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Isolating Retrograde And Prograde Rayleigh-Wave Modes Using A Polarity Mute, Gabriel Gribler, Lee M. Liberty, T. Dylan Mikesell, Paul Michaels 2016 Boise State University

Isolating Retrograde And Prograde Rayleigh-Wave Modes Using A Polarity Mute, Gabriel Gribler, Lee M. Liberty, T. Dylan Mikesell, Paul Michaels

Geosciences Faculty Publications and Presentations

Estimates of S-wave velocity with depth from Rayleigh-wave dispersion data are limited by the accuracy of fundamental and/or higher mode signal identification. In many scenarios, the fundamental mode propagates in retrograde motion, whereas higher modes propagate in prograde motion. This difference in particle motion (or polarity) can be used by joint analysis of vertical and horizontal inline recordings. We have developed a novel method that isolates modes by separating prograde and retrograde motions; we call this a polarity mute. Applying this polarity mute prior to traditional multichannel analysis of surface wave (MASW) analysis improves phase velocity estimation for fundamental ...


High-Resolution Signatures Of Oxygenation And Microbiological Activity In Speleothem Fluid Inclusions, Nigel Blamey, Penelope J. Boston, Laura Rosales-Lagarde 2016 New Mexico Institute of Mining and Technology

High-Resolution Signatures Of Oxygenation And Microbiological Activity In Speleothem Fluid Inclusions, Nigel Blamey, Penelope J. Boston, Laura Rosales-Lagarde

International Journal of Speleology

Speleothems frequently host “fossil” fluids that were trapped in small inclusions during growth. Such fluids may provide valuable clues to past microbial, geochemical, and climatic processes during their formation. However, one difficulty is to understand which gases represent background atmosphere and fluids within a given cave system at a particular time, and which may be the product of post-trapping residual microbial activity or abiotic chemical reactions? Do we have any hope of sorting out these differences? The success depends on a quantitative understanding of the gas composition trapped in the inclusions and an understanding of the interactions of cave mineralogy ...


Martian Gully Formation And Evolution: Studies From The Local To Global Scale, Tanya Nicole Harrison 2016 The University of Western Ontario

Martian Gully Formation And Evolution: Studies From The Local To Global Scale, Tanya Nicole Harrison

Electronic Thesis and Dissertation Repository

Gullies in the mid- and high-latitudes of Mars were first observed in Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images in 1997. Appearing to be geologically young, they quickly became a feature of interest due to the implication of liquid water in their formation based on distinct morphological characteristics including incised channels, many exhibiting features indicative of fluid flow. However, the temperature and pressure conditions on the surface of Mars during its most recent geologic era have not been conducive to sustaining water in the liquid phase for extended periods of time; therefore, a number of “wet” (water-related) and ...


First Major Appearance Of Brachiopod-Dominated Benthic Shelly Communities In The Reef Ecosystem During The Early Silurian, Cale A.C. Gushulak 2016 The University of Western Ontario

First Major Appearance Of Brachiopod-Dominated Benthic Shelly Communities In The Reef Ecosystem During The Early Silurian, Cale A.C. Gushulak

Electronic Thesis and Dissertation Repository

The early Silurian reefs of the Attawapiskat Formation in the Hudson Bay Basin preserved the oldest record of major invasion of the coral-stromatoporoid skeletal reefs by brachiopods and other marine shelly benthos, providing an excellent opportunity for studying the early evolution, functional morphology, and community organization of the rich and diverse reef-dwelling brachiopods. Biometric and multivariate analysis demonstrate that the reef-dwelling Pentameroides septentrionalis evolved from the level-bottom-dwelling Pentameroides subrectus to develop a larger and more globular shell. The reef-dwelling brachiopods in the paleoequatorial Hudson Bay Basin were more diverse than contemporaneous higher latitude reef-dwelling brachiopod faunas, with ten distinct community ...


