bluuebunny/crossref_metadata_2025 huggingface dataset:
An analysis of the thermal field to determine constraints on gas hydrate stability in Yukon Territory and western Northwest Territories
Authors: Smith S L
Published: March 2017

Stability conditions for the existence of gas hydrate have been analyzed for the Yukon and western Northwest Territories south of the Mackenzie Delta region. Structure I methane hydrate is stable only in the northern portion of the study area. Petrophysical
evidence suggests that gas hydrate may exist over a more extensive area. Conditions for methane-propane hydrate and methane hydrogen sulphide hydrate stability were found to exist over a large part of the region. An analysis of gas composition in the region suggests that gas hydrates composed of
heavier hydrocarbons or hydrogen sulphide may be present. Results of the analysis also indicate the possible existence of gas hydrates within 100 m of the ground surface.
Variation in earthquake ground motion on the Fraser delta from strong-motion seismograph records
Authors: Rogers G C , Cassidy J F , Weichert D
H
Published: March 2017

Strong ground-motion recordings of the magnitude (MW) = 5.3 1976 Pender Island, British Columbia and MW = 5.1 1996 Duvall, Washington earthquakes provide the best constraints, to date, on seismic site response on the Fraser delta. At low frequencies, seismic
amplification occurs on the thick soils of the Fraser delta relative to rock and firm-soil sites. The amplification is more pronounced in the horizontal component of ground motion than in the vertical. At high frequencies, modest attenuation is observed on the thick soils. The crossover from
amplification to attenuation occurs in the 5-8 Hz bandwidth. The largest ground accelerations recorded were not on the thickest sediments, but nearer the edge of the delta where the deltaic sediments and underlying Pleistocene sediments are thinner. This represents a hazard that should be taken into
account when siting buildings near the delta edge.
Nechako NATMAP Project overview, central British Columbia, year four: part 1
Authors: Struik L C , MacIntyre D G
Published: March 2017

Part one of this two-part overview summarizes 1998 bedrock and surficial mapping of the joint Geological Survey of Canada, British Columbia Geological Survey Branch, universities, and industry project. Sixteen university students assisted 25 government and
university researchers this field season. Bedrock geology was mapped in fourteen areas and surficial geology in six areas, all at a scale of 1: 50 000. Researchers studied biostratigraphy; sampled for isotopic-age dating; conducted detailed sedimentological and stratigraphic studies; measured
magnetism, gravity and density; and sampled till, silt, lodgepole pine, and rocks in various geochemical studies. New geoscience contributions include 1) extending the delineation of the Sitlika Group sedimentary and volcanic rocks southward through the Fort Fraser map area, 2) redefining large
tracts of western Cache Creek Group as Stikine and Sitlika assemblages, 3) recognition of Jura-Cretaceous contraction like the Skeena fold belt to the north, and 4) better definition of the distribution and tectonics of Miocene and Eocene volcanic and intrusive suites.
Geology of the Taltapin Lake map area, central British Columbia
Authors: Hrudey M G , Struik L C , Whalen J B
Published: March 2017

The Taltapin Lake map area (93 K/6) is characterized by Permian to Jurassic Sitlika assemblage volcanic and sedimentary rocks, the Late Triassic-Middle Jurassic Taltapin metamorphic complex of mainly amphibolite and strongly foliated to gneissic diorite, and
Jurassic diorite to granite plutons of the Stag Lake and Francois Lake suites. Tertiary Ootsa Lake and Endako groups blanket older units, and are vesicular andesites, and basalts. Ootsa Lake Group also contains dacite, rhyolite, and rhyodacite breccia. The Permo-Triassic mafic Volcanic unit, and
Triassic-Jurassic Eastern clastic unit of the Sitlika assemblage appear distinct lithologically, metamorphically, and structurally from Taltapin metamorphic complex units. The Sitlika assemblage separates rocks of Cache Creek and Stikine terranes, hence Taltapin metamorphic complex is interpreted as
a metamorphic equivalent of Stikine Terrane, rather than metamorphosed Cache Creek Terrane. The Taltapin metamorphic complex was deformed and metamorphosed prior to the Late Triassic. It was further metamorphosed and juxtaposed with Sitlika assemblage between the Late Triassic and Middle
Jurassic.
Field investigations of glacial Lake Knewstubb of the Fraser Glaciation, central British Columbia
Authors: Huscroft C , Plouffe A
Published: March 2017

Glacial Lake Knewstubb was formed during the Late Pleistocene by the impoundment of glacial meltwater in the upper Nechako River drainage basin of central British Columbia. Approximately 60 km2 of the Knewstubb Lake basin is covered with glaciolacustrine fine
sand, silt, and clay. Stratigraphic and sedimentological studies of the glaciolacustrine deposits were conducted to define the deglacial history of the area. It is inferred that the regional topography and the position of ice fronts controlled the level of the glacial lake. As the ice receded,
progressively lower outlet channels were exposed and the glacial lake level at any given time was limited by the elevation of the lowest open drainage channel.
Stratigraphic affinity of Upper Cretaceous volcanic rocks in the Churn Creek-Gang Ranch area, south-central British Columbia
Authors: Haskin M L , Mahoney J B , Enkin R J , Mustard P S , Hickson C
J
Published: March 2017

