Engineering Geology Aspects Relating to Preliminary Damsite Investigations on the Nelson River, Manitoba

1972 ◽  
Vol 9 (3) ◽  
pp. 304-313 ◽  
Author(s):  
Douglas R. Piteau
Keyword(s):  
Engineering Geology ◽  
Preliminary Investigation ◽  
Seismic Refraction ◽  
Hudson Bay ◽  
Dolomitic Limestone ◽  
Lower Reach ◽  
Geologic Mapping ◽  
Precambrian Rocks ◽  
Discontinuous Permafrost ◽  
Basal Till

Engineering geology aspects of the preliminary investigation of nine alternative damsites along the lower reach of the Nelson River between Split Lake and Hudson Bay, Manitoba, Canada are described.Glacial drift, comprising mainly ablation and basal till, almost completely blankets the area, and active slope failures are common. The western part of the area is underlain by Precambrian rocks, which in the eastern part of the area are overlain by Paleozoic dolomitic limestone. Discontinuous permafrost conditions particularly presented some interesting terrain and investigation problems.The engineering geology studies included airphoto interpretation, both reconnaissance and detail geologic mapping, trenching, drilling, seismic-refraction surveys, river soundings, and ground surveys.

Stratigraphic Analysis with Refraction Tomography

2019 ◽  
Vol 25 (3) ◽  
pp. 245-254
Author(s):  
Peter J. Hutchinson ◽  
Maggie H. Tsai
Keyword(s):  
Seismic Refraction ◽  
High Energy ◽  
P Wave ◽  
Tidal Channels ◽  
Near Surface ◽  
Precambrian Rocks ◽  
Stratigraphic Analysis ◽  
P Wave Velocity ◽  
Refraction Tomography ◽  
Near Shore

ABSTRACT Near-surface seismic refraction tomography imaged the basal contact of the Upper Cambrian silica-rich Mount Simon Formation with that of the underlying Precambrian granite in central Wisconsin. The discrimination between the Mount Simon and underlying non-conformable contact with Precambrian rocks was based upon a p-wave velocity of 1,700 m/s. Refraction tomography imaged deep, broad tidal channels within the Mount Simon consistent with the inference that Mount Simon was deposited in a high-energy near-shore, probably fluvial environment. The Mount Simon is an arenite that has high commercial value.

Détermination de la géométrie et des propriétés physiques du pergélisol discontinu de la région de Schefferville

1977 ◽  
Vol 14 (3) ◽  
pp. 431-443 ◽  
Author(s):  
Maurice K.-Seguin
Keyword(s):  
Electrical Resistivity ◽  
Regional Scale ◽  
Seismic Refraction ◽  
Geophysical Methods ◽  
Near Surface ◽  
Vertical Extension ◽  
Discontinuous Permafrost ◽  
Propriétés Physiques ◽  
Lower Limits

The various parameters used to predict on a regional scale the lateral and vertical extension of permafrost are the following: surface temperature, thermal conductivity of rocks, and geothermal flow configuration. Locally this type of data is generally not sufficient and far too inaccurate. The use of geophysical methods at the surface and in boreholes in addition to existing thermal data helps to improve the degree of accuracy in the prediction of spatial distribution of permafrost in a given area. These geophysical methods include seismic refraction, electrical resistivity, and spontaneous and induced polarizations.Because of the properties of permafrost, seismic refraction at surface is useful only to determine the top of the permafrost whereas electrical resistivity (electric logging near surface) allows the determination of the upper and lower limits of permafrost. Seismic refraction, resistivity, and spontaneous and induced polarizations in boreholes were deemed more promising to determine masses or lenses of permafrost.Moreover, it was possible to correlate temperature and electrical resistivity measurements in boreholes, thus allowing the drawing of isothermal curves from electric logging in areas of continuous and discontinuous permafrost, at least when it is 'marginal'.The data for this study were obtained from the experimental station at Schefferville, Québec. [Journal Translation]

The evolution of permafrost in the taiga and in the forest–tundra, western Quebec–Labrador Peninsula

1976 ◽  
Vol 6 (2) ◽  
pp. 203-220 ◽  
Author(s):  
Serge Payette ◽  
Hélène Samson ◽  
Daniel Lagarec
Keyword(s):  
Developmental Stages ◽  
Hudson Bay ◽  
James Bay ◽  
Forest Tundra ◽  
Discontinuous Permafrost ◽  
Latitudinal Shift ◽  
Shrub Tundra ◽  
Forest Microclimate ◽  
Southern Section ◽  
Peat Plateaus

Major permafrost landforms of the discontinuous permafrost zone of Hudson Bay and James Bay, Quebec–Labrador Peninsula, are described and interpreted within an ecological perspective. These landforms are not fossil permafrost bodies; they are presently evolving under aggrading and degrading developmental stages. Permafrost peat complexes and permafrost mineral complexes are differentially distributed in the midtaiga, the forest–tundra, and the shrub–tundra zones of the study area. The wooded palsa complex is the most obvious permafrost complex in the midtaiga, and the palsa complex in the forest–tundra: The wooded palsa complex is related to the forest chronosequence, whereas the palsa complex, farther north, occurs where there is a suitable macroclimate for permafrost aggradation without the influence of cool forest microclimate. The wooded cryogenic mound complex in mineral landform is mainly distributed in the southern section of the forest–tundra and near the Hudson Bay shore; the cryogenic mineral mound complex is found in the northern section. The latitudinal shift of the northern complex is necessary for permafrost initiation in open sites. Degrading stages associated with thermokarst activity are similar for all these landforms and it is suggested that palsa complex is made of incipient, mature, and residual palsas whether they belong to palsa mounds or to peat plateaus. Similar conclusions are valid for cryogenic mineral mound complex.

A Review of Past Geotechnical Performance of the Hudson Bay Rail Embankment and Its Comparison to the Current Condition

2015 ◽  
Author(s):  
Priscilla E. Addison ◽  
Thomas Oommen ◽  
Pasi Lautala
Keyword(s):  
Engineering Properties ◽  
Peat Bogs ◽  
Hudson Bay ◽  
Maintenance Costs ◽  
The Past ◽  
Warming Climate ◽  
Discontinuous Permafrost ◽  
Continuous Permafrost ◽  
Geothermal Regime ◽  
Review Reports

The Hudson Bay Railway (HBR) is a 510 mile railway completed in 1929 in northern Manitoba, Canada. It connects domestic locations in North America with international destinations through the Port of Churchill. Permafrost was encountered during construction at milepost 136 in isolated peat bogs which continued in a gradual northward transition from discontinuous to continuous permafrost. Over the past 80 years, warming climate combined with poor engineering properties of the railway embankment material has resulted in further thawing of the discontinuous permafrost leading to differential settlement along the rail embankment and high annual maintenance costs. In a bid to understand the geothermal regime of the embankment, underlying subsurface condition, and to seek for solutions to stabilize the embankment, extensive work has been done from 1977 to the present time. This paper seeks to review reports of the past projects and compare the results against current conditions at selected test locations.

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