Isolating Retrograde And Prograde Rayleigh-Wave Modes Using A Polarity Mute, Gabriel Gribler, Lee M. Liberty, T. Dylan Mikesell, Paul Michaels 2016 Boise State University

Isolating Retrograde And Prograde Rayleigh-Wave Modes Using A Polarity Mute, Gabriel Gribler, Lee M. Liberty, T. Dylan Mikesell, Paul Michaels

Dylan Mikesell

Estimates of S-wave velocity with depth from Rayleigh-wave dispersion data are limited by the accuracy of fundamental and/or higher mode signal identification. In many scenarios, the fundamental mode propagates in retrograde motion, whereas higher modes propagate in prograde motion. This difference in particle motion (or polarity) can be used by joint analysis of vertical and horizontal inline recordings. We have developed a novel method that isolates modes by separating prograde and retrograde motions; we call this a polarity mute. Applying this polarity mute prior to traditional multichannel analysis of surface wave (MASW) analysis improves phase velocity estimation for fundamental ...


Trapping Fecal Bacteria And Sediment In Surface Runoff From Cropland Treated With Poultry Litter, Mark S. Coyne, R. A. Gilfillen, Robert L. Blevins 2016 University of Kentucky

Trapping Fecal Bacteria And Sediment In Surface Runoff From Cropland Treated With Poultry Litter, Mark S. Coyne, R. A. Gilfillen, Robert L. Blevins

Mark S. Coyne

Between 1991 and 1994 the broiler population exploded in Kentucky as the poultry industry began to expand. The Kentucky Department of Agriculture predicts that within four years annual broiler production could exceed 275 million birds. This may be good for Kentucky's economy but it carries some important environmental consequences. If expansion continues as anticipated, the estimated waste production from broilers for processing could reach 300,000 tons per year (assuming each broiler house produces 150,000 birds per year and the yearly manure and litter production per house is approximately 160 tons).


The Fecal Coliform/Fecal Streptococci Ratio (Fc/Fs) And Water Quality In The Bluegrass Region Of Kentucky, Mark S. Coyne, J. M. Howell 2016 University of Kentucky

The Fecal Coliform/Fecal Streptococci Ratio (Fc/Fs) And Water Quality In The Bluegrass Region Of Kentucky, Mark S. Coyne, J. M. Howell

Mark S. Coyne

In the mid 70' s, someone noticed that the ratio of two indicator bacteria in fecal wastes - fecal coliforms (FC) and fecal streptococci (FS) - was characteristic of particular animal wastes. In human wastes, the fecal coliform/fecal streptococci ratio (FC/FS ratio) was greater than 4. In domesticated animals, like cattle, the ratio was between 0.1 and 4.0. In wild animals, the ratio was less than 0.1. Since that time, many attempts have been made to use the ratio to determine the source of fecal bacteria in contaminated ground water.


Filter Strip Length And Fecal Bacteria Trapping From Poultry Waste - An Update, Mark S. Coyne, R. A. Gilfillen, Robert L. Blevins 2016 University of Kentucky

Filter Strip Length And Fecal Bacteria Trapping From Poultry Waste - An Update, Mark S. Coyne, R. A. Gilfillen, Robert L. Blevins

Mark S. Coyne

Cheap, efficient, and environmentally sound waste disposal will be needed as Kentucky's broiler industry expands. The filter strip length needed to protect water resources from contaminants in surface runoff is a pressing issue in waste management and water quality. In a previous Soil Science News and Views (Vol. 15, No. 8) we reported that grass filter strips as short as 15 feet can trap over 90% of the fecal bacteria eroding from land-applied and incorporated poultry waste during runoff following rainstorms. In this update, we provide some additional information and conclusions from that study on filter strip length, based ...


Water Quality And Fecal Indicator Bacteria, Mark S. Coyne 2016 University of Kentucky

Water Quality And Fecal Indicator Bacteria, Mark S. Coyne

Mark S. Coyne

How can you tell if water is fit to drink? Color and taste aren't reliable guides for water safety. Clear water can be contaminated with chemicals or microorganisms the senses can't detect. One of the principle qualities of potable (drinkable) water is its freedom from microbial contaminants. This article will describe some criteria and methods that are used to determine the microbial quality of water.


