bluuebunny/crossref_metadata_2025 huggingface dataset:
Preliminary diatom analysis of selected samples from Lake Abitibi and Glacial Lake Ojibway, Ontario and Quebec
Authors: Prévost C L , Veillette J J , Hamilton P
B
Published: March 2017

In August 1993, fourteen long cores were collected from various parts of Lake Abitibi in order to identify and date the transition periods between Glacial Lake Ojibway, ancestral Lake Abitibi, and modern Lake Abitibi. Ongoing geochemical, pedological, and
paleoecological studies are conducted to find traces of extreme lake-level fluctuations and dry lake bed conditions in postglacial time. Diatom (algae) analysis is one paleoecological method used. Preliminary results from 8 samples of Lake Ojibway varved clay and Cochrane till reveal that the diatom
flora of Glacial Lake Ojibway was poor, since only 15 diatom species from 8 genera were identified. This low number is likely the result of several factors (turbidity, high rates of sedimentation, lack of nutrients, icebergs) that created poor growing conditions in the cold paleowaters and hampered
the successful development of diatom communities. The diatom flora of Lake Abitibi is much more developed: 149 species from 39 genera were identified in modern surficial material from the top of 14 cores. This preliminary study indicates that diatom analyses can successfully be used to help
characterize the sedimentary transition from Glacial Lake Ojibway to Lake Abitibi.
The spectacular cross-striated outcrops of James Bay, Quebec
Authors: Veillette J J , Roy M
Published: March 2017

Bedrock on the east coast and on some James Bay islands shows spectacular examples of cross-striations that reveal a shift from initial northwestward ice flow, followed by westward, southwestward, and local southeastward and southwestward flows related to the
opening of James Bay during deglaciation of the region. The high quality of striated outcrops is attributed to their freshness, which results from a combination of postglacial uplift, the protective effect of glacial deposits, and recent erosion of these deposits by wave action. Photographs and
schematic illustrations are used to explain the processes at work in this particular marine environment.
Contour map of the sub-Quaternary bedrock surface, Strait of Georgia and Fraser Lowland
Authors: Hamilton T S , Ricketts B D
Published: March 2017

The sub-Quaternary bedrock surface beneath the Strait of Georgia and Fraser Lowland is depicted on a contour map. For the Strait of Georgia area, map construction is based on marine seismic surveys, whereas for the Fraser Lowland, the map is based on outcrop and
limited data from boreholes. The morphology of the bedrock surface reflects two processes: probable Neogene tectonic subsidence, and Pleistocene glacial erosion. Unconsolidated Pleistocene sediments are 300-500 m thick beneath much of the Fraser delta and the Strait of Georgia, and up to 700 m
thick in parts of the Fraser Valley.
Earthquakes in the Vancouver area
Authors: Rogers G C
Published: March 2017

Vancouver and the densely populated Lower Mainland region of southwest British Columbia are situated over an active subduction zone. The dynamic geological setting makes this region subject to frequent seismic activity and contributes to a higher risk of large
damaging earthquakes than in other parts of Canada. Earthquakes that may present a hazard to the area are located in three distinct source regions: earthquakes within the continental crust, deeper earthquakes within the subducted oceanic plate, and earthquakes on the subduction boundary between the
lithospheric plates. While Vancouver (incorporated 1886) has not experienced a damaging earthquake in its short history, large earthquakes nearby have been strongly felt and there is paleoseismic evidence for very strong shaking in prehistoric time. Most of the region is placed in Seismic Zone 4
in the 1990 edition of the National Building Code of Canada. Ongoing microearthquake activity and felt earthquakes occurring in most years are reminders of the seismic hazard.
The role of granites in the evolution of the Folly Lake diorite, Cobequid Highlands, Nova Scotia
Authors: Koukouvelas I , Pe-Piper G
Published: March 2017

The Folly Lake diorite is an earliest Carboniferous pluton in the Avalon terrane of northern Nova Scotia. It is bounded to the south by a major strike-slip fault zone, the Rockland Brook fault. Structural and petrological observations show that minor granite
phases in the pluton decrease northwards from the fault and record a complex history of deformation. Strong mylonitic foliation in granite dykes hosted in undeformed diorite near the Rockland Brook fault indicate that granitic magma lubricated the deformation of the fault zone and the diorite
pluton. The Rockland Brook fault is a positive flower structure similar to the Cobequid fault zone.
Halokinetic controls on the sedimentary architecture of the Inverness Formation, western Cape Breton Island, Nova Scotia
Authors: Brown J P
Published: March 2017

Braided fluvial sand bodies of the Inverness Formation consist of multiple stacked sand units (10-15 m thick) which combine to produce unusually thick sand bodies up to 200 m thick. Paleocurrent data from the fluvial sand bodies indicate frequent and radical
changes of the sediment transport direction. The paleocurrent orientation shows changes of up to 180° between vertically adjacent sand units and has a range in excess of 90° within a single sand unit. Re-analysis of the Mabou 1978 Geophysical Survey, using seismic sequence stratigraphic
and seismic facies analysis techniques, has revealed the presence of three salt diapirs originating from the Windsor Group. Progradational seismic sedimentological facies and incised, onlap, offlap and truncated seismic reflectors are used to reconstruct the sedimentary architecture of the Inverness
Formation. It is evident from the spatial and temporal distribution of the salt diapirs and seismic facies that halokinesis had a dramatic effect upon the sedimentary architecture of the Inverness Formation.
A preliminary microthermometric study of the Sugar Camp, Yankee Line, and MacPhails Brook Pb-Zn showings, Cape Breton Island, Nova Scotia
Authors: Chi G , Savard M M
Published: March 2017