Albian volcanic rocks in south-central British Columbia may link the Intermontane and Insular superterranes. These rocks have been correlated with the Spences Bridge Group of the Intermontane Superterrane, but stratigraphically underlie Albian-Cenomanian
Silverquick conglomerate and Powell Creek Group of the Insular Superterrane. Paleomagnetic, geochemical, lithological, stratigraphic, and geochronological studies will test the Spences Bridge Group correlation. The 300-400 m thick Albian volcanic package unconformably overlies Jurassic (?)
argillite and siltstone and is unconformably overlain by Albian-Cenomanian conglomerate. Tertiary volcanic rocks and intrusions overlie or intrude the older successions. The Albian volcanic rocks are divisible into two units: a lower unit of plagioclase-phyric andesite flows, intercalated
volcaniclastic rocks and massive tuffaceous/pyroclastic flows/breccias and an upper unit of vesicular andesite, pyroclastic flows and volcanic breccias. If this package is Spences Bridge Group, its paleomagnetic inclination will place strong constraints on the Baja-British Columbia
model.
Field investigation of Cenozoic structures in the northern Cascadia forearc, southwestern British Columbia
Authors: Journeay J M , Morrison J
Published: March 2017

Structural studies of fault systems in the northern Cascadia forearc document a transition from margin-normal shortening to dextral strike-slip faulting and associated margin-parallel extension some time in the Late Oligocene-Early Miocene. The transition from
compression to extension in the northern forearc region is coeval with subduction and northeastward underplating along the Cascadia subduction zone, and with northward migration of forearc slivers and associated margin-parallel shortening in the southern Cascadia forearc of Washington State and
Oregon. We present a working hypothesis for strain partitioning along the plate margin that involves both decoupling of the northern Cascadia forearc from the subduction-accretion complex to the west and the corresponding arc to the east, and internal deformation along linked systems of dextral
strike-slip and normal dip-slip faults. The transition from compression to dextral transtension along the northern Cascadia forearc likely reflects changing boundary conditions associated with oblique subduction beneath an arcuate bend in the plate margin.
Glacial dispersal patterns and postglacial marine overlap in the Longstaff Bluff area, central Baffin Island
Authors: Dredge L A
Published: March 2017

The Quaternary geology component of the Central Baffin Project was part of a program designed to provide information for resource development. This report provides a summary of surface materials and glacial history in four areas: Longstaff Bluff, Rushmore Bay,
Astarte River, and Flint Lake. The results of this study affect the interpretation of geochemical data derived from lake sediment sampling and till sampling. Ice-flow indicators establish that materials have been transported south and west of their source areas by glaciers. Glacial materials below
an elevation of 100 m have been admixed with, or overlain by, postglacial marine sediments. Some postglacial weathering of sulphide minerals in till and bedrock has occurred. Marble-derived carbonate in till in some areas may act as a buffer to limit sulphide leaching, and may explain some
geochemical anomalies.
Proterozoic reworking in western Churchill Province, Gibson Lake-Cross Bay area, Northwest Territories (Kivalliq region, Nunavut). Part 2: regional structural geology
Authors: Hanmer S , Tella S , Sandeman H A , Ryan J J , Hadlari T , Mills A
Published: March 2017

The principal structural elements in the Gibson Lake- Cross Bay map area are, the Gibson- MacQuoid D2 homocline, overlain with possible structural discordance by a volcanic belt, intruded by Neoarchean, syn-D2 plutons; and the Cross Bay plutonic complex, wherein
S2 is deformed about south-plunging, F3 folds, associated with a coaxial L3 extension lineation, and east- northeast-trending, F4 folds. The plutonic complex is bounded to the south by the pre-, syn-, and post-D4, dextral, strike-slip Big lake shear zone. Metamorphosed, ca. 2.19 Ga, MacQuoid dykes
everywhere postdate S2, but within the Cross Bay complex and the Big lake shear zone they were deformed during D3-D4. Therefore, D3 and D4 are regional Paleoproterozoic events. Granitic plutons within the plutonic complex were intruded after D2 and before D4 fabrics, respectively, and represent
Paleoproterozoic magmatic events.
Preliminary petrography of current and potential carving stone, Gibson Lake-Cross Bay area, Northwest Territories (Kivalliq region, Nunavut)
Authors: Hanmer S , Sandeman H A , Tella S , Ryan J
J , Hadlari T , Mills A
Published: March 2017

Carving stone, used by artisans in the local hamlets of Rankin Inlet and Baker Lake, is quarried in a small-scale operation on the south side of Cross Bay, Chesterfield Inlet. This report presents a preliminary petrographic description and comparison of the
currently quarried carving stone, and of similar materials from other sites identified in the course of regional bedrock mapping during the 1998 field season in the Gibson Lake-Cross Bay area.
Review and progress report of Proterozoic granitoid rocks of the western Churchill Province, Northwest Territories (Nunavut)
Authors: Peterson T D , van Breemen O
Published: March 2017

Proterozoic granitoid rocks in the western Churchill Province comprise two age groups: a ca. 1.83 Ga group (Hudson granitoid rocks), mainly present in a region extending northeast from west of Hudson Bay to Melville Peninsula, and a ca. 1.76 Ga group (Nueltin
suite) restricted to the southwest. The older intrusions are typically equigranular, calc-alkaline, sodic granitic to granodioritic rocks with partly concordant contacts. They were approximately coeval with minette dykes of the Dubawnt Supergroup. The younger plutons are typically rapakivi granite
with chilled discordant contacts. They are enriched in LREEs, Zr, and Th, and mafic-felsic mingling textures are common. The boundary between the petrogenetic domains partly corresponds to major Proterozoic faults. The Nueltin-bearing Dubawnt domain featured subsidence and terrigenous basin
formation at 1.85-1.7 Ga.
Mineralogical investigation of sediments from a mercury-contaminated lake in northwestern Ontario
Authors: Percival J B , Drouin-Brisebois I , Lockhart W L
Published: March 2017

