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2018

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Full-Text Articles in Earth Sciences

Correction To: Organochlorine Chemical Residues In Northern Cardinal (Cardinalis Cardinalis) Eggs From Greater Washington, Dc Usa, Christopher J. Schmitt, Kathy R. Echols, Paul H. Peterman, Carl E. Orazio, K. Christiana Grim, Shirlee Tan, Nora E. Diggs, Peter P. Marra Jul 2018

Correction To: Organochlorine Chemical Residues In Northern Cardinal (Cardinalis Cardinalis) Eggs From Greater Washington, Dc Usa, Christopher J. Schmitt, Kathy R. Echols, Paul H. Peterman, Carl E. Orazio, K. Christiana Grim, Shirlee Tan, Nora E. Diggs, Peter P. Marra

United States Geological Survey: Staff Publications

The original version of this article contained a mistake. Author name in the text citation and reference in section should be Maldonado et al (2016), it was incorrectly spelled as Maldinado et al (2015).


Eleven Years Of Mountain Weather, Snow, Soil Moisture And Streamflow Data From The Rain–Snow Transition Zone – The Johnston Draw Catchment, Reynolds Creek Experimental Watershed And Critical Zone Observatory, Usa, James P. Mcnamara Jul 2018

Eleven Years Of Mountain Weather, Snow, Soil Moisture And Streamflow Data From The Rain–Snow Transition Zone – The Johnston Draw Catchment, Reynolds Creek Experimental Watershed And Critical Zone Observatory, Usa, James P. Mcnamara

Geosciences Faculty Publications and Presentations

Detailed hydrometeorological data from the rain-to-snow transition zone in mountain regions are limited. As the climate warms, the transition from rain to snow is moving to higher elevations, and these changes are altering the timing of downslope water delivery. To understand how these changes impact hydrological and biological processes in this climatologically sensitive region, detailed observations from the rain-to-snow transition zone are required. We present a complete hydrometeorological dataset for water years 2004 through 2014 for a watershed that spans the rain-to-snow transition zone (https://doi.org/10.15482/usda.adc/1402076). The Johnston Draw watershed (1.8km2), ranging from 1497 to 1869m in elevation, is …


Predicting River Stage Using Recurrent Neural Networks, Eric Rohli Jul 2018

Predicting River Stage Using Recurrent Neural Networks, Eric Rohli

LSU Master's Theses

River stage prediction is an important problem in the water transportation industry. Accurate river stage predictions provide crucial information to barge and tow boat operators, port terminal captains, and lock management officials. Shallow river levels caused by prolonged drought impact the loading capacity of barges and tow boats. High river levels caused by excessive rainfall or snowmelt allow for greater tow capacities but make downstream transportation and lock management risky. Current academic river height prediction systems utilize either time series statistical analysis or machine learning algorithms to forecast future river heights, but systems that combine these two areas often limit …


Groundwater And Thermal Legacy Of A Large Paleolake In Taylor Valley, East Antarctica As Evidenced By Airborne Electromagnetic And Sedimentological Techniques, Krista Falcon Myers Jul 2018

Groundwater And Thermal Legacy Of A Large Paleolake In Taylor Valley, East Antarctica As Evidenced By Airborne Electromagnetic And Sedimentological Techniques, Krista Falcon Myers

LSU Master's Theses

During the Last Glacial Maximum, grounded ice in the Ross Sea extended into the otherwise ice-free McMurdo Dry Valleys, creating a series of large ice dammed paleolakes. Grounded ice within the mouth of Taylor Valley allowed for lake levels to reach elevations not possible at modern day and formed what is known as Glacial Lake Washburn (GLW). GLW extended from the eastern portion of Taylor Valley roughly 20 km west to a level ~300 m higher than modern day Lake Fryxell. The formation and existence of GLW has been debated, though previous studies correlate the timing of GLW with early …


Theory And Application Of Geophysical Geodesy For Studying Earth Surface Deformation, Makan A. Karegar Jul 2018

Theory And Application Of Geophysical Geodesy For Studying Earth Surface Deformation, Makan A. Karegar

USF Tampa Graduate Theses and Dissertations

An interdisciplinary approach at the interface between geodesy and geophysics has recently resolved several Earth science problems at regional and global scales. I use the term “geophysical geodesy” to distinguish the technical and theoretical aspect of geodesy from geophysical applications of geodetic techniques. Using a wide range of Earth observation data, I study the spatio-temporal characteristics of Earth surface deformation in the United States associated with several geophysical processes, including natural and anthropogenic subsidence and uplift, regional relative sea-level rise, and continental hydrological loading. The theoretical portion of this dissertation applies loading theory and develops a new hybrid method to …


Distribution Of Classified Soils In South-West Western Australia, Dennis Van Gool, Angela Stuart-Street, Peter Tille Jul 2018

Distribution Of Classified Soils In South-West Western Australia, Dennis Van Gool, Angela Stuart-Street, Peter Tille

Resource management technical reports

This report provides areas, locations and properties of the main soil classifications identified in south-west Western Australia using current conventional soil map data. It is a reference point for classified soils in the south-west. It provides a way of communicating how soil properties or productivity are likely to relate to soils with similar classifications found elsewhere so that soil research or knowledge can be effectively shared around the state and across Australia.

This is a high-level summary of the relationships between the main soil classifications currently used in Western Australia. These are: • Western Australian Soil Groups, WASG (Schoknecht & …


Hydrothermal Water-Rock Reaction Modeling With Microbial Considerations: Rabbit Creek Area, Yellowstone National Park, Wy, Shanna Law Jul 2018

Hydrothermal Water-Rock Reaction Modeling With Microbial Considerations: Rabbit Creek Area, Yellowstone National Park, Wy, Shanna Law

Graduate Theses & Non-Theses

Water-rock reactions at depth are the main control on aqueous hydrothermal chemistries of hot springs and other thermal features. Thermophilic microbes living in the hydrothermal system are a secondary control on aqueous hydrothermal chemistries and are expected to have increasing influence as spring temperatures decrease. The Rabbit Creek area of Yellowstone National Park (YNP) is an ideal case study for investigating the geologic and biologic controls on aqueous hydrothermal chemistries due to the proximity of the drill core Y-5 to geochemically diverse hydrothermal features (17.3⁰C to 92.2⁰C ± 0.1⁰C; field pH values 6.50 to 9.60 ± 0.05).

The modeling program …


The Prairie Post Quarterly Newsletter Of The High Plains Regional Climate Center- July 2018, Natalie Umphlett, Emily Brown, Crystal J. Stiles Jul 2018

The Prairie Post Quarterly Newsletter Of The High Plains Regional Climate Center- July 2018, Natalie Umphlett, Emily Brown, Crystal J. Stiles

Prairie Post: Quarterly Newsletter of the High Plains Regional Climate Center

Inside this issue:

Message from the interim director........................................1

Staff spotlight...........................1

GRAINEX project......................2

Product highlights..................3

Update on regional climate conditions..................................4

GIS Portal....................................4

Regional news..........................5

Recent and upcoming travel and activities.............................6


Hyporheic Source And Sink Of Nitrous Oxide, W. Jeffery Reeder, Annika M. Quick, Tiffany B. Farrell, Shawn G. Benner, Kevin P. Feris, Alessandra Marzadri, Daniele Tonina Jul 2018

Hyporheic Source And Sink Of Nitrous Oxide, W. Jeffery Reeder, Annika M. Quick, Tiffany B. Farrell, Shawn G. Benner, Kevin P. Feris, Alessandra Marzadri, Daniele Tonina

Geosciences Faculty Publications and Presentations

Nitrous oxide (N2O) is a potent greenhouse gas with an estimated 10% of anthropogenic N2O coming from the hyporheic zone of streams and rivers. However, difficulty in making accurate fine-scale field measurements has prevented detailed understanding of the processes of N2O production and emission at the bedform and flowline scales. Using large-scale, replicated flume experiments that employed high-density chemical concentration measurements, we have been able to refine the current conceptualization of N2O production, consumption, and emission from the hyporheic zone. We present a predictive model based on a Damköhler-type transformation (τ̃) in …


Contrasting Governance Learning Processes Of Climate-Leading And -Lagging Cities: Portland, Oregon, And Phoenix, Arizona, Usa, Jonathan H. Fink Jul 2018

Contrasting Governance Learning Processes Of Climate-Leading And -Lagging Cities: Portland, Oregon, And Phoenix, Arizona, Usa, Jonathan H. Fink

Geology Faculty Publications and Presentations

The contrasting histories and political ecologies of two U.S. cities—Portland Oregon and Phoenix Arizona—shed light on their ability to learn from and influence the climate governance of their peers. Portland's populace, political leadership, and business sectors are motivated by environmental and social values, resulting in a collective sense of responsibility for fixing global problems like climate change. The city's pioneering land-use policies, green infrastructure, and multimodal transportation systems solidify its place at the climate action forefront. In contrast, libertarian Phoenix prioritizes real estate, efficient government, tourism, and protection of individual rights—the antithesis of Portland's altruism. However, because Phoenix's economic success …


Droughtscape, Summer 2018, National Drought Mitigation Center Jul 2018

Droughtscape, Summer 2018, National Drought Mitigation Center

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Contents

From the director

Drought expands and intensifies

Dry down fuels fires

Tweeting #drought18

MOISST and NSMN

Caribbean planning progress

Drought observer network study

MENA teams report progress

NDMC global outreach

Climate hub workshop

On the horizon


Characteristics Of Cover-Collapse Sinkholes In Kentucky, James C. Currens Jul 2018

Characteristics Of Cover-Collapse Sinkholes In Kentucky, James C. Currens

Report of Investigations--KGS

Sudden collapse of unconsolidated earth materials over soluble bedrock, known as cover collapse, damages buildings, roads, utility lines, and farm equipment in Kentucky. It has also killed livestock, including Thoroughbred horses, and injured people. The estimated annual cost of sinkhole cover collapse in Kentucky ranges from $20 million to $84 million and is sensitive to rare but expensive events such as the 2014 National Corvette Museum collapse. The Kentucky Geological Survey began developing a catalog of case histories of cover-collapse occurrences in 1997, and receives an average of 24 reports each year. Three hundred fifty-four occurrences of cover-collapse sinkholes throughout …


Isotopic And Geochemical Analysis Of Nitrate Contaminated Groundwater In Edgar, Nebraska, Nathan Roddy Jul 2018

Isotopic And Geochemical Analysis Of Nitrate Contaminated Groundwater In Edgar, Nebraska, Nathan Roddy

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

High nitrate concentrations in the groundwater beneath Edgar, Nebraska have been measured for well over a decade, exceeding the EPA’s MCL of 10 mg-N/L. Investigating the isotopic signature of nitrate and groundwater have determined the likely source(s) of contamination. Apparent seasonal changes exists in nitrate concentration, isotope ratios, and geochemistry, suggesting that sources and flow paths change as a result of irrigation. Samples collected in December and May had very similar nitrate concentrations (average value of 13.7 mg-N/L) and isotopic ratios (δ15N 4.46‰ and δ18O-NO3 20.21‰), suggesting synthetic nitrate fertilizers are the major source of …


Integrated Geophysical Analysis In The Northeastern Gulf Of Mexico, Mei Liu Jul 2018

Integrated Geophysical Analysis In The Northeastern Gulf Of Mexico, Mei Liu

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The formation of the Gulf of Mexico (GoM) relates to the breakup of Pangea and opening of the central Atlantic Ocean. The tectonic history of the basin is still being debated due to lack of geological constraints. This project addresses the crustal architecture in the northeastern GoM from integrative analysis of multiple geophysical datasets to provide constraints for the tectonic reconstruction.

The objectives of this study are: 1) to delineate various tectonic zones (continental and oceanic domains) and map the boundary between them, 2) to derive physical properties of the subsurface rocks, 3) to map the major tectonic structures in …


Assessment Of The Ponderosa Woodlands In Nebraska's Wildcat Hills: Implications For Juniperus Encroachment And Management, Allie Victoria Schiltmeyer Jul 2018

Assessment Of The Ponderosa Woodlands In Nebraska's Wildcat Hills: Implications For Juniperus Encroachment And Management, Allie Victoria Schiltmeyer

School of Natural Resources: Dissertations, Theses, and Student Research

Ponderosa pine (Pinus ponderosa) is a dominant tree species across western North America. Its eastern distribution includes three populations in western Nebraska. This study assesses the distribution, structure and age of ponderosa pine woodlands in one of those regions, the Wildcat Hills. The Wildcat Hills have escaped severe wildfires seen in recent decades in other ponderosa pine regions. Nevertheless, the Wildcat Hills woodlands face multiple threats including climate change, wildfire, drought, pine beetles, and invasive species. Key to these threats is the stand structure of pine woodlands, which have increased in density across much of ponderosa pine’s range. …


Analysis Of Gravity Recovery And Climate Experiment (Grace) Satellite-Derived Data As A Groundwater And Drought Monitoring Tool, Anthony James Mucia Jul 2018

Analysis Of Gravity Recovery And Climate Experiment (Grace) Satellite-Derived Data As A Groundwater And Drought Monitoring Tool, Anthony James Mucia

School of Natural Resources: Dissertations, Theses, and Student Research

This research compares Gravity Recovery and Climate Experiment (GRACE) groundwater storage (GWS) and root zone soil moisture (RZSM) percentiles to measured data, other drought indicators (DIs) and indices, and stakeholder observations for the purpose of assessing the feasibility and usefulness of these products to detect drought conditions. GRACE percentiles were directly compared to historic groundwater percentiles at 89 Nebraska well locations. Spatial time-series correlations over CONUS were performed between GRACE GWS and RZSM and the U.S. Drought Monitor (USDM), Standardized Precipitation Index (SPI), and soil moisture parameters from several North American Land Data Assimilation System (NLDAS) models. A survey of …


Numerical Modeling Of The Effects Of Land Use Change And Irrigation On Streamflow Depletion Of Frenchman Creek, Nebraska, Moussa Guira Jul 2018

Numerical Modeling Of The Effects Of Land Use Change And Irrigation On Streamflow Depletion Of Frenchman Creek, Nebraska, Moussa Guira

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

A three-dimensional Control Volume Finite Difference-based numerical groundwater flow model was constructed to assess the effects of agricultural irrigation and land use change on streamflow depletion. The study area is Frenchman Creek basin located in southwestern corner of the State of Nebraska, USA. This area was subject to an increased proliferation of groundwater abstraction for agricultural purposes since industrial revolution. It has also been subject to land use change from native rangeland to dry and irrigated cropland. The groundwater flow model was spatially discretized using Voronoi cells in unstructured grid built with the USGS MODFLOW-6. Temporal discretization defined 151 time …


Evaluating 21st Century Climate Change For Bolivia: A Comprehensive Dynamical Downscaling Strategy Using The Wrf Regional Climate Model, Azar Mohammad Abadi Jul 2018

Evaluating 21st Century Climate Change For Bolivia: A Comprehensive Dynamical Downscaling Strategy Using The Wrf Regional Climate Model, Azar Mohammad Abadi

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Bolivia is a low-latitude, developing country at grave risk for the effects of human-induced climate changes. This means evaluating the consequences of projected future climate changes is of significant importance. Unfortunately, the complex topography and high elevation of much of the country pose particular challenges, as these effects cannot be suitably resolved at the approximately 100 km spatial resolution of current global climate models (GCM). Therefore, a comprehensive suite of high-resolution climate change simulations was made focused on Bolivia are run using three different GCMs with three different emission scenarios for each to drive the Weather Research and Forecasting (WRF) …


Relationships Between Fluvial Ecosystems And The Iowan Erosion Surface, Lilian Heinzel, Chad E. Heinzel Jul 2018

Relationships Between Fluvial Ecosystems And The Iowan Erosion Surface, Lilian Heinzel, Chad E. Heinzel

Undergraduate Student Work

The streams and rivers of the Iowan Surface partially form the foundation of our local ecosystems, everything from providing drinking water to producing floods. The Black Hawk Creek, Cedar River, and Maquoketa River were studied in the months of June and July of 2018. The goal of the research was to understand the ecology of each water way, how life was sustained by these rivers and creek and how the surrounding landscape may have determined the features of the waterways. Datasheets were filled out describing the sites’ ecological and geologic makeup, and GIS Trimble units were used to chart the …


Advances In Amino Acid Analysis For Marine Related Matrices And Its Application To Coastal Shelf Settings In The Canadian Arctic, Rachel M. Mcmahon Jul 2018

Advances In Amino Acid Analysis For Marine Related Matrices And Its Application To Coastal Shelf Settings In The Canadian Arctic, Rachel M. Mcmahon

OES Theses and Dissertations

Amino acids comprise up to 50% of organic matter in cellular material and are a major fraction of oceanic organic carbon. Amino acids are also considered highly labile during organic matter recycling, making them useful proxies for organic carbon cycling. Nevertheless, analysis of individual amino acids has been burdened by lengthy derivatization and complex analysis since the 1950s. In this thesis, I describe the modification of advanced analytical techniques, developed in the biomedical field, for analysis of marine matrices which allow the determination of at least 40 amino acids without the need for lengthy sample preparation and derivatization, twice the …


Effects Of Substrate Depth And Precipitation Characteristics On Stormwater Retention By Two Green Roofs In Portland Or, Isaac Schultz, David Sailor, Olyssa Starry Jul 2018

Effects Of Substrate Depth And Precipitation Characteristics On Stormwater Retention By Two Green Roofs In Portland Or, Isaac Schultz, David Sailor, Olyssa Starry

University Honors College Faculty Publication and Presentations

Study Region: This study took place in Portland Oregon, a city of over 600,000 residents located in the Willamette Valley in the state of Oregon in the Pacific Northwest region of the United States. Portland experiences a temperate climate with Mediterranean features. Study Focus: Runoff patterns from two extensive green roofs with substrate depths of 75 and 125 mm, situated on a 5000 square meter retail store, were compared over a one year period. Precipitation, irrigation, and storm water discharge were continuously monitored and the performance of the green roofs for storm water control was investigated in detail. New Hydrological …


Beyond Spatial Autocorrelation: A Novel Approach Using Reconstructability Analysis, David Percy, Martin Zwick Jul 2018

Beyond Spatial Autocorrelation: A Novel Approach Using Reconstructability Analysis, David Percy, Martin Zwick

Complex Systems Faculty Publications and Presentations

Raster data are digital representations of spatial phenomena that are organized into rows and columns that typically have the same dimensions in each direction. They are used to represent image data at any scale. Common raster data are medical images, satellite data, and photos generated by modern smartphones.
Satellites capture reflectance data in specific bands of wavelength that correspond to red, green, blue, and often some infrared and thermal bands. These composite vectors can then be classified into actual land use categories such as forest or water using automated techniques. These classifications are verified on the ground using hand-held sensors. …


Examining The Factors Shaping The Population Structure Of Thalassoma Bifasciatum In The Lemon Keys, Guna Yala, Panama, Nicole Stevens Jul 2018

Examining The Factors Shaping The Population Structure Of Thalassoma Bifasciatum In The Lemon Keys, Guna Yala, Panama, Nicole Stevens

Independent Study Project (ISP) Collection

Research question

What is the population structure of Thalassoma bifasciatum in the Lemon Keys, Guna Yala, Panama?