A number of small Pb-Zn occurrences are hosted by Carboniferous basal Windsor carbonates in addition to the Jubilee deposit on Cape Breton Island in Nova Scotia. This paper reports some preliminary microthermometric data on the Sugar Camp, Yankee Line, and
MacPhails Brook showings, and compares them with data from the Jubilee and Gays River deposits. Fluid inclusions from all the showings have first-melting temperatures lower than -55°C, indicating that the fluid composition may be modelled by the system H2O-NaCl-CaCl2. Bulk salinities are
generally between 20 and 30 wt% NaCl equivalent, comparable to the Gays River deposit but statistically higher than the Jubilee deposit. Homogenization temperatures vary between 123-220°C, 79-110°C, and 66-118°C for the Sugar Camp, Yankee Line, and MacPhails Brook showings,
respectively. The microthermometric attributes of the Sugar Camp showing have more affinities with those of the Gays River deposit than those of the Jubilee deposit.
Improving measurement accuracy of formation resistivity factor measurements for tight shales from the Scotian Shelf
Authors: Katsube T J , Scromeda N , Williamson M
Published: March 2017

Methods for improving measurement accuracy of formation resistivity factor (F) has been studied for nine shale samples from the Venture Gas Field, offshore Nova Scotia. F is one of the petrophysical parameters that provides information on shale seal quality for
hydrocarbon exploration. It is determined by measuring electrical resistivity (prn) for samples saturated with NaCl solutions with different resistivities (pw) and inserting the values into the Patnode and Wyllie Equation: 1/prn = 1/(Fpw) + 1/pc, where pc is the pore surface resistivity. According
to this equation, the relationship between 1/pr and 1/pw should be linear. Cases where deviation from linearity occur cause concern over measurement accuracy. A previous study suggested that the problem is eliminated by using NaCl solutions with high concentrations and long saturation times.
Adopting this method solves the problem for six of the nine samples. The remaining three coincide with those that have minor amounts of kaolinite.
The Plage-Charron, Quebec, landslide of August 5, 1994
Authors: Aylsworth J M , Lawrence D E , Traynor J A
Published: March 2017

On August 5, 1994, a landslide involving approximately 5000 m3 of Leda clay occurred along the Ottawa River at Plage-Charron, south of Eardley, Quebec. The failure followed an extreme precipitation event in a year when precipitation was well above normal values.
It is the most recent in a series of relatively small landslides that occur at a frequency of about one per year along an arcuate, 1.6 km long bluff in Champlain Sea clays. The landslide is described, a history of regular slope failure along the bluff is documented, and factors of safety are
estimated for the slope.
Radiolarian biostratigraphy and implications, Cache Creek Group of Fort Fraser and Prince George map areas, central British Columbia
Authors: Cordey F , Struik L C
Published: March 2017

As part of the new Nechako NATMAP project, radiolarian investigations from the Fort Fraser (93K) and Prince George (93G) map areas in central British Columbia provide control on the age and structures of the Cache Creek Group and related units. Twenty-five
localities of radiolarian chert, siliceous mudstone, limestone, and chert-bearing conglomerate from the Cache Creek Group and the Sifton Formation range in age from late Pennsylvanian-early Permian to Early Jurassic (Pliensbachian). These results provide a new stratigraphic framework for the area.
In central British Columbia, Cache Creek Group upper Paleozoic rocks include limestone, chert, and basalt, and may include gabbro and ultramafics, and Mesozoic rocks include greywacke, siltstone, argillite, limestone, and basalt tuff. Regionally, these results give new information for correlations
within the Cache Creek Terrane as a whole, for instance about transitional intervals of sedimentation from carbonate to chert and chert to hemipelagics.
Electrical resisitivity of rock samples from Vancouver Island, British Columbia
Authors: Scromeda N , Katsube T J , Best M
Published: March 2017

Bulk electrical resistivity (rho-r) has been measured on 16 rock samples (volcanic, plutonic, and sedimentary) from northern Vancouver Island to assist in the interpretation of ground electromagnetic surveys. Effective porosity (phi-E) and bulk density (delta-B)
have also been measured to provide additional information on the rocks.

Results indicate that rho-r values of these rocks are generally outside the reported range for similar rocks. The rho-r values for the sandstones (110-6700 ohm-m) resemble Precambrian terrestrial sandstones (300-5000 ohm-m). The larger rho-r values for the volcanic rocks (230-26 000 ohm-m) are
considerably larger than the generally accepted values (10-5000 ohm-m). The rho-r values (230-290 ohm-m) for the diorites have little resemblance to those of crystalline rocks (47 000-280 000 ohm-m). These results, including the phi-E and delta-B data, suggest that some of these rocks are extremely
tight with the majority of the pores being blocked, and that the diorites are unusually porous.
An overiew of xenolith-bearing Neogene to Recent volcanics in the northern Cordillera
Authors: Hamilton T S , Dostal J , Shaw J M
Published: March 2017

During August 1994 and July 1995 xenoliths were collected from 19 Neogene to Recent volcanic centres in the northern Cordillera including: Prindle (Alaska); 60 Mile, Clinton Creek, 40 Mile, Ne Che Dhawa, Alligator Lake (Yukon); Ruby Mountain, Cracker Creek,
Volcano Creek, Chikoida Mountain, Llangorse, Ash Mountain, 3 Caribou Tuya, South Tuya, Matthews Tuya, Castle Rock, Maitland Creek, Aiyansh/Tseax River, and Summit Lake (British Columbia). This report presents the locations, xenolith types, and preliminary descriptions. Xenoliths types include:
depleted and undepleted spinel lherzolite, clinopyroxene megacrysts, clinopyroxenite, gabbro, and granitic and metamorphic rocks (including granulite facies banded gneiss). Microprobe analyses for olivine, orthopyroxene, and clinopyroxene from peridotite xenoliths in three of the centres are
consistent with a mantle paragenesis.