The form of inorganic mercury in a highly contaminated river-lake system in northwestern Ontario was investigated using routine X-ray powder diffraction analyses and scanning electron microscopy. Evidence for the occurrence of authigenic cinnabar in the peak
contaminated zone is shown. The presence of a mercuric sulphide mineral indicates anoxic conditions with depth, limits methylation of mercury in the lake sediment, and accounts for the progressive burial history of contaminated sediments.
A note on the occurrence of nepheline syenite in Calvin Township, District of Nipissing, Ontario
Authors: Currie K L
Published: March 2017

Nepheline syenite occurs about 20 km southwest of Mattawa, Ontario, as an elliptical mass about 1 km by 1.5 km in size within an east-southeast-trending belt of metagabbro and mafic gneiss. Nepheline-free syenite extends 2 km farther to the east as a belt less
than 100 m wide. The nepheline syenite is zoned from sodium-rich margins to a potassic core, but is bisected by a layer of amphibolitic gneiss similar to the surroundings. The syenite shows some mineralogical similarities to a huge massif of monzonitic rocks of granulitic affinity which lies a few
kilometres to the west. All rocks have been strongly affected by two or more periods of deformation, but the nepheline syenite shows no obvious relation to this deformation. It appears to have been emplaced as a pluton subsequent to initial deformation, but prior to final assembly of the Grenville
Province.
Calibration of a Neogene magnetostratigraphy by 40Ar-39Ar geochronology: the foreland basin strata of northern Mendoza Province, Argentina
Authors: Irigoyen M V , Villeneuve M E , Quigg F
Published: March 2017

Neogene strata exposed in the southernmost part of the Precordillera fold-and-thrust belt, Mendoza Province, Argentina, record the eastward migration of the Andean deformation front since the middle Miocene. In order to link the sequence of deformational events
occurring in the western thrust belts with the sedimentary record, the Neogene succession has been dated using magnetic polarity stratigraphy calibrated with 40Ar-39Ar isotopic dates. This paper reports on age determinations obtained by 40Ar-39Ar isotopic dating of six tuff beds interbedded in the
Neogene sequence, which assist in tying the local magnetostratigraphy to the geomagnetic polarity time scale. In addition, the age results of two samples collected from air-fall tuff horizons interbedded in Quaternary deposits, which have been dated to provide temporal constraints on the age of the
youngest Mogotes Formation and the timing of the formation of major structures in the region, are presented.
Amount of gas hydrate estimated from compressional- and shear-wave velocities at the JAPEX/JNOC/GSC Mallik 2L-38 gas hydrate research well
Authors: Lee M W , Collett T S
Published: March 2017

The amount of in situ gas hydrate concentrated in the sediment pore space at the JAPEX/JNOC/GSC Mallik 2L-38 gas hydrate research well was estimated by using compressional-wave (P-wave) and shear-wave (S-wave) downhole log measurements. A weighted equation
developed for relating the amount of gas hydrate concentrated in the pore space of unconsolidated sediments to the increase of seismic velocities was applied to the acoustic logs with porosities derived from the formation density log. A weight of 1.56 (W = 1.56) and the exponent of 1 (n = 1)
provided consistent estimates of gas hydrate concentration from the S-wave and the P-wave logs. Gas hydrate concentration is as much as 80% in the pore spaces, and the average gas hydrate concentration within the gas-hydrate-bearing section from 897 m to 1110 m (excluding zones where there is no
gas hydrate) was calculated at 39.0% when using P-wave data and 37.8% when using S-wave data.
Velocity analysis of vertical seismic profile (VSP) survey at JAPEX/JNOC/GSC Mallik 2L-38 gas hydrate research well, and related problems for estimating gas hydrate concentration
Authors: Sakai A
Published: March 2017

A VSP survey was conducted at the JAPEX/JNOC/GSC Mallik 2L-38 gas hydrate research well to determine elastic-wave velocities that were estimated by traveltime inversion of zero-offset VSP and wavefield inversion of offset VSP data. Shear-wave velocity is
estimated to be slower from VSP data than from wireline DSI measurements in the depth interval from 677 m to 889 m. The compressional-wave velocity difference between the VSP- and DSI-derived velocities are comparatively small. Synthetic seismograms from the drift-corrected DSI velocity log
correlate well with VSP sections, especially for compressional waves. Azimuthal anisotropy is suggested in VSP shear-source data and the mode of anisotropy appears to change around the base of permafrost.

