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Earth Sciences

University of Kentucky

Series

2021

Articles 1 - 15 of 15

Full-Text Articles in Physical Sciences and Mathematics

Removal Of The Northern Paleo-Teton Range Along The Yellowstone Hotspot Track, J. Ryan Thigpen, Summer J. Brown, Autumn L. Helfrich, Rachel Hoar, Michael M. Mcglue, Edward W. Woolery, William R. Guenthner, Meredith L. Swallom, Spencer Dixon, Sean Gallen Oct 2021

Removal Of The Northern Paleo-Teton Range Along The Yellowstone Hotspot Track, J. Ryan Thigpen, Summer J. Brown, Autumn L. Helfrich, Rachel Hoar, Michael M. Mcglue, Edward W. Woolery, William R. Guenthner, Meredith L. Swallom, Spencer Dixon, Sean Gallen

Earth and Environmental Sciences Faculty Publications

Classically held mechanisms for removing mountain topography (e.g., erosion and gravitational collapse) require 10-100 Myr or more to completely remove tectonically generated relief. Here, we propose that mountain ranges can be completely and rapidly (< 2 Myr) removed by a migrating hotspot. In western North America, multiple mountain ranges, including the Teton Range, terminate at the boundary with the relatively low relief track of the Yellowstone hotspot. This abrupt transition leads to a previously untested hypothesis that preexisting mountainous topography along the track has been erased. We integrate thermochronologic data collected from the footwall of the Teton fault with flexural-kinematic modeling and length-displacement scaling to show that the paleo-Teton fault and associated Teton Range was much longer (min. original length 190-210 km) than the present topographic expression of the range front (~65 km) and extended across the modern-day Yellowstone hotspot track. These analyses also indicate that the majority of fault displacement (min. 11.4-12.6 km) and the associated footwall mountain range growth had accumulated prior to Yellowstone encroachment at ~2 Ma, leading us to interpret that eastward migration of the Yellowstone hotspot relative to stable North America led to removal of the paleo-Teton mountain topography via posteruptive collapse of the range following multiple supercaldera (VEI 8) eruptions from 2.0 Ma to 600 ka and/or an isostatic collapse response, similar to ranges north of the Snake River plain. While this extremely rapid removal of mountain ranges and adjoining basins is probably relatively infrequent in the geologic record, it has important implications for continental physiography and topography over very short time spans.

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Elastic Thickness And Crust-Mantle Interface Models Of Tharsis Bulge On Mars And Surrounding Areas, R. T. Ratheesh-Kumar, Dhananjay Ravat, Paul Morgan Oct 2021

Elastic Thickness And Crust-Mantle Interface Models Of Tharsis Bulge On Mars And Surrounding Areas, R. T. Ratheesh-Kumar, Dhananjay Ravat, Paul Morgan

Earth and Environmental Sciences Research Data

The datasets contain the final models of spatial variation of elastic thickness (Te) and the depth to Moho or the Crust-Mantle Interface (CMI) of the Tharsis Bulge and the surrounding regions derived from the software package LithoFLEX. The models are based on the crustal density of 2900 kg/m3, which was selected from analyzing results of a range of densities, and other standard lithospheric parameters. The models are useful for understanding the nature and evolution of the Tharsis Bulge and the surrounding regions.

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Legacy Effects Of Intercropping And Nitrogen Fertilization On Soil N Cycling, Nitrous Oxide Emissions, And The Soil Microbial Community In Tropical Maize Production, Lucas P. Canisares, Hanna J. Poffenbarger, Eoin L. Brodie, Patrick O. Sorensen, Ulas Karaoz, Daniel M. Villegas, Jacobo Arango, Letusa Momesso, Carlos Alexandre Costa Crusciol, Heitor Cantarella Oct 2021

Legacy Effects Of Intercropping And Nitrogen Fertilization On Soil N Cycling, Nitrous Oxide Emissions, And The Soil Microbial Community In Tropical Maize Production, Lucas P. Canisares, Hanna J. Poffenbarger, Eoin L. Brodie, Patrick O. Sorensen, Ulas Karaoz, Daniel M. Villegas, Jacobo Arango, Letusa Momesso, Carlos Alexandre Costa Crusciol, Heitor Cantarella

Plant and Soil Sciences Faculty Publications

Maize-forage grasses intercropping systems have been increasingly adopted by farmers because of their capacity to recycle nutrients, provide mulch, and add C to soil. However, grasses have been shown to increase nitrous oxide (N2O) emissions. Some tropical grasses cause biological nitrification inhibition (BNI) which could mitigate N2O emissions in the maize cycle but the reactions of the N cycle and the microbial changes that explain the N2O emissions are little known in such intercropping systems. With this in mind, we explored intercropping of forage grasses (Brachiaria brizantha and Brachiaria humidicola) with distinct …

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Farmer Perceptions Of Adopting Novel Legumes In Traditional Maize-Based Farming Systems In The Yucatan Peninsula, Jacques Fils Pierre, Luis Latournerie-Moreno, René Garruña-Hernández, Krista L. Jacobsen, Carrie A. M. Laboski, Lucila De Lourdes Salazar-Barrientos, Esaú Ruiz-Sánchez Oct 2021

