Browsing Earth and Environmental Sciences by Title
Now showing items 267-286 of 434
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Monitoring the evolution and migration of a methane gas plume in an unconfined sandy aquifer using time-lapse GPR and ERT
(Elsevier, 2017-08-01)Fugitive methane (CH4) leakage associated with conventional and unconventional petroleum development (e.g., shale gas) may pose significant risks to shallow groundwater. While the potential threat of stray (CH4) gas in ... -
Multi-decade comparison of groundwater nitrate in the southern Nottawasaga River Watershed
(University of Waterloo, 2016-08-25)The Nottawasaga River Watershed is host to the Lake Algonquin Sand Aquifer (LASA), an unconfined aquifer that consists of glaciolacustrine sands and provides water supply to rural residents, for household use, and for ... -
A multi-isotope approach towards constraining the origin of large-scale Paleoproterozoic B-(Fe) mineralization in NE China
(Elsevier, 2017-05-01)Borate ore deposits occur predominantly in Phanerozoic evaporative sedimentary environments but are scarce in Precambrian strata. However, massive B- and Mg-rich borate deposits are abundant in the Paleoproterozoic strata ... -
Multi-Phase Multi-Component Equilibrium Flash Calculations for CompFlow Bio using Modified Volume-Translated Peng- Robinson Equation of State
(University of Waterloo, 2017-05-24)Numerical modelling of fluid flow and transport in reservoir engineering problems is a challenging task, given variability and uncertainty in the physical properties of rock, the complexities of multi-fluid interaction at ... -
A Multi-Proxy Study of Holocene Atmospheric Circulation Dynamics Recorded in Lake Sediments in Fennoscandia
(University of Waterloo, 2009-01-22)Cellulose-inferred lake water oxygen-isotope records were obtained from five throughflow lakes situated along a north-south transect across Fennoscandia to help develop a better picture of Holocene changes in atmospheric ... -
A Multi-Scale Approach in Mapping the Sedimentological and Hydrostratigraphical Features of Complex Aquifers
(University of Waterloo, 2009-12-22)Accessibility to consistent subsurface hydrostratigraphic information is crucial for the development of robust groundwater flow and contaminant transport models. However, full three-dimensional understanding of the ... -
Multiple negative molybdenum isotope excursions in the Doushantuo Formation (South China) fingerprint complex redox-related processes in the Ediacaran Nanhua Basin
(Elsevier, 2019-09-15)The Ediacaran Doushantuo Formation offers one of the most complete and extensively studied records of end- Neoproterozoic biotic and environmental change. Here, we report multiple coeval negative molybdenum (Mo) ... -
NAPL Recovery Using CO<sub>2</sub>-Supersaturated Water Injection: Distribution of the CO<sub>2</sub> Gas Phase
(University of Waterloo, 2006)Gas inFusion? is a novel remedial technology that dissolves CO<sub>2</sub> into water under pressure for NAPL recovery. As the supersaturated liquid flows through the porous medium gas evolution occurs in situ as the ... -
Natural Gradient Tracer Tests to Investigate the Fate and Migration of Oil Sands Process-Affected Water in the Wood Creek Sand Channel
(University of Waterloo, 2009-10-02)The In Situ Aquifer Test Facility (ISATF) has been established on Suncor Energy Inc’s (Suncor) oil sands mining lease north of Fort McMurray, Alberta to investigate the fate and transport of oil sands process-affected (PA) ... -
Natural Late Holocene lake level fluctuations recorded in the Ipperwash strandplain, southern Lake Huron
(University of Waterloo, 2017-09-25)The Laurentian Great Lakes (LGL) are the largest system of surface freshwater on Earth. Three factors, glacial isostatic adjustment (GIA), outlet conveyance, and climate processes contribute to natural rises and falls in ... -
Natural source zone depletion of petroleum hydrocarbons under variable temperature and moisture conditions
(University of Waterloo, 2023-02-15)In subsurface environments contaminated by petroleum hydrocarbons (PHCs), the steep geochemical and redox gradients near the water table, the oxygen availability, moisture content, salinity, pH, nutrient concentrations and ... -
New Approaches to the Collection and Interpretation of High Sensitivity Temperature Logs for Detection of Groundwater Flow in Fractured Rock
(University of Waterloo, 2012-08-20)The use of temperature logging for identifying water flow through fractures in sedimentary rock has declined since the 1960’s and 70’s primarily because of low sensor resolution and cross-connected flow along the borehole. ... -
Nickel Isotope Geochemistry in Mine Waste System
(University of Waterloo, 2021-01-13)Metal stable isotope analyses have proven to make valuable contributions to the study of the biogeochemical cycling of metals and metalloids in the environment. Processes that control the release, mobility and fate of ... -
Nitrate sources and cycling at the Turkey Lakes Watershed: A stable isotope approach
(University of Waterloo, 2004)<p class=MsoNormal><span style="mso-spacerun: yes"> </span>Stable isotopic analysis of nitrate (<sup>15</sup>N/<sup>14</sup>N and <sup>18</sup>O/<sup>16</sup>O) was used to trace nitrate sources and cycling under ... -
The Nitrogen Legacy: Understanding Time Lags in Catchment Response as a Function of Hydrologic and Biogeochemical Controls
(University of Waterloo, 2016-09-23)Global population has seen a more than threefold increase over the last 100 years, accompanied by rapid changes in land use and a dramatic intensification of agriculture. Such changes have been driven by a great acceleration ... -
Nitrous oxide and nitrate in the Grand River, Ontario: Sources, production pathways and predictability
(University of Waterloo, 2013-12-13)The increased use of synthetic nitrogen fertilizers since the early 1900s has resulted in greater food production but also problems with nitrogen pollution in freshwaters. Nitrate (NO3-) is a common pollutant in rivers and ... -
Nitrous Oxide Production in the Grand River, Ontario, Canada: New Insights from Stable Isotope Analysis of Dissolved Nitrous Oxide
(University of Waterloo, 2008-10-07)Nitrous oxide (N₂O) is a powerful greenhouse gas, and its atmospheric concentration is increasing dramatically. N₂O is produced through the microbially-mediated processes of nitrification and denitrification. Since these ... -
NO3- and N2O at the Strawberry Creek Catchment: tracing sources and processes using stable isotopes
(University of Waterloo, 2008-08-26)Nitrate (NO3) contamination in agricultural watersheds is a widespread problem that threatens local drinking supplies and downstream ecology. Dual isotopes of NO3- (d15N and d18O) have been successfully used to identify ... -
Numerical investigation of the geophysical response to methane migration in an unconfined aquifer with implications for hydrocarbon wellbore leakage
(University of Waterloo, 2018-05-10)Methane gas leakage from oil and gas development can impact freshwater aquifers. Accurate depictions of gas migration in the subsurface will depend on knowledge of physical parameters and flow system conditions. Geophysical ... -
Numerical Modeling of Financially Sustainable Urban Wastewater Systems
(University of Waterloo, 2016-08-02)A system dynamics model first developed using the software Stella 7.0.2, which explores the complex behavior of the financially sustainable management of water distribution infrastructure, was converted here into a system ...