By comparing computed elastic velocities with drift-corrected DSI velocity logs, two opposing gas hydrate saturation models are examined. Shear wave velocity proved to be the key data to select the correct model. The observed elastic velocity fits the computed elastic velocity for the model of gas
hydrate disseminated in pore-space with little cementation at the grain boundaries.
An assessment of coalbed methane exploration projects in Canada
Authors: Dawson F M , Marchioni D L , Anderson T C , McDougall W J
Published: March 2017

This study is a critical assessment of the coalbed methane exploration opportunities in the major coal-bearing basins in Canada. Using data from wellbores containing coal, together with experience obtained from studies in other basins, this study provides 1) a
defined set of key geological criteria necessary for succesful coalbed methane generation, retention and production; 2) a critical review of the possible geological and operational reasons for the outcome of various exploration area projects; 3) recommendations for the areas that offer the greatest
potential for economic coalbed methane accumulations.
Permafrost distribution and gound ice in surficial materials
Authors: Heginbottom J A
Published: March 2017

The Mackenzie valley lies within the permafrost region of Canada; in consequence, most moisture in the ground occurs as ground ice. Ground ice commonly forms a significant component of the upper part of the ground and has important implications for economic
development in the region. Ice occurs in many forms, most often as fillings in the intergranular pores of soils; however, it can also form much more massive bodies such as ice wedges and layers up to several metres thick. Climate warming will lead to thawing of ground ice. This will lead to surface
subsidence, increases in slope failures, and silt deposition in water bodies. Wildfire reduces the insulating capacity of ground-surface vegetation and will also induce excessive thaw. These outcomes can affect foundations and the stability of structures. Any cooling of the climate would reverse
most of these effects, and would have relatively few adverse impacts.
Shoreline permafrost along the Mackenzie River
Authors: Dyke L D
Published: March 2017

Shorelines mark one of the most abrupt changes in ground temperature in permafrost regions. The ground temperature in the vicinity of shorelines is controlled by the contrast in mean annual temperature between the particular water body and the adjacent land.
Erosion or sedimentation along shorelines complicates ground temperatures by moving the boundary between relatively cold land and warmer water. A river channel migrating due to erosion on the outside of a bend introduces the relatively warm water condition to frozen ground, causing thaw to begin. At
the same time, sediment is deposited on the opposite shore as the migration progresses. This results in ground temperatures again being determined directly by air temperature. Depending on water temperature and shoreline vegetation, temperature contrasts can range from about 4°C to over
10°C.
Stability of permafrost slopes in the Mackenzie valley
Authors: Dyke L D
Published: March 2017

Slope stability is conventionally analyzed in terms of a factor of safety', that is, the ratio between the shearing strength of a material forming a slope and the forces tending to cause sliding or failure of that material. In permafrost regions, many failures
are triggered by a decrease in strength of frozen ground due to excessive thawing and deepening of the active layer. This results in an active-layer detachment. This type of slide is often triggered by excessive thaw following the destruction of surface vegetation by fire. The most likely impact of
climate warming may be an increase in active-layer detachments if there are more fires. Although most of the deeper rotational failures occur along river banks where erosion at the foot of the slope is an important factor, long-term decreases in permafrost thickness could also contribute to
instability.
Les scientifiques des sciences de la Terre
Authors:   Department of Energy, Mines and Resources Canada
Published: March 2017

How are computer science, geology, physics and geography related? They can all lead to a career in the earth sciences. In this video, earth scientists working in five distinct disciplines (marine geology, geology, cartography, geodesy, and geophysics) relate what
attracted them to their specialty, and what a challenging and exciting life they have found as a result of their work.
Energy supply/demand trends and forecasts: implications for a sustainable energy future in Canada and the world
Authors: Hughes J D
Published: March 2017

An analysis of world and North American energy production and consumption over the past several decades indicates strong growth. Even with the growth of "zero emission" nuclear and large hydro, hydrocarbons (oil, gas and coal) made up more than 85% of world
primary energy consumption in 2002, and are forecast to make up more than 85% of a greatly expanded energy demand by 2025. Energy demand in the developing world is forecast by the Energy Information Administration to grow by 94% through 2025, when this region will account for nearly half of
the world's energy consumption. The question is, are these forecast growth rates sustainable, given the magnitude and distribution of the world's remaining energy reserves, and what are some of the political and social ramifications of maintaining this rate of consumption? Natural gas in North
America is of particular concern, as it is largely a Continental market (with the exception of about 1 % LNG at present) and demand, particularly for electricity generation, is forecast to grow dramatically over the next two decades. This presentation focuses on the "Big Picture" and how Canada
fits into it, as well as what must be considered going
forward to assure a sustainable energy future.
Beaufort-Mackenzie Basin: a review of conventional and nonconventional (gas hydrate) petroleum reserves and undiscovered resources
Authors: Osadetz K G , Morrell G R , Dixon J , Dietrich J R , Snowdon L R , Dallimore S R , Majorowicz J
A
Published: March 2017

The Beaufort-Mackenzie Basin hosts an immense petroleum resource. Fifty-two petroleum fields found by 263 wells, including four gas hydrate research wells, have discovered petroleum expected to be 172.75 x 106m3 recoverable crude oil and condensate and 254.67 x
109m3 marketable conventional natural gas. The region is estimated to have an expected undiscovered 957.2 x 106m3 recoverable crude oil and 1.64 x 1012 m3 recoverable conventional natural gas. The conventional resources are co-located with an immense gas hydrate resource estimated between 2.4 x 1012
and 87 x 1012 m3 raw natural gas in place. Development of the often co-located gas hydrate petroleum resource could augment the conventional petroleum province significantly within the production life span of the conventional onshore fields.
Overview of the coring program for the JAPEX/JNOC/GSC et al. Mallik 5L-38 gas hydrate production research well
Authors: Dallimore S R , Taylor A E , Wright J F , Nixon F M , Collett T
S , Uchida T
Published: March 2017