The xenoliths are the foundation for ongoing petrological studies of the Cordilleran crust and upper mantle. They represent the only physical samples of the northern Cordilleran subsurface geology available to constrain the geophysics from the Lithoprobe SNORCLE transects.
A progress report on Mississippi Valley-type deposits of the Mackenzie Platform: fluid inclusion studies in sphalerite, quartz and dolomite from the Bear deposit, Northwest Territories
Authors: Carrière J J , Sangster D F
Published: March 2017

Fluid inclusion, petrographic, cathodoluminescence, and microprobe studies were conducted on gangue and sulphide minerals. Primary inclusions in dolomite contain a fluid representative of the original hot, moderately high saline brine (20.7 to 25 equivalent
wt.% NaCl, 210°C average homogenization temperature (Th)). In sphalerite, fluid trapped in pseudosecondary inclusions is probably a sample of the mineralizing fluid (14.2 to 19.4 equivalent wt.% NaCl, average Th 188°C), which was diluted and/or reset by later tectonic events.
Temperatures of the first recognized liquid + ice + vapour in fluid inclusions range from -35° to -52°C, indicating the presence of salt(s) other than NaCl. The presence of CO2 is confirmed in single phase inclusions in quartz and dolomite, and the presence of CH4 is suggested through
indirect evidence in the single phase inclusions. Cathodoluminescence revealed three textural varieties of dolomite. Microprobe analyses identified dolomite and calcite, and characterized the cathodoluminescence zonation in the saddle dolomite.
Paleoenvironmental significance of biota of the Ostracode zone (Mannville Group) in south-central Alberta
Authors: Banerjee I , Raychaudhuri I
Published: March 2017

The Ostracode zone (Late Aptian-Early Albian) is an informally designated lithostratigraphic unit that is a key stratigraphic interval within the Lower Cretaceous Mannville Group due to its regional extent, unique limestone-bearing lithology and inferred marine
origin. The purpose of this subsurface study is two-fold: first, to present new data on trace fossils of this unit; and second, to review the paleoenvironmental significance of the entire fossil assemblage reported from this unit including macrofossils, microfossils and trace fossils.

Nineteen ichnogenera have been identified in this study. The softground ichnofossil assemblages are consistent with the Cruziana ichnofacies. Marginal marine environments are indicated by the small size of individual traces, overall low-abundance/moderate-diversity assemblages, and ichnofossil
suites dominated by two to three genera with simple forms. Firmground and hardground examples of the Glossifungites and Trypanites ichnofacies, respectively, are also recognized.

A review of previous studies on the body fossils within the Ostracode zone (bivalves, ostracodes, foraminifera and dinoflagellates) corroborates a marginal marine interpretation. A very shallow, restricted inland seaway with fluctuating salinity, stagnant bottom conditions and repeated episodes of
emergence, is indicated by the sedimentological and paleontological data.
Electrical characteristics of rock samples from the La Ronge Domain of the Trans-Hudson Orogen, northern Saskatchewan
Authors: Katsube T J , Jones A G , Scromeda N , Schwann P
Published: March 2017

Electrical resistivities of rock samples (gneiss, greywacke and argillite), obtained from the western part of the La Ronge Domain, were studied to determine the source of elevated electrical conductivities observed deep in the subsurface of the region.

Analyses show that the resistivities of these rocks cover a wide range of values (0.3-2x104 Ohm-m). While the larger values are typical for these types of rocks, the smaller ones are likely due to layers (thicknesses of about 1-5 mm) of sulphide concentrations. These layers are also a source of
significant electrical resistivity anisotropy. These rocks are folded, with sulphide layers accumulated near the hinge of the fold forming a source of high electrical conductivity along its axis. Generally, the resistivities are 3-8 Ohm-m in the direction of the fold axis, and 2000-20 000 Ohm-m for
samples from the host gneissic rock, which gives a bulk anisotropy of 200:1 to 7000:1 for the metasedimentary unit.
Corals of the Advance Formation (upper Middle Ordovician), northern Rocky Mountains of British Columbia
Authors: Elias R J
Published: March 2017

