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One-Dimensional Weakly Nonlinear Model Equations For Rossby Waves, David Henry, Rossen Ivanov 2014 Dublin Institute of Technology

One-Dimensional Weakly Nonlinear Model Equations For Rossby Waves, David Henry, Rossen Ivanov

Articles

In this study we explore several possibilities for modelling weakly nonlinear Rossby waves in fluid of constant depth, which propagate predominantly in one direction. The model equations obtained include the BBM equation, as well as the integrable KdV and Degasperis-Procesi equations.


Speleothems In Cova Des Pas De Vallgornera: Their Distribution And Characteristics Within An Extensive Coastal Cave From The Eogenetic Karst Of Southern Mallorca (Western Mediterranean), Antoni Merino, Joaquín Ginés, Paola Tuccimei, Michele Soligo, Joan Fornós 2014 University of South Florida

Speleothems In Cova Des Pas De Vallgornera: Their Distribution And Characteristics Within An Extensive Coastal Cave From The Eogenetic Karst Of Southern Mallorca (Western Mediterranean), Antoni Merino, Joaquín Ginés, Paola Tuccimei, Michele Soligo, Joan Fornós

International Journal of Speleology

The abundance and variety of speleothems are undoubtedly among the remarkable features of Cova des Pas de Vallgornera, the longest cave system in Mallorca Island developed in the eogenetic karst of its southern coast. Due to the monotonous carbonate lithology of the area, most of the speleothems are composed of calcite and in a few cases aragonite, although other minerals are also represented (e.g., gypsum, celestine, barite.). However, in spite of the rather common mineralogy of the speleothems, its distribution results strongly mediated by the lithologic and textural variability linked to the architecture of the Upper Miocene reefal rocks ...


Microbe-Mineral Relationships And Biogenic Mineral Transformations In Actively Venting Deep-Sea Hydrothermal Sulfide Chimneys, TZIHSUAN J. LIN 2014 SelectedWorks

Microbe-Mineral Relationships And Biogenic Mineral Transformations In Actively Venting Deep-Sea Hydrothermal Sulfide Chimneys, Tzihsuan J. Lin

TZIHSUAN J LIN

This dissertation uses a combination of microbiology, mineralogy, and geochemistry to understand dissimilatory iron reduction in hyperthermophilic archaea and the role and potential impact of these and other vent microorganisms within active deep-sea hydrothermal vent chimneys. The central objective of the dissertation is to determine if mineral composition and chimney type are among the primary determinants of microbial community composition and hyperthermophilic, dissimilatory iron reducer growth, in addition to other environmental factors such as nutrient availability, temperature, pH, and chlorinity. This is done using samples and organisms collected from the Endeavour Segment of the Juan de Fuca Ridge in the ...


Fault And Fluid Interactions In The Elsinore Fault-West Salton Detachment Fault Damage Zones, Agua Caliente County Park, California, Rebekah Erin Wood 2014 Utah State University

Fault And Fluid Interactions In The Elsinore Fault-West Salton Detachment Fault Damage Zones, Agua Caliente County Park, California, Rebekah Erin Wood

All Graduate Theses and Dissertations

This study area provides a unique opportunity to study the intersection of the Elsinore and West Salton detachment faults in southern California, effusing warm springs, and alteration products in the midst of the fault intersection. Structural mapping and compiling previous maps supply an interpretation of the fault zone geometries within the Tierra Blanca Mountains. Geochemical analysis of the crystalline basement and altered protolith help determine the effects of faulting and fluid flow in the study area. In the Tierra Blanca Mountains, the Elsinore strike-slip fault system transitions from the double-stranded Julian segment and Earthquake Valley fault in the northwest, to ...


Data Processing For Oscillatory Pumping Tests, Tania Bakhos, Michael C. Cardiff, Warren Barrash, Peter K. Kitanidis 2014 Boise State University

Data Processing For Oscillatory Pumping Tests, Tania Bakhos, Michael C. Cardiff, Warren Barrash, Peter K. Kitanidis

CGISS Publications and Presentations

Characterizing the subsurface is important for many hydrogeologic projects such as site remediation and groundwater resource exploration. Methods based on the analysis of conventional pumping tests have the notable disadvantage that at a certain distance, the signal is small relative to the noise due to the effects of recharge, pumping in neighboring wells, change in the level or adjacent streams, and other common disturbances. This work focuses on oscillatory pumping tests in which fluid is extracted for half a period, then reinjected. We discuss a major advantage of oscillatory pumping tests: small amplitude signals can be recovered from noisy data ...


The Stardust Interstellar Dust Collector Crater Origins And Hypervelocity Cratering At Oblique Angles In Aluminum Foil, Harison Wiesman 2014 Washington University in St. Louis

The Stardust Interstellar Dust Collector Crater Origins And Hypervelocity Cratering At Oblique Angles In Aluminum Foil, Harison Wiesman

Undergraduate Theses—Unrestricted

From 1999 to 2006 the NASA Stardust mission collected cometary particles from the Wild 2 comet and interstellar dust from the interstellar medium in two collectors made from aerogel tiles and aluminum foil. By studying their isotopic compositions, these particles can provide us with information about nucleosynthetic processes in stars. Both collector trays are being studied for traces of these particles, though a number of challenges have arisen in doing so. Identifying impact craters in the aluminum foil on the interstellar collector tray has been incredibly difficult. In addition to being only a few micrometers or less in diameter, many ...


Survey Of ‘Low-Z’ Particles From The Interplanetary Dust Collection In Search Of Idps, Harison Wiesman 2014 Washington University in St. Louis

Survey Of ‘Low-Z’ Particles From The Interplanetary Dust Collection In Search Of Idps, Harison Wiesman

Undergraduate Theses—Unrestricted

Micrometeorites are one of the most common types of extraterrestrial material that fall to the Earth, beside meteorites and interplanetary dust particles (IDPs). All of these materials are known to contain presolar grains that, when studied in the laboratory, provide information about the origin of the solar system and help to constrain models of nucleosynthesis in stars. Recent studies of micrometeorites revealed the presence of a group of particles with very high C contents. These ultra-carbonaceous Antarctic micrometeorites (UCAMMs) are fine-grained, fluffy particles dominated by highly disordered carbonaceous matter. The presence of H and N isotopic anomalies, abundant presolar grains ...


Effects Of Thinning On Carbon Dynamics In A Temperate Coniferous Forest, Janelle S. Trant 2014 McMaster University

Effects Of Thinning On Carbon Dynamics In A Temperate Coniferous Forest, Janelle S. Trant

Open Access Dissertations and Theses

Forest ecosystems are a significant component of the global carbon (C) cycle. Afforestation is considered a cost-effective and ecologically viable means to sequester atmospheric carbon. However, afforestation requires intensive management practices, including thinning, to maintain and enhance the carbon sequestration capability of the forest. This study examines thinning effects on forest carbon dynamics using eddy covariance (EC) methods. In January 2012, a 74-year-old white pine (Pinus strobus) plantation located in southern Ontario was selectively thinned. Approximately 30% of trees, equating to 2308 m3 of wood (sawlogs and pulpwood), were removed to improve light, water and nutrient availability for remaining ...


Biometric-Based Carbon Estimates And Environmental Controls Within An Age-Sequence Of Temperate Forests, Michelle V. Kula 2014 McMaster University

Biometric-Based Carbon Estimates And Environmental Controls Within An Age-Sequence Of Temperate Forests, Michelle V. Kula

Open Access Dissertations and Theses

Understanding the response of forest carbon uptake and growth to interannual climate variability and forest management practices is important, given the large quantity of carbon stored in forests, and their significant role in the global carbon cycle. Since 2004, biometric and micrometeorological measurements were taken in an age-sequence (10-, 38- and 73-years-old as of 2012) of white pine (Pinus strobes L.) plantation forests in southern Ontario, Canada, providing an 8 year record of carbon sequestration, growth and climate. The 73-year old conifer site was thinned in early 2012, where 25% of trees were removed to improve light and water dynamics ...


Soil Penetromter, David A. Bainbridge 2014 SelectedWorks

Soil Penetromter, David A. Bainbridge

David A Bainbridge

A simple easy to build impact soil penetrometer can provide very useful information on soil strength. This can be very important for restoration planning and management of soils in agriculture and forestry.


Sequential Fragmentation / Transport Theory, Pyroclast Size-Density Relationships, And The Emplacement Dynamics Of Pyroclastic Density Currents – A Case Study On The Mt. St. Helens (Usa) 1980 Eruption, Chelsea Mackaman-Lofland, Brittany D. Brand, Jacopo Taddeucci, Kenneth Wohletz 2014 Boise State University

Sequential Fragmentation / Transport Theory, Pyroclast Size-Density Relationships, And The Emplacement Dynamics Of Pyroclastic Density Currents – A Case Study On The Mt. St. Helens (Usa) 1980 Eruption, Chelsea Mackaman-Lofland, Brittany D. Brand, Jacopo Taddeucci, Kenneth Wohletz

Geosciences Faculty Publications and Presentations

Pyroclastic density currents (PDCs) are the most dangerous hazard associated with explosive volcanic eruptions. Despite recent advancements in the general understanding of PDC dynamics, limited direct observation and/or outcrop scarcity often hinder the interpretation of specific transport and depositional processes at many volcanoes. This study explores the potential of sequential fragmentation / transport theory (SFT; cf. Wohletz et al. 1989), a modeling method capable of predicting particle mass distributions based on the physical principles of fragmentation and transport, to retrieve the transport and depositional dynamics of well-characterized PDCs from the size and density distributions of individual components within the deposits ...


Soil Solarization, David A. Bainbridge 2014 SelectedWorks

Soil Solarization, David A. Bainbridge

David A Bainbridge

Soil solarization makes use of the energy of the sun to heat soil and kill weeds and pathogens. Single, double, or bubblepack plastic and be used to increase soil temperature. Multiple growth benefits are often realized.


Geophysical And Geological Integration And Interpretation Of The Northeast Thelon Basin, Nunavut, Victoria Tschirhart 2014 McMaster University

Geophysical And Geological Integration And Interpretation Of The Northeast Thelon Basin, Nunavut, Victoria Tschirhart

Open Access Dissertations and Theses

The northeast Thelon Basin, Nunavut, is a rapidly developing albeit poorly studied, frontier exploration domain for unconformity-associated uranium deposits. Critical criteria for unconformity –associated uranium deposit models are knowledge of the basement geology, fault history and depth to unconformity surface. This thesis sets forth to derive working geological and geophysical models for the northeast Thelon Basin through the implementation of integrated geophysical techniques.

A physical rock property database is compiled defining average density and susceptibility values for key map units for integration into subsequent modelling iterations. Forward and inverse potential field modelling using these petrophysical with geological controls define the ...


Geology Of The Piedmont Watersheds – Violent Past, Tranquil Present, Walter Cressler 2014 West Chester University

Geology Of The Piedmont Watersheds – Violent Past, Tranquil Present, Walter Cressler

Walt Cressler

No abstract provided.


Improving The Treatment Of Non-Aqueous Phase Tce In Low Permeability Zones With Permanganate, Chanat Chokejaroenrat, Steve D. Comfort, Chainarong Sakulthaew, Bruce Dvoark 2014 University of Nebraska - Lincoln

Improving The Treatment Of Non-Aqueous Phase Tce In Low Permeability Zones With Permanganate, Chanat Chokejaroenrat, Steve D. Comfort, Chainarong Sakulthaew, Bruce Dvoark

Faculty Publications from The Water Center

Treating dense non-aqueous phase liquids (DNAPLs) embedded in low permeability zones (LPZs) is aparticularly challenging issue for injection-based remedial treatments. Our objective was to improve thesweeping efficiency of permanganate (MnO4−) into LPZs to treat high concentrations of TCE. This wasaccomplished by conducting transport experiments that quantified the penetration of various perman-ganate flooding solutions into a LPZ that was spiked with non-aqueous phase14C-TCE. The treatments weevaluated included permanganate paired with: (i) a shear-thinning polymer (xanthan); (ii) stabilizationaids that minimized MnO2rind formation and (iii) a phase-transfer catalyst. In addition, we quantifiedthe ability of these flooding solutions to improve TCE destruction under batch ...


Geologic Constraints And Speleogenesis Of Cova Des Pas De Vallgornera, A Complex Coastal Cave From Mallorca Island (Western Mediterranean), Joaquín Ginés, Joan J. Fornós, Angel Ginés, Antoni Merino, Francesc Gràcia 2014 University of South Florida

Geologic Constraints And Speleogenesis Of Cova Des Pas De Vallgornera, A Complex Coastal Cave From Mallorca Island (Western Mediterranean), Joaquín Ginés, Joan J. Fornós, Angel Ginés, Antoni Merino, Francesc Gràcia

International Journal of Speleology

The flat areas of eastern and southern Mallorca host a remarkable coastal karst, where Cova des Pas de Vallgornera stands out due to its length (more than 74 km) and its special morphological suite. The pattern of the cave is quite heterogeneous showing sharp differences produced by the architecture of the Upper Miocene reef: spongework mazes and collapse chambers dominate in the reef front facies, whereas joint-guided conduits are the rule in the back reef carbonates. Regarding the speleogenesis of the system, a complex situation is envisaged involving three main agents: coastal mixing dissolution, drainage of meteoric diffuse recharge, and ...


Spring Tillage Pitfalls, Mahdi Al-Kaisi 2014 Iowa State University

Spring Tillage Pitfalls, Mahdi Al-Kaisi

Integrated Crop Management News

Generally, springtime is not an ideal time for conducting tillage because of potential negative soil and agronomic outcomes associated with tillage in wet conditions. These soil and agronomic problems are linked together in affecting yield. Here are some of the reasons to avoid spring tillage.


National Cave And Karst Research Institute Special Paper 2: Role Of Hydrogen Sulfide In The Formation Of Cave And Karst Phenomena In The Guadalupe Mountains And Western Delaware Basin, New Mexico And Texas, Douglas W. Kirkland 2014 University of South Florida

National Cave And Karst Research Institute Special Paper 2: Role Of Hydrogen Sulfide In The Formation Of Cave And Karst Phenomena In The Guadalupe Mountains And Western Delaware Basin, New Mexico And Texas, Douglas W. Kirkland

Environmental Sustainability Books

The National Cave and Karst Research Institute is pleased to publish Dr. Doug Kirkland’s monograph on the role of hydrogen sulfide on speleogenesis in the Guadalupe Mountains and western Delaware Basin. Dr. Kirkland’s work builds on his many years of research in southeastern New Mexico and west Texas, and provides the most comprehensive overview of cave and karst phenomena in the greater Delaware Basin region in almost 20 years. His work incorporates and summarizes decades of research by previous workers, combined with new ideas he has developed on speleogenesis in the Guadalupe Mountains. We feel confident that this ...


Similar Resilience Attributes In Lakes With Different Management Practices, Didier L. Baho, Stina Drakare, Richard K. Johnson, Craig R. Allen, David G. Angeler 2014 University of Nebraska - Lincoln

Similar Resilience Attributes In Lakes With Different Management Practices, Didier L. Baho, Stina Drakare, Richard K. Johnson, Craig R. Allen, David G. Angeler

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

Liming has been used extensively in Scandinavia and elsewhere since the 1970s to counteract the negative effects of acidification. Communities in limed lakes usually return to acidified conditions once liming is discontinued, suggesting that liming is unlikely to shift acidified lakes to a state equivalent to pre-acidification conditions that requires no further management intervention. While this suggests a low resilience of limed lakes, attributes that confer resilience have not been assessed, limiting our understanding of the efficiency of costly management programs. In this study, we assessed community metrics (diversity, richness, evenness, biovolume), multivariate community structure and the relative resilience of ...


Influence Of Introgression And Geological Processes On Phylogenetic Relationships Of Western North American Mountain Suckers (Pantosteus, Catostomidae), Peter J. Unmack, Thomas E. Dowling, Nina J. Laitinen, Carol L. Secor, Richard L. Mayden, Dennis K. Shiozawa, Gerald R. Smith 2014 Wayne State University

Influence Of Introgression And Geological Processes On Phylogenetic Relationships Of Western North American Mountain Suckers (Pantosteus, Catostomidae), Peter J. Unmack, Thomas E. Dowling, Nina J. Laitinen, Carol L. Secor, Richard L. Mayden, Dennis K. Shiozawa, Gerald R. Smith

Biological Sciences Faculty Research Publications

Intense geological activity caused major topographic changes in Western North America over the past 15 million years. Major rivers here are composites of different ancient rivers, resulting in isolation and mixing episodes between river basins over time. This history influenced the diversification of most of the aquatic fauna. The genus Pantosteus is one of several clades centered in this tectonically active region. The eight recognized Pantosteus species are widespread and common across southwestern Canada, western USA and into northern Mexico. They are typically found in medium gradient, middle-elevation reaches of rivers over rocky substrates. This study (1) compares molecular data ...


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