphyry deposits (e.g., the Pebble and Bingham
deposits). Additional gold enrichment factors, including the emplacement of the KSM deposits on relatively
thin crust and at shallow depths, will also be examined.
Jamie CAMPO Western Washington University, USA
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Cathodoluminescence and trace elements in quartz from low sulfidation epithermal ore deposits;
implications for ore genesis
Co‐authors: Brian Rusk, Mark Simpson and Heather Lowers
Poster 42
We analyzed quartz veins from twelve low‐sulfidation epithermal (LSE) deposits in New Zealand, Australia,
Japan, Canada, and the United States. Quartz textures were imaged in both monochrome and color SEM‐CL
with trace elements measured by LA‐ICP‐MS and EPMA. Here we correlate the relationship between trace
elements and CL textures to better constrain the complex vein history and physio‐chemical conditions of
epithermal vein genesis.
Quartz textures reflect the steep gradients in composition, pH, fS2, and fO2 at the boiling zone. Rapidly
changing physio‐chemical conditions are inferred by the sharp contrasts in CL character in adjacent quartz
bands. Quartz SEM‐CL textures include euhedral zoned crystals, homogenous bands, plumose textures,
chalcedonic banding, mossy aggregates, CL dark fractures, microbrecciation, cockade textures, and bladed
carbonate replacements. Boiling indicators appear as spheroidal growths and bladed quartz after calcite.
Trace elements correlated to CL intensity in epithermal quartz include Al, Li, Na, K, Ga, Ge, and Sb.
Other trace elements include B, Be, Ca, Fe, Mn, P, and As. Aluminum typically ranges from 10s‐100s of ppm or
1000‐4000 ppm. Lithium correlates strongly with Al, ranging from 10s of ppm or 100‐500 ppm. Gallium, Ge, and
Ti are typically <2 ppm. Antimony ranges from 10‐80 ppm. Some low Al quartz contains elevated Ga and Sb
concentrations, reaching up to 20 ppm or 300 ppm respectively. Shifts in CL character correlate directly with
trace element concentrations, but no consistent relationship applies across all deposits. Electron microprobe
results suggest Na and K correlate with Al‐rich CL growth zones.
Samuel CANTOR University of British Columbia, British Columbia
Stable isotopes as an exploration tool: tracking cryptic alteration surrounding the Iscaycruz Zn (Pb‐
Cu‐Ag) skarn‐CRD deposit, Central Peru
Co‐authors: Craig Hart, Greg Dipple, Abraham Escalante, James Mortensen and Russ Algar
Poster 101
The Iscaycruz Zn‐(Pb‐Cu‐Ag) skarn‐carbonate replacement deposit (CRD) is located within a sequence of lower
Cretaceous‐aged, layered carbonate and siliciclastic rocks in central Peru. The deposit is located on the
western flank of a tightly compressed anticline (Escalante and Hart, 2011), within a larger northwest‐trending
thrust‐fold belt in the Western Peruvian Cordillera (Wilson, 1963). Proximal stable isotope haloes have been
identified surrounding the Antamina Zn‐Cu skarn, Uchucchacua Ag‐base metal vein, and Iscaycruz Zn‐(Pb‐Cu‐
Ag) skarn‐CRD in central Peru. Studies analyzing stable isotopes around mineral deposits observed consistent
alteration haloes of carbonate rocks with relatively depleted ẟ18O values proximal to the center of
mineralization, as well as areas of higher degrees of fluid/rock interaction (Barker 2013). Prior work in the
Iscaycruz district identified several stable isotope anomalies; however, an investigation between these
anomalies and various stratigraphic units, orebodies, or sulfide accumulations has not been conducted. The
primary goal of this study is to integrate visible and cryptic alteration around a known ore body and utilize the
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resulting identified relationships as an exploration tool for regional targets. The initial sampling survey
collected representative samples from contacts, structural intersections, and mineralized zones to assess the
interactions between fluids and carbonate host rocks. The second sampling survey focused on regional
sampling, Pb‐isotopes, and prospective contacts north of the Santa Este pit. The two surveys accumulated
~1,600 samples for stable isotope analysis from surface and subsurface locations around the Iscaycruz deposit,
and from surface locations in the Palpas region located 12 km west of Mina Iscaycruz.
Sébastien CASTONGUAY Geological Survey of Canada, Quebec
The Gold project of the Targeted Geoscience Initiative (TGI‐5; 2015‐2020): Main objectives and
ongoing research
Co‐authors: Patrick Mercier‐Langevin, Benoît Dubé, Christopher J.M. Lawley, Vicki McNicoll, Nicolas Pinet,
Wouter Bleeker, William J. Davis, Simon Jackson and Valérie Bécu
Poster 69
The Targeted Geoscience Initiative (TGI) is a collaborative federal‐provincial‐academia‐industry research
program led by NRCan that aims at providing new knowledge to improve effective targeting of buried mineral
deposits.
The overarching objective of the TGI‐5 Gold project is to better define the mechanisms that control the
heterogeneous distribution of gold resources through space and time and to tackle some of the crucial issues in
our understanding of ore‐forming processes at the ore system scale. Our approach requires a multi‐scale
(craton to ore zone) and multidisciplinary approach. Two complementary subprojects have been defined: 1)
System controls on gold through space and time (source and trap), and 2) Tectonic influences on the formation
and distribution of gold deposits (tectonic drivers and conduits). Each subproject is divided into a series of
thematic and/or regional research activities.
Subproject 1 aims at assessing and synthesising the multi‐scale geologic characteristics of gold
mineralization in selected well‐endowed regions, and at undertaking comparative targeted studies in “less
fertile” environments. Emphasis is put on district‐scale features, which represent a priority and a geological
challenge for the mineral exploration industry. Subproject 2 consists of an analysis of the geometry and
kinematic evolution of major ore‐associated structures in selected districts and their relationships to different
types of gold deposits.
Most planned research activities were initiated in 2016, including several graduate thesis projects, and
already have highlighted some recurring and site‐specific characteristics that will be further documented and
interpreted in the coming years to provide new and revised models for gold exploration in Canada.
Hannah CAVALLIN Western University, Ontario
Gold Mineralization at the Monument Bay Deposit, Stull Lake Greenstone Belt, Manitoba
Co‐authors: C. Bajwa, M. Metcalf, T. Twomey, G. Kuntz, C. Venturi, C. O'Shea and N.R. Banerjee
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Poster 44
Yamana Gold Inc.’s Monument Bay Project within the Stull Lake Greenstone Belt in northeastern Manitoba
hosts economically promising Archean shear‐hosted gold deposits. The project is comprised of three separate
deposits: The Twin Lakes, the Mid‐East, and the AZ deposits, which lie within the Oxford Stull Domain of the
Western Superior Province. The east‐west trending granite‐greenstone belt is exposed across northeastern
Manitoba and northwestern Ontario, and records a complex history of magmatism, sedimentation, and
deformation associated with periods of subduction and continent‐continent collision. Gold mineralization
occurs in 1) smoky quartz veins that are locally mineralized, 2) quartz‐carbonate‐tourmaline veins, and 3)
quartz‐carbonate‐albite‐scheelite veins, which represent the main mineralization type at the Twin Lakes
deposit. Quartz‐feldspar porphyry dykes/sills and surrounding rocks are the dominant host rocks for
mineralization within east trending, steeply north dipping shear zones. The current study will examine the
associations and controls on gold mineralization at Monument Bay and elucidate relative timing relationships,
alteration types, and trace element correlations, such as arsenic and tungsten that could be used for vectors to
gold mineralization. This will be accomplished using petrography, existing ICP data, X‐ray diffraction (XRD), and
electron microprobe analysis (EPMA). The goal is to provide a foundation for further study and investigation of
the Twin Lakes, AZ, and Mid‐East deposits that can be used to better understand the formation of these
deposits and provide geochemical exploration vectors to help future exploration in the region.
Erika CAYER Mineral Deposit Research Unit, University of British Columbia, British Columbia
Direct Detection of Drift‐Concealed Kimberlites Using Surface Geochemistry and Landscape
Evolution in the Northwest Territories, Canada
Co‐authors: Peter Winterburn and Barrett Elliott
Poster 91
The DO‐18 kimberlite is buried beneath 5‐20 meters of till deposited by the Laurentide ice sheet. 150 soil
samples from the oxidized upper B‐horizon in a detailed grid crossing the kimberlite were taken to assess the
potential of surface geochemical techniques in conjunction with surface materials mapping and landscape
evolution modelling to detect the presence of a concealed kimberlite. Samples were screened to ‐180 microns,
and analysed by multi‐element ICP‐MS following 4‐acid, aqua‐regia and deionized water extractions, as well as
fp‐XRF.
Geochemical data is subject to geomorphological processes. The northern half of the grid comprises till
with numerous frost boils. The southern, topographically low region is dominated by fluvial deposits. Results
from the 4‐acid and aqua regia extraction show a dispersion of Nb, Ni, Mg, and Cr from directly above the
northern part of the kimberlite to the edge of the sampling grid, approximately 500 metres to the northwest,
following glacial dispersion. fp‐XRF data repeats the pattern in all elements except Mg, where the
concentrations are too low for reliable detection. Sequential leach on selected samples was undertaken to
identify which phases within the soil are host to the aforementioned anomalous elements. Surficial mapping
included soil type, topographic variation, landforms, environment and vegetation, giving insight to the surface
controls on the geochemistry.
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Clastic dispersion down ice of the kimberlite is hypothesized to have generated the observed
geochemical anomaly. The southern part of the area is considered to have been inundated with water, diluting
geochemical responses.
John CHAPMAN Geological Survey of Canada, British Columbia
Picrite Possibly Pinpoints Porphyry Prospectivity?
Co‐author: Dejan Milidragovic
Poster 68
From the early days of geological exploration within the Canadian Cordillera, picritic igneous rocks have been
noted as a very minor but widespread component of its Mesozoic volcanic sequences. G.M. Dawson described
picrite bodies in the vicinity of the Guichon Creek and Iron Mask batholiths in 1895, and further work in the
century since has extended the known range of similar rocks along the lengths of both Quesnel and Stikine
terranes. Geodynamic models for porphyry ore‐formation within the Cordillera have suggested this picritic
magmatism may have been caused by abnormal heat flow into the arc mantle wedge, possibly a result of
tearing or break‐off of the subducted oceanic slab. However, recent assessments of the formation
temperatures of picrite bodies proximal to the Schaft Creek Cu‐Mo deposit have shown that these were in
‘normal’ basaltic ranges (<1300°C), with enhanced partial melting likely having been caused not by excess heat
but by volatile components within the melting region. Whether these volatile concentrations are abnormal
within arc magmatism, or whether it is the eruption of otherwise commonplace primary arc melts that is
unusual, remain unanswered questions. In addition, the spatial relationship between picritic volcanism and
porphyry ore deposits remains striking, but it is unclear whether this reflects a true causal link or simply the
effect of sampling or confirmation bias. This poster will examine that relationship in the context of present data
for the Cordillera, as well as other known arc picrite occurrences worldwide.
Robert CHAPMAN University of Leeds, UK
Trace Element Quantification in Gold by Laser Ablation Inductively Coupled Plasma Mass
Spectrometry
Co‐authors: David A. Banks, Carl‐Spence Jones, Olga Borovinskaya and Matthew Grimshaw
Poster 34
Analyses of natural gold grains has largely been restricted to the major components, Au, Ag, Cu, Hg from
electron microprobe analysis (EMPA) due to the relatively high detection limits for minor elements. LA‐
ICP(quadrupole)‐MS has sub‐ppm detection limits for most elements in gold, but by comparison with EMPA is
both destructive and penetrates the gold to much greater depth. We have analysed natural gold grains for Si,
Al, S, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Y, Nb, Mo, Rh, Pd, Ag, Cd, In, Sn, Sb, Te, La, W, Pt, Au, Hg,
Pb, Bi, Th, U to assess which are present in sufficient concentration to form a basis for the discrimination of
13
gold from different localities and different styles of mineralization. Quantitative analyses were achieved by
combining a number of certified standards, NIST 610 (silicate glass), AuRM2 (London Bullion Gold Standard),
USGS Mass‐1 (synthetic sulphide standard) and NIST 481 (gold silver wires) as no one standard exists with
concentrations comparable to those in natural gold and contains all these possible elements. In some instances
element distribution may not always be homogeneous and we have mapped these using LA‐ICP (time of flight)
MS at a scale of 10 microns or less. Some elements show grain boundary or crystal structure controlled
variability at concentrations much lower than previously seen in EMPS analyses. The combination of spot
analysis and multi‐element mapping reveals much more detail than previously available and is likely to allow
discrimination between natural occurrences.
Rachel CHOUINARD University of British Columbia, British Columbia
Surficial Geochemical Footprint of Buried Porphyry Cu‐Mo Mineralization at Highland Valley
Copper: Project Update
Co‐authors: P.A. Winterburn, M. Ross and R.G. Lee
Poster 61
The research project is part of the Porphyry Cu Subproject of the National Sciences and Engineering Research
Council (NSERC) and Canadian Mining Innovation Council’s (CMIC) Mineral Exploration Footprints project. This
subproject aims to quantify and identify the footprint of porphyry Cu‐Mo mineralization at the Highland Valley
Copper (HVC) operation through a multidisciplinary, integrated approach. Teck Resources Limited (“Teck”) has
a 100% interest in HVC which is located in south‐central BC, 15 km west of the municipality of Logan Lake, and
consists of five known porphyry‐style Cu‐Mo mineralized bodies. These clusters include: 1) the active producing
Valley, Lornex and Highmont pits; 2) the past producing Bethlehem deposit; and 3) the buried J.A. deposit, all
of which are centrally located within the Guichon Creek batholith. The J.A. and Highmont South targets
comprise two mineralized areas that are both undeveloped and buried under variable thicknesses of glacial and
preglacial sedimentary cover. Surficial geochemical studies at these two buried targets aim to fully characterize
mineralogical and chemical changes that manifest themselves in the surficial environment after glacial
dispersal and soil development over mineralized bedrock. The research will help develop surficial geochemical
exploration models that can be applied to the search for other buried Cu‐(Mo) porphyry mineralization. This
poster provides an update on the progress of the project, which is expected to be complete by August 2017.
Anastasia COMTOIS‐POISSANT University of Regina, Saskatchewan
Petrogenesis and Geochemistry of Mafic Granulites from the Upper‐Deck of the Tantato Domain,
Northern Saskatchewan, Canada
Co‐authors: T. Raharimahefa and C. Normand
Poster 89
14
The Tantato Domain, or the East Athabasca Mylonite Triangle of Northern Saskatchewan, is one of three
“lozenges” of mylonitized lower Archean crust, of which, extend into the Northwest Territories, and are located
between the Grease River Shear Zone and the Snowbird Tectonic Zone. The Tantato Domain is commonly
divided into two subdomains based on structural and metamorphic characteristics, referred to by authors as
the Upper Deck and the Lower Deck. Each subdomain is characterized by a different suite of rocks, with the
Upper Deck being composed of extensive mafic intrusions emplaced in psammopelitic gneisses, and meta‐
tonalities at approximately 2.6 Ga. These mafic intrusions have since undergone predominately granulite facies
metamorphism and therefore are referred to by many authors as “mafic granulites” although small lenses of
mafic eclogites can be found in the northern half of the Upper Deck, with the metamorphic grade decreasing to
the south to mafic amphibolites can also be found. These mafic intrusions have been of economic interest as
they have been found to host to Nickle‐Copper sulphide deposits in the Axis Lake area, however, very little its
understood of the origin of these rocks. This poster will summarize the preliminary geochemistry analysis done
on these mafic granulites. The goal of the geochemical analysis its to help understand more about the
petrogenesis of the magma, including the source of magmas, where in the crust the magma was emplaced and
under what tectonic setting.
Fred COOK Salt Spring Imaging, British Columbia
Combining Geological, Seismic Reflection and Magnetotelluric Data in the Purcell Anticlinorium, SE
British Columbia
Poster 21
Combining geological data, seismic reflection data and magnetotelluric (MT) data in southeastern British
Columbia can target concentrations of sulphide mineralization in the subsurface. Existing MT data are being
reprocessed with two‐dimensional (2D) inversions where possible, and the results are combined with
reprocessed seismic reflection profiles and drill hole information. Seismic reflection data acquired for
hydrocarbon exploration were initially reprocessed for large‐scale regional studies; however, by focusing on
the near‐surface data, they provide a unique view of the Purcell basin that is not available with any other
geological or geophysical data set. A deep (3.477 km) exploration drill hole was drilled by Duncan Energy in
1985 and provides definitive correlations of seismic reflections to stratigraphic horizons along a number of
seismic profiles. Thus, the seismic data and drill holes allow detailed mapping of structural and stratigraphic
variations, while the MT data help to characterize the electrical properties, and thus perhaps the presence or
not of metals, at different stratigraphic levels.