All corals known from slope deposits of the Advance Formation are solitary rugosans. Paliphyllum norfordi n. sp., represented by a single specimen, and Grewingkia burdenensis n. sp., which is more common, are the only identifiable species. Diversity and abundance
are low compared with the taxonomically different coral fauna in approximately coeval shelf deposits of the Johnson Spring Formation, California. Grewingkia burdenensis is considered to be the ancestor of Grewingkia robusta, a Late Ordovician species that was widely distributed within the Red
RiverþStony Mountain Province of cratonic North America. Paliphyllum norfordi is the earliest paliphyllid worldwide, and the only rugosan with dissepiments known from the Middle Ordovician of North America. It appears to be most similar to some representatives of Paliphyllum in the Dolbor Formation
(uppermost Caradocþlowermost Ashgill), Siberian Platform. Coralla of G. burdenensis were subject to little current action or transportation. This species generally lived freely on soft substrates; sediment cohesion may have been low. In one stratigraphic interval, the presence of specimens with
attachment structures suggests that the substrate may have been unfavourable for the coral's normal mode of life, or that more objects suitable for attachment were available than usual. The corallum of P. norfordi was subject to higher current energy and possibly transportation, and/or longer
exposure before final burial. This coral was overturned, possibly due to current activity or substrate instability or both, and redirected its growth upward several times during life. It is the earliest North American solitary rugosan that had the ability to resume upward growth after being fully
overturned.
Notes on late Middle Ordovician gastropods from the Advance Formation, northeastern British Columbia
Authors: Rohr D M
Published: March 2017

Small gastropods from etched residues of rocks from the Advance Formation represent Liospira cf. L. vitruvia (Billings), Lophospira spp., Murchisonia sp., Ophiletina angularis Ulrich and Scofield, and a bellerophontacean with affinities to Bucania. The assemblage
indicates late Blackriveran to Shermanian age.
L'océan sans limites: la dorsale Juan de Fuca
Authors:   Department of Energy, Mines and Resources Canada
Published: March 2017

Two thousand metres below the surface of the Pacific Ocean off Canada's west coast is an underwater mountain range called the Juan de Fuca Ridge. Its steaming vents spew forth an abundance of molten minerals, supporting a unique ecosystem denied the privileges of
light. The video takes the viewer to this remote new world and examines its scientific significance.
Des tremblements de terre au Canada?
Authors:   Department of Energy, Mines and Resources Canada
Published: March 2017

Canadians are not immune from the threat of a major earthquake. This video looks at the causes of earthquakes, the risks, the consequences and the precautions. Everyone should know what to do in the event of an earthquake.
The Geological Survey of Canada, past and present
Authors:   Department of Energy, Mines and Resources Canada
Published: March 2017

Since its inception in 1842, the Geological Survey of Canada's mandate to provide basic geoscientific knowledge about the country has remained the same, even as the frontiers of knowledge and scientific tools have evolved. This fast-paced video follows the GSC's
development and introduces viewers to exciting new research programs.
Hidden heritage, mining Ontario's future
Authors:   Department of Energy, Mines and Resources Canada,   Ontario Ministry of Northern Development and Mines
Published: March 2017

Produced in co-operation with the Ontario Ministry of Northern Development and Mines, this video traces Ontario's rich geological heritage, giving a broad sense of the importance of the mineral industry in Ontario. The number of minerals and their diversity will
come as a surprise.
Lithoprobe, probing the earth
Authors:   Department of Energy, Mines and Resources Canada
Published: March 2017

Lithoprobe lets scientists study the Earth to an incredible depth of 40 kilometres below its surface. As a result we are gaining valuable new information about mineral resources, and the patterns which shaped, and are still shaping, the Earth. The video describes
this exciting new research and explains its economic and geological implications.
La science du changement
Authors:   Department of Energy, Mines and Resources Canada
Published: March 2017

This video looks at the Geological Survey of Canada's contribution to the international Global Change Program, and its attempt to assess the amount and the reasons for contemporary and future changes in our environment. Essential to this work is a solid grasp of
past environmental conditions and changes, which can only be found in the geological record.
Alternative methods of base map generation using remote sensing and GIS: a pilot study in the western Churchill Province, Northwest Territories
Authors: Wilkinson L , Budkewitsch P , Graham D F , Henderson J , D'Iorio M
Published: March 2017

In many regions of Canada, particularly in the North, digital base map information at 1:50000 scale is not available. Digital base maps generated from three sources (Landsat Thematic Mapper (TM), Landsat Multi-Spectral Scanner (MSS), and digitization of NTS
topographic sheets) are compared. Results indicate that Landsat-TM and manually digitized maps from 1:50 000 scale NTS (National Topographic System) map sheets provide similar resolution and accuracy at 1:50 000 scale. Landsat MSS data is comparable in accuracy to digital 1:250 000 scale data from
the National Topographic Database (NTDB). Despite the need for GIS or remote sensing software and expertise to run it, base map extraction from satellite images (Landsat TM, in particular) is quick and can provide valuable ancillary terrain information.
New mapping of Archean supracrustal rocks in the Kaminak Belt, District of Keewatin, Northwest Territories
Authors: Peterson T D
Published: March 2017

The Kaminak greenstone belt north of the Wallace River consists of two sequences of tuff, arenite, and iron-formation, separated by pillowed basalt and plagioclase-phyric andesite(?) with minor rhyolite tuff and autobreccia. Initial tight folding of S0, mainly at
greenschist and lower amphibolite facies but locally at migmatite grade (D1), was followed by more open folding at greenschist facies (D2). Syn-D2 intrusion of granite and tonalite dykes accompanied development of a large northeast-trending shear zone (Tavani shear zone). Minor folding and faulting
of D2 cleavage (D3) occurred at subgreenschist facies and predated emplacement of post-tectonic diorite-to-granite, assigned to the Snow Island suite, at about 2.60 Ga.
Geology and structure of parts of MacQuoid Lake map area, District of Keewatin, Northwest Territories
Authors: Tella S , LeCheminant A N , Sanborn-Barrie M , Venance K E
Published: March 2017

The map area is underlain by an Archean metavolcanic and metasedimentary sequence composed of mafic to felsic flows and tuffs intercalated with volcaniclastic rocks, greywacke, and iron-formation. Structural trends are predominantly east-northeast. They represent
composite fabrics developed during Archean and Paleoproterozoic, greenschist- to amphibolite-grade, polyphase tectonothermal events. The supracrustal rocks are intruded by late Archean syntectonic (D2) granitoid complexes and by relatively younger gabbro and ca. 1.8 Ga granite plutons.