Forty-eight wireline coreswere taken from depths of 885 to 1151min the JAPEX/JNOC/GSCet al. Mallik 5L-38 gas hydrate production research well. Approximately 192.6 m of core were retrieved, with 90% recovery in gas-hydrate-bearing sand and conglomerate,
andmore variable recovery in gas-hydrate-free silt, organic silt, and sand below the gas hydrate stability zone at 1108 m. Cores were carefully described at the drill site within minutes of recovery to document gas hydrate character and abundance. An extensive sampling program supported
time-sensitive core studies and a wide variety of physical property, geochemical, and microbiology studies. A miniature data logger installed within each core barrel provided a continuous record of core temperature and depth during coring operations. For gas-hydrate-bearing core, a substantial
increase in the rate of core coolingwas observed upon exiting the gas hydrate stability field during transit. This additional core cooling was attributed to the endothermic dissociation of a small portion of the gas hydrate.
In situ stability of gas hydrate in reservoir sediments of the JAPEX/JNOC/GSC et al. Mallik 5L-38 gas hydrate production research well
Authors: Wright J F , Dallimore S R , Nixon F
M , Duchesne C
Published: March 2017

Laboratory experiments were conducted on four sediment samples recovered from the JAPEX/JNOC/GSC et al. Mallik 5L-38 gas hydrate production research well, to characterize the in situ stability of gas hydrate at various locations within the Mallik reservoir.
Measured sample salinities ranged from less than 10 to about 50 ppt (parts per thousand). Methane hydrate was formed within each of the test
specimens using a specially designed reactor cell having a small headspace volume. Each specimen was stabilized at a pressure-temperature condition corresponding to the depth of sample recovery, and was subsequently warmed to force dissociation of its gas hydrate content. Pressure-temperature (P-T)
conditions were continuously recorded during the dissociation stage of the experiments. Results indicate that the partition between gas hydrate stability and instability should be considered as a P-T phase-boundary envelope rather than a discrete threshold, and that the gas hydrate saturations
achieved in the laboratory were constrained by the salinity of the sediment pore waters.
Geochemistry of the interstitial waters of the JAPEX/JNOC/GSC et al. Mallik 5L-38 gas hydrate production research well
Authors: Matsumoto R , Tomaru H , Chen Y F , Lu H , Clark I
D
Published: March 2017

Interstitial waters were extracted from the sediments of the JAPEX/JNOC/GSC et al. Mallik 5L-38 gas hydrate production research well drilled in the Mackenzie Delta, and analyzed for Cl- , SO4 2- , Na+, K+, Ca2+, Mg2+, Sr2+, and Ba2+. Cored intervals are divided
into zone 1 (low salinity), zone 2 (higher salinity), zone 3 (low salinity), and zone 4 (high salinity), in descending order. Zones 1 and 3 correspond to
gas-hydrate-bearing sandstone, whereas zone 2 is a gas-hydrate-freemudstone and zone 4 a gas-hydrate-free sandstone below the base of gas hydrate stability. Anomalies of low Cl- and Na+ concentrations indicate that gas hydrate saturations (Sh) are 60 to 85%, which is not always consistent with
Sh values obtained from logging data. This is because of a build-up of either saline or fresher residual water during the formation/dissociation of gas hydrate in a closed system. An unusually higher concentration of SO4 2- in organic-rich, deep-seated sediments suggests a likely invasion of
seawater and contamination by drilling fluids.
Evidence of minimal methanogenic numbers and activity in sediments collected from the JAPEX/JNOC/GSC et al. Mallik 5L-38 gas hydrate research well
Authors: Colwell F S , Nunoura T , Delwiche M E , Boyd S , Bolton R , Reed D W , Takai K , Lehman R M , Horikoshi K , Elias D A , Phelps T
J
Published: March 2017

Twenty-three cores from JAPEX/JNOC/GSC et al. Mallik 5L-38 gas hydrate research well were characterized to determine if methanogens were present. Archaeal 16S rDNA could be detected in only six of the samples resulting in eight sequences with relationship to the
Miscellaneous Crenarchaeotic Group (seven clones) and the Subsurface Euryarchaeotic Group (one clone). The single Euryarchaeota sequence appeared to be unrelated to methanogens. Subsamples from the same cores yielded variable results upon DNA extraction and amplification. Although methanogenic
CoenzymeM(CoM) was detected in 13 of the 20 cores tested, methanogenic methyl CoM reductase (mcr) genes were not amplified from the samples when using a sensitive quantitative polymerase chain reaction technique. No methane was generated
in cultures amended with radiolabelled substrates. Variable detection of archaeal DNA suggests that it exists in low quantities or that microbial presence in the sediments is dictated on a small scale. Overall, the data suggest exceedingly low methanogen numbers and activities in these deep
sediments.
Characterization of JAPEX/JNOC/GSC et al. Mallik 5L-38 core samples in the environmental scanning electron microscope
Authors: McGrail B P , Young J S , Martin P F , Alexander M L
Published: March 2017

Core samples from the JAPEX/JNOC/GSC et al.Mallik 5L-38 well were studied undermethane and nitrogen gas atmospheres in an environmental scanning electron microscope equipped with a cryostage, video recorder, and mass spectrometer. Gas hydrate and water-ice
formation and dissociation were imaged while simultaneously collecting gas samples for analysis. Gas hydrate crystals appeared to grow epitaxially under a methane atmosphere in the environmental scanning electron microscope, whereas only loosely agglomerated water-ice crystallites were observed
under an N2 gas atmosphere. The peak rate of gas hydrate dissociation in Mallik sediment samples occurred at 217 ± 2K; however, the peak rate was at 236 K for an artificial methane hydrate sample synthesized from crushed ice.
Waveform tomography images of velocity and inelastic attenuation from the Mallik 2002 crosshole seismic surveys
Authors: Pratt R G , Hou F , Bauer K , Weber M
Published: March 2017

