The Liard Basin, in northwestern Canada, contains one of Canada’s largest natural gas reserves. There are concerns about degradation Dunvegan Formation groundwater quality, which is the basin's main shallow freshwater aquifer, as a consequence oil and development. Previous lithostratigraphic studies interpreted conglomeratic alluvial fans. In this study, newly collected cores surface resistivit...

• Coupled topography- and salinity-driven groundwater flow is studied on basin-scale. Increase in salinity/anisotropy weakens the topography-driven forced convection. Permeability/dispersivity modify coupling between salt- freshwater zones. Flow salt transport are revealed separated aquifers through faults. Mixed topohaline convection evolves a basin-scale system. Salinization of has endangered...

Determination of oxidation states of solid-phase arsenic in bulk sediments is a valuable step in the evaluation of its bioavailability and environmental fate in deposits, but is difficult when the sediments have low arsenic contents and heterogeneous distribution of arsenic species. As K-edge X-ray absorption near-edge spectroscopy (XANES) was used to determine quantitatively the oxidation stat...

Groundwater systems in the intermediate to deep subsurface of southern Ontario are poorly understood, despite their value for a number societal uses. A regional hydrostratigraphic framework is necessary precursor improving our understanding groundwater and enabling development 3-D model visualize these systems. This study compilation integration published unpublished geological, hydrogeological...

Dike failure due to piping – concentrated flow of seepage water underneath the dike during periods high flood levels has been recognized as a major component risk. Simulation models predict in risk assessments require detailed information on subsurface characteristics such sediment grain size and thickness overburden layers. Quantitative local determination these poses challenge natural environ...

Pedological studies in thick sedimentary sequences are generally limited to the upper few meters. Field investigation of thick (~50 m) sand deposits on an emergent Pleistocene marine terrace in central California showed morphological differences between the solum at the surface and the deep regolith. Based on morphological and geochemical features, four units were identified within the regolith...

The Theis equation has been widely used to study the transient movement of groundwater as a result of pumping in a confined aquifer. It is well known that the observed drawdown at early times has an obvious departure from the theoretical drawdown based on the Theis equation. The Theis equation was derived under the assumption that total stress in the aquifer was constant and the mechanical beha...