Deformed and metamorphosed, east- to east-southeast-striking Paleoproterozoic diabase dyke swarms transect the supracrustal sequence and the deformed granitoids. The dykes provide markers for Paleoproterozoic tectonothermal overprint on Archean structures. Numerous southeast-trending, K-rich
lamprophyre, syenite, and quartz-feldspar porphyry dykes are widespread throughout the region. The lamprophyres and porphyry dykes postdate the metadiabase swarms, but predate the ca. 1.8 Ga granite plutons.

The region is currently being explored by industry for base metals, gold, and diamonds.
Last glacial ice flows over western Meta Incognita Peninsula, southern Baffin Island, Northwest Territories
Authors: Hodgson D A
Published: March 2017

Five ice flow domains from the last (late Foxe) glaciation are identified from field and airphoto examination of glacial bedforms and streamlined till: (1) southeast-flowing ice in Hudson Strait; (2) a strong southwest flow over much of western Meta Incognita
Peninsula, leaving little till; (3) a minor southwesterly readvance in mid-peninsula, responsible for a moraine belt; (4) a zone of conflicting ice flows north of the height of land, where the southwest flow likely reversed as ice drained from Frobisher Bay; (5) southeast flow in the Frobisher
Bay-Amadjuak Lake lowland. This pattern is incompatible with the existing deglacial chronology of retreat from Hudson Strait (in Domain 2) by 8.2 ka and the mid-peninsula readvance (Domain 3) interpolated at ca. 7.5 ka, while the Frobisher Bay moraines (Domain 5) date from an extended
readvance-stillstand between 8.7 and 6.6 ka.
Granite-greenstone terranes for the northern Minto block, northeastern Quebec: Pelican-Nantais, Faribault-Leridon, and Duquet belts
Authors: Percival J A , Skulski T , Nadeau L
Published: March 2017

Aeromagnetic images of the northern Minto block show broad (40-100 km) positive anomalies divided by narrow (10-20 km) linear þtroughsþ. Reconnaissance mapping reveals supracrustal remnants within the troughs, separated by pyroxene-bearing granitoid massifs.
Previous work in the þGoudalie trendþ documented the Vizien, Qalluviartuuq, and Duquet belts. To the east of the belts (80 km) is the 220-km long, segmented Pelican-Nantais belt of mafic, intermediate and felsic volcanic rocks and immature sedimentary rocks, metamorphosed at amphibolite and
granulite facies. The map pattern of the central part of the Pelican-Nantais belt resembles a regional-scale sheath fold. Reconnaissance in the Faribault-Leridon belts, 75 km farther to the east, showed mainly mafic volcanic rocks, gabbro, and some peridotite, associated with quartz-rich sedimentary
units. Plutonic units comprise variably pyroxene- or hornblende-biotite- bearing tonalite, granodiorite, and granite.
The initial phase of stream incision in the deposit of the April 1996 landslide near Saint-Boniface-de-Shawinigan, Quebec
Authors: Brooks G R , Aylsworth J M
Published: March 2017

A large retrogressive landslide (7 x 106 m3) occurred near Saint-Boniface-de-Shawinigan, Quebec, on April 21, 1996. The landslide debris flowed across the valley bottom of the Machiche River with some debris being transported several hundred metres downvalley.
The debris buried the bottom of the valley impounding Machiche River forming a lake up to 10 m deep. The river overtopped the landslide dam on April 28, and by May 30, the impoundment level had dropped about 50 cm. Surveying along the restored channel course revealed that the river flowed initially
across the surface of the landslide debris then entered a well-defined erosional channel which it followed downvalley. Up to 5.1 m of incision had occurred along the eroded portion of the channel. The incision along the eroded channel was situated downstream of the crest of the landslide debris and
thus had not affected the level of the impoundment.
Anatomy of a small intraplate rupture: definitely not a high stress drop event
Authors: Haddon R A W , Adams J
Published: March 2017

The magnitude mbLg = 5.0 Mont-Laurier earthquake of 19 October 1990, in Quebec, Canada, was one of the largest to have occurred in eastern North America during the past decade. High-frequency ground motions recorded on regional network instruments exceeded
anticipated values for an event of its size by a factor of 3. A commonly favored explanation for the discrepancy is that the source was a rare "high stress drop" event. In this article, detailed fault slip models are derived to fit waveform and spectral characteristics of the network data. The
results establish that the effective rupture stress was normal (less than 100 bars), that the fault rupture developed symmetrically,
and that the average slip time for points inside the rupture area ( approx. 0.1s) was significantly less than that associated with the standard Brune source spectral model. The rupture area developed in at least four distinct episodes, each extending the previously ruptured area. Taken together with
similar results for the mbLg = 6.5 Saguenay earthquake of November 1988, the results indicate that the widely-used assumption in hazard analyses that earthquake spectra are adequately represented by the standard Brune complete stress drop model is unreliable for the interpretation and prediction of
strong ground motion.
Carte morphostructurale du secteur central du chaînon Ruby, Yukon
Authors: Mbuluyo M K , Geurts M A
Published: March 2017

Based on the study of lineaments, this paper clarifies the role of tectonic structures on the geomorphology and river system development in southwestern Yukon. From the kinds of deformation and the observation of related landforms, two types of tectonism are
recognized. The first one is associated with the pre-Paleocene intrusion of granite bodies; the dome at the centre of the study area where the head of the major streams are located is related to it. The second one postdates the granites and consists of brittle fracturing that formed faults which
are used by the streams. During the Quaternary, the glaciers enlarged these pre-existing valleys. This neotectonism is still active in the region as evidenced by deformed Quaternary deposits.
Seismic reflection profiling in support of a deep borehole, Fraser River delta, British Columbia
Authors: Harris J B , Hillman R A , Hunter J A , Luternauer J L
Published: March 2017

Approximately 3 km of seismic reflection data have been obtained in order to map the structure of the bedrock (Tertiary) surface in an area surrounding a deep borehole drilled as part of a continuing earthquake hazards assessment of the Fraser River delta.
Seismic data quality was highly variable (even over relatively short distances) due primarily to the presence of gas in the shallow sediments. A map of two-way travel time suggests a northeast-trending bedrock channel beneath the area that is possibly fault controlled. The structure of the bedrock
surface beneath the delta has been identified as an important boundary for controlling ground motion amplification from seismic shaking. It is anticipated that this new information will be combined with the existing bedrock data set to further assemble a geological and geophysical framework of the
deep structure beneath the delta.
A problematic Early Cretaceous age for the conglomerates previously assigned to the Eureka Sound Group, east-central Ellesmere Island, Arctic Archipelago
Authors: de Freitasw T A , Sweet A , Thorsteinsson R
Published: March 2017

A conglomerate sequence more than 1 km thick was deposited in the footwall of the Parrish Glacier Thrust, in gravelly braided stream and alluvial fan settings. The conglomerate lithoclasts were derived from lower Paleozoic strata exposed in the hanging wall of
the thrust. Internal disconformities in the conglomerates adjacent to the main regional thrust and the klippe of Ordovician carbonate resting on the conglomerates, indicate that thrusting was synchronous with, and postdated, sedimentation.

Fossils from the conglomerate outlier are Early Cretaceous in age. The apparent lack of exposed Cretaceous deposits in the hanging wall and the extent of fine grained deposits from which the fossils were collected suggest their deposition was in situ. However, alluvial deposits of this type and age
are unknown in the Canadian Arctic, and conglomeratic outliers farther north have yielded Paleocene or younger fossils, thus placing the Cretaceous age assignment in question.
Petrophysical characteristics of limestone xenoliths in kimberlites from Kirkland Lake, Ontario
Authors: Katsube T J , Connell S , McClenaghan M B , Armstrong D K
Published: March 2017

Pore-size distribution has been determined by mercury porosimetry for six surface limestones, six diatreme-facies kimberlites, and six limestone xenoliths (from within the kimberlites) sampled from the Kirkland Lake (Ontario) area. The purpose was to investigate
how the petrophysical characteristics of limestone fragments change as a result of their mixing with kimberlite magma. Results indicate that while porosities of the xenolith core-material samples are higher than those of the parent limestones, the pore-size distribution patterns are similar,
suggesting that these distribution patterns may reflect textural features that are related to the source rock. In contrast, the rim-material samples of the limestone xenoliths show lower porosities than their cores, and display pore-size distribution patterns which are similar to those of the
kimberlite that hosted them. These distribution patterns most likely reflect alteration of the limestone xenoliths by the kimberlite magma.
Airborne gamma spectrometer-magnetic-VLF survey of northeastern Alberta
Authors: Charbonneau B W , Holman P B , Hetu R J
Published: March 2017

The survey (10 000 km2) presented at 1:250 000 scale, based on 1 km flight line spacing, comprises 12 colour geophysical maps, a geological mineral occurrence map, and a set of 146 stacked multiparameter profiles. The digitally recorded survey is ideal for
integration with other data sets acquired during this MDA and for geophysical modelling.

The radioelement distribution patterns provide significant information over the peraluminous igneous rocks. The thorium and uranium/thorium ratio map patterns are controlled by monazite which hosts most of the thorium and is generally accompanied by zircon. Uraninite and uranothorianite host most of
the uranium. The more thoriferous magmatic rocks are less evolved (lower differentiation index) and have greater amounts of biotite, monazite and zircon. The more evolved magmatic rocks (more felsic) generally have lower thorium concentrations, which corresponds to less monazite and zircon. Areas of
high potassium (with a low Th/K ratio) commonly relate to evolved granitoids although some anomalies may indicate potassium alteration.

Magnetic patterns relate to magnetite/ilmenite with some hematization of magnetite. The magnetic maps are particularly useful in outlining geological structure and faulting. VLF patterns correlate with fractures and high-grade metasedimentary bands and in places indicate sulphide-rich conductors.

Geophysical signatures have often been linked to processes which point to mineralization and potential exists for U, Mo, Cu, Sn, W, REE and Au. In northeastern Alberta such linkages are not currently recognized with the exception of VLF anomalies coincident with certain sulphide-rich metasedimentary
bands and uranium anomalies relating to some uranium occurrences. However, with further investigation of observed geophysical patterns, correlations with mineralized systems may be recognized.
Interpretation of geochemical data from lake sediments and waters over Precambrian rocks in northeastern Alberta
Authors: McCurdy M W
Published: March 2017

A lake sediment and water geochemical survey was carried out in 1994 in northeastern Alberta (parts of NTS 74E, L, and M) under the Canada-Alberta Mineral Development Agreement (1992-1995). Over an area of 22,100 km2, samples were collected from 1,160 sites.
Analytical results for 35 elements were published in a Geological Survey of Canada Open File.