Yao CUI British Columbia Geological Survey, British Columbia
Digital Geology: progress in data integration
Co‐authors: Deanna Miller and Larry Diakow
Poster 11
15
The British Columbia Geological Survey (BCGS) has developed a ‘geospatial frame data’ (GFD) model to simplify
the compilation, update, edit, and integration of geological maps into a province‐wide spatial database for
digital geology. The GFD model only consists of centroids (describing map units) and lines (defining geological
boundaries) to store, edit, revise, and integrate geological maps. Bedrock polygons are not part of the GFD but
are generated from the GFD for the finished maps. Using the GFD model, maps are integrated with a ‘checking‐
out’ and ‘anchoring’ mechanism to eliminate map boundary issues in edge matching. The GFD model is
implemented in a PostgreSQL/PostGIS database at BCGS, making it possible to handle large volumes of data,
and permit multiple users to perform concurrent operations on the same GFD base. As part of the spatial
database management system, database applications automate checking‐out, anchoring, integration, and
creation of bedrock polygons. These applications not only simplify the integration process, but also streamline
rules‐driven data quality checks, content standardization, change audits, map legend updates, and production
of custom maps for delivery via web services. Currently, BCGS is using the GFD model to facilitate regional
compilations and map integration, including south Nicola, Chilcotin and Bonaparte, Atlin, Dease Lake, Iskut, and
Bowser basin areas. The bedrock legend at the provincial scale also has a new colour scheme to highlight major
geological units.
Yao CUI British Columbia Geological Survey, British Columbia
Up to Speed on MapPlace 2
Co‐authors: Steven Zhao, Larry Jones, Gabe Fortin and Sarah Meredith‐Jones
Poster 10
The British Columbia Geological Survey (BCGS) creates, delivers, and archives geoscience data to help industry,
research agencies, and the general public make decisions related to the Earth sciences. Since 1995, MapPlace
has been providing web map services to help clients browse, visualize, and analyze an array of geoscience and
mineral resource data, including geology, mineral occurrences, regional geochemical survey, assessment
reports, geophysical survey, and mineral tenures. BCGS has recently revamped its web map services by
developing MapPlace 2, with a new interface and much improved functionality and performance. MapPlace 2
beta is available on the BCGS website for the public to use. MapPlace 2 is designed for use by anyone
interested in British Columbia geoscience, including the mineral industry, resource planners, public safety
agencies, communities, First Nations, government, and research organizations. MapPlace 2 has a simple and
intuitive interface that is easy to use, requires no plug‐ins, and works in most web browsers. MapPlace 2 differs
from other web services: it allows visualizing and querying province‐wide geoscience data at exceptional speed,
and provides advanced custom applications to search, analyze, report, and download these data. The power of
MapPlace 2 derives from databases that talk to each other, enabling users to conduct queries and generate
custom results by connecting many data sources. MapPlace 2 embraces the most appropriate open‐source
software for rendering maps, integrating databases, and developing web applications. BCGS will continue to
improve MapPlace 2 with advanced applications and access to more databases.
Victor DE BRONAC DE VAZELHES Université Laval, Quebec
16
Quaternary mapping and till geochemical analysis: glacial dispersal of a gold deposit in the Amaruq
area, Nunavut
Co‐authors: Nicolas Boulianne‐Verschelden, Georges Beaudoin, Isabelle McMartin, Olivier Côté‐Mantha and
Marjorie Simard
Poster 99
Understanding remobilization of a deposit by glacial processes is challenging, especially in polyphase glacial
flow areas, highlighting the need to map and interpret glacial deposits in detail. The Amaruq deposit (Nunavut),
owned by Agnico Eagle Mines Ltd., is located in the Rae Province of the Churchill craton, within the Woodburn
Lake greenstone belt. The mineralization is interpreted as a stratiform and vein‐type iron formation‐hosted
gold deposit. During the last Wisconsin glaciation, it was eroded by the Laurentide Ice Sheet which covered the
Archaean basement with till and remodeled the bedrock surface. Amaruq offers an excellent case study,
because of the association of multiple glacial landforms, variable till thickness, lack of significant vegetation
cover, and mineralized structures perpendicular to the main regional ice flow direction.
Four sets of ice flow indicators are recognized. The oldest oriented towards the NNW (345°) is responsible for
most of the glacial moulding of the landscape. The second and third are oriented respectively at 325° and 308°.
The final ice flow is oriented toward a nearby esker.
The interpretation of a detailed scale till geochemical dataset (100 m spacing) using Principal
Component Analysis (PCA) shows an association between gold and arsenic, silver, cobalt, nickel and copper in
the first component (45 % variance). Kriging of PCA scores in this component at each till sampling point shows a
NNW dispersal pattern in the gold mineralization signature. An area of thick till north of the Whale Tail zone
suggests the deposit anomaly reaches the till surface approximately 1,5 km from the outcropping
mineralization, now beneath a lake.
Kristin ENS University of Saskatchewan, Saskatchewan
Isotopic and geochemical investigation of the igneous intrusions of the Little Rocky Mountain
region of Montana
Co‐authors: Matthew Tsui, Bruce Eglington and Camille Partin
Poster 58
The Little Rocky Mountains region of Montana, near the town of Zortman and the old Zortman‐Landusky gold
mine, preserves exposures of Precambrian basement and overlying Palaeozoic to Mesozoic sediments. These
sediments are intruded by lamprophyre dykes and a series of granite and syenite porphyries. Previous K‐Ar
dating suggests that the porphyries are Eocene in age although no high‐temperature mineral phases such as
zircon have been dated. The Little Rocky Mountains exposures are located near the northern margin of the
Wyoming Craton, close to the boundary of the Great Falls tectonic zone. Both ultramafic and felsic intrusive
lithologies occur in close proximity. Their occurrence near the crustal to lithospheric contact may reflect deep‐
penetrating structures, possibly associated with Eocene reactivation well inboard of the coeval volcanic arc
igneous activity which occurs further west in Washington and Oregon states and in British Columbia. Whole‐
rock Rb‐Sr, Sm‐Nd and Pb‐Pb isotope analyses, lithogeochemistry and zircon U‐Pb and Lu‐Hf isotope analyses
17
are being conducted to better constrain the timing and nature of the igneous activity and the
crustal/lithospheric source regions involved.
Rachel GAVIN University of British Columbia, British Columbia
Field Relationships and Structure of Silver‐rich Veins, Cariboo Gold District, British Columbia
Co‐authors: Murray Allan, Terence Harbort and Craig Hart
Poster 46
The Cariboo Gold District (CGD) in east‐central British Columbia is a hotbed for gold exploration and
production. The Cariboo gold rush began in the late 1850s with the discovery of placer‐gold in streams near
Likely and the Wells‐Barkerville area, and lode‐gold was discovered not long after. To date, the CGD has yielded
an estimated 118 ‐ 134 tonnes of gold (Levson and Giles, 1993). Although structural controls appear to be
similar throughout the CGD, not all mineralized veins are gold‐bearing; a cluster of argentiferous quartz veins,
located 23 km southeast of Barkerville Gold Mines’ Cow Mountain deposit, are dominated by silver, copper,
lead, zinc and tungsten minerals with little to no gold mineralization. Relatively fresh lamprophyre dikes, some
containing xenoliths of quartz vein fragments, intrude close to and apparently cross‐cut these veins. Silver
Mine, Penny Creek, and Cariboo Hudson are examples of such occurrences. Silver Mine, a past‐producer and
the most prominent vein in this cluster, is the focal point of this study. Detail maps and field observations
produced in the summer of 2016 are presented, as well as preliminary results from petrographic and structural
analysis.
Janelle GHERASIM Utah Valley University, USA
Geochemical and Sociological Study of Backyard Wells and Gardens in Utah Valley, Utah
Co‐authors: Sterling Roberts, Skyler Tulley, Brennan Christensen, Anthony Bradford, Colby Oliverson, Joshua
Mcneff, Jarrett Nichols, Jake Sorensen, Steven H. Emerman, Alexander T. Simon and Eddy Cadet
Poster 102
Ferreira (2013) documented elevated concentrations of As and heavy metals in rivers that flow westward
across the Wasatch Range and heavily‐populated Utah Valley, Utah, to drain into Utah Lake, which is consistent
with the history of unregulated mining in the watershed of Utah Lake. In Utah Valley it is not uncommon for
urban residents to dig and maintain shallow (< 10 m) wells in their backyards, although the practice is illegal in
Utah and unusual in urban areas outside of developing countries. Since the rivers in Utah Valley are losing
streams, the question arose as to the levels of As and heavy metals in these shallow wells. Chemical analysis of
107 backyard wells thus far has shown that EPA Drinking Water Standards are not met for Mn, As, Cd, Fe, Cu,
Pb, and nitrate in 18.7%, 15.9%, 6.5%, 6.5%, 0.9%, 0.9%, and 0.9% of wells. According to a preliminary analysis
of 20 interviews carried out, wells are dug and maintained for emergency planning and for watering lawns and
livestock and are conservative in terms of their social, political and religious attitudes. In fact, owners of
backyard wells are no different than the mainstream of Utah culture, which suggests that backyard wells may
18
be very common throughout the state. These findings raise the possibility that a state water policy that is
backed by the public ought to include the promotion and legalization of safe water supply at the household
level.
Rohanna GIBSON British Columbia Geological Survey, British Columbia
Syncollisional Middle Jurassic volcanism and porphyry‐style alteration in Stikinia: a new
metallogenic epoch in northwestern British Columbia?
Co‐author: Bram van Straaten
Poster 4
Geologic mapping and geochronological studies on the northeastern margin of Stikinia identified an unusual
late Early to Middle Jurassic volcanic succession that hosts porphyry‐ and epithermal‐style mineralization. We
assign it to the recently defined Horn Mountain Formation. The sequence is coeval with accretion of Stikinia
and Quesnellia; volcanic rocks of this age are rare in northern Stikinia.
The Horn Mountain Formation (ca. 5.4 km thick, Toarcian to Bajocian) consists of lower subaqueous
mafic volcanic breccia units, an overlying subaerial mafic flow, volcanic breccia and tuff unit, and an
unconformably overlying mafic volcanic flow unit. It gradationally overlies sedimentary rocks of the Spatsizi
Formation (up to 1 km thick, late Pliensbachian to Toarcian). The Horn Mountain Formation is cut by the Three
Sisters pluton (ca 173‐169 Ma) and unconformably overlain by sedimentary rocks of the Bowser Lake Group
(Bajocian). Folded Takwahoni Formation (Pliensbachian) sedimentary rocks structurally overlie the Horn
Mountain Formation in the hanging wall of the south‐verging Kehlechoa thrust fault. The Snowdrift Creek
pluton (Late Jurassic) cuts the Kehlechoa fault and constrains movement to ca 170‐160 Ma.
The Horn Mountain Formation hosts two early‐stage porphyry projects. At Tanzilla, advanced argillic
and porphyry‐style alteration hosts anomalous Cu‐Mo. The McBride Cu‐Au showing has widespread quartz‐
sericite‐pyrite and local potassic alteration. We extended the advanced argillic alteration at Tanzilla for at least
17 km along an unconformity within the upper Horn Mountain Formation. Syncollisional late Early to Middle
Jurassic magmatism and volcanism represent a potential new metallogenic epoch for the Canadian cordillera.
Martyn GOLDING Geological Survey of Canada, British Columbia
Conodonts from the Cache Creek and Stikine terranes in northern British Columbia and southern
Yukon
Co‐authors: A. Zagorevski and M.J. Orchard
Poster 73
As part of the geological framework of ancient oceanic crust activity of the GEM‐2 Cordillera project, more than
500 archive conodont samples housed at the Geological Survey of Canada have been re‐examined. These
samples have been collected over the past 40 years by numerous GSC mappers and external collaborators, and
19
define a unique dataset that has previously only been available from largely unpublished paleontological
reports. The current contribution presents a tabulation of all of the collections containing identified conodonts
from the northern parts of the Stikine and Cache Creek terranes, and a map showing their areal distribution,
covering the Laberge, Whitehorse, Teslin, Skagway, Atlin, Tulsequah, Dease Lake, Cry Lake, Telegraph Creek,
Spatsizi River, Iskut River, and Bowser Lake map sheets. These samples vary from Mississippian to Triassic in
age. All of the samples have been re‐assessed, and the conodont taxonomy has been updated. Reported
stratigraphic ages have been confirmed or, in some instances, modified. This compilation reflects the current
state of knowledge of conodont palaeontology in this area, and serves as a baseline for ongoing and future
work in these regions. Additional sample collection and analysis is underway to supplement the archival data,
and to refine biostratigraphic correlations in the Stikine and Cache Creek terranes. Comparison of the conodont
faunas from these terranes will help to constrain the tectonic relationships between them during the late
Paleozoic and the early Mesozoic.
Craig GREEN University of Victoria, British Columbia
Geological Setting of the Rock Canyon Creek REE‐Fluorite Deposit, BC, Canada
Co‐authors: George J. Simandl, Suzanne Paradis, Fiona Katay, Mihoko Hoshino, Yoshiaki Kon, Shunsuke Kodama
and Chris Graf
Poster 53
The Rock Canyon Creek rare earth element (REE)‐fluorite deposit lies within the foreland fold and thrust belt of
the Canadian Cordillera, 300 metres east of the Munroe Lake thrust fault, which, in the deposit area, divides
the Main Ranges from the Front Ranges of the Canadian Rocky Mountains. The deposit is hosted by the un‐
subdivided Middle Devonian Cedared and Burnais formations, consisting mainly of dolostones, solution‐
collapse breccia, and laminated silty, calcareous gypsum. Fluorite bearing outcrops occur over an area 3300 by
750 metres. The steeply dipping REE‐fluorite zone was intercepted by drilling along strike for more than 1100
metres, to a depth of 124 metres; remains open along strike and dip, and may be over 50 metres thick. Based
on surface mapping and borehole logging, the deposit appears to be concordant with stratigraphy. Most of the
mineralization occurs as breccias and fracture fillings in fluorite‐impregnated dolostone. Fluorite
concentrations vary from less than 1% to 13.5% by weight, and light REE (Ʃ Ce+La+Nd) concentrations vary
from trace to 2.8%. REE are hosted mainly by bastnasite‐(Ce), parisite‐(Ce), synchysite‐(Ce), and REE‐bearing
phosphates.
Bulk rock geochemistry, petrography, mineral chemistry, fluid inclusion studies and age‐dating of pyrite
mineralization using Re‐Os isotope system, and monazite using U‐Pb isotope system will be used to
characterize the mineralizing system and to compare it with those responsible for the formation of Mississippi
Valley‐type deposits.
Hiruni GUNAWARDANA Western University, Ontario
Use of Anisotropy of Magnetic Susceptibility in Cu and PGE bearing gabbroic units in Marathon ON,
to analyse petro fabrics
20
Co‐author: Philip J.A. McCausland
Poster 104
A study of petro fabric assessment of Cu and PGE bearing gabbroic units is conducted on drill core samples
obtained from Marathon, ON. The samples were obtained from three mineralization zones and were analysed
with the use of Anisotropy of Magnetic Susceptibility (AMS). These magmatic Cu‐PGE sulphide deposits are
considered to form within magma conduit style settings. As expected, bulk magnetic anisotropy is influenced
with the preferred orientation of the long axes of grains of magnetite which is similar to the overall petro‐fabric
of the samples defining the flow direction of the magma. Susceptibility ellipsoids were constructed with the
analysis of AMS measurements and were plotted on a Flinn diagram to investigate the dominant petro fabric
textures, indicating the presence of a well‐defined planner fabric. Samples that gave results of the highest
degree of planar fabrics were from the Two Ducklake Gabbro lithology; the primary lithological host of most of
the Marathon deposit of Cu and PGE. Streonet projection of the directional distribution analysis of the
maximum and intermediate vector directions of the susceptibility ellipsoid orientations gives a well‐defined
planner fabric orientation direction existing within the rocks. This planner fabric strikes at 350 and dips at 20°
to the west, agreeing quite well with the orientation of the main mineralization unit, the two Ducklake Gabbro.
Therefore the AMS fabric orientation seem to agree quite well with the orientation of the mineralization unit,
indicating a potential tool that can be used during investigations of geophysical vectoring in mineral
exploration.