Infiltration Of Fecal Bacteria Through Soils: Timing And Tillage Effects, Mark S. Coyne, C. S. Stoddard, John H. Grove, William O. Thom 2016 University of Kentucky

Infiltration Of Fecal Bacteria Through Soils: Timing And Tillage Effects, Mark S. Coyne, C. S. Stoddard, John H. Grove, William O. Thom

Mark S. Coyne

Land-applying animal wastes potentially exposes humans and animals to fecal pathogens, either by direct contact with soil and produce, or via ground water contamination. Some of these organisms are Salmonella, certain pathogenic Escherichia coli strains, protozoa such as Cryptosporidium and Giardia, and enteric viruses. Whether soil adequately filters these pathogens before they reach ground water depends on the interaction of porosity, texture, depth, water content, rainfall intensity and duration, and soil management.


Agricultural Impacts On Fecal Contamination Of Shallow Groundwaters In The Bluegrass Region Of Kentucky, Mark S. Coyne, J. M. Howell 2016 University of Kentucky

Agricultural Impacts On Fecal Contamination Of Shallow Groundwaters In The Bluegrass Region Of Kentucky, Mark S. Coyne, J. M. Howell

Mark S. Coyne

Any farming practices that degrade water quality contribute to agricultural nonpoint source pollution. This is a problem in Kentucky's Bluegrass region where shallow soils and karst geology permit surface contaminants to reach groundwater quickly. Real and perceived threats to public health may make groundwater protection plans a reality if evidence for non-point source pollution in agricultural areas continues to grow.


Tillage Slows Fecal Bacteria Infiltration Through Soil, Mark S. Coyne, S. W. McMurry, E. Perfect 2016 University of Kentucky

Tillage Slows Fecal Bacteria Infiltration Through Soil, Mark S. Coyne, S. W. Mcmurry, E. Perfect

Mark S. Coyne

Bacterial pathogens can degrade ground water quality by infiltrating and eroding from land treated with poultry wastes. The potential for ground water contamination (as well as associated health risks and cost of water treatment) greatly depends on the depth of soil to the water table or bedrock and soil structure. Pathogens must move through the soil profile to contaminate ground water (although sinkholes can provide a direct channel from the soil surface to the water table in karst areas). Deep soils have less potential for contamination than shallow soils. Structureless soils retain fecal bacteria better than well structured soils. Research ...


Anisotropic Waveform Tomography: Application To Crosshole Data For Transversely Isotropic Media, Shaun Michael Hadden 2016 The University of Western Ontario

Anisotropic Waveform Tomography: Application To Crosshole Data For Transversely Isotropic Media, Shaun Michael Hadden

Electronic Thesis and Dissertation Repository

Anisotropic Traveltime Tomography and Full Waveform Inversion were applied first to synthetic and then to real data following the development of a transversely isotropic model for handling anisotropy. Best-fitting models of seismic velocity and Thomsen's anisotropy parameters were initially obtained from traveltime tomography, and then used as the starting models for Full Waveform Inversion. The use of a Laplace transform approach effectively damps late arriving S-wave artifacts that introduce errors into the modelling process. The results of the synthetic study highlights the tradeoffs in resolution between the two parameter classes, but verify anisotropic traveltime tomography as a valid method ...


Water, Growth And The Endangered Species Act, Holly Doremus 2016 Selected Works

Water, Growth And The Endangered Species Act, Holly Doremus

Holly Doremus

24 pages.


Water, Growth And The Endangered Species Act, Holly Doremus 2016 Selected Works

Water, Growth And The Endangered Species Act, Holly Doremus

Holly Doremus

24 pages.