Data for six economic metals (uranium, molybdenum, gold, zinc, nickel, and copper) and two "pathfinder" elements (arsenic and antimony) were contoured and plotted over a topographic base. The results, in conjunction with structural, bedrock and surficial geology, were used to determine areas where
detailed studies or follow-up exploration are warranted.

South of Lake Athabasca, in areas of thick overburden, glacial processes played a major role in the geochemical signature of the elements examined. North of Lake Athabasca, where overburden is thin or nonexistent, bedrock geology is the prime factor affecting geochemical results.

A number of areas have potential for further exploration. Particularly interesting is an area in the northwest where a number of east-trending faults intersect a north-trending fault. Uranium and gold values are high in lake sediments over this area of granitoids and high-grade metasediments. South
of Lake Athabasca, there are a number of areas that should be explored for the possibility of placer gold deposits, particularly along the Athabasca River and along the south shore of Lake Athabasca. An area of granitoid and mylonitic rocks in the southern part of the survey is recommended for
follow-up work for gold based on an unusually high antimony value.
Petrology and economic geology of the Crowsnest volcanics, Alberta
Authors: Peterson T D , Currie K L , Ghent E D , Bégin N J , Beiersdorfer R E
Published: March 2017

The Crowsnest Volcanics are lower Cretaceous (ca. 100 Ma) epiclastic and volcanic rocks exposed in west dipping, Tertiary thrust stacks in southwestern Alberta. Nearly all of the volcanic rocks are mildly potassic trachytes and phonolites (average 1.4 wt%
K2O/Na2O) with phenocrysts of sanidine, clinopyroxene, titanite, melanite, and analcite; apatite is abundant in some cumulate xenoliths. An unusual pyroclastic unit contains strongly potassic juvenile fragments rich in biotite, leucite (converted to potassium feldspar) and sulphides. In the
phonolites, fresh analcite, up to 3 cm in diameter has magmatic delta-18O (9.5 per mil), occurs as sealed inclusions in other phenocrysts, and has normal and reverse K and Fe zoning profiles that match associated sanidine phenocrysts. The analcite is interpreted as a primary high-pressure,
low-temperature phenocryst phase (ca. 7 kbar, 700°C). Whole rock samples do not display geochemical patterns, such as negative Eu anomalies, that are consistent with crystal fractionation of alkali or transitional basalt. Rare earth element (REE) patterns are highly fractionated with flat heavy
REE, consistent with equilibration with a garnet-rich residue. The markedly negative E-Nd composition and the bulk Earth- like Sr composition of Sr from the Crowsnest Volcanics resembles that of some strongly potassic rocks of the Churchill and Wyoming Archean provinces. The Crowsnest magmas
probably originated by partial melting of moderately metasomatized lithosphere, near the crust- mantle boundary (25-30 km). Primary gold and base metal concentrations are noneconomic; low-grade metamorphism did not produce anomalous vein or stratiform concentrations.
Diamonds in Alberta: studies of potential host rocks of deep-seated origin and applications of indicator mineral exploration techniques
Authors: Kjarsgaard B A
Published: March 2017

The recent identification of subsurface crystalline basement domains of Archean and Paleoproterozoic age in Alberta is geologically favourable for the occurrence of kimberlite- or lamproite-hosted diamond deposits. Throughout Alberta, diamonds and indicator
minerals have been recovered from various Quaternary glacial deposits and modern drainage systems, largely as a result of intensive diamond exploration prospecting since 1990. Recently, pipes containing crater-facies rocks have been discovered in the Grande Prairie area. These pipes, together with
strongly potassic igneous rocks exposed in the Milk River area, constitute the only currently known occurrences in Alberta of magmatic rocks of deep-seated origin that have the potential to be diamond-bearing. The "Sweet Grass Intrusives" outcrop as hypabyssal intrusive rocks (dykes, plugs) as well
as extrusive rocks in the Milk River area. Combined whole-rock major- and trace- element chemistry, and isotopic studies, coupled with petrographic studies and mineral chemistry, demonstrate that these rocks are minettes, which were derived from a veined, lithospheric mantle source region at
>100 km depth (i.e., P >30 kb; garnet lherzolite assemblage). Major- and trace-element chemistry of Cr-spinels from the Sweet Grass minettes indicate that existing classification and discrimination diagrams do not separate minette Cr-spinels from kimberlite or lamproite
Cr-sprinels. This is important, as Cr-spinel is used commonly in surficial diamond indicator mineral exploration programs in Alberta. Both the Hinton (central Alberta) and Legend (southern Alberta) areas, suggested to have high diamond potential, have complex sedimentological histories (multiply
recycled indicator minerals), and the primary source(s) of the diamonds and indicator minerals are still unknown.
Kimberlite indicator mineral and geochemical reconnaissance of southern Alberta
Authors: Thorleifson L H , Garrett R G
Published: March 2017