Time-lapse crosshole seismic data were acquired at the Mallik field, Northwest Territories (Canada) as a part of the 2002 Mallik GasHydrate Production Research Well Program.Waveform tomography was used to form high-resolution quantitative images of the seismic
velocity and attenuation from the first repeat survey, using frequencies between 100 Hz and 1000 Hz. A preprocessing flow was applied to the waveform data that includes tube-wave suppression, low-pass filtering, spatial subsampling, time-windowing, and amplitude equalization. The starting model for
the waveform tomography was obtained from picked traveltimes by anisotropic velocity tomography. The gas-hydrate-bearing sediments are imaged as laterally continuous, high-velocity anomalies; they also are characterized by an apparent increase in attenuation. Individual layers as thin as a few
metres are resolved on the velocity images, and can be followed across the target region. The images reveal subtle lateral changes in velocity and in the attenuation factor.
Well-test analysis for gas hydrate reservoirs: examination of parameters suggested by conventional
analysis for the JAPEX/JNOC/GSC et al. Mallik 5L-38 gas hydrate production research well
Authors: Kurihara M , Funatsu K , Kusaka K , Yasuda M , Dallimore S
R , Collett T S , Hancock S
H
Published: March 2017

In the Mallik 2002 Gas Hydrate Production Research Well Program, formation tests with a Modular Formation Dynamics Tester (MDT)TM tool were conducted and the test results were analyzed using conventional pressure-transient test-analysis methods. The reliability
of the reservoir-parameter estimates, however, is uncertain because of the abrupt change in gas hydrate saturation associated with gas
hydrate dissociation during the tests.

To investigate the applicability of these methods, the bottomhole-pressure responses during MDT tests in the hypothetical and actual gas hydrate zones were predicted using a numerical simulator and then analyzed by conventional test-analysis methods. This study revealed that the conventional methods
might indicate the average effective permeability over the area of gas hydrate dissociation, and that they might accurately suggest the radius of gas hydrate dissociation only when applying appropriate multiphase-fluid properties and production rates to the cases with high gas hydrate
saturation.
Numerical study of constant-rate gas production from in situ gas hydrate by depressurization
Authors: Hong H , Pooladi-Darvish M
Published: March 2017

This paper presents a numerical model for studying the potential of the depressurization method for gas recovery from gas hydrate reservoirs with an underlying free gas zone. The model includes the equations for gas-water multiphase flow, conductive and
convective heat transfer, and intrinsic kinetics of endothermic gas hydrate decomposition.

The results indicated that a considerable amount of gas can be generated and produced by the depressurization method. For the cases studied, half of the gas production rate of 5 x 104 standard (std) m3/day (roughly 1.8 million standard cubic feet per day (MMSCF/day)) is from gas hydrate
decomposition. Mechanistic and sensitivity studies were performed that suggested that the rate of heat transfer plays an important role in the process. The simulation results suggested that if the reaction-rate constants are sufficiently small, the overall rate of gas generation could be affected.
There is therefore need for determination of thermal conductivity and kinetic constants for gas hydrate in porous media.
Metal distribution in peat hummocks and hollows within 100 km of the copper smelter, Rouyn-Noranda, Quebec
Authors: Kettles I M
Published: March 2017

Profile samples were collected from peat hummocks and hollows from 37 peatlands within a 100 km radius of the Horne copper smelter, to investigate the value of peat as an historical record of smelter metal emissions. Splits of 630 samples were digested with
HNO3-HClO4 prior to analysis for smelterrelated (Cu, Pb, Zn) and non-smelter (Ni) elements. Twenty-four samples were subjected to a four-step sequential extraction analysis to identify the main metal residence sites. Peat age was constrained from 137Cs, bulk density, and vertical growth rate data.
Concentrations of Cu, Pb, and Zn were relatively low in the uppermost 20 cm of the hummocks and increased markedly between depths of 20 and 45 cm. In the tallest hummocks, metal concentrations decreased again below 50 cm depths and, by 60 to 75 cm depth, reached values less than those in the
uppermost 20 cm. This pattern was most pronounced within 25 km of the smelter but was still discernible in hummocks at distances of more than 60 km. A similar pattern of increased and decreased concentrations was found in hollows, but it was compressed over the uppermost 20 cm of the hollow peat
sequence. In hummocks 10 km and more from the smelter, about 25% of the Cu and 75% of the Pb and Zn resided in the labile phases, whereas closest to the smelter, in the 7 km hummock, even larger amounts of these elements were labile. In contrast to the smelter-derived elements, Ni
concentration in hummocks and hollows varied.
Digital elevation model and shaded relief map
Authors:   Geomatics Canada
Published: March 2017