Farmer Perceptions Of Adopting Novel Legumes In Traditional Maize-Based Farming Systems In The Yucatan Peninsula, Jacques Fils Pierre, Luis Latournerie-Moreno, René Garruña-Hernández, Krista L. Jacobsen, Carrie A. M. Laboski, Lucila De Lourdes Salazar-Barrientos, Esaú Ruiz-Sánchez

Horticulture Faculty Publications

Intercropping constitutes the traditional farming system practice used in various forms for maize production in the Yucatan peninsula. Although practiced for centuries, problems persist with competition for water, nutrients and light between crop species in traditional farming systems. Furthermore, little is known about farmers’ perceptions regarding changes to traditional maize-legume intercropping systems and their interest in novel crop adoption to increase yields in the system while maintaining the practice. The objective of this study was to investigate the maize-based traditional cropping system by assessing the underlying motives and concepts of farmers to practice intercropping in the Yucatan Peninsula and to …

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Tectonic Transport Directions, Shear Senses And Deformation Temperatures Indicated By Quartz C-Axis Fabrics And Microstructures In A Nw-Se Transect Across The Moine And Sgurr Beag Thrust Sheets, Caledonian Orogen Of Northern Scotland, Richard D. Law, J. Ryan Thigpen, Sarah E. Mazza, Calvin A. Mako, Maarten Krabbendam, Brandon M. Spencer, Kyle T. Ashley, Robin A. Strachan, Ella F. Davis Sep 2021

Tectonic Transport Directions, Shear Senses And Deformation Temperatures Indicated By Quartz C-Axis Fabrics And Microstructures In A Nw-Se Transect Across The Moine And Sgurr Beag Thrust Sheets, Caledonian Orogen Of Northern Scotland, Richard D. Law, J. Ryan Thigpen, Sarah E. Mazza, Calvin A. Mako, Maarten Krabbendam, Brandon M. Spencer, Kyle T. Ashley, Robin A. Strachan, Ella F. Davis

Earth and Environmental Sciences Faculty Publications

Moine metasedimentary rocks of northern Scotland are characterized by arcuate map patterns of mineral lineations that swing progressively clockwise from orogen-perpendicular E-trending lineations in greenschist facies mylonites above the Moine thrust on the foreland edge of the Caledonian Orogen, to S-trending lineations at higher structural levels and metamorphic grades in the hinterland. Quartz c-axis fabrics measured on a west to east coast transect demonstrate that the lineations developed parallel to the maximum principal extension direction and therefore track the local tectonic transport direction. Microstructures and c-axis fabrics document a progressive change from top to the N shearing in the hinterland …

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Analysis Of Rock Varnish From The Mojave Desert By Handheld Laser-Induced Breakdown Spectroscopy, Russell S. Harmon, Daria Khashchevskaya, Michelle Morency, Lewis A. Owen, Morgan Jennings, Jeffrey R. Knott, Jason M. Dortch Aug 2021

Analysis Of Rock Varnish From The Mojave Desert By Handheld Laser-Induced Breakdown Spectroscopy, Russell S. Harmon, Daria Khashchevskaya, Michelle Morency, Lewis A. Owen, Morgan Jennings, Jeffrey R. Knott, Jason M. Dortch

Faculty, Staff, and Affiliated Publications--KGS

Laser-induced breakdown spectroscopy (LIBS) is a form of optical emission spectroscopy that can be used for the rapid analysis of geological materials in the field under ambient environmental conditions. We describe here the innovative use of handheld LIBS for the in situ analysis of rock varnish. This thinly laminated and compositionally complex veneer forms slowly over time on rock surfaces in dryland regions and is particularly abundant across the Mojave Desert climatic region of east-central California (USA). Following the depth profiling examination of a varnished clast from colluvial gravel in Death Valley in the laboratory, our in situ analysis of …

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Impact Of Nitrogen Rate In Conventional And Organic Production Systems On Yield And Bread Baking Quality Of Soft Red Winter Wheat, Ammar Al-Zubade, Timothy D. Phillips, Mark A. Williams, Krista L. Jacobsen, David Van Sanford Aug 2021

Impact Of Nitrogen Rate In Conventional And Organic Production Systems On Yield And Bread Baking Quality Of Soft Red Winter Wheat, Ammar Al-Zubade, Timothy D. Phillips, Mark A. Williams, Krista L. Jacobsen, David Van Sanford

Plant and Soil Sciences Faculty Publications

Soft red winter wheat (SRW) is characterized by high yield and relatively low protein content. In Kentucky, there is growing demand from local artisan bread bakers for regionally produced flour, requiring production of grain with increased protein content and/or strength. The objective of this two-year field experiment was to evaluate the effect of nitrogen (N) management on five cultivars of winter wheat on yield and bread baking quality traits of modern and landrace SRW cultivars (Triticum aestivum L.). All five cultivars were evaluated using two N application rates in conventional and organic production systems. All traits measured were significantly …

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Nitrogen And Rainfall Effects On Crop Growth—Experimental Results And Scenario Analyses, Saadi Sattar Shahadha, Ole O. Wendroth, Dianyuan Ding Aug 2021

Nitrogen And Rainfall Effects On Crop Growth—Experimental Results And Scