Browsing Earth and Environmental Sciences by Title
Now showing items 107-126 of 434
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Evaluating Vadose Zone Moisture Dynamics using Ground-Penetrating Radar
(University of Waterloo, 2012-02-27)Near-surface sediments in the vadose zone play a fundamental role in the hydrologic system. The shallow vadose zone can act as a buffer to delay or attenuate surface contaminants before they reach the water table. It also ... -
Evaluation of an Oxygen Injection Technology for In-Situ Hydrocarbon Bioremediation in a Fractured Bedrock Environment
(University of Waterloo, 2009-04-30)Oxygen has been shown to be an effective addition of enhancing the bioremediation of petroleum hydrocarbon contamination in porous media; however, the ability to effectively deliver oxygen to petroleum hydrocarbon contaminated ... -
Evaluation of baseflow estimation methods with real and synthetic streamflow data from a watershed
(University of Waterloo, 2022-01-25)Baseflow with origins from groundwater is a critical component of streamflow sustaining it throughout the year especially during dry periods. To better understand the role of baseflow in streamflow, accurate estimates are ... -
Evaluation of Geochemical and Reactivity Changes of Different Iron Materials
(University of Waterloo, 2006)Previous studies have suggested that iron PRBs, receiving high concentrations of inorganic constituents in groundwater, may experience passivation because of the accumulation of inorganic precipitates. In an iron PRB ... -
Evaluation of Hydraulic Conductivity Collected by Various Approaches at a Highly Heterogeneous Field Site
(University of Waterloo, 2023-01-27)Significant research efforts have been conducted over the last several decades to better understand the groundwater flow and subsurface contaminant transport. It has been found that building a groundwater model for remediation ... -
Evaluation of mercury stabilization mechanisms by sulfurized biochars determined using X-ray absorption spectroscopy
(Elsevier, 2018-04-05)The application of biochar to treat mercury (Hg) in the environment is being proposed on an increasing basis due to its widespread availability and cost effectiveness. However, the efficiency of Hg removal by biochars is ... -
Evaluation of Stable Chlorine and Bromine Isotopes in Sedimentary Formation Fluids
(University of Waterloo, 2008-05-21)Two new analytical methodologies were developed for chlorine and bromine stable isotope analyses of inorganic samples by Continuous-Flow Isotope Ratio Mass Spectrometry (CF-IRMS) coupled with gas chromatography (GC). ... -
Evaluation of the Potential Impacts of Submerging the Oxidized Tailings and Adding a Cover Layer at Mine Principale
(University of Waterloo, 2024-04-24)Oxidation of sulfide minerals generates acid and forms various secondary phases including Fe(III) (oxy)hydroxide phases, jarosite, and gypsum, which can attenuate hazardous metal(loid)s by precipitation, co-precipitation, ... -
Evaluation of the Removal of Perfluoroalkyl Substances from Aqueous Matrices in the Presence of Zerovalent Iron
(University of Waterloo, 2018-01-17)Per- and polyfluoroalkyl substances (PFASs) are a class of persistent organic pollutants present in the environment that pose a threat to human health. PFASs primarily reside within aqueous phases and are present in ... -
Evaluation of Traditional Hydrogeologic Characterization Approaches in a Highly Heterogeneous Glaciofluvial Aquifer/Aquitard System
(University of Waterloo, 2009-05-22)The purpose of this study was to evaluate the effectiveness of traditional hydrogeologic characterization approaches in a highly heterogeneous glaciofluvial aquifer at the North Campus Research Site (NCRS), situated on the ... -
Evidence for Participation of Anammox in Nitrogen Attenuation Observed in Groundwater Impacted by a Manure Lagoon
(University of Waterloo, 2012-01-23)Decades of agricultural use of fertilizer and manure has resulted in nitrogen being the most common groundwater contaminant. Of the known processes for nitrogen attenuation, both denitrification and anammox produce a ... -
Evolution of Canadian Shield Groundwaters and Gases: Influence of Deep Permafrost
(University of Waterloo, 2008-09-24)Numerous glacial advances over the past 2 million years have covered the entire Canadian and Fennoscandian Shield outcrop. During glacial advance and retreat, permafrost is expected to form in front of the glacier. The ... -
EVOLUTION OF LAKE ERIE BASED ON THE POSTGLACIAL SEDIMENTARY RECORD BELOW THE LONG POINT, POINT PELEE, AND POINTE-AUX-PINS FORELANDS
(University of Waterloo, 2016-09-27)The postglacial geological history of Lake Erie was interpreted primarily on the basis of borehole sedimentary sequences below the major accretionary forelands: Long Point, Point Pelee, and Pointe-aux-Pins. These data ... -
EVOLUTION OF MULTI-ARC ACCRETION SYSTEMS: A CASE STUDY FROM THE SOUTHERN BEISHAN OROGEN, CENTRAL ASIAN OROGENIC BELT, NW CHINA
(University of Waterloo, 2023-12-18)The Central Asian Orogenic Belt (CAOB) is characterized as an accretionary orogen, evolved for ca. 800 m.y from late Mesoproterozoic to early Mesozoic. Its terminal collision and accretion generally commenced in the west ... -
Evolution of the Laurentide Ice Sheet in north-central Ontario from subglacial sediments
(University of Waterloo, 2024-03-12)Till stratigraphic analysis of 10 sediment bluffs near Ogoki Post in the Hudson and James Bay Lowlands. -
Ex-situ dissolution of CO2 for carbon sequestration
(Elsevier, 2013)In this paper, a model for diffusion-controlled dissolution of CO2 droplets during co-current (CO2-brine) horizontal turbulent pipe flow is presented. The objective is to evaluate the feasibility of ex-situ dissolution of ... -
Examining Hydrogeological Processes in Freezing Soils using Remote Geophysical and Numerical Techniques
(University of Waterloo, 2019-02-11)The work presented in this thesis aimed to demonstrate the use of remote geophysical methods and numerical modelling to address questions related to hydrogeological processes in freezing soils. Two different study areas ... -
An expanded shale δ98Mo record permits recurrent shallow marine oxygenation during the Neoarchean
(Elsevier, 2020-01-20)Multiple attempts have been made using the ancient shale record to track the molybdenum isotope composition (δ98Mo) of seawater during the final two-hundred million years of the Archean Eon (2.7 to 2.5 billion-years-ago, ... -
Experimental determination of the extent of Fe(III) reduction and Fe isotope fractionation during microbial reduction of ferrihydrite in freshwater systems by sulfate-reducing bacteria
(University of Waterloo, 2017-12-15)Traditionally, sulfur was thought to have little influence on Fe cycling in freshwater systems because of the low sulfate concentrations (average ~ 0.2 mM) in such waters. However, a recent study suggested that a cryptic ... -
Extensive marine anoxia during the terminal Ediacaran Period
(American Association for the Advancement of Science, 2018-06-20)The terminal Ediacaran Period witnessed the decline of the Ediacara biota (which may have included many stemgroup animals). To test whether oceanic anoxia might have played a role in this evolutionary event, we measured U ...