The Canadian Digital Elevation Data, Level 1 (CDED1) consists of an ordered array of ground elevations at regularly spaced intervals. The CDED1 is based on National Topographic Data Base (NTDB) digital files at scales of 1:50 000 and 1:250 000 or various scaled
positional data acquired from the provinces, according to the National Topographic System (NTS).
The coverage for every file corresponds to half an NTS map, which means that there are western and eastern parts to the CDED1 for each NTS map. The grid spacing is based on geographic coordinates at a maximum and minimum resolution of 0.75 and 3 arc seconds for the 1:50 000, and 3 and 12 arc seconds
for the 1:250 000 respectively, depending on latitude. A CDED1 file consists of elevation data recorded in metres relative to Mean Sea Level (MSL) based on the North American Datum 1983 (NAD83) horizontal reference datum. The Centre for Topographic Information (CTI) jointly produces the CDED1 with
federal and provincial government agencies and the private sector, using terrain-modelling software.
CDED1 files are delivered in ASCII format for either DOS or UNIX operating systems and are available via the File Transfer Protocol (FTP). The data should be compatible with all translators designed for the United States Geological Survey (USGS) Digital Terrain Elevation Data (DTED). The files are
compressed using the PKZIP compression software.
The shaded relief image is created from the The Canadian Digital Elevation Data, Level 1 (CDED1) which consists of an ordered array of ground elevations at regularly spaced intervals. The CDED1 is based on National Topographic Data Base (NTDB) digital files at scales of 1:50 000 and 1:250 000 or
various scaled positional data acquired from the provinces, according to the National Topographic System (NTS). The shaded relief image gives a simulated appearance of the sun shining on the terrane at a specific azimuth and altitude.
Geochemical investigations of high-grade quartz-scheelite veins of the Cantung Mine, Northwest Territories
Authors: Yuvan J , Shelton K , Falck H
Published: March 2017

High-grade quartz-scheelite veins (up to 3.7 wt.% WO3) in the open pit orebody of the Cantung mine, Tungsten, Northwest Territories occur 300 m vertically above a Cambrian limestone-Cretaceous monzogranite contact along which the E-Zone, a world-class
tungsten skarn orebody, is developed. The trend of an 80 m wide vein swarm is roughly parallel to the strike and dip of a near-vertical aplite dyke along the edge of the open pit. Adjacent to these quartz-scheelite veins, dark green alteration selvedges overprint earlier light green skarn
alteration. This overprint implies that the high-grade quartz-scheelite veins are not part of the early skarn-forming event but represent a distinct, later event.

Oxygen isotope data from vein-hosted quartz-scheelite pairs yield equilibrium depositional temperatures of 430 to 595°C. These temperatures indicate that the high-grade quartz-scheelite veins are related to a deep magmatic hydrothermal system and are likely a distal expression of a protracted
skarn-forming event, perhaps related to aplite dyke emplacement. Quartz-scheelite veins did not form in a shallower, cooler, hydrothermal system during uplift.

Primary ore fluids in quartz-scheelite veins from the open pit orebody, in skarn-related quartz veins from the E-Zone orebody, and in aplite dykes are grossly similar H2O-CO2-NaCl ± CH4 fluids. However, two distinct end-member fluids have been documented: aplite-related fluids and skarn-related
fluids (in quartz veins from the E-Zone orebody). Fluids in high-grade quartz-scheelite veins contain components of both end-member fluids. High-grade quartz-scheelite veins from the open pit orebody share a common structural attitude with aplite dykes. Fluids in veins from the open pit orebody
contain an aplite-related fluid end-member even when occurring up to 70 m from the nearest exposed aplite dyke. Thus, quartz-scheelite veins and aplite dykes in the open pit orebody probably have a genetic relationship in addition to their structural relationship.

The authors envision a conceptual model for the Cantung hydrothermal system in which ore-grade tungsten deposits formed where fluids emerged from the granite and encountered rocks favourable for skarn development (e.g. cleaner 'ore limestone' versus cherty 'swiss cheese limestone'). Due to the
folded geometry of the sedimentary sequence, in other areas along the granite contact, the fluids emerging from the granite encountered strata less favourable to skarn development (i.e. argillite). Where these less favourable units were breached by fracture systems, potential skarn-forming fluids
(and aplite dykes) gained access to host rocks more conducive to ore development vertically distal to the granite contact. The presence of magmatic ore fluids distal to intrusions is intriguing and has significant implications for mineral resource assessment in the region.
Appendix 3: Spring geochemistry: a tool for mineral exploration in the South Nahanni River Basin, NWT
Authors: Caron M -E
Published: March 2017

Geochemical data from over 200 springs within the remote 37,000 km2 South Nahanni River Basin of the Mackenzie Mountains, Northwest Territories, were used to evaluate the economic mineral potential of the region which is proposed for a national park designation.
Trace element analyses were evaluated using three different approaches (the sum of trace element concentrations as a percentage of total dissolved solids, identifying individual elevated trace elements, and the inverse use of the Ficklin Diagram). Two out of the three approaches detected the two
known deposits of the area, Prairie Creek and Tungsten, but not with the same method in each case, indicating that a multi-pronged approach is best. The springs are elevated in trace elements in comparison to mineral deposit related waters around the world. Silica geothermometry determined the
average depth of circulation of the springs to be 2.1 km in the warm or hot springs and ranging from 4.7 km to less than 200 m for the entire dataset, indicative of the accessibility of the predicted mineralized zones. These simple statistical and graphing methods can identify mineralized zones
quickly and efficiently in a largely under-explored area.
Digital geoscience atlas of Baffin Island (south of 70°N and east of 80°W), Nunavut
Authors: St-Onge M R , Ford A , Henderson I
Published: March 2017