Tube Coalescence In The Jingfudong Lava Tube And Implications For Lava Flow Hazard Of Tengchong Volcanism, Zhengquan Chen, Yongshun Liu, Haiquan Wei, Jiandong Xu, Wenfeng Guo 2016 Key Laboratory of Active Tectonics and Volcano, Institute of Geology

Tube Coalescence In The Jingfudong Lava Tube And Implications For Lava Flow Hazard Of Tengchong Volcanism, Zhengquan Chen, Yongshun Liu, Haiquan Wei, Jiandong Xu, Wenfeng Guo

International Journal of Speleology

Tube-fed structure occurs as a general phenomenon in Tengchong basic lavas, such as lava tubes, lava plugs and tube-related collapse depressions. We deduced the development of Laoguipo lava flows, which is the longest lava tube (Jingfudong lava tube) evolved in Tengchong volcanic area. Following the detailed documentation of the tube morphology of the Jingfudong lava tube, we propose that the Jingfudong lava tube was formed through vertical coalescence of at least three tubes. The coalescence and bifurcation process are re-constructed by interpretation of tube floor continuity, the distribution of remnant tubes and the scales of lava tube branches (shapes of ...


Determining The Viability Of Recent Storms As Modern Analogues For North-Central Gulf Of Mexico Paleotempestology Through Sedimentary Analysis And Storm Surge Reconstruction, Joshua Caleb Bregy 2016 University of Southern Mississippi

Determining The Viability Of Recent Storms As Modern Analogues For North-Central Gulf Of Mexico Paleotempestology Through Sedimentary Analysis And Storm Surge Reconstruction, Joshua Caleb Bregy

Master's Theses

The northern Gulf of Mexico has been devastated by recent intense storms. Camille (1969) and Katrina (2005) are two notable hurricanes that made landfall in virtually the same location in Mississippi. However, fully understanding the risks and processes associated with hurricane impacts is impeded by a short and fragmented instrumental record. Paleotempestology could potentially use modern analogues from intense storms in this region to extend the hurricane record back to pre-observational time. Existing empirically based models can back-calculate surge heights over coastal systems as a function of transport distance, particle settling velocity, and gravitational acceleration. We collected cores in a ...


Subsidence Monitoring In Hampton Roads Using Satellites, Ben Hamlington 2016 Old Dominion University

Subsidence Monitoring In Hampton Roads Using Satellites, Ben Hamlington

July 29, 2016: The Latest in Sea Level Rise Science

No abstract provided.


Design Of A Conditioner For Smoothing Wind Turbine Output Power, Murali Bottu, Mariesa Crow, A. Curt Elmore 2016 Missouri University of Science and Technology

Design Of A Conditioner For Smoothing Wind Turbine Output Power, Murali Bottu, Mariesa Crow, A. Curt Elmore

Mariesa Crow

As a result of wind speed intermittency, highly variable wind power output can adversely impact local loads. We propose a conditioner to smooth the variable wind power by utilizing the energy of an ultracapacitor. The conditioner is based on a single phase voltage source inverter (VSI) connected between the grid interconnection point and the ultracapacitor. The shunt VSI injects or absorbs active power from the line to smooth the wind power by utilizing the short term storage capabilities of the ultracapacitor. The ultracapacitor is connected to the DC link through a DC-DC converter, which maintains the voltage of the DC ...


Observational Evidence Confirms Modelling Of The Long-Term Integrity Of Co2-Reservoir Caprocks, N. Kampman, A. Busch, P. Bertier, J. Snippe, S. Hangx, V. Pipich, Z. Di, G. Rother, J. F. Harrington, James P. Evans, A. Maskell, H. J. Chapman, M. J. Bickle 2016 Shell Global Solutions International

Observational Evidence Confirms Modelling Of The Long-Term Integrity Of Co2-Reservoir Caprocks, N. Kampman, A. Busch, P. Bertier, J. Snippe, S. Hangx, V. Pipich, Z. Di, G. Rother, J. F. Harrington, James P. Evans, A. Maskell, H. J. Chapman, M. J. Bickle

Geology Faculty Publications

Storage of anthropogenic CO2 in geological formations relies on a caprock as the primary seal preventing buoyant super-critical CO2 escaping. Although natural CO2 reservoirs demonstrate that CO2 may be stored safely for millions of years, uncertainty remains in predicting how caprocks will react with CO2-bearing brines. This uncertainty poses a significant challenge to the risk assessment of geological carbon storage. Here we describe mineral reaction fronts in a CO2 reservoir-caprock system exposed to CO2 over a timescale comparable with that needed for geological carbon storage. The propagation of the reaction front is retarded by ...


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