Greg A. Oldenborger

Results of recent VTEM helicopter system development testing over the Spiritwood Valley aquifer, Manitoba

Jean M. Legault, Alexander Prikhodko, James C. Macnae, Greg A. Oldenborger

The most recent VTEM system development is designed to achieve fully calibrated time-domain EM decay for better near-surface mapping than was possible with previous VTEM systems. The new design, known as the "full waveform VTEM system" uses the streamed half-cycle recording of …

au, ca (code pays fourni par la source)

Ground ice content of the frozen active layer and near-surface permafrost in the Rankin Inlet area, Nunavut, Canada

Benoit Faucher, A -M LeBlanc, Greg A. Oldenborger, Emmanuel Carrière et autres

In the context of climate change, the distribution and amount of ground ice in permafrost is critical to evaluate surface disturbances and geohazard risks.Ground ice conditions are poorly defined in northwestern Hudson Bay in the central Canadian Arctic, an area with renewed …

ca (code pays fourni par la source)

Time-domain electromagnetic soundings for talik investigations, Rankin Inlet, Nunavut

Greg A. Oldenborger

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Best practices for using electrical resistivity tomography to investigate permafrost

Teddi Herring, Antoni G. Lewkowicz, Christian Hauck, Christin Hilbich et autres

Abstract Electrical resistivity tomography (ERT) is a minimally invasive geophysical method that produces a model of subsurface resistivity from a large number of electrical resistance measurements. Strong resistivity contrasts usually exist between frozen and unfrozen earth materials, making ERT an effective and …

ca, ch, us, pt, de (code pays fourni par la source)

Hydraulic conductivity estimation and lithological classification of an esker aquifer system using surface electrical resistivity surveys and a neural network

Greg A. Oldenborger, Daniel Paradis

Empirical and theoretical relationships between hydraulic conductivity, lithology, and electrical resistivity provide a basis for the use of electrical resistivity for aquifer characterization in unconsolidated sediments. This study demonstrates a meaningful field-scale correlation between vertically distributed hydraulic conductivity obtained from packer-based borehole …

ca (code pays fourni par la source)

Permafrost thaw sensitivity prediction using surficial geology, topography, and remote-sensing imagery: a data-driven neural network approach

Greg A. Oldenborger, N Short, A -M LeBlanc

Seasonal or degradational thaw subsidence of permafrost terrain affects the landscape, hydrology, and sustainability of permafrost as an engineering substrate. We perform permafrost thaw sensitivity prediction via supervised classification of a feature set consisting of geological, topographic, and multispectral variables over continuous …

ca (code pays fourni par la source)

Landform mapping, elevation modelling, and thaw subsidence estimation for permafrost terrain using a consumer-grade remotely-piloted aircraft

Greg A. Oldenborger, O Bellehumeur-Génier, A -M LeBlanc, Isabelle McMartin

We assess performance of a small consumer-grade remotely-piloted aircraft (RPA) for landform mapping, elevation modelling, and thaw subsidence estimation in continuous permafrost terrain. We acquired RPA imagery near Rankin Inlet, Nunavut, to construct orthomosaics and digital elevation models (DEMs) that we use …

ca (code pays fourni par la source)

Borehole electrical resistivity, Vars-Winchester esker aquifer, Ontario

Greg A. Oldenborger

ca (code pays fourni par la source)

Electrical resistivity surveys, Vars-Winchester esker aquifer, Ontario

Greg A. Oldenborger

ca (code pays fourni par la source)

Multispectral permafrost terrain classification, Rankin Inlet, Nunavut

Greg A. Oldenborger, Benoit Faucher, A -M LeBlanc

ca (code pays fourni par la source)

Subzero temperature dependence of electrical conductivity for permafrost geophysics

Greg A. Oldenborger

ca (code pays fourni par la source)

Electrical conductivity and ground displacement in permafrost terrain

Greg A. Oldenborger, N Short, A -M LeBlanc

ca (code pays fourni par la source)