This Open File contains: (1) a geological bedrock compilation (1:500 000 scale); (2) planar and linear structural point data; (3) scanned images of source maps utilized for the bedrock compilation; (4) sample number, radiometric age, interpretation, dated
material, and analytical method for available geochronology data; (5) a compilation of geochemical data for volcanic and granitoid units; (6) a compilation of mineral occurrences detected through ground observations, geochemical analyses of rock samples for target elements, or geophysical surveys;
(7) aeromagnetic (total field and 1st derivative) and gravity compilations; (8) 3-D models and radiometric data; (9) available surficial material compilations (1:100 000 and 1:250 000 scales); (10) hydrographic features and topographic contours (1:250 000 scale); (11) a digital elevation model and
shaded relief map; and (12) a Landsat image for Baffin Island and adjacent islands (Nunavut) south of 70°N and east of 80°W. The purpose of this Open File is to provide a complete, digital, internally consistent, and geo-referenced collection of spatial data that can be cross-referenced
and will assist interested parties in mineral exploration, environmental studies, land-use planning, and other investigations requiring up-to-date Earth Sciences information and data.
Aux limites du possible
Authors:   Department of Energy, Mines and Resources Canada
Published: March 2017

This video is a documentary about high Arctic exploration through an overview of drilling techniques adapted for Arctic weather.
A new world below
Authors:   Department of Energy, Mines and Resources Canada
Published: March 2017

This video focuses on marine research and exploration of the ocean floor off Canada's Atlantic coast, a vast area of some 2 500 000 square kilometers.
200 years of geoscience in Canada
Authors:   Natural Resources Canada
Published: March 2017

This video is a photo and video montage of 200 years of geoscience in Canada.
Structural evolution of Tertiary rocks on Judge Daly Promontory
Authors: Saalmann K , Tessensohn F , von Gosen W , Piepjohn K
Published: March 2017

Tertiary deposits on Judge Daly Promontory allow for the study of unequivocal Eurekan structures. As a result of their position adjacent to Nares Strait, the structural evolution of the Tertiary strata provides insight into the kinematics of the proposed Wegener
Fault and Greenland plate, assumed to be situated offshore in the strait.
The geometry of the deformation, as well as the analysis of faults and shear planes, suggests a twostage structural evolution of convergent tectonics on Judge Daly Promontory during the Tertiary. The pattern of steeply dipping fault planes on the promontory as well as in Tertiary rocks indicates an
episode of sinistral strike-slip tectonics in the late Paleocene to Early Eocene. This phase was followed by northwest - southeast contraction (Early to Middle Eocene) resulting in renewed or continued activation of the pre-existing faults, and southeast-directed thrusting combined with left-lateral
shear. The structural evolution during the Tertiary can be linked with plate-tectonic models for the Canadian Arctic region.
Thermal conductivity, thermal diffusivity, density and porosity of crystalline rocks
Authors: Drury M J
Published: March 2017

Tables of thermal conductivity, thermal diffusivity, density and porosity are presented for several groups of crystalline rocks, measured by the Geothermics Group of the Earth Physics Branch during its existence from 1962 to 1986. Mean and standard deviations are
also given for each major rock type. Mean conductivity ranges from 1.96 W/mK for basalt to 3.50 W/mK for granite. Mean diffusivity ranges from 0.69 mm2/s for basalt to 1.34 mm2/s for granite.
Norman wells pipeline monitoring sites, ground temperature data file: 1984-1985
Authors: Burgess M M
Published: March 2017

The Geological Survey of Canada has maintained a network of permafrost thermal monitoring sites along the Norman Wells pipeline corridor between Norman Wells (NWT) and Zama, Alberta, since 1984. A total of 23 thermal fences or instrumented cross-sections have
been established at which ground temperatures are measured both on and off the pipeline right-of-way (ROW). The design of the thermal fence ... allows an investigation of the effect of ROW clearing, pipeline trenching, installation and operation on the ground temperature and also to compare the
thermal regime of the ROW and the surrounding terrain. Temperatures are measured to depths of 5 m close to the pipe and at a depth of 20 m between 4 and 10 m from the pipe and off-ROW. Initial manual data collection was at monthly to bi-monthly intervals decreasing to one to three times annually in
later years. In the mid 1990s, a number of temperature cables were connected to dataloggers to provide high frequency measurements.
TEM survey to map the distribution of permafrost, seismic line 86026, Tuktoyaktuk, N.W.T.
Authors:   Geo-Physi-Con Co. Ltd.
Published: March 2017

ln a jointly supported project for Energy, Mines and Resources and Home Oil, Geo-Ph ysi-Con conducted a transient electromagnetic sounding survey along a 11 km line south of Tuktoyaktuk, N.W.T. The project was conducted to test the use of electromagnetic methods
in developing static corrections for seismic surveys. Electromagnetic results reported here propose a two-layer mode! for permafrost 300 to 500 m thick , The mode! shows good agreement with down-hole electrical logs.
Preliminary results from shallow drilling in the Anahim Volcanic Belt, B.C.
Authors: Bentkowski W H , Lewis T J
Published: March 2017

The Anahim Volcanic Belt is a late Cenozoic succession of volcanic rocks considered to be a zone of potential geothermal energy sources. Sixteen shallow holes were drilled near the eastern end of the volcanic belt to determine if there is a crustal thermal
anomaly associated with the volcanic belt.
Five holes drilled in the rugged topography of the Omineca Crystalline Belt north of Blue River are significantly affected by water flow and average geothermal gradients cannot be determined. However the remaining eleven holes near 100 Mile House in the relatively subdued topography of the
Intermontane Belt show consistent gradients largely unaffected by water flows below 30 m. The gradients range from 21 .5 to 30.5 mKm-1, depending on the type of rock penetrated, which ranges from quartz monzonite to diorite. Heat generation values average 0.90 m-3. Heat flux estimates of 60 to 65
mWm-2, similar to values obtained in the southern Intermontane Belt, suggest that no significant crustal heating has occurred.