An indicator mineral and geochemical survey designed to examine diamond and metallic mineral potential, glacial sediment transport history, and both exploration and environmental geochemistry, was carried out in southern Alberta in 1992. Sampling sites were
randomly selected prior to field work, with two sites in 40 km x 40 km cells designated for sampling of till (unsorted glacial sediments) and soil, and additional sites designed to define local variability of soils. At 252 sites, a 25l sample of till was collected from 1 to 2 m depth from surface
exposures, mainly road cuts. Soil samples from the A and C horizons were obtained from 352 sites randomly distributed on all parent materials. Processing of the till samples, followed by mineralogical and chemical analysis, resulted in the confirmation of an average of one indicator mineral per two
samples. Several areas where favourable kimberlite indicator mineral results are clustered were defined. Additional lithological, mineralogical, and geochemical analyses of till were used to provide evidence of the bedrock source of the sediment. Sediment consisting of material transported generally
southwestward by Pleistocene glaciation radiating from the Canadian Shield can be distinguished from Pleistocene sediments north and south of Calgary which contain abundant material glacially transported from the Cordillera. The soil geochemical data are of less direct application to mineral
exploration than the till data, owing to variable texture and greater modification by pedological processes, but these data provide useful information of relevance to environmental and agricultural issues.
Geological setting and origin of microdissemiated Au-Ag-Cu minerals, Fort Mackay region, northeastern Alberta
Authors: Abercrombie H J , Feng R
Published: March 2017

Newly discovered gold, silver, copper and related metallic minerals occur in rocks of the Western Canada Sedimentary Basin and underlying Precambrian basement near Fort MacKay, Alberta. The minerals include microdisseminated native, intergrown, and alloyed
metals, and metal-chloride, -oxide, -carbonate, and -sulphide minerals deposited in pores and in microveinlets associated with fractures and diagenetically altered fabrics. Typical alteration minerals include hematite, microcrystalline quartz, Ce-carbonate, monazite, and native S.

A major structural feature at Fort MacKay is the dissolution edge of the Middle Devonian Prairie Formation, Upper Elk Point Group. Salt dissolution over a 20-30 km wide band paralleling the basin margin caused significant vertical displacement and collapse of overlying sediments. Three hydrochemical
zones are recognized: a lower, relatively oxidized, brine regime (>200 000 mg/l; Precambrian, Elk Point); an intermediate, relatively reduced, saline regime (10 000 to 70 000 mg/l; Beaverhill Lake, Woodbend); and an upper, fresh to brackish regime (1000 to 10 000 mg/l; Mannville and
younger), locally bitumen-saturated.

Microdisseminated polymetallic mineralization is proposed to have occurred by mobilization and transport of gold and other metals in oxidizing, halide-rich brines derived from the Elk Point Group at a maximum paleotemperature of about 90°C. Metal deposition probably is related to changes in
redox potential along the flow path; deposition may, in part, be related to the presence of hydrocarbons. The basin- wide distribution of halite in the Prairie Formation and its removal by dissolution over large areas of the WCSB may signify regional potential for similar occurrences across western
Canada.
Relationships between chemical composition, physical properties, and geology of the mineralized Emerald Lake Pluton, Yukon Territory
Authors: Duncan R A , Russell J K , Hastings N L , Anderson R G
Published: March 2017

Emerald Lake Pluton is a newly remapped member of the mid-Cretaceous Tombstone plutonic suite in Yukon. It is crudely concentrically-zoned comprising: augite syenite, hornblende quartz syenite, hornblende quartz monzonite, and biotite granite, from west to east
and in order of relative age. Density and magnetic susceptibility values of samples from each phase decrease, and Shand Indices increase, from west to east and correlate with mapped intrusive phases. The intrusion is also characterized by the presence of large miarolitic cavities distributed along
the southern and eastern margins of the intrusion. They are spatially and temporally associated with a sheeted system of aplite dykes, quartz K-feldspar pegmatites, and molybdenite bismuthinite gold quartz veins. Miarolitic cavity and pegmatite formation are coeval with the main intrusive events,
and were followed by continued pegmatite development, fracturing, and injection of aplite dykes and veins.
Progress report on bedrock geology of Lansing map area, central Yukon Territory
Authors: Roots C F
Published: March 2017

Regional mapping in 1996 and 1997 in western Lansing map area defined an upper Hyland Group succession, Cambrian submarine mafic volcanic accumulations, new exposures of Keno Hill quartzite, and several probable Permian and Triassic localities. The Robert Service
Thrust trends southeast across the map area as an overturned contact between Yusezyu Formation sandstone and green Permian argillite. Tombstone Thrust lies within recessive Earn Group shale in the northwest, and is linked to the dextral Macmillan Fault in eastern Lansing map area. Folded Upper
Paleozoic units along its south side imply that the fault formed the vertical northeastern boundary of the northwest-directed Tombstone thrust sheet.
Global Positioning System survey of ground-penetrating radar traverses of the ice cap, Hoodoo Mountain, British Columbia
Authors: Nicholls J , Page T , Schmok J , Russell J K , Stasiuk M
V
Published: March 2017

Three single-frequency GPS instruments were used to provide horizontal and vertical control for radar surveys of the ice cap on Hoodoo Mountain, British Columbia. Survey control was established by locating two survey control markers on a moraine at the edge of
the ice cap. The survey control markers were located relative to a B.C. Government horizontal control point approximately 6 km from the new survey control markers on Hoodoo Mountain. Vertical adjustment to height above the ellipsoid was accomplished by comparing survey control-marker data on Hoodoo
Mountain with GPS data collected by the British Columbia Active Control System (BC ACS) station at Dease Lake.