Browsing Earth and Environmental Sciences by Title
Now showing items 337-356 of 434
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Ra-228, Ra-226, Ra-224 and Ra-223 in potential sources and sinks of land-derived material in the German Bight of the North Sea: implications for the use of radium as a tracer
(Springer, 2011-08-01)Activities of the naturally occurring radium nuclides Ra-228, Ra-226, Ra-224 and Ra-223 were determined in waters of the open German Bight and adjacent nearshore areas in the North Sea, in order to explore the potential ... -
Radial Movement of a Passively Released Gas from a Monitoring Well
(University of Waterloo, 2009-09-01)In order to preserve groundwater as a viable source of drinking water, remedial measures must be applied where appropriate. The application of the various remedial technologies is site and contaminant dependent. Differing ... -
Rare earth elements and radiogenic strontium isotopes in carbonate minerals reveal diagenetic influence in shales and limestones in the Appalachian Basin
(Elsevier, 2019-03-30)Rare earth element (REE) signatures are often applied to interpret paleoenvironmental conditions in sedimentary basins, however the complicated diagenetic histories in dynamic depositional environments can affect interpretation ... -
Reconstruction of Local and Global Marine Paleoredox Conditions during Deposition of the Devonian-Mississippian Exshaw Formation (Black Shale Member) and the Evaluation of Hydrocarbon Maturation Effects
(University of Waterloo, 2019-07-17)The end-Devonian Hangenberg event represented one of the biggest Phanerozoic mass extinctions. However, the potential mechanism(s) for triggering this event, including climate cooling, sea-level change, glaciation and ocean ... -
Reconstruction of local and global marine paleoredox conditions for the northeast-Panthalassan (British Columbia, Canada) expression of the Toarcian Oceanic Anoxic Event using a multi-proxy approach
(University of Waterloo, 2020-01-23)The Toarcian Oceanic Anoxic Event (T-OAE) of the Early Jurassic is one of several Mesozoic instances of expanded ocean anoxia, coupled with feedbacks and perturbations in Earth’s systems. The drivers for these feedbacks ... -
Reconstruction of Local and Global Marine Redox Conditions During Deposition of Late Ordovician and Early Silurian Organic-Rich Mudrocks in the Siljan Ring District, Central Sweden
(University of Waterloo, 2016-01-12)The Ordovician-Silurian transition witnessed the second largest mass extinction in the Phanerozoic Eon and the Hirnantian glaciation. We measured U (as δ238U relative to standard CRM145 = 0‰) and Mo (as δ98Mo relative to ... -
Reconstruction of Paleoclimate Time-Series in the Peace-Athabasca Delta, Northern Alberta, from Stable Isotopes in Tree-Rings
(University of Waterloo, 2008-08-12)The isotopic labelling of carbon in tree-rings varies as a function of growth season temperature and relative humidity. The isotopic labelling of oxygen in tree-rings varies as a function of source-water isotopic composition ... -
Redox conditions across the Cambrian–Ordovician boundary: Elemental and isotopic signatures retained in the GSSP carbonates
(Elsevier, 2015-12-15)Lime mudstone samples (rhythmites) were collected at high resolution from outcrops of the Cambrian–Ordovician GSSP boundary section at Green Point (western Newfoundland, Canada). The sequence (~45 mthick) consists of slope ... -
Reduction of TCE and Chromate by Granular Iron in the Presence of Dissolved CaCO<sub>3</sub>
(University of Waterloo, 2006)Iron permeable reactive barriers (PRBs) have been installed at sites contaminated with various reducible organic and inorganic chemicals, particularly chlorinated solvents, worldwide. Many geochemical factors can affect ... -
The relationship between retail type and transportation emissions
(University of Waterloo, 2013-09-03)This study investigates the relationship between three types of retail, Big Box, traditional and online retail, and their transportation related emissions. The study takes a comprehensive approach by examining both the ... -
Remediation of Pentaerythritol Tetranitrate (PETN) Contaminated Water and Soil
(University of Waterloo, 2007-11-28)Pentaerythritol tetranitrate (PETN), a nitrate ester, is widely used as a powerful explosive and is classified as a munitions constituent of great concern by DoD in U.S.A. It is an environmental concern and poses a threat ... -
Remote Paleohydrograph Reconstruction of the Stockton Island Tombolo
(University of Waterloo, 2021-05-01)Rising lake levels have become a concern for the coasts of Lake Superior and one such coastline is the Stockton Island Tombolo (SIT) that protects the Pine Barrens Habitat (PBH) in the Apostle Islands National Lakeshore ... -
Removal of Arsenic and Metals from Mine-impacted Groundwater Using Organic Carbon and Zero-valent Iron in Passive Remediation Systems
(University of Waterloo, 2020-09-21)Arsenic (As) is a wide-spread contaminant, often encountered in drainage associated with Au mining. The oxidation state controls the mobility and toxicity of As in water. Passive remediation is a potential management ... -
Removal of Perchlorate, Pharmaceutical Compounds, Artificial Sweeteners, and Perfluoroalkyl Substances from Water Using Photocatalytic and Passive Treatment Systems
(University of Waterloo, 2017-07-12)The persistence and widespread occurrence of emerging contaminants (ECs) such as perchlorate (ClO4-), pharmaceutical compounds, artificial sweeteners, and perfluoroalkyl substances in the environment has received increasing ... -
Removal of pharmaceutical compounds, artificial sweeteners, and perfluoroalkyl substances from water using a passive treatment system containing zero-valent iron and biochar
(Elsevier, 2019-11-15)Emerging contaminants are widely detected and persistent in environmental waters. Advanced oxidation processes are among the most effective methods for removing emerging contaminants from water; however, high energy ... -
Rescuing Historical Climate Observations to Support Hydrological Research: A Case Study of Solar Radiation Data
(ACM, 2021-08-16)The acceleration of climate change and its impact highlight the need for long-term reliable climate data at high spatiotemporal resolution to answer key science questions in cold regions hydrology. Prior to the digital ... -
Reservoir Geomechanics and Casing Stability, X1-3Area, Daqing Oilfield
(University of Waterloo, 2007-01-24)It is widely understood that injection and production activities can induce additional stress fields that will couple with the in situ stress field. An increased shear stress may cause serious casing stability issue, and ... -
Reservoir screening criteria for deep slurry injection
(University of Waterloo, 2005)Deep slurry injection is a process of solid waste disposal that involves grinding the solid waste to a relatively fine-grained consistency, mixing the ground waste with water and/or other liquids to form slurry, and disposing ... -
A Rock Borehole Packer System for Identifying Hydraulically Active Fractures Under Natural Gradient Flow
(University of Waterloo, 2008-05-27)To improve capabilities for understanding and predicting contaminant migration in fractured rock there is need for better field methods to identify the fractures that have active groundwater flow. Current methods have ... -
The Role of Nitrate in Controlling Iron Release from Sediment during Anoxia in Dimictic, Fresh Water Lakes
(University of Waterloo, 2018-01-16)Recent research suggests the availability of reduced iron (Fe) is key in allowing cyanobacteria to outcompete eukaryotic phytoplankton. Cyanobacteria have a greater need for Fe than their eukaryotic competition and are ...