Research objective

To examine size class structure of Thalassoma bifasciatum and how its abundance and density vary in relation to factors such as substrate, species diversity and depth.


Integrated Soil Fertility Management Sequences For Reducing Climate Risk In Smallholder Crop Production Systems In Southern Africa, Hatirarami Nezomba, Florence Mtambanengwe, Jairos Rurinda, Paul Mapfumo Jul 2018

Integrated Soil Fertility Management Sequences For Reducing Climate Risk In Smallholder Crop Production Systems In Southern Africa, Hatirarami Nezomba, Florence Mtambanengwe, Jairos Rurinda, Paul Mapfumo

All Peer-Reviewed Publications

Climate change, increased climate variability and poor soil fertility are major bio-physical constraints to cropping on smallholder farms in southern Africa. We used the Agricultural Production Systems sIMulator (APSIM) to assess maize yield response to integrated soil fertility management (ISFM) rotational sequences of low-quality organic resources, nitrogen-fixing green manure and grain legumes, and mineral fertilizers under baseline (1960–2005) and projected (2040–2069) climates. APSIM was also employed to evaluate the response of maize yield to the ISFM sequences under a combination of a changing climate, and typical sowing dates and mineral fertilizer application rates for smallholder households of varying resource endowment. …


Integrated Geophysical Methods To Characterize Subsidence In Butte, Montana, U.S.A., Kristen Prudhomme Jul 2018

Integrated Geophysical Methods To Characterize Subsidence In Butte, Montana, U.S.A., Kristen Prudhomme

Graduate Theses & Non-Theses

Geophysical investigations, designed to characterize unique subsidence features of unknown natural origin, provide imaging analysis of potential causes of subsidence. Recent subsidence in the alluvial plain in Butte, Montana is unrelated to historic mining in the area. This study aims to utilize a combined application of shallow electrical resistivity tomography (ERT), self-potential (SP), and frequency-domain electromagnetic (FDEM) methods in order to develop a better understanding of the particular set of hydrogeological and environmental conditions that contribute to this unique phenomena. Geophysical measurements provide lateral and vertical variations of electrical resistivity in the subsurface to a depth of 10 m while …


Estimating Live Fuel Moisture In Southern California Using Remote Sensing Vegetation Water Content Proxies, Shenyue Jia, Seung Hee Kim, Son V. Nghiem, Wonhee Cho, Menas Kafatos Jul 2018

Estimating Live Fuel Moisture In Southern California Using Remote Sensing Vegetation Water Content Proxies, Shenyue Jia, Seung Hee Kim, Son V. Nghiem, Wonhee Cho, Menas Kafatos

Mathematics, Physics, and Computer Science Faculty Articles and Research

Wildfires are a major ecological disturbance in Southern California and often lead to great destruction along the Wildland-Urban Interface. Live fuel moisture has been used as an important indicator of wildfire risk in measurements of vegetation water content. However, the limited field measurements of live fuel moisture in both time and space have affected the accuracy of wildfire risk estimations. Traditional estimation of live fuel moisture using remote sensing data was based on vegetation indices, indirect proxies of vegetation water content and subject to influence from weather conditions. In this study, we investigated the feasibility of estimating live fuel moisture …


Shear Wave Tomography Beneath The United States Using A Joint Inversion Of Surface And Body Waves, E. M. Golos, H. Fang, H. Yao, H. Zhang, Scott Burdick, F. Vernon, A. Schaeffer, S. Lebedev, R. D. Van Der Hilst Jun 2018

Shear Wave Tomography Beneath The United States Using A Joint Inversion Of Surface And Body Waves, E. M. Golos, H. Fang, H. Yao, H. Zhang, Scott Burdick, F. Vernon, A. Schaeffer, S. Lebedev, R. D. Van Der Hilst

Environmental Science and Geology Faculty Research Publications

Resolving both crustal and shallow-mantle heterogeneity, which is needed to study processes in and fluxes between crust and mantle, is still a challenge for seismic tomography. Body wave data can constrain deep features but often produce vertical smearing in the crust and upper mantle; in contrast, surface wave data can provide good vertical resolution of lithospheric structure but may lack lateral resolution and are less sensitive to the deeper Earth. These two data types are usually treated and inverted separately, and tomographic models therefore do not, in general, benefit from the complementary nature of sampling by body and surface waves. …


A Broad Spectrum Racemase In Pseudomonas Putida Kt2440 Plays A Key Role In Amino Acid Catabolism, Atanas D. Radkov, Luke A. Moe Jun 2018

A Broad Spectrum Racemase In Pseudomonas Putida Kt2440 Plays A Key Role In Amino Acid Catabolism, Atanas D. Radkov, Luke A. Moe

Plant and Soil Sciences Faculty Publications

The broad-spectrum amino acid racemase (Alr) of Pseudomonas putida KT2440 preferentially interconverts the L- and D-stereoisomers of Lys and Arg. Despite conservation of broad-spectrum racemases among bacteria, little is known regarding their physiological role. Here we explore potential functional roles for Alr in P. putida KT2440. We demonstrate through cellular fractionation that Alr enzymatic activity is found in the periplasm, consistent with its putative periplasm targeting sequence. Specific activity of Alr is highest during exponential growth, and this activity corresponds with an increased accumulation of D-Lys in the growth medium. An alr gene knockout strain (Δalr) was generated …


Magma Mixing At Oldoinyo Lengai: A Mineralogical And Trace Element Analysis Of The 2007-8 Eruption., Nicole Thomas, Tobias P. Fischer Dr., Adrian J. Brearley Dr. Jun 2018

Magma Mixing At Oldoinyo Lengai: A Mineralogical And Trace Element Analysis Of The 2007-8 Eruption., Nicole Thomas, Tobias P. Fischer Dr., Adrian J. Brearley Dr.

Earth and Planetary Sciences ETDs

Chapter I:

The 2007-8 eruption at Lengai was highly explosive, reaching plinian proportions, and the anhydrous nature of the nephelinite magma at Lengai, does not explain this highly volatile behavior. The increase in volatiles in a low H2O nephelinite magma could occur from decompression melting of magma injection from a deeper source. Two distinct nephelinite compositions were identified in a mineralogical analyses of the ash erupta: a highly evolved nephelinite (OL2), with less than 3% glass from the magma chamber, as indicated by the highly peralkalinic feldspathoid: combeite (Na2Ca2Si3O9), commonly found in Lengai eruptive products (Dawson 1966, 1998), and a …


Assessing Bald Cypress (Taxodium Distichum) Tree Dynamic Change In Usf Forest Preserve Area Using Mixture-Tuned Matched Filtering And Multitemporal Satellite Imagery, Yujia Wang Jun 2018

Assessing Bald Cypress (Taxodium Distichum) Tree Dynamic Change In Usf Forest Preserve Area Using Mixture-Tuned Matched Filtering And Multitemporal Satellite Imagery, Yujia Wang

USF Tampa Graduate Theses and Dissertations

Wetlands are the most important and valuable ecosystems on Earth. They are called “kidneys of the Earth”. Vegetation change detection is necessary to understand the condition of a wetland and to support ecosystem sustainable management and utilization. It has been a great challenge to estimate vegetation (including bald cypress trees) coverage of the wetland because it is difficult to access directly. Satellite remote sensing technology can be one important feasible method to map and monitor changes of wetland forest vegetation and land cover over large areas. Remote sensing mapping techniques have been applied to detect and map vegetation changes in …