Tian HAN British Columbia Geological Survey, British Columbia
New British Columbia lithogeochemical database: Development and preliminary data release
Co‐authors: Alexei S. Rukhlov, Mustafa Naziri and Adrienne Moy
Poster 12
A new database system was developed to maintain, update, and manage the province‐wide lithogeochemical
data collected by the British Columbia Geological Survey (BCGS) geoscientists and their research partners. The
database was currently populated with the data compiled from 214 BCGS publications (e.g. OpenFiles,
GeoFiles, Geological Fieldwork, Geoscience Maps, Bulletins, etc.) between 1986 and 2015, including ~11,000
samples with about 250,000 determinations analyzed by 26 analytical methods in 21 laboratories. The
operation of this database was conducted through a semi‐automated process for data compiling, quality
control, uploading, and product generation, which facilitates consistent, standardized, and long term data
storage and update, and regular data release. For this preliminary data release, we derived the data product
from the database and made it available to the mineral exploration industry and the general public. The
product was provided in a user‐friendly format, which can be easily brought into GIS and geochemical data
analytical environments for visualization and analysis.
Nathan HAYWARD Geological Survey of Canada, British Columbia
21
Reconsideration of Cenozoic drainage evolution in southern Yukon, through Digital Terrain Model
restoration of the Tintina Fault
Co‐authors: Jim Ryan and Lionel Jackson
Poster 80
The impact of Tintina fault displacement on the development of the Yukon River and drainage basin of central
Yukon is investigated through geophysical and hydrological modeling of digital terrain model data. Geological
evidence suggests that the Yukon plateaus have been stable features since the late Mesozoic, with relatively
low incision rates over the last 100 Ma. The Tintina fault is interpreted to have experienced ~430 km of dextral
displacement, primarily during the Eocene. However, the alignment of channels across the fault at specific
displacements, coupled with recent seismicity/fault activity, suggest that the fault may have moved in stages
over a broader timespan.
Models show that Yukon River drainage northwestward into Alaska via the ancestral Kwikhpak River
has only been viable at fault restored displacements of 0 to ~50‐55 km. At restored displacements of 230 to
430 km, our models illustrate that paleo Yukon River drainage may have flowed eastward into the continental
interior via an ancestral Liard River. We interpret the drainage reversals convincingly attributed to the effects
of Pliocene glaciation as an overprint on far more ancient Yukon River reversals attributed tectonic
displacements along the Tintina fault in the early Cenozoic. This revised drainage evolution has wide‐reaching
implications for surficial deposits, and most notably for placer gold deposits, and the flow direction and
channel geometries of these ancient rivers. This technique could be applied to other transcontinental fault
zones around the world to reconsider the neotectonic effect on landscape evolution; this is not likely a
phenomenon unique to Yukon.
David HEBERLEIN Heberlein Geoconsulting, British Columbia
Preliminary results of a geochemical investigation of halogen and other volatile compounds related
to mineralization: Lara volcanogenic massive‐sulphide deposit (NTS 092B/13) and Mount
Washington epithermal gold prospect (NTS 092F/14), Vancouver Island, BC
Co‐author: C.E. Dunn
Poster 37
The halogens (F, Cl, Br and I) are common constituents of igneous, metamorphic and sedimentary rocks. They
are particularly enriched in differentiated magmas; the hydrothermal fluids and volatile compounds derived
from them play an important role in the mobilization and transport of metals in ore‐forming systems. This
study seeks to assess their usefulness as exploration tools by establishing their signatures and those of other
volatile compounds (e.g. ammonium) in common vegetation species, transpired fluids from trees, Ah horizon
soils, soil emanations and snow over concealed mineralized bodies at two localities on Vancouver Island. At the
Lara VMS deposit near Chemainus sampling was carried out on a 100 by 100 m grid over the mineralized
stratigraphy. A single multi‐media transect was sampled over the epithermal Au system at Mt. Washington
near Courtenay, with additional parallel lines sampled for mountain hemlock and Ah soils.
22
Much of the work done to date has focussed on developing effective analytical methods for complex
organic‐rich sample media that cannot be determined by traditional analytical methods. Most results are
pending. Preliminary results show that at Lara there is a strong enrichment of fluorine in western sword fern
compared to other common vegetation species, and positive but variable responses of all the halogens and
ammonium in transpired fluids over Au mineralization at Mt. Washington. The clearest signature for fluorine in
vegetation was obtained by first reducing the tissues to ash, thereby eliminating the multiple interferences
from the organic compounds in the dried tissues.
Christopher HERRON Mineral Deposit Research Unit, University of British Columbia, British Columbia
Defining the Carbonate Alteration Footprint of the Cortez Hills Carlin‐type Au Deposit in North‐
Central Nevada, USA Using Stable Isotopes 13C and 18O as a Mineral Exploration Tool
Co‐authors: G. Dipple and A. Beinlich
Poster 55
A stable isotopic approach was applied to the Cortez Hills 10 Moz Carlin‐type gold deposit (42‐37 Ma) to define
the carbonate alteration footprint. This deposit is located in central Nevada, USA along the Battle Mountain‐
Eureka Trend within the Cortez District.The goals of the study were to elucidate fluid flow processes and to
define the distal alteration halo surrounding the deposit. The alteration footprint was examined at the micro
(mm) ‐ to macroscales (km) through field mapping, core logging and sampling of drill core, pulped rock, surface
areas and reverse‐circulation chips. These samples are combined with detailed lithogeochemistry and stable
carbon and oxygen isotope analyses that were performed using the off‐axis integrated cavity output
spectroscopy analyzer [1].
Results from ~1400 drill hole pulped rock samples display a correlation between stable oxygen
compositions and Carlin‐type pathfinder elements (As, Au, Hg, Sb, Tl) that can be utilized as a vectoring tool for
fluid pathways and mineralization. The most altered areas (18O is 2‐18‰ VSMOW) are proximal and within the
orezones and major faults. The results show that the alteration halo extends for >2 km. Alteration is focused
along faults and sub‐horizontally permeable strata. Fluid flow predominantly upwards and outwards from is
interpreted to reflect the escape of spent mineralizing fluids.
[1] Barker, S., Dipple, G.M., Dong, F., Baer,D. (2009). Use of Laser Spectroscopy to Measure the 13C/12C and 18O/16O Compositions of Carbonate Minerals. Analytical Chemistry. V.83: 2220‐2226."
Mihoko HOSHINO Geological Survey of Japan, Japan
Mineralogy of the Rock Canyon Creek REE‐Fluorite Deposit, British Columbia, Canada
Co‐authors: Yoshiaki Kon, Shinsuke Kodama, George J. Simandl, Chizuru Namatame, Izumi Matsunaga and
Tetsuichi Takagi
Poster 9
23
The Rock Canyon Creek deposit is one of the most promising, drill‐investigated, REE‐bearing deposits in British
Columbia. The main mineralized zone was defined by drilling over a strike length of 1100 metres and
mineralization extends to a depth of more than 124 metres. The SEM‐EDS (JEOL JSM‐6610LV), powder‐XRD
(Rigaku SmartLab) and Raman Spectroscopy (JASCO NRS‐5100) analyses were carried out on samples from this
zone. Mineralization consists of various proportions of dolomite, fluorite, quartz, K‐feldspar, barite, porous
apatite, pyrite, REE carbonates [bastnasite‐(Ce), parisite‐(Ce), synchysite‐(Ce)], and REE‐bearing phosphates
[monazite‐(Ce), crandallite group minerals]. Barite and fluorite veinlets, and veinlets containing REE minerals,
fluorite, barite and pyrite are cut by late calcite filled fractures. REE carbonates and mixture of REE phosphates
are spatially associated with pyrite, barite and fluorite. Most of the pyrite in surface samples was destroyed by
weathering and at depth, pyrite rims are replaced by hematite.
Preliminary results indicate that the bastnasite‐(Ce) contains 8.7‐26.7wt% La, 24.3‐34.4 wt% Ce, from
detection limit (dt)– 4.7wt% Pr, 8.2‐24.1 wt% Nd, dt – 2.84 wt% Sm, and dt‐8.42 wt% Th. Synchysite‐(Ce)
contains 5.2‐17.4 wt% La, 16.6‐25.3 wt% Ce, dt‐8.3 wt% Pr, 2.6‐19.4 wt% Nd, dt‐2.13 wt% Y and dt‐3.7 wt% Th.
Monazite contains 11.03‐13.03 wt% P, 14.15‐18.95 wt% La, 21.46‐32‐98 wt% Ce, 4.01‐8.80wt% Nd, and dt‐3.55
wt% Th. Monazite‐(Ce) includes impurity elements like Al, Ca, which suggests that monazite‐(Ce) are altered.
Textures suggest REE‐bearing minerals, fluorite, barite and pyrite are hydrothermal origin. The compositions of
REE‐bearing minerals probably reflect the evolution of hydrothermal fluids and/or geographic position of the
samples within the mineralizing system.
Trygve HÖY Geoscience BC, British Columbia
Geology of the Christian Valley map‐area (082E/10), Boundary District, southern BC
Co‐author: Wayne Jackaman
Poster 22
Geological mapping of the Christian Valley map sheet is a continuation of a study of the structural and
magmatic controls of mineralization in the Penticton east‐half map sheet in southern British Columbia. The
area is within the Boundary District immediately northeast of the Beaverdell mining camp and approximately
60 km north of the Greenwood camp. Mining in the Beaverdell camp produced approximately 1,076,000 kg Ag
and 520 kg Au from narrow, high‐grade lead‐zinc veins. The Phoenix mine in the Greenwood camp produced
more than 28,340 kg Au, 183,035 kg Ag and 235,692 T Cu until its closure in 1978, and several other deposits in
the camp continue to be actively explored. Historical exploration in the western part of the Christian Valley
map‐area has been directed mainly towards uranium deposits and, to a lesser extent, precious‐ and base‐metal
mineralization similar to that in the Beaverdell camp.
The western part of the map‐area is underlain by a north‐trending graben, the Rock Creek graben, that
extends northward for more than 80 km from south of the US border, through the Boundary District and into
the northern part of the Christian Valley map sheet. The graben is filled with clastic and volcanic rocks of the
Eocene Penticton Group that unconformably overlie late Paleozoic metasedimentary and metavolcanic rocks,
middle Jurassic intrusions, and early Eocene granites tentatively correlated with the Okanagan batholith. In
contrast, younger Eocene intrusions, mainly syenite of the Coryell suite, intrude Marron Formation volcanics of
the Penticton Group within the graben. Hence, the Marron Formation was deposited between these two
magmatic pulses; recent and ongoing Ar‐Ar dating of these intrusions and volcanic rocks in the Christian Valley
24
map area and the Almond Mountain map‐area immediately south (J. Gabites, the University of British
Columbia) therefore tentatively restrict the age of deposition of the Marron Formation to 57‐51 Ma.
The Rock Creek graben may have formed after deposition of the Marron Formation that is preserved in
its core, or by growth faulting during deposition. At least some movement along the bounding graben faults
clearly post‐dates the Marron, supporting a model that these Eocene volcanics are remnants of widespread
volcanism, preserved from erosion in down‐dropped blocks. However, fault zones along the western margin of
the graben are locally cut by fresh, undeformed dykes, lithologically similar to some phases of the Penticton
Group, suggesting initiation of graben growth during Eocene volcanism. Dating of these dykes, and more
robust dating of the Marron Formation and granitic rocks that form the margins of the Rock Creek graben, will
help constrain the timing of movement along the bounding faults, the age span of the Marron Formation and
the age and controls of associated base and precious mineralization in the district.
Dillon HUME Simon Fraser University, British Columbia
Structural and Mineralogical Controls of Gold Mineralization at the Tajitos Project, Sonora, Mexico
Co‐authors: D. Marshall, J‐M. Staude, D. Gibson, D. Thorkelson, and F. Cazares
Poster 45
The Tajitos project in Northwestern Sonora is situated within the newly defined and studied Caborca Orogenic
Gold Belt (COGB). The COGB formed during the Late Cretaceous to Eocene under a compressional tectonic
regime associated with the Laramide Orogeny (e.g. Izaguirre et al., 2016). The Tajitos occurence displays many
of the characteristic features of orogenic gold deposits, including mineralization that is structurally‐controlled,
epigenetic, vein hosted and hosted by lower greenschist facies metamorphic rocks.
Field mapping, thin section and hand sample petrography, rock geochemistry, and a structural analysis
are consistent with gold mineralization primarily occuring in laminated quartz‐sericite fault fill veins, with
minor lower grade anomalies found in quartz‐pyrite extensional veining in quartz‐sericite‐pyrite and quartz‐
carbonate‐pyrite alteration adjacent to the fault fill veining. Gold occurs as interstial, anhedral disseminations
among quartz crystals in veins, as native gold with silver impurities, uytenbogaardite (Ag3AuS2), and petzite
(Ag3AuTe2). Locally, gold is spatially associated with sericite, calcite, pyrite, galena, and covellite.
The fault‐fill veins are predominantly steeply dipping with northwest‐southeast orientations. The meta‐
volcanic strata are tilted to the south‐southwest and gently folded about an ESE‐WNW fold axis. The strata
consists of bimodal dacitic to rhyolitic tuffs overlying basaltic to andesite flows. Locally, dioritic to gabbroic
pegmatite and late Tertiary felsic and mafic dykes intrude and cross‐cuts the stratigraphy. As well, alteration
haloes around fault fill and extensional veining make lithologic identification difficult. Both regionally and
locally at Tajitos, late extensional faulting has offset stratigraphy and overprinted deformation fabrics in fault
zones during reactivation.
Wayne JACKAMAN Noble Exploration Services, British Columbia
Ongoing Development of British Columbia’s Regional Geochemical Database Using Material Saved
from Previous Field Surveys
25
Poster 40
Reconnaissance‐scale regional geochemical survey programs have been conducted in BC since the early 1970s
and information derived from this work continues to guide and complement mineral exploration. Analytical
data is systematically collected as part of original field surveys and, more recently through the reanalysis of
archived materials. Re‐analysis initiatives are recognized as a cost‐effective means of improving the utility of
the existing geochemical database. To date thousands of samples have been successfully recovered from
storage and analyzed using modern analytical methods. Results provide lower detection levels for base and
precious metals as well as pathfinder and rare‐earth elements. They also generate improved data continuity
between surveys completed at different times and samples analyzed by different commercial laboratories. This
poster highlights the ongoing effort of Geoscience BC and government agencies to maintain and upgrade this
important geochemical data resource.
Paul JAGO BC Ministry of Energy & Mines, British Columbia
Mining, exploration and discovery in the North Central and Northeast regions, 2016
Poster 19
Challenges associated with low commodities prices and market volatility continued to affect the North Central
and Northeast regions in 2016 and four of five operational or fully permitted coal mines, and one metal mine,
remained on care and maintenance. One coal mine began restart activities immediately following a rebound in
metallurgical coal price that began in August. More grassroots to early stage exploration activity was tracked in
2016 perhaps indicating the initial stage of an improving cycle for mineral exploration and investment.
Underexplored parts of the two regions continue to generate interest for a variety of mineral deposit types
including porphyry copper‐gold ± silver, epithermal gold‐silver, and stratiform or vein‐hosted polymetallic
types; and also for coal and industrial minerals, including nephrite jade. Main highlights for 2016 included the
construction and commissioning of a permanent secondary crusher at Mt. Milligan mine (Centerra Gold Inc.);
restart of the Brule mine (Conuma Coal Resources Limited); review of a Mines Act permit application for the
proposed Murray River underground coal mine (HD Mining International Ltd.); advancement of several
environmental assessments in the review stage including Blackwater (New Gold Inc.), Kemess Underground
(AuRico Metals Inc.), Giscome (Graymont Western Canada Inc.), and Sukunka (Glencore plc); continued
delineation of an orebody at Kemess East (AuRico Metals Inc.); drilling programs that expanded or confirmed
areas of known mineralization at several projects including Kwanika (Serengeti Resources Inc.); new high‐
priority drill targets developed at several projects; and new discoveries that continue to be made at the
grassroots exploration level.
Darius KAMAL University of British Columbia, British Columbia
Textural characteristics and chemical composition of chlorite from the Guichon Creek Batholith,
south‐central British Columbia
26
Co‐authors: Robert G. Lee, Guillaume Lesage, and Kevin Byrne
Poster 64
The Upper Triassic Guichon Creek batholith is located within the Canadian Cordillera as part of the
Intermontane Belt, and has surface area of approximately 1,000 km2. The batholith hosts the Highland Valley
Copper calc‐alkaline porphyry district, which comprises 5 known mineralized centres: Bethlehem, J.A.,
Highmont, Lornex, and Valley. Chlorite forms as an alteration byproduct of primary minerals in porphyry
copper deposits via hydrothermal fluid flow from a magmatic source and interaction between meteoric water
and wallrocks. At Highland Valley, chlorite occurs either as part of the main and proximal sodic‐calcic alteration
assemblage (albite‐chlorite‐epidote±actinolite ± diopside ± garnet) or with the generally more distal white
mica‐chlorite‐prehnite assemblage. Characteristics of chlorite such as colour, structural composition, and
chemical composition vary due to cation substitution, which is directly affected by temperature, pressure, and
bulk rock composition. Petrographic observations and geochemical compositional tests (EMP) of chlorite
collected from the medial to distal areas of the Guichon Creek batholith were conducted to evaluate the
textural and chemical variations as a function of distance to mineralized centres for different styles of
alteration. Chlorite associated with sodic‐calcic alteration displays anomalous blue birefringence, showing a
more Fe‐rich composition, as opposed to green chlorite which indicates Mg‐rich composition. These
petrographic observations and geochemical data will enhance the description of the alteration facies and their
distribution at HVC, and can potentially be used to vector towards Cu mineralization. NSERC‐CMIC Footprints
Exploration Project Contribution #119
Susan KARL U.S. Geological Survey, USA
GIS‐based identification of areas that have potential for lode gold deposits in Alaska
Co‐authors: K.A. Labay, N.B. Shew, B. Wang, and M. Granitto
Poster 112
Alaska has three operating lode gold mines and numerous widely distributed historic placer gold operations
that presumably indicate as yet undiscovered lode gold sources. Geographic Information System‐based
analyses of statewide geoscientific databases were applied to evaluate potential for lode gold deposits in
Alaska. The analyses addressed orogenic, epithermal, intrusion‐related, and non‐specific lode gold deposit
types. Key features, including host rock composition, mineralogy reported from heavy mineral concentrates
and site descriptions, pathfinder element geochemistry, alteration, and other factors that characterize these
deposit types were integrated in the analyses to evaluate whether the deposit types could be distinguished in
Alaska. Despite significant overlap in characteristics of these gold deposit types, the exercise resulted in maps
that identified areas having favorability for each type. Areas characterized by 1) key features of orogenic gold
deposits, such as greenschist‐grade metamorphic rocks, quartz‐carbonate veins, and the presence of gold in
combination with sediment geochemistry and minerals containing arsenic and base metals, include the Seward
Peninsula, Kuskokwim Mountains, Alaska Range, southern Alaska, and southeast Alaska; 2) key features of
intrusion‐related gold deposits, such as shallowly exposed intrusive rocks, dike swarms, hydrothermal
alteration, and gold with sediment geochemistry and minerals containing bismuth, antimony, arsenic, cobalt,
copper, and molybdenum, include the Kuskokwim Mountains, east‐central Alaska, and Alaska Range; and 3)
27
key features of epithermal gold deposits, such as felsic extrusive and hypabyssal igneous rocks, sulfosalts, and
gold with sediment geochemistry and minerals containing silver, mercury, and tellurides, include the
Kuskokwim Mountains, Yukon Tanana uplands, and Alaska Range.
Fiona KATAY Ministry of Energy and Mines, British Columbia
Exploration and Mining in Southeastern BC, 2015‐2016
Poster 18
Exploration and mining continued in the southeastern region of British Columbia in 2016. Five operating
metallurgical coal mines in the Elk Valley account for the majority of Canada’s coal production, and exports.
Mine expansion plans continue at 4 of the 5 mines, and several other projects are at various stages between
exploration and environmental assessment.
Several other mines in the region produce industrial minerals including silica, magnesite, gypsum,
graphite, and phosphate. Placer mining occurs throughout the region, and several small operations produce
aggregate, sand and gravel, and dimension stone. Several projects are advancing towards bulk sampling stages,
re‐starts and upgrades of existing small underground operations, and mill facilities. Exploration in the region
continues for a variety of deposit‐types, including: SEDEX, vein, and sediment‐hosted copper targets in the
Mesoproterozoic Purcell Anticlinorium; stratiform, VMS, replacement‐style, vein, and skarn mineralization in
the Kootenay Arc; skarn, epithermal, porphyry, and vein targets in the accreted terranes of Quesnellia and the
Okanagan sub‐terrane; MVT, REE and industrial minerals in the Rocky Mountain foreland belt; and Mesozoic
vein and shear‐related precious metal mineralization throughout the region.
Rachel KIM Mineral Deposit Research Unit, University of British Columbia, British Columbia
New U‐Pb age constraints and lithogeochemical classification for Late Cretaceous volcanics in the
TREK project area, central British Columbia
Co‐authors: J.J. Angen and C.J.R. Hart
Poster 31
Recent development of the ~10Moz Blackwater Au‐Ag intermediate sulfidation epithermal deposit in central
British Columbia (BC) has generated interest in the host rocks that belong to the Late Cretaceous Kasalka
Group. These are consequentially considered to be highly prospective for exploration; however targeting
efforts have been hindered by difficulties in distinguishing the Kasalka Group from similar‐looking Jurassic and
Eocene volcanic rocks across the Nechako Plateau. Reported age constraints at Blackwater range from 69‐73
Ma, but previous regional mapping and studies have provided a wide range of reported K‐Ar and U‐Pb ages for
rocks assigned to the Kasalka Group, spanning from 67 to 108 Ma (MacIntyre, 1978; Leitch et al., 1991;
Friedman et al., 2001; Ferbey and Diakow, 2012). Recent regional‐scale bedrock mapping with Geoscience BC’s
TREK project has identified new exposures of Late Cretaceous volcanics in the Nechako Plateau. New U‐Pb
28
zircon geochronology, lithogeochemistry and petrography has allowed for an updated characterization of the
Kasalka Group in the Nechako Plateau which will aid future exploration targeting efforts.
Julia KING Geoscience North, British Columbia
FREE‐D: Viewing and Integrating Spatial Data Using Free Software
Co‐author: Alan R. King
Poster 111
2D and 3D GIS software are powerful and increasingly essential tools for geologists. The cost of these
ubiquitous products can range from hundreds to tens of thousands of dollars per year. These costs are a
significant barrier to extracting knowledge from data for academics, students, mineral exploration companies,
and the public; however, these platforms are essential to optimizing the use of public and private data.
This poster summarizes open source and/or free 1D, 2D GIS, and 3D and 4D visualization tools from academic
and industry sources, with the goal of sharing spatial data platforms for all to use, share, interpret, and
communicate geoscientific data.
These software packages include: The Kansas Geological Survey 1D tool, 2D QGIS, 2D gvSIG, 2D Google
Earth Engine, Mira Geoscience's 3D Geoscience Analyst, Geosoft's 2‐3D Oasis Montaj Viewer, 4D ParaviewGeo,
and UNAVCO's 4D GEON IDV software tools. Examples are taken from B.C. mineral exploration, geo‐hazard
and mapping projects.
In addition to enhancing data interpretation, these tools can be used to promote understanding and
communication between all stakeholders: the public, non‐earth scientists, students, academics, stakeholders,
government and industry.
Nikolett KOVACS Mineral Deposit Research Unit, University of British Columbia, British Columbia
New geological insights into the Carmacks Copper Cu‐Au‐Ag deposit, central Yukon
Co‐authors: M.M. Allan, A. Zagorevski, J.E. Milton, and C.J.R. Hart
Poster 96
The Carmacks Copper Cu‐Au‐Ag deposit is hosted in compositionally heterogeneous, foliated and folded, and
variably migmatitic metamorphic rocks, which occur as elongate, NNW‐trending inliers in Early Jurassic
granitoids of the Granite Mountain batholith. Hypogene copper mineralization is restricted to metamorphic
host rocks, and occurs both as foliation‐parallel chalcopyrite‐dominant stringers in schistose rocks, and as net‐
textured bornite‐chalcopyrite‐dominant sulphides in the migmatitic rocks prevalent along the eastern margin
of the largest metamorphic inlier. The latter style of mineralization is interpreted to originate from a sulphide
melt phase generated during partial melting of a previously mineralized protolith, during emplacement of the
Granite Mountain batholith.
29
Gabriel LAUZON Université du Québec à Montréal, Quebec
Till Composition and Surficial Geology of the Wholdaia‐Abitau Lakes Area, South Rae Craton,
Northwest Territories
Co‐authors: J. Campbell, M. Roy, A.S. Dyke, and S. Pehrsson
Poster 98
In 2015, 1:100 000 scale surficial geology mapping and a reconnaissance‐scale till sampling survey were
completed within NTS map sheets 75A and 75B by the Geological Survey of Canada during the first year of the
South Rae Activity of the Geo‐Mapping for Energy and Minerals Program (GEM‐2). This previously unmapped
area lies in the southern part of the Rae Craton, Northwest Territories. This region is extensively covered with
glacial sediments with bedrock exposure generally less than 10%. Ground observations were recorded at 157
sites and 94 till samples were collected for compositional analyses including geochemical and heavy minerals.
Erosional ice‐flow indicators (e.g. striations, roches moutonées) and streamlined landforms record at least four
phases of ice flow. A poorly defined old flow of unknown sense (SSE/NNW) and temporal relationship is
recorded at a few sites. Well defined indicators reveal a clockwise rotation in regional ice‐flow directions,
shifting from a southward to a southwestward flow. A late deglacial westward flow is recorded only in the
north part of the map area. The dominant regional ice flow direction is to the southwest. The sediment cover
consists mostly of till (till veneer, till blanket, hummocky till) intersected by NE‐SW trending eskers systems and
subglacial meltwater corridors.
The poster will present preliminary results focusing on the ice‐flow reconstruction, till composition and
the spatial distribution of major and trace elements of the till matrix geochemistry, gold grains and selected
indicator minerals.
Emily LAYCOCK McGill University, Quebec
The Snowfield Deposit: A Gold‐Enriched Copper Porphyry System in NW British Columbia
Co‐authors: A.E. William‐Jones, and J. Clark
Poster 50
An important question in understanding the genesis of porphyry deposits, is why are some of these deposits
unusually enriched in gold? The Snowfield porphyry in Northwestern British Columbia, provides a unique
opportunity to address this issue. A review of the literature suggests that it is one of the most gold‐enriched
porphyry systems in the world, with unusually high gold/copper ratios. In addition to the exceptionally high
Au:Cu ratio, the extensive quartz‐sericite‐pyrite alteration assemblage observed at Snowfield, cannot be
satisfactorily explained by the classic telescoping porphyry model. It may reflect a more complex hydrothermal
evolution.
The aim of the research is to gain a better understanding of the nature of the hydrothermal fluids and
the physiochemical conditions related to the gold mineralisation and alteration at Snowfield. These conditions
will be interpreted within the evolution of the porphyry system. The overarching objectives are to use this
30
information to determine why the deposit is unusually rich in gold, validate new field strategies for mapping
alteration, and develop tools for vectoring to mineralisation in future exploration. This poster will present some
initial results, which include detailed petrography and SEM imaging that display important mineral
relationships and textures, as well as preliminary alteration mapping using a field portable spectrometer.
Well‐Shen LEE Mineral Deposit Research Unit, University of British Columbia, British Columbia
A Petrographic Comparison of Gold‐bearing Veins Near the 5 Moz Coffee Gold Deposit, Dawson
Range, Yukon
Co‐author: Murray M. Allan, Kathryn R.G. MacWilliam, Stephen Bartlett, Greg McKenzie, and Craig J.R. Hart
Poster 95
The discovery of the 5 Moz Coffee gold deposit in 2009 emphasizes the exploration potential of the Dawson
Range, Yukon, but relatively little is known about the metallogeny of Coffee or related gold prospects in the
region. This study focuses on three mid‐Cretaceous hydrothermal vein systems in close proximity to Goldcorp’s
Coffee deposit: ‐Sugar, Boulevard and Toni Tiger. The limited amount of quartz veining associated with
mineralization at Coffee has made determinations of fluid chemistry and ore‐forming conditions difficult to
constrain through fluid inclusion studies. This study compares the vein mineralogy, paragenenesis, sulphide
minerals and fluid inclusion composition of similarly quartz‐carbonate‐sulphide veins in Boulevard, Sugar and
Toni Tiger, and to assess possible genetic relationships with gold mineralization at Coffee.
Mineralization features at Sugar and Boulevard are similar to those at Coffee, with (1) a strong Au‐As‐
Sb signature, (2) gold inferred to be largely present in solid solution in arsenian pyrite; and (3) sulphides
occurring as wall rock disseminations and in fault or vein breccias. Veins at Sugar and Boulevard share several
important characteristics: (1) a quartz‐carbonate ± arsenian pyrite ± arsenopyrite ± tetrahedrite ± stibnite
mineral assemblage; (2) common sulphide paragenesis of early euhedral pyrite and arsenopyrite overprinted
by late arsenian pyrite ± (native gold?); (3) syn‐mineralization polyphase breccia and shear structures.
Microthermometric data show mineralizing veins at Boulevard and Toni Tiger have a common parent fluid
containing ~3 wt% NaCl, 16 mol% CO2, trapped at >280°C and >1100 bars. However, quartz veins at Toni Tiger
are distinctive in that they contain molybdenite as the main sulphide mineral. These quartz‐molybdenite veins
are preceded by an earlier quartz‐garnet vein generation that is more intimately associated with calc‐silicate
alteration.
Guillaume LESAGE Mineral Deposit Research Unit, University of British Columbia, British Columbia
District‐scale porphyry‐related hydrothermal alteration and the quantitative use of feldspar
staining: the case of Highland Valley Copper, British Columbia
Co‐authors: Kevin Byrne, Robert G. Lee, and Craig J.R. Hart
Poster 63
31
The Highland Valley Copper district (HVC), near Kamloops, British Columbia, contains four mineralized porphyry
Cu ± Mo centers hosted in the Late Triassic Guichon Creek batholith. Porphyry copper systems form when large
quantities of magmatic fluids are exsolved from a magma chamber and react with the country rock, causing
hydrothermal alteration that may include changes in feldspar species modal percentages. The spatial
distribution of district‐scale hydrothermal alteration at HVC is strongly controlled by structural permeability.
The main alteration assemblages observed include: (1) potassic alteration (K‐feldspar±biotite) striking
dominantly NNE and approximately E, (2) sodic‐calcic alteration (albite‐chlorite‐
epidote±actinolite±diopside±garnet) striking dominantly NNE and WNW, (3) coarse‐grained white mica
alteration striking dominantly NE and NW, and (4) white mica‐chlorite‐prehnite alteration striking dominantly
NNE. Quantitative image analysis of feldspar stained rock slabs using the ImageJ software is a cheap and
effective technique to assess the nature and intensity of hydrothermal alteration. Vein‐controlled K‐feldspar
alteration can be identified by analyzing the shape and size of particle fit ellipses in the slab and detecting
samples containing anomalously large and elongate ellipses corresponding to interconnected grains in veins.
Because sodic‐calcic alteration destroys K‐feldspar, it can be identified by a ratio of K‐feldspar to plagioclase,
and a K‐feldspar particle count per area decreasing by up to three and two orders of magnitude respectively.
Quantifying feldspar alteration can significantly improve the mapping of alteration distribution and intensity by
recognizing otherwise cryptic features not consistently observed by geologists in the field. NSERC‐CMIC Mineral
Exploration Footprints Project Contribution Number 113.
Gloria LOPEZ Alberta Geological Survey, Alberta
Alberta Interactive Minerals Map: A View to Alberta's Metallic and Industrial Mineral Occurrences
Co‐authors: Rastislav Elgr, John Pawlowicz, Jill Weiss, Noah Nahachewsky, Lori Walton, and Dean Rokosh
Poster 110
Historical records document nearly 100 years of mineral exploration and industrial mineral production in
Alberta. However, compared with other jurisdictions in Canada, mineral development within the province
remains at an early stage. The absence of a single repository for mineral data provided the impetus to review
and inventory existing data held at the Alberta Geological Survey (AGS). A collaboration between the AGS and
Alberta Energy resulted in the Alberta Interactive Minerals Map (AIMM), a web‐based easy to use interactive
tool for viewing and querying information about Alberta's metallic and industrial mineral occurrences. This
project has involved a significant compilation effort to gather mineral information from existing holdings,
industry reports, journal publications and mineral assessment reports. Since its 2015 release, AIMM has been
accessed over 15,000 times, providing local and global users with an array of base maps, layers, datasets, and
supporting information for viewing and downloading mineral data. Currently, AIMM shows location and
characteristics of mineral occurrences in the province including industrial mineral mines, industry resource
estimates (including historical), kimberlite indicator mineral data and mineral survey results for metallic,
industrial minerals and also wastewater from formation brines generated during oil and gas production
activity. AIMM also displays the surficial and subsurface geology of Alberta, new glacial landform, sediment
thickness and bedrock topography as base maps. AGS will continue to migrate, validate and analyze mineral
data into AIMM to ensure efficient and timely dissemination of information.
32
Meaghan MACPHERSON Mineral Deposit Research Unit, University of British Columbia, British Columbia
The genetic and exploration significance of ferromagnesian silicate compositions for
metamorphosed sediment‐hosted Cu‐Au mineralization in the Kanmantoo Group, South Australia
Co‐authors: Paul G. Spry, Katherine A. Tott, Alan E. Koenig, and Joseph Ogierman
Poster 100
Multiply deformed sedimentary rocks of the Kanmantoo Group, South Australia, which were metamorphosed
to the amphibolite facies, host Cu‐Au and Pb‐Zn‐Ag deposits. The Kanmantoo Cu‐Au deposit, the largest in the
Kanmantoo Group (31.3 Mt @ 0.8% Cu and 0.2 g/t Au), is characterized by discordant and pipe‐like orebodies
(Kavanagh and Spitfire) along with concordant mineralization (Nugent). Previous studies have suggested a
syngenetic origin for the Pb‐Zn‐Ag deposits whereas syngenetic and epigenetic models have been proposed for
the Kanmantoo deposit. The recognition of the stratiform nature of the Nugent orebody at Kanmantoo and of a
zone chalcopyrite‐pyrrhotite‐magnetite‐rich rocks at the Wheal Ellen Pb‐Zn‐Ag deposit, which is the dominant
mineralogy in the Kanmantoo deposit, suggests a genetic link between the two deposit types.
A principal component analysis of garnet compositions further supports the concept of a link between
these ore types. Garnet in country rock schists within the Kanmantoo Group contains approximately 5‐10 wt.%
MnO, whereas that in Pb‐Zn‐Ag deposits contains up to 30 wt.% MnO. The MnO content of garnet in the
Kavanagh and Spitfire orebodies contains 2‐4 wt.% MnO, whereas up to 10 wt.% MnO occurs in garnet from
the Nugent orebody. The distinctive compositions of garnet at Kanmantoo, along with those for staurolite (up
to 2000 ppm Mn and up to 1.38 wt.% ZnO), biotite (up to 200 ppm Mn and Zn), and chlorite (up to 650 ppm Mn
and up to 180 ppm Zn) constitutes a potential pathfinder to Cu‐Au deposits in the Kanmantoo Group.
Kathryn MACWILLIAM Mineral Deposit Research Unit, University of British Columbia, British Columbia
Uncovering alteration through petrography, geochemistry and hyperspectral analysis at the Coffee
Gold deposit, Dawson Range, Yukon
Co‐authors: Murray M. Allan, Lionel C. Fonteneau, Craig J.R. Hart, and Tim Smith
Poster 94
Determining the hydrothermal alteration associated with mineralization is important for understanding the
genesis of a mineral deposit. This is particularly important where alteration is cryptic, and not easily identified
by traditional techniques such as core logging and petrography. The Coffee Gold deposit is a mid‐Cretaceous,
structurally controlled, gold only, near surface and oxidized deposit with a large (5 Moz) resource located in the
Dawson Range, Yukon. Mineralization is hosted in meta‐ psammites and semi‐pelites, orthogneiss, and biotite
granite, with gold occurring in solid solution within arsenian pyrite, and where oxidized, as nanoparticles of
native gold within pyrite rims. The dominant alteration assemblage consists of micro‐ to cryptocrystalline
quartz‐illite‐kaolinite‐dolomite that is intricately intergrown. Hyperspectral VNIR/SWIR analysis, petrography,
alteration geochemistry, and imagery analysis highlights a complex association of alteration minerals.
Alteration imagery and spectral analysis emphasize intricate textural associations of white mica, kaolinite, and
33
carbonate. Both kaolinite and white mica predominantly exhibit moderate to low crystallinities suggesting low
temperatures of formation (~200°C). White mica compositions range from Na‐rich paragonite to Fe‐rich
phengite, the latter commonly replaced by auriferous arsenian pyrite. Ammonium‐bearing white mica is
observed in mineralized and/or oxidized rocks suggesting fluid interaction with carbonaceous host rocks. Iron
spectrum in carbonate‐rich samples provides further evidence for Fe‐rich and non‐Fe carbonate phases.
Goethite is the predominant oxide mineral, and is commonly intergrown with hematite. These alteration
features indicate a low temperature, moderate pH (4‐5) hydrothermal fluid, which interacted with locally
carbonaceous host rocks was responsible for auriferous pyrite mineralization.
Neal MANKINS Oregon State University, USA
Vein Orientation and Structural Geology of the Boulder Batholith, Mount Thompson Quadrangle,
southwestern Montana
Poster 59
The Mount Thompson 7.5 Quadrangle is located in the central Boulder Batholith, between Butte and Helena.
The Boulder batholith is host to numerous metalliferous vein deposits, including those in the Butte District.
Recent USGS (EDMAP)‐funded geologic mapping at 1:24,000 scale in the Mount Thompson Quadrangle
focussed on new measurement of vein and fault orientation and compilation of previous data. The orientations
of vein systems observed in the Mount Thompson Quadrangle are consistent throughout the Boulder
Batholith.
Several vein types are hosted in the Boulder Batholith and shortly post date emplacement of the 76 Ma
Butte granite. Two distinct vein orientations have been identified on stereonet plots: 1) massive milky‐grey
East‐West 98˚ striking quartz veins with dip range of 73˚North‐72˚South, and 2) NE‐SW (azimuth 157˚) striking
quartz‐chalcedony veins with dip range 65˚NW‐76˚SE. Vein mineralogy includes three subsets: 1) massive grey
quartz 70‐80% of which are locally vuggy quartz with abundant sulphides (Py>Ga>Sl>Cp), 2) quartz‐sulphide‐
poor veins 65% with chalcedony, 3) cm‐scale milky quartz veins 20% with tourmaline. Additionally, a younger
set of sulphide‐rich (Py>Sl>Ga) veins at the Montana Tunnels Mine cut the ~50 Ma diatreme breccia and a
Lowland Creek Volcanics pyroclastic vent. The Boulder batholith veins are systematically zoned on the km scale
around heat centers (e.g., Comet and Occidental Plateau) from high to low temperature. Temperature zoning
occurs as tourmaline, to quartz‐sulphide (Pb‐Zn‐Ag±Cu‐Au), to quartz‐chalcedony in the periphery.
Erica MASSEY University of British Columbia Okanagan, British Columbia
A comparative study of glaciovolcanic palagonitization of tholeiitic and alkaline sideromelane at
Helgafell, Iceland and Wells Gray, BC Canada.
Co‐authors: J.D. Greenough and B.R. Edwards
Poster 103
34
Pleistocene glaciovolcanic eruptions occurred frequently beneath continental‐scale ice sheets that produced
vitric, fragmental volcanic deposits in Helgafell, Iceland (tholeiitic basalt) and Wells Gray, BC, Canada (alkali
olivine basalt). The deposits are highly susceptible to hydrothermal alteration that transforms sideromelane
(basaltic volcanic glass) into palagonite (early amorphous material) and secondary minerals (i.e. zeolites, clays
and sulfides). Compositional controls, mass transfer and geochemical‐textural relationships are investigated by
optical microscopy, Electron Microprobe Analysis and Laser Ablation Inductively Coupled Plasma Mass
Spectrometry, and geochemical modelling. Helgafell’s thinner (6‐10 microns) palagonite rims demarcate highly
vesicular (30.2%) sideromelane that has more gel‐material (18.9%) and secondary minerals (1.4%) than Wells
Gray’s microlite‐rich (12.3%) sideromelane. The thicknesses of palagonite rims are similar whether the
sideromelane is unaltered or completely altered and at least two important geochemical‐textural relationships
are formed during palagonitization (e.g. spherical textures and geochemical‐textural trends across palagonite
rims).
Multi‐dimensional scaling confirms that sideromelane composition, reflecting igneous processes,
strongly controls the chemistry of palagonite. Microprobe traverses identified eight prominent geochemical
trends across the glass‐palagonite interface and palagonite rim, which do not appear to be controlled by
sideromelane composition. Several element concentrations decrease in palagonite, including Si (by ~3‐10%), Al,
Ca and Na, while Ti, Fe and Mg concentrations increase. Locally, the palagonite has an inner Ti‐rich zone. The
gradual increase in Mg across the palagonite rim may be indicative of changes in solubility and pH.
Mass balance calculations from Gresens’ isocons demonstrate that the calculated range of percent
mass transfer is strongly affected by assumptions about the concentrations of water inferred to be present in
palagonite. The calculations are also most consistent with a two‐stage process of mass transfer.
Martin MCCURDY Geological Survey of Canada, Ontario
Geochemical maps for Mineral Exploration: New Lake Sediment Data from Quebec and Labrador
Co‐authors: S.D. Amor, D. Corrigan, R.G. Garrett, and F. Solgadi
Poster 72
This poster highlights the GSC’s new multi‐element lake sediment geochemistry maps to be released in Spring
2017 that will support of mineral exploration in the Core Zone and Labrador Trough regions of Quebec and
Labrador. These maps present new and compiled data for the largest contiguous area ever covered by a
geochemical map in Canada and highlight for the first time a new geochemical province, as well as regional and
local scale anomalies. The new geochemical data and maps are the result of collaboration between the
Geological Survey of Canada, the Geological Survey of Newfoundland and Labrador, and the Ministère de
l'Énergie et des Ressources naturelles du Quebec, under the GEM2 Hudson‐Ungava Project.
Duncan MCLEISH McGill University, Quebec
The nature and origin of the Brucejack high‐grade epithermal gold deposit, British Columbia,
Canada
35
Co‐authors: Anthony E. Williams‐Jones and Warwick S. Board
Poster 47
A major challenge in understanding the genesis of epithermal gold deposits is that existing genetic models do
not satisfactorily explain the mechanisms responsible for high‐grade gold deposition at temperatures
characteristic of the epithermal realm (150–300°C). Although transport by dissolution in an aqueous
hydrothermal liquid is the widely‐proposed mechanism for mobilizing gold within Earth’s upper crust,
experiments have shown that the solubility of gold is too low in hydrothermal liquids at temperatures of <
400°C to account for the extraordinarily high grades observed in some epithermal deposits.
The Brucejack deposit, currently undergoing preproduction mine development in northwestern British
Columbia, is host to one of the highest grade epithermal gold deposits in the world. Results from our
preliminary petrographic and mineral‐chemistry investigations of mineralized quartz‐electrum±carbonate veins
from Brucejack indicate that the deposit formed from a hydrothermal system with a complex history of
multiple, possibly long‐lived mineralizing events. The formation of the five synmineral vein stages and
substages appear to have resulted from multiple pulses of fluid that circulated through the deposit under
dynamic physicochemical conditions, including possible fluid‐overpressure and silica‐dissolution events. We
aim to develop a detailed genetic model for Brucejack by: (1) continuing chemical and petrographic
characterisation of Brucejack ores and associated hydrothermal alteration, (2) determining the composition of
mineralising fluids through fluid inclusion analysis, and (3) reconstructing the physiochemical conditions that
controlled Au mineralisation through thermodynamic modelling. If successful, our study will improve on
existing genetic models for epithermal gold deposits and the strategies that guide their exploration.
Mitch MIHALYNUK British Columbia Geological Survey, British Columbia
Turtle Lake area geology, NTS 104M/15, northwest British Columbia
Co‐authors: Alex Zagorevski, Dejan Milidragovic, Maria Tsekhmistrenko and Nancy Joyce
Poster 3
Turtle Lake map area is bordered to the north by Yukon and is bisected by north‐south‐trending Tagish Lake. It
straddles the boundary between exotic oceanic crustal and mantle rocks of the Cache Creek terrane and coarse
clastic strata of the Early Jurassic Whitehorse Trough. Marine Whitehorse Trough sediments are believed to
have been deposited on the Late Triassic to Early Jurassic forearc of the Stikine terrane. Final juxtaposition of
Stikine and Cache Creek terranes was accommodated by collapse of the Whitehorse Trough before mid Middle
Jurassic time. However, newly documented and isotopically dated field relations point to an important episode
of faulting that involved early Late Cretaceous strata and significantly modified this boundary.
Dejan MILIDRAGOVIC British Columbia Geological Survey, British Columbia
The Mount Hickman ultramafic complex, northwestern British Columbia: an Fe‐rich Alaskan‐type
intrusion
36
Co‐authors: A. Zagorevski and J.B. Chapman
Poster 8
Middle to Late Triassic magmatism played a key role in the development of northern Stikinia and its prolific
porphyry mineralization. The majority of plutonic rocks emplaced during this period are felsic to intermediate;
ultramafic plutonic rocks are rare and may provide constraints on the early magmatic processes, influencing
both the Cu‐Mo‐Au and Ni‐Cu‐PGE mineralization in Stikinia. The Mount Hickman ultramafic complex is an
Alaskan‐type intrusion of Middle to Late Triassic age located in northwestern British Columbia. The cumulate
rocks of the complex are predominantly composed of olivine ±magnetite clinopyroxenite, but also include
subordinate serpentinized dunite, wehrlite, and gabbro. Magnetite is a volumetrically significant primary
phase, especially in magnetite‐olivine clinopyroxenite, where it may comprise up to 40 % by volume. In
contrast to most other Alaskan‐type intrusions, and terrestrial ultramafic plutons in general, the Mount
Hickman ultramafic complex has an unusually high concentration of FeOTOT, including ~21 wt. % in
serpentinized dunite. We consider three petrologically viable scenarios, which may account for the elevated
FeOTOT concentrations of the Mount Hickman complex dunite. These are: metasomatic enrichment, mixing
between genetically related basaltic magmas, and mixing between genetically unrelated primitive (basaltic)
and evolved (Fe‐enriched) magma. Preliminary considerations suggest that the high contents of FeOTOT in the
Mount Hickman ultramafic complex reflect mixing of relatively primitive high‐MgO silicate magma, and a dense
Fe‐Ti‐P –rich highly oxidized magma.
Deanna MILLER British Columbia Geological Survey, British Columbia
A Depth‐to‐Bedrock 3D Model Pilot Project for Ootsa Lake, Central BC: An Aid to Mineral
Exploration
Co‐authors: Stephen Rowins and Yao Cui
Poster 14
The British Columbia Geological Survey (BCGS) conducted a pilot project to test the methodology and
applicability of 3D modelling to generate a simple depth‐to‐bedrock predictive map for the Ootsa Lake
porphyry Cu‐Mo‐Au district using datasets provided by Gold Reach Resources. The completed depth‐to‐
bedrock model predicted the overburden thickness based on extrapolation between drillholes, surface
outcrops, and LiDAR data. Where combined with geophysical datasets and geochemical anomalies identified
from Regional Geochemical Survey (RGS) data, the depth‐to‐bedrock map has proven to be helpful in ranking
exploration targets. Geochemical anomalies that were located in areas of shallow cover ranked higher than
similar geochemical anomalies over areas of thicker overburden. This ranking was based on the fact that Ootsa
Lake is an area with variable depth‐to‐bedrock cover, thus this predictive model could reduce drilling costs by
avoiding those areas of deep cover where drillholes are easily lost or difficult to complete.
JoAnne NELSON British Columbia Geological Survey, British Columbia
37
What’s up down there? Opening the door to Stikinia’s basement
Poster 5
Near Terrace, BC, stratified rocks of Stikinia are intruded by the Early Jurassic Kleanza pluton. They are fault‐
juxtaposed to the west with the Central Gneiss Complex and Early Jurassic Shames River intrusive complex.
Farther west, the Ecstall belt is a mid‐Paleozoic arc complex intruded by Mississippian and Early Jurassic
plutons. Geological continuity across the Terrace‐Ecstall transect is demonstrated by similar igneous
geochemical signatures of Mississippian and Early Jurassic suites. Mississippian suites are silica bimodal,
showing subduction influence in felsic rocks and non‐arc immobile element signatures in metabasalts. Early
Jurassic intrusive phases show continua on modified alkali‐lime, aluminum saturation and Fe* vs. silica plots,
increasing LREE/HREE and HREE/MREE with silica, and influence of plagioclase and hornblende fractionation.
The Early Jurassic intrusions are interpreted as evolving in related magma chambers within a structurally‐
controlled permeability corridor along the terrane‐transverse Skeena arch. Middle Jurassic stratified rocks west
of Anyox at the southern end of the Eskay rift comprise basalt, rhyolite, and associated sedimentary units.
They correspond to the Iskut River Formation, the fill of the Eskay rift in the Iskut region. The Ecstall belt and
the cryptic Precambrian source of detrital zircons in the Iskut River Formation near Anyox (Evenchick and
McNicoll, 2002) are parts of the composite, pre‐late Paleozoic basement. Major long‐lived (Late Devonian to
Recent) N‐S and E‐W fault corridors in Stikinia cut across different basement components, suggesting that their
precursors formed after amalgamation of its basement, prior to the Stikine assemblage.
Graham NIXON British Columbia Geological Survey, British Columbia
Geochronology of the Turnagain Alaskan‐type intrusion and implications for Ni‐Cu‐PGE
mineralization
Co‐authors: J.E. Scheel, R.M. Friedman, C.J. Wall, J. Gabites and J.S. Scoates
Poster 7
Geochronology (U‐Pb, 40Ar/39Ar) and field mapping of ultramafic‐mafic rocks forming the Early Jurassic
Turnagain Alaskan‐type intrusion in north‐central British Columbia has established a multi‐stage history of
emplacement. Four distinct intrusive phases are recognized (from oldest to youngest): Phase 1, interlayered
wehrlite and clinopyroxenite; Phase 2, mainly dunite and wehrlite with minor clinopyroxenite and
hornblendite; Phase 3, mela‐diorite and hornblendite; and Phase 4 clinopyroxenite, hornblendite and minor
leuco‐diorite. Magmatic Ni‐Co‐platinum group element (PGE) sulphide mineralization hosted by Phase 2 forms
a subeconomic resource of 1842Mt grading 0.21wt% Ni, and Phase 4 contains additional occurrences of Cu(‐
PGE) sulphides. U‐Pb dating by chemical abrasion‐isotope dilution‐thermal ionization mass spectrometry (CA‐
ID‐TIMS) yields the following 236U/208Pb dates (±2σ) that are interpreted as crystallization ages: Phase 2
hornblendite, 190.3±4.5 Ma (titanite); Phase 3 mela‐diorite, 188.11±0.14 Ma (zircon); and Phase 4
clinopyroxenite and leuco‐diorite, 185.63±0.19 and 185.33±0.13 Ma (both zircon), respectively. 40Ar/39Ar dating
of Phase 2 wehrlite and hornblendite yield plateau ages of 188.6±1.2 Ma (2σ, phlogopite) and 187.4±1.5 Ma
(hornblende), respectively, that represent cooling ages. Thus, the Turnagain intrusion was emplaced in discrete
stages over a period of at least 3 million years (ca. 188‐185 Ma). The geochronology results rationalize the
enrichment of chalcophile elements (Cu, PGE) in the youngest Phase 4 intrusive event: evolution towards
38
sulphide saturation in Cu(‐PGE)‐enriched Phase 4 and Ni‐Co(‐PGE)‐endowed Phase 2 intrusions evidently
occurred in completely independent mineral systems.
Bruce NORTHCOTE BC Ministry of Energy and Mines, British Columbia
Exploration and Mining in Southwestern BC, 2016
Poster 17
The region's major metal mine, Myra Falls, and only coal mine, Quinsam, remained on care and maintenance in
2016. Most aggregate and industrial minerals producers remain in operation. The level of mineral exploration
in the region in 2016 was generally low, though there were a few diamond drilling projects and a number of
surface exploration programs, mainly on porphyry copper and gold vein prospects.
Andrew PARSONS Geological Survey of Canada, British Columbia
Investigating the Slide Mountain Terrane: Preliminary observations from Dunite Peak, Big Salmon
Range, south‐central Yukon
Co‐authors: J.J. Ryan and C.R. van Staal
Poster 78
Understanding of the formation of accretionary orogens requires investigations of the timing, kinematics and
mechanisms of terrane accretion. In the NW Cordillera, the Slide Mountain oceanic terrane (SMT) formed
between Phanerozoic island arcs and the North American continent (NAC) during Devonian‐Permian times and
subsequently recorded multiple deformation events during ocean closure and arc accretion. We present
preliminary findings from fieldwork in the Dunite Peak area of the Big Salmon Range, south‐central Yukon; an
area in which klippen of mafic‐ultramafic rocks belonging to SMT structurally overlie rocks that are interpreted
as island arc basement of the Yukon Tanana terrane (YTT). The allochthon / parautochthon suture between YTT
and the Cassiar terrane (CT) of the NAC has also been mapped in this region by previous workers. As such, this
area provides an excellent opportunity to study the structural relationships between multiple terranes of the
NW Cordillera. Initial findings from fieldwork and optical microscopy are presented, and include a new
geological map and lithostratigraphic framework for the area. Currently, multiple tectonic models may be used
to explain the formation and subsequent obduction and deformation of the SMT in this region. We assess
these models and propose future lines of investigation that should be undertaken in order to ascertain their
validity and applicability to the NW Cordilleran orogen.
Christa PELLETT Geoscience BC, British Columbia
Search Project: Phase II Activities in West‐Central British Columbia
39
Poster 24
The Search Project is a multi‐year Geoscience BC initiative that reveals prospective mineral areas in North
Central BC using airborne surveys. A primary objective of the project is to complete airborne magnetic surveys
with a line spacing of 250 m—creating an opportunity to formulate new geological interpretations at a
property‐scale as an aid to explorers. The regional scale of the surveys also supports the development of a
refined tectonic framework, especially in areas with poor access or low rock outcrop such as those identified in
the adjoining Geoscience BC TREK project area. It is hoped that exploration sector will use this new
information to focus or renew its efforts in discovering and developing opportunities within the province, and
communities, First Nations and governments will benefit from new geoscience data that will assist in making
informed resource‐management decisions and highlighting economic opportunities. The Search project is
planned to be completed in four phases, with the results of Phase II being released at Roundup 2017. Phase II
activities began in late June 2016, and a contract was awarded to Ottawa‐based Sander Geophysics Ltd., who
flew an estimated 105 000 line kilometres using fixed‐wing aircraft at a predetermined height and drape over
the project area. The survey followed east‐west‐trending flight lines at 250 m intervals, with north‐south tie
lines specified at 2500 m intervals. Although not identified as one of its major priorities, radiometric data was
also collected in the course of the survey.
Barry PENNER University of British Columbia, British Columbia
Structural Geometry of the Southeast Selwyn Basin: How Folded is the Selwyn Fold Belt?
Co‐authors: K. Hickey, E. Martel, L. Kennedy, and H. Falck
Poster 93
Mesozoic deformation of Selwyn Basin rocks in Nahanni, located ca. 50km northwest of Tungsten, NT, is poorly
constrained. Data collected during four months of structural transect mapping has identified kilometer‐scale
similar folding via stratigraphic repetition, mesoscopic parasitic fold vergence, and bedding‐foliation vergence
patterns. Three structural‐lithostratigraphic domains are distinguished based on complex foliation relationships
across the study area. Domain 1 is defined by four tectonic foliations overprinting bedding, two‐fold
generations, and biotite‐zone metamorphism affecting coarse sandstones and shales. This domain is not yet
correlated with the remaining two. Domain 2 is defined by one crenulation foliation (S2) axial planar to one‐
fold generation, and biotite‐zone metamorphism with localized growth of andalusite, cordierite, and rare
staurolite in coarse sandstones and shales. Domain 3 is defined by one foliation, one‐fold generation, and sub‐
chlorite zone metamorphism affecting fine shales and minor carbonates. This foliation is correlated with the S2
fabric of domain 2 along the Fork Anticline. The relative intensity of strain fabrics is consistent both regionally
and through the stratigraphic column, and no evidence for significant thrust‐related shortening is observed.
The next phase of research will focus on correlating foliations across domains, relating metamorphic
assemblages to tectonism, and developing a kinematic history for LPS in Nahanni. A kinematic history for LPS in
Nahanni will provide important constraints on the transition of strain accommodation mechanisms from the
inner to the outer Cordilleran FAT belt, and will clarify outstanding questions posed by the mineral exploration
community regarding the geometry of Nahanni rocks.
40
Jan PETER Geological Survey of Canada, Ontario
Targeted Geoscience Initiative: Research on depositional controls on volcanic‐ and sedimentary‐
hosted base metal sulphide deposits
Co‐authors: Michael G. Gadd, Daniel Layton‐Matthews, Matthew I. Leybourne, Nigel Bocking, Simon Jackson,
Ming Liu, Madison Schmidt, Daniel Kontak, Beth McClenaghan, Bruce E. Taylor, and Nicholas Johnson
Poster 70
This project is focused on four areas:
1) Evaluation of the relative roles of anoxia (no O2 in the water column), euxinia (H2S in the water
column) and microbes in SEDEX and VSMS deposit formation. The long‐standing exploration model for these
deposits is that reduced (organic matter‐rich and pyritic) sediments are a key requisite (as an inhibitor of
destructive seafloor oxidation in the case of VSMS), as is the involvement of microbes in the water column.
2) Genesis of metalliferous shale deposits, an important global resource for Zn‐Ni‐Cu‐Mo‐Se‐U‐V ± Cr‐
Co‐Ag‐Au‐PGE and REE. Genetic and exploration models are myriad, with interpreted sources of metals
including seafloor hydrothermal, ambient seawater/phosphogenesis/high organic productivity and extra‐
terrestrial. There is significant potential for the further discovery and development of such deposits in Canada,
but the lack of consensus on genetic controls hinders exploration.
3) Evaluation of direct magmatic contributions of metals and volatiles to VMS deposits. Fluid inclusion
salinities are mostly substantially greater than seawater. Various mechanisms have been proposed to explain
these values, including direct contribution of a saline magmatic fluid. For some deposits, there are other
indicators (e.g., “magmatic suite” trace metals; S, H, O stable isotopic; radiogenic Pb isotopes; aluminous
alteration assemblages) that provide supporting evidence of a magmatic contribution.
4) Evaluation of the utility of non‐traditional size fractions of indicator minerals (e.g., <0.25 mm) in VMS
as a record of fluid‐rock interaction and their potential use in exploration.
Yuliana PROENZA Apex Geoscience Ltd., British Columbia
Direct‐use Geothermal Resources in British Columbia
Co‐author: Catherine Hickson
Poster 23
A follow‐on project to carry out recommendations from Report 2016‐07
(http://www.geosciencebc.com/s/Report2016‐07.asp) was undertaken during August to December 2016. The
recommendations were to raise awareness of Direct‐use development possibilities in BC and interact closely
with communities (including First Nations) to provide guidance as to the value and variety of Direct‐use
geothermal applications. Educational activities for the general public and to school educators were also
developed.
A total of 83 communities in BC were provided with the results and 29 communities participated
actively to learn and evaluate possible next steps. A one day workshop was organized in Agassiz, BC, a
41
presentation was given to the Northeast BC Resource Municipalities Coalition Forum in Fort St. John and a
delegation presentation was delivered to the Board of Directors of the Thompson‐Nicola Regional District.
These activities engaged 20 communities and more than 10 electoral areas.
Challenges were encountered to actively involve other communities and so bridging material was
developed. An introductory webinar is currently being developed with BC Economic Development Division to
be delivered winter 2017. Other steps included the development of a website resource portal, a Twitter
account (www.twitter.com/BCGeoHeat) and the recording of eight modules in webinar format that are
available on the website (www.bcgeoheat.com). Collaborations with Northern Lights College, BCIT and
Thomson Rivers University will provide project results for post‐secondary and continuing education students.
In addition to community interaction, a proposal for Carbon Tax Credits and incentives for Direct‐use
Geothermal Investments was developed as a way to encourage communities to develop Direct‐use projects.
Mana RAHIMI Mineral Deposit Research Unit, University of British Columbia, British Columbia
Multi‐Depth Structural Interpretation of Western Skeena Arch Using SeArch Phase 1 Aeromagnetic
Data, west‐central BC
Co‐authors: Joel J. Angen and Craig J.R. Hart
Poster 32
Identification of the structural framework is critical to mineral exploration and geological mapping of any area.
An advanced method for interpretation of gridded magnetic data has been applied to interpret and visualize
newly‐acquired SeArch geophysical data as an important source of information for identifying lineaments and
subsurface structures. The method provides an effective approach to identify the fault systems that affect the
source rocks and control fluid flow in mineralized areas.
The Skeena Arch is a northeast‐trending geomorphological belt of dominantly Jurassic rocks located in
west‐central BC. The SeArch project area spans two mineral‐rich geological terranes, covering 6755.6 km2
within the western Skeena Arch.
A structural framework is derived from aeromagnetic structural interpretation using Advanced Edge
Detection techniques (AED). A variety of different derivative layers of the magnetic data such as analytical
signal, vertical derivative, total horizontal derivative and tilt derivative (Ferreira et al., 2011; Verduzco et al.,
2004) were considered. As well, the Multi‐scale Enhanced Edge Detection method was applied to identify
shallow, mid‐depth and deep structures. The method provides the information on the 3D orientation of
structures based on the maximum horizontal gradient in potential‐field anomalies and upward continued
levels. The results were interpreted and evaluated through comparison with available datasets to aid in
understanding the tectonic trends of the area and potential structural constraints on mineralization.
The identification of aeromagnetically‐defined structural zones clarifies the type, series and the depth of
structures in different geological domain in the SeArch area which can advanced targeting for high‐probability
mineralized regions.
Abdul RAZIQUE University of British Columbia, British Columbia
42
Anatomical Variation of the Hydrothermal Alteration at Reko Diq Western Porphyry Copper‐Gold
Complex, Balochistan, Pakistan
Co‐authors: Richard Tosdal and Farhad Bouzari
Poster 60
The Reko Diq western porphyry complex in Chagai belt, Balochistan Pakistan host a cluster of porphyry copper‐
gold deposits containing a significant geological resource of 5.9 Gt @ 0.41% Cu and 0.22 g/t Au. Magmatic‐
hydrothermal activity result in the formation of four distinct porphyry centers including H79, H15, H14 and H13
developed from north to south. These porphyry centers are roughly 1‐km apart and are spatially and
temporally associated with late‐Miocene (13‐12Ma) calc‐alkaline porphyry intrusions hosted by Oligocene
andesitic volcanic and clastic sedimentary rocks.
The porphyry intrusions are characterized by phenocrysts of plagioclase feldspars, quartz, biotite, and
minor amphibole in a microcrystalline groundmass. The multiphase overlapping porphyry intrusions are
accompanied by sodic‐calcic, potassic, sericite‐chlorite, phyllic, and propylitic alteration assemblages
introducing distinct alteration patterns and variation between the adjacent porphyry centers. The early
porphyry intrusions are overprinted by intense potassic alteration of hydrothermal biotite – K feldspar ‐
magnetite ± anhydrite with associated quartz A‐ and B‐type veins and sulfide mineralization. The H79 complex
in the north and the H13 complex to the south are intruded by late dacite porphyry intrusions leading to
formed smaller donut‐shaped ore bodies. The central H14 complex has well‐preserved potassic alteration and a
distinct high‐grade bornite core. In contrast, potassic alteration in the older H15 complex is largely overprinted
by sericite‐chlorite alteration assemblage where bornite is less in volume to chalcopyrite. The hydrothermal
fluids in H15 complex appear to have evolved to high‐sulfidation sulfide mineral assemblages of pyrite‐
covellite‐bornite‐chalcopyrite and associated quartz‐sericite alteration restricted to vertical narrow zones and
stratabound horizons.
The sodic calcic alteration of albite‐epidote ± actinolite ± chlorite at depth > 1‐km overprint potassic
alteration assemblages. The cream‐white albite replaces K‐feldspar and epidote replaces plagioclase and
actinolite or chlorite replaced igneous mafic silicates. The potassic and sodic‐calcic alteration at deeper levels
are deficient in sulfides and contain less than 1% chalcopyrite ± pyrite. The potassic alteration assemblages at
shallow depths in all porphyry centers are overprinted by sericite‐chlorite and superimposed by intermediate
argillic alteration of illite‐smectite assemblages. The outer phyllic alteration zone is characterized by pale‐white
quartz, fine‐grained sericite (muscovite), abundant pyrite, and traces of chalcopyrite overprinted by kaolinite
and montmorillonite. Peripheral volcanic and sedimentary rocks around the western porphyry complex are
characterized by intense propylitic alteration of chlorite‐epidote ± pyrite‐carbonate assemblage. The youngest
and late mineral porphyry intrusions are volumetrically smaller and form narrow low‐grade core in each
porphyry deposit at western Reko Diq.
Andrea REMAN University of Waterloo, Ontario
Towards a 3D Quaternary and Neogene Stratigraphic Model of the Highland Valley Copper Mine
Area, South‐Central British Columbia
Co‐authors: Martin Ross and Robert Lee
43
Poster 62
The study of sediment successions that partly or completely cover known mineralization can help understand
the masking or dispersing effect on geophysical and geochemical properties. Highland Valley Copper (HVC), a
large porphyry Cu‐Mo system located in British Columbia, is partially covered by more than 200 meters of
Quaternary and Neogene sediments. Till geochemistry and indicator minerals have recently been identified at
surface and traced back to their shallow mineralized source. However, we know little about the composition
and physical properties of the sediment cover directly overlying the more deeply buried mineralized zones.
The goals of this research are to 1) define the three‐dimensional sediment stratigraphy at HVC, 2) investigate
the physical properties of the main subsurface units to constrain geophysical inversions, 3) identify mineral
indicators and geochemical pathfinders throughout the successions and establish their provenance, and 4)
determine the depositional processes of sedimentary units.
The methodology focuses on a facies analysis and stratigraphic correlation of nine sonic drillcores at
depth ranging from 124 to 242 metres. Petrophysical properties (magnetic susceptibility, chargeability and
porosity) will be used to characterize the main units. Provenance will be determined based on the lithology of
pebbles, heavy minerals and the geochemical makeup of the silt and clay fraction. The provenance study will
also include identification of possible signature of the buried mineralization and alteration in the sediment
cover. Preliminary results suggest complex stratigraphic architecture with lateral facies transitions, as well as
depositional units of variable spatial extent.
NSERC‐CMIC Footprints Exploration Project Contribution #117
Alexei RUKHLOV British Columbia Geological Survey, British Columbia
Apatite compositions as a proxy for the oxidation states of porphyry Cu‐Mo‐Au deposits
Co‐authors: Stephen M. Rowins, Mao Mao, Laurence A. Coogan, and Jody Spence
Poster 13
A wide range of oxidation states characterize magmatic‐hydrothermal systems that form porphyry Cu‐Mo‐Au
deposits. High oxidation states are recognized as an important factor in the genesis of giant porphyry systems,
but the wide range of oxidation states that accompany porphyry formation indicates that the role of oxygen
fugacity in the ore‐forming process is complex. Previous studies have shown that concentrations of multivalent
elements S, V, Cr, Mn, Fe, Ga, As, Ce, and Eu in apatite can be used as redox sensors in magmas and fluids. Here
we follow up the utility of apatite chemistry as a redox proxy using both new and published electron
microprobe (n = 650) and laser‐ablation inductively coupled plasma mass spectrometry (n = 712) data from five
Neoarchean monzonite‐syenite plutons of the southern Abitibi belt and twenty porphyry Cu‐Mo‐Au deposits
with oxidation states ranging between ΔFMQ = ‐3 to +3, based on independent estimates from petrologic
buffers. Apatites from reduced, ilmenite‐bearing, calc‐alkaline porphyry systems (e.g., Catface, North Fork, San
Anton, Troilus) have much lower S, V, and Eu contents than those of oxidized monzonite‐syenite intrusions and
alkalic porphyry Cu‐Au systems (e.g., Mount Polley, Redgold, Dobbin). Apatites from oxidized, magnetite‐
bearing, calc‐alkaline porphyry Cu±Mo±Au (e.g., Kemess, Highland Valley) and porphyry Mo (e.g., Boss
Mountain, Endako) systems have intermediate contents of these elements. These elements in apatite appear
to correlate with the oxidation state of the magmas. Concentrations of Mn, As, and Ce vary up to three orders
of magnitude between individual deposits suggesting additional controls of their behavior.
44
Jim RYAN Geological Survey of Canada, British Columbia
Preliminary geological map of the Klaza River area, west‐central Yukon
Co‐authors: Steve Israel, Andrew Parsons, Nathan Hayward and Stephen Williams
Poster 79
Mapping in the Klaza River area in 2016 improved on reconnaissance work completed in the 1970’s, and
extends new published mapping in the Mount Nansen – Nisling River area (carried out in 2015) immediately to
the southeast. Mapping was greatly assisted in this area of variable quality of bedrock exposure by recently
acquired 400 m line spacing aeromagnetic data. Many of the older, more deformed and metamorphosed rocks
in the area correlate to established units within Yukon‐Tanana terrane, dominated by Snowcap assemblage
siliciclastic rocks composed mainly of quartzite, micaceous quartzite and psammitic quartz‐muscovite‐biotite (±
garnet) schist. Igneous lithologies characteristic of Yukon‐Tanana terrane are generally restricted to area’s
easternmost extent. Two major mid‐Cretaceous granitic batholiths dominate the area and are divided into the
Dawson Range batholith (DRB) in the north, characterized by blocky hornblende bearing granodiorite, and the
Maloney Creek batholith (MCB) in the south, characterized by monzogranitic composition, light smoky quartz
phenocrysts, and higher abundance of biotite.
We discriminate mid‐Cretaceous to Tertiary volcanic and hypabyssal rock sequences in the area in
order to better understand their map distribution, and potential for mineralization (e.g., the Late Cretaceous
Casino Suite). This task is complicated by similarities in appearance and character amongst these units. Our
mapping clarifies a sequence of volcanic and hypabyssal rocks in the northern part of the area, and correlates
them with the mid‐Cretaceous Mount Nansen group volcanic rocks, rather than with the early Late Cretaceous
Open Creek volcanics, as currently exhibited on regional maps.
Dave SACCO Palmer Environmental Consulting Group, British Columbia
Identifying Mineral Exploration Targets in the TREK Project Area, Central British Columbia (parts of
NTS 093B, C, F, G), using a Multimedia and Multivariate Analysis of Geochemical Data and a
Preliminary Method of Sediment Transport Modelling
Co‐authors: Wayne Jackaman, Ray Lett, and Brodie Elder
Poster 39
Geoscience BC’s Targeting Resources through Exploration and Knowledge (TREK) project has produced a
comprehensive collection of geoscience information for a highly prospective area in central British Columbia.
Up to this point, the surficial geochemistry component of the project has focused on new till and lake sediment
sampling combined with a reanalysis and genetic interpretation of similar archived data, resulting in one of the
largest, high‐quality, and directly comparable surface sediment exploration datasets in North America. This
value‐added project provides advanced processing of the TREK geochemical data that incorporates a bedrock
45
and surficial context into the evaluation to better understand the complex nature of this information.
Exploration targets will be identified through a multimedia and multivariate analysis that highlights samples
with geochemical signatures similar to specific common deposit types. In addition, a method to delineate
potential source regions, or areas of influence (AOI), for till and lake sediment samples will be developed and
tested. A catchment basin analysis will be used for the lake sediment samples. Till sample AOI will be
delineated using ice‐flow data and known sediment transport distances. Till AOI are designed to spatially
associate till samples to a dominant bedrock source unit. This association will be used to level the till
geochemical data and mitigate the influence of contrasting rock types on the regional till geochemical dataset,
which should improve anomaly identification. The overarching goal of this project is to increase exploration
activities in the TREK project area by identifying new exploration targets.
Jeffrey SALVADOR University of Calgary, Alberta
Crystal Chemistry and Structure of Anomalous Birefringent Cubic Uvarovite Garnet, Ideally
Ca3Cr2Si3O12
Co‐author: Sytle Antao
Poster 56
Extensive research on the anomalous birefringence phenomenon of the garnet group of minerals still continues
to be the focus and interest of many geoscientists today. Previous studies from over a century of investigations
attribute the occurrence of optical anisotropy mostly but not limited to, cation ordering on the dodecahedral
{X} and octahedral [Y] sites, lattice mismatch at compositional boundaries caused by strain, and from the
presence of hydrous components within the tetrahedral (Z) site. However, the origin remains debatable and is
still unclear. Uvarovite, a rare mantle‐derived garnet, ideally, Ca3Cr2Si3O12, is the least studied silicate end‐
member species. Under crossed‐polarized light, this beautiful emerald‐green mineral displays distinct
birefringence of 0.001‐0.006 with some crystals exhibiting additional anisotropic features revealing a sectored
‘bowtie’ structure with well‐defined extinction positions. Birefringent uvarovites from Finland, California,
Russia, and Switzerland are the focus of this study. Using electron probe microanalysis (EPMA) and synchrotron
high‐resolution powder X‐ray diffraction (HRPXRD) further reveals the correlation of the anomalous
birefringence in relation to crystal chemistry and structure. Our results are consistent with other anisotropic
garnets analyzed with EPMA and HRPXRD, further supporting the cause of anomalous birefringence in
uvarovite garnets, as derived from strain closely related to crystals containing the existence of secondary cubic
uvarovite phases consisting of slight variations in chemical compositions.
Ernst SCHETSELAAR Geological Survey of Canada, Ontario
Integrated 3D model of the magmatic‐hydrothermal evolution of the New Afton alkaline porphyry
deposit, British Columbia, Canada.
Co‐authors: Gilles Bellefleur, Jim Craven, Don White, Mike Thomas, Victoria Tschirhart, Mark Pilkington, Randy
Enkin, John Percival, Jean Percival and Neil Rogers
46
Poster 67
The Geological Survey of Canada’s Targeted Geoscience Initiative is developing an integrated geophysical
imaging and 3D geological modelling research study of the New Afton porphyry deposit located in the Canadian
Cordillera of south‐central BC. This alkaline Cu‐Au porphyry deposit previously supported an open pit operation
and is currently being mined at deeper levels through underground workings, providing geological constraints
extending beyond 1.5 km in depth. This study intends to combine new vertical seismic profile (VSP) and 3D
magneto‐telluric (MT) surveys, along with multi‐parameter deep drillhole geophysical logs, and 3D modelling to
elucidate the magmatic hydrothermal processes and structural controls responsible for concentrating metals in
porphyry deposits. A 3D drillcore database compiled from new and existing geological, geochemical and
petrophysical data that will calibrate and validate 3D qualitative and quantitative interpretations of the
proposed VSP and MT surveys, resulting in an internally self‐consistent multi‐parameter 3D model. A
complementary activity is planned to integrate magnetic, geochemical and magnetite microprobe analyses to
gain insight into the magmatic and hydrothermal evolution of the porphyry deposit. The multi‐parameter 3D
model of the deposit will be interpreted in the context of deep crustal architecture and magmatic sources to
constrain the role of mid‐ to deep crustal tectonomagmatic processes in the formation of porphyry
mineralization.
Paul SCHIARIZZA British Columbia Geological Survey, British Columbia
Continuing stratigraphic studies in the Nicola Group: Stump Lake ‐ Salmon River area, south‐central
British Columbia
Poster 6
The Nicola stratigraphic framework project, initiated in 2015, was implemented to provide a regional‐scale
stratigraphy for the Nicola Group (Triassic), the defining supracrustal element of the Quesnel arc terrane in
southern British Columbia. The 2016 mapping program covered the eastern part of the Nicola belt southeast of
Kamloops, between Stump Lake and the Salmon River. Here, the Nicola Group is subdivided into 3 units, which
show strong similarities to 3 of the 4 assemblages established to the north, in the Bridge Lake – Quesnel River
area. Most widespread is the volcanic sandstone unit (assemblage two), comprising plagioclase‐pyroxene
sandstone, locally intercalated with volcanic conglomerate or siltstone. The pyroxene basalt unit (assemblage
three), overlies the volcanic sandstone unit in the western part of the area, and consists of massive pyroxene
(±plagioclase±hornblende)‐phyric basalt and associated breccias. The polymictic conglomerate unit
(assemblage 4) comprises conglomerate with a distinctive clast population that includes mafic plutonic rocks. It
overlies the volcanic sandstone unit in the eastern part of the area, across a contact that is suspected to be a
significant disconformity. The Salmon River unit, Triassic conglomerate, calcareous sandstone, and siltstone,
occurs east of the Nicola Group, where it overlies Paleozoic schists of the Chapperon Group across a well‐
defined angular unconformity. Although not included in the Nicola Group, it might form an eastern
sedimentary facies that underlies or interfingers with the group.
Elizabeth SHARMAN Mineral Deposit Research Unit, University of British Columbia, British Columbia
47
Constraining Metal and Magma Sources and the Provinciality of Cordilleran Porphyry Systems: The
BC Pb Isotopic Advantage
Co‐authors: Craig J.R. Hart, Janet Gabites, James Mortensen, and Colin Goodwin
Poster 51
Economically significant Late Triassic to Early Jurassic porphyry Cu±Mo±Au systems in BC have a wide range of
associated magmatic rocks, oxidation states, metal types and sizes, and preferentially form in certain districts
or belts in Quesnellia and Stikinia. While magmatic and hydrothermal process are ultimately responsible for
ore deposition, the source of the magmas, metals and sulphur are likely key constraints to their provinciality,
endowment and metal character. Although geodynamic models have been proposed, there is little hard data
that constrains the nature of the lithospheric melt sources and their modifications that reflect tectonic
geometries, and evolution as they migrate through the crust. Lead isotopes have long been recognized as
robust indicators of signatures of various lithospheric and crustal influences, as well as constraining potential
metal reservoirs in ore systems, and will be the primary tool utilized in this study. This research will bring
forward and update the Leadfile (BCGS Paper 1988‐2) with data in publications and lost in theses. With the
new robust dataset, it will be queried, geographically, geologically, and with respect to plutonic suites and
metal tenor of the ore systems in question to determine trends and patterns that contribute to magmatic
evolution of the Late Triassic to Early Jurassic arcs.
Clinton SMYTH Georeference Online Ltd., British Columbia
Using Hyperspectral Core Imaging to distinguish Important Mineral Alteration Assemblages within
the Big Bulk Porphyry Gold/Copper System at Kinskuch Lake, British Columbia
Poster 52
Changes in mineral alteration assemblages within and around mineralised porphyry systems can provide
powerful vectors towards the best‐mineralised zones within those systems. These changes are often very
subtle, gradational, and not discernable by the human eye. Hyperspectral scanners can, however, detect these
changes, and, when systematically deployed on drill core, provide semi‐quantitative mappings of the degree of
change from top to bottom of a drillhole.
This poster presents the results and interpretation of automated TerraCore Hypespectral scanning of
drill core from the Big Bulk Copper Gold Porphyry System in British Columbia’s Golden Triangle.
A workflow is demonstrated for managing the large volume of digital information generated by such core
scanning, and for integrating that information with other sources of data. The hyperspectral information is
used to show that a high‐grade copper / gold intersection near the top of a drillhole at Big Bulk is accompanied
by a higher temperature alteration assemblage than a lower grade intersection deeper in the hole – differences
which have important exploration implications, but which were not observed by the original loggers of the
borehole.
Carl SPENCE‐JONES University of Leeds, UK
48
Evaluation of trace elements in gold by LA‐ICP‐MS: preliminary results of placer‐ lode studies in
British Columbia
Co‐authors: Robert Chapman and David A. Banks
Poster 33
The elements present in natural gold have commonly been determined by electron microprobe (EMP), but the
high detection limit of this method limits those that can be quantified. Laser ablation‐ inductively coupled
plasma‐ mass spectrometry (LA‐ICP‐MS) can provide quantitative analyses for a much greater number of
elements to sub‐ppm levels. Here we present the results of two initial studies where the enhanced range of
elements detectable by LA‐ICP‐MS has been applied to the potential use of gold as an indicator mineral for the
style of source mineralization.
Our new results reveal that detrital gold derived from the alkalic porphyries of Mt Milligan, Copper
Mountain and Afton exhibit a very similar trace element signature. Previously EMP studies revealed the
significance of elevated Pd and Hg in the Au alloy, but the full concentration range of these elements, (at much
lower concentrations), is now available for consideration together with new data sets for Cd, Sb and Cu. All
these elements are present at much higher concentrations than in gold from the orogenic mineralization near
Wells.
Previous gold compositional studies around Wells identified two gold populations on the basis of the
Ag content and inclusion assemblage. The range of Ag in these two types overlapped, which in some cases
impeded clarification of placer‐ lode relationships. Trace element signatures obtained by LA‐ICP‐MS have
provided a better distinction between the gold types, such that the importance of one type is now seen to be
much greater than originally believed.
Jessica STROMBERG University of Western Ontario, Ontario
Fingerprinting Early Gold Mineralization in the Timmins Gold Camp: Trace Element and Isotope
Geochemistry of the Dome Mine Ankerite Veins
Co‐authors: Erik Barr, Lisa L. VanLoon, and Neil R. Banerjee
Poster 43
The Dome mine in Timmins, Ontario has produced over 16 Moz of gold to date, with ~20% mined from its
ankerite veins. Early carbonate veining is common across the camp and represents the onset of a multi‐stage,
~10‐25 Ma mineralization history resulting in an over 100 Moz gold endowment. A mine to micron approach,
combining conventional geochemical techniques with in‐situ high resolution trace element analysis of ore
minerals was used to fingerprint the mineralization history of and develop a model for ankerite vein formation
and their role in the world class gold endowment at the Dome.
Trends in ankerite δ13C and delta δ18O values, and REE contents provide evidence for fluid flow
direction and source, indicating that the Northeast striking ~100m wide Dome fault deformation zone likely
acted as a conduit for ankerite‐forming early metamorphic fluids. Gold across the deposit (and camp) is
intimately associated with pyrite mineralization. Three distinct fluid events have been identified based on
49
pyrite growth history, trace element geochemistry and gold content. The early syn‐ankerite gold event is
enriched in metals and metalloids such as Cu, As, Zn and Ni with respect to the main stage mineralization which
contributed the bulk of the gold to the system. This enrichment may be related to previously undescribed local
lenses of massive sulphide in the Tisdale Assemblage volcanics and is followed by an Ni‐rich, Au remobilization
event before main stage quartz vein hosted gold mineralization.
Taija TORVELA University of Leeds, UK
Structural interpretation of the Nadaleen Trend, Yukon
Co‐authors: Cristina Accotto and Flora Elliston
Poster 97
The Nadaleen Trend in eastern Yukon hosts Carlin‐type gold deposits. The deposits are found in the northern
margin of the Selwyn Basin and are structurally controlled, associated with known fault systems. This poster
presents the key findings of two MSc student projects, completed in summer 2016 at the University of Leeds,
United Kingdom. The poster looks into both deposit‐scale and regional structural trends of this part of the fold‐
thrust belt, and the relationships of the structures to the gold occurrences. Both balanced cross sections and
deposit‐scale 3D modelling were used to attain an understanding of the relationships between the palaeobasin
configuration, fold‐thrust belt related structures, and ore mineralisations.
The studies imply a strong structural control of the ores by faults, the location and geometries of which
may in turn be controlled by the configuration of the palaeomargin, specifically the location and geometry of
the Ogilvie Platform ‐ Selwyn Basin transition. The underlying inherited structure contributed to the present
structural complexity, which probably facilitated and focused fluid flow into this specific area. There are, in
addition, indications of possible local extensional/transtensional structures in the structurally complex zone,
occurring within the overall compressional orogenic regime: these anomalous structures may have also played
an important role for the localization of the ore.
Pim VAN GEFFEN REFLEX, British Columbia
Clay‐Fraction Till Geochemistry of the TREK Project Area, Central British Columbia (Parts of NTS
093B, C, F, G)
Poster 26
Large parts of central British Columbia (BC) are underexplored because of extensive Quaternary cover that
obscures much of the underlying geology from direct observation. As a result, exploration efforts face
increased risk and must rely on indirect detection of mineralization by geophysical or geochemical methods. As
these methods evolve and improve over time, integration of the various data types increases confidence in the
understanding of the bedrock lithology and mineralization potential. Geoscience BC has funded several
campaigns across their TREK project area in central BC. The size fraction that was selected for the till
geochemistry in this project was <63 µm (silt + clay). Although this is standard practice in till analysis because
50
dry sieving to a finer fraction would be impractical, the geochemical response may still be overwhelmed by
matrix components such as carbonate minerals and organic matter. To remedy the effect of matrix materials
on the till analysis and reduce its heterogeneity, the clay‐sized fraction (<2 µm) can be extracted and analyzed,
which has been known to provide superior results for trace elements transported by hydromorphic dispersion
through the till cover. The results presented here are multi‐element data generated from the clay fraction of a
subset of the TREK tills by aqua‐regia digestion and ICP‐MS analysis.
Colton VESSEY University of Saskatchewan, Saksatchewan
North American Cordillera reconstruction; an example for a new method of viewing regional
geology and mineral exploration
Co‐author: Bruce Eglington
Poster 92
The North American Cordillera is a complex accretionary system that has been extensively mapped since the
early 1900’s, leading to conceptual models for relative motion of many of its constituent blocks. The region is
host to numerous significant mineral occurrences and deposits, including: volcanogenic hosted massive sulfides
(VHMS), Mississippi valley type (MVT), clastic Pb‐Zn/ SedEx, and a variety of porphyry deposits. Variable
geodynamic settings and changes throughout the Phanerozoic have produced a variety of depositional and
magmatic environments, leading to this diverse range of mineralisation. Current approaches to displaying
changes have been quasi‐static with most geological representations presented in the context of their present‐
day location or as schematic illustrations of past geologic plate locations. Here, we attempt to illustrate the
geological evolution in a systematic, progressive context of continually varying time with plate motions. To
achieve this, we draw on information from a series of structured databases which facilitate compilation of data
in a uniform manner with easy updating, querying and extraction. Current data utilized includes:
lithostratigraphy, ore deposits, geochronology, lithogeochemistry, isotope geochemistry, palaeomagnetic pole
data, plate polygons and a rotation model. Map information and polygons representative of the geology have
been taken from the provincial and state regional maps for British Columbia, Yukon and Alaska. The data
systems used were initially developed as part of the IGCP 509 and 648 projects. The plate reconstruction model
(Palaeoplates) is based on schematic geological interpretations produced by professionals in these areas and
conceptual formation of oroclines within the accretionary collage.
Stephanie WAFFORN University of Texas at Austin, USA
Andradite Garnet U‐Pb Geochronology of the Big Gossan Skarn, Ertsberg‐Grasberg Mining District,
Indonesia
Co‐authors: S. Seman, J.R. Kyle, D.F. Stockli, and M. Cloos
Poster 41
51
The Big Gossan skarn is located in the prolific Ertsberg‐Grasberg mining district, on the island of New Guinea in
Indonesia. Despite its relatively small size, Big Gossan has the highest ore grades in the district (71 million
tonnes at 2.39 wt% Cu and 0.91 ppm Au, assuming a 1 wt% Cu cutoff grade). Big Gossan was emplaced into the
steeply upturned southern limb of the Yellow Valley Syncline near the conformable contact between the Ekmai
sandstone and Waripi dolomitic limestone. Previous attempts to constrain the timing and duration of ore
formation at Big Gossan have been limited to two phlogopite 40Ar/39Ar cooling ages (Prendergast et al., 2005).
A novel technique developed at UT Austin directly dates andradite garnet using the LA‐ICP‐MS method. Seven
garnet samples were selected for analysis, and the results show that the Big Gossan skarn formed at 2.8 ± 0.1
Ma. The BG240W‐06 sample was dated three times over a six‐month period, and the age consistently
overlapped at 2.75 ± 0.03 Ma (n=150 spots) (lower intercept age, Tera‐Wasserburg concordia). This precision
was achievable due to the high U contents (10‐100 ppm) and consistent common Pb composition of Big Gossan
garnets. These ages are compatible with the district‐wide zircon U/Pb geochronology and the phlogopite 40Ar/39Ar ages. The new garnet ages show that Big Gossan was one of the last ore‐forming events in the
Ertsberg‐Grasberg district, and the maximum duration of skarn formation was 100 ‐ 200 kyr.
Nadia YAVORSKAYA GIS of NADia Geochemical Services, Manitoba
A cost‐effective way to evaluate mineral resources in covered prospects – a little known use of
surficial geochemistry
Poster 28
This is a rapid and cost‐effective method that allows pre‐drilling estimation of the amount of mineral resources
in a hidden deposit by using surface sediment geochemical data. The technology is based on contrasting signals
between background and mineralization. This technique serves as a substitute for drilling in the early stages of
mineral exploration. It permits prediction of the amount of metal in a mineralized zone.
Multi‐stage ore‐forming geological processes are reflected in different ranks of multi‐element
dispersion trains. In general, highly productive ore systems are characterized by structured geochemical ranks.
Each ore‐forming stage provides different elements for concentration on local geochemical barriers, which are
reflected in the different ranks of anomalous geochemical fields (AGF). As a result, a specific ore body is
characterized by a specific rank of AGF. The calculations for prospect resource evaluation take into
consideration rank characteristics and estimation criteria as well as contrast and size of the defined AGF.
This technology has been successful in discovering buried deposits of gold, base metals and PGE in the
low‐lands and rugged terrains of Russia and Peru. A case study of lode gold exploration in Eastern Siberia is a
typical example of an application of this predictive technique for pre‐drilling resource estimation, which is
supported by follow‐up reserve calculations during the pre‐feasibility study. This predictive exploration
geochemistry method may be of interest to junior exploration companies with limited budgets who can apply
geochemistry rather than drilling in the early stages as a mineral deposit discovery tool.
Ron YEHIA MYAR Consulting, British Columbia
52
Rapid, Field‐Based Hydrogeochemical‐Survey Analysis and Assessment of Seasonal Variation Using
a Field‐Portable Photometer and Voltammeter, Marmot Lake NTS Area, South‐Central British
Columbia (NTS 093B/13)
Co‐authors: Ray Lett and Dave Heberlein
Poster 38
Building on the successful outcome of a 2014 Geoscience BC project (Report 2015‐17) this project aims to build
on the wealth of data available in the TREK project area. It extends the real‐time hydrogeochemical‐survey
methodology to a regional setting while at the same time investigating the effects of seasonal variation. Stream
water samples were collected and analysed in an area immediately southwest of Nazko, BC. Much of the study
area is covered by Quaternary glacial deposits. Underlying bedrock consists of widespread Tertiary basalts
(Endako Group) overlying older volcanic and sedimentary rocks belonging to the early to middle Cretaceous
Skeena Group and middle to late Jurassic Hazelton Group., One hundred and fifty four water samples were
collected and analyzed at Nazko during three sampling campaigns in June, August and October 2016. Nineteen
duplicate samples were sent to an ALS Environmental laboratory in Burnaby, BC for analysis of cations and
anions. A suite of cations and anions were analysed for by portable photometer and electrochemical
voltammeter. Results show a good correlation between field and laboratory analyses with acceptable levels of
accuracy and precision. Anomalous values for Cu and As were detected in streams draining two known mineral
occurrences.
Alex ZAGOREVSKI Geological Survey of Canada, Ontario
Geological relationships in ophiolitic rocks of the northern Cache Creek terrane: GEM 2 Cordillera
Co‐authors: M.G. Mihalynuk, N. Joyce, S. McGoldrick, J.H. Bedard, D. Canil, and A‐S. Corriveau
Poster 74
Structurally dismembered, Penrose‐style ophiolite components are well exposed in the King Mountain area
where they exhibit boninitic chemistry. Nakina Formation basalt and related hypabyssal rocks, the upper
crustal component of the ophiolite, are predominantly exposed further to the northwest, such as in the Nahlin
Mountain‐Nakina Atlin and Teslin areas immediately above Nahlin suite ultramafic rocks. This lack of lower and
middle ophiolitic crust distribution suggests removal by structural excision along an intra‐oceanic detachment
zone, well known in intra‐oceanic core complexes. Ophiolitic spreading appears to have been accommodated
magmatically in the southeast and tectonically in the northwest . Such a relationship may result from
progressive rifting of a supra‐subduction zone ophiolite, with initial rifting accommodated magmatically in the
King Mountain area ac ca. 255 Ma and tectonically in Atlin‐Jake’s Corner area at ca. 245 Ma.
Re‐evaluation of tectonic relationships indicate that the Cache Creek terrane contains at least two terranes. In
the Mt. Nimbus area, ophiolitic rocks are thrust over Mississippian limestone that is interbedded with ocean
island basalt. Even though it may have been reactivated, this thrust demarcates the suture between upper
plate arc rocks (ophiolite) and subducting plate (limestone platform). In the Jubilee Mountain area, the same
juxtaposition is preserved: an isolated klippe of ultramafic rocks intruded by gabbro structurally overlies
Horsefeed Formation limestone. Identification of such suture localities is critical for unravelling the tectono‐
53
stratigraphy of the northern Cache Creek terrane as it is the primary contact in the thrust stack that was later
reworked by D2 folds and thrusts and younger strike slip faults.
Alex ZAGOREVSKI Geological Survey of Canada, Ontario
Late Triassic calc‐alkaline magmatism in northern Stikinia: GEM 2 Cordillera
Co‐authors: M.G. Mihalynuk, N. Joyce, R. Friedman, and D. Milidragovic
Poster 75
The Late Triassic Stikine plutonic suite in Yukon is limited to small‐volume plutons, such as the Tally Ho gabbro
(ca. 214 Ma) and cumulate Pyroxene Mountain Suite (ca. 218 Ma). Paucity of Stikine plutonic suite in Yukon is
partly due to latest Triassic exhumation and erosion of the Stuhini‐Lewes River arc as evidenced by an
abundance of ca. 210 Ma detrital zircon in the upper Lewes River and Laberge groups and in Late Triassic to
Early Jurassic siliciclastic rocks that overlap or are intercalated with the Cache Creek terrane. In British
Columbia, the Stikine plutonic suite comprises calc‐alkaline, diorite to monzogranite plutons. Reconnaissance
work on the Stikine plutonic suite in the Tatsamenie Lake and Atlin areas revealed a compositional diversity of
magmatic rocks that range from gabbro to monzogranite and yield U‐Pb crystallization and Re‐Os
mineralization ages ranging from 229.7 to 217.06 Ma. Based on age constraints, mineralogy and texture, the
Stikine Plutonic Suite can be divided into three broad units dominated by quartz diorite, granodiorite and
monzogranite (lTrSd, lTrSgd and lTrSmz, respectively). lTrSd is restricted to the Sheslay area, where it hosts
porphyry‐style mineralization at the Star Cu‐Au deposit (229.7 Ma quartz diorite). lTrSgd and lTrSmz are much
more wide‐spread and are coeval with felsic volcanic rocks.
Alex ZAGOREVSKI Geological Survey of Canada, Ontario
Mid‐Cretaceous magmatism in Yukon: inferences on magmatic sources and implications for the
tectonic setting of high flux magmatic episodes
Co‐authors: J.J. Ryan, N. Joyce, and W. McClelland
Poster 76
The Dawson Range batholith in Yukon and eastern Alaska forms the northwestern‐most extension of the
composite Coast Mountain Batholith. Whereas the Coast Mountain Batholith preserves largely overlapping
magmatism that spans from Jurassic to Eocene, the Middle Cretaceous plutonic rocks in Yukon are spatially
separated and/or are petrographically distinct from Jurassic, Late Cretaceous and Eocene intrusive rocks. In this
study, we integrate results of mapping, geochronology, Sm‐Nd isotopes and geochemistry to clarify the
relationships between the various phases of the Middle Cretaceous Dawson Range Batholith in the Stevenson
Ridge area. Utilizing these new and compiled data, we make inference on the sources of Middle Cretaceous
magmatism, propose a model for the generation of the Whitehorse plutonic suite, and make inferences on the
tectonic setting of the mid‐Cretaceous magmatism in the northern Cordillera.
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Zhen ZHANG University of British Columbia, British Columbia
Petrochronological Characteristics of Four Zircons from Salt Lake Crater Pyroxenite Xenoliths
Co‐authors: John Greenough and John Cottle
Poster 57
We present a comprehensive trace element and geochronology study on four zircons extracted from two
garnet‐bearing pyroxenite xenoliths recovered in Oahu, Hawaii. There are extensive published articles
discussing the origin of these xenoliths, and it has been widely accepted that these rocks were formed in the
upper mantle. Thus, our zircons provide the first non‐model ages of oceanic lithosphere mantle, and carry
critical information regarding the evolution of the convecting mantle. In situ U‐Th/Pb and trace element data
were acquired simultaneously using the laser‐ablation split‐stream method. The ages given by the zircons
scatter from 12.9 ±0.2 Ma to 80 ± 2 Ma, which is in contrast to the near‐zero age as suggested in existing
literature. Trace elements data suggest that these zircons are chemically distinct from mantle‐derived zircons
found in kimberlites, but are identical to crustal zircons. The near‐rim domains of two zircons have lower Ce/Nd
ratios compared to the core domains, indicating the zircon underwent a thermal event that was probably
resulted from the addition of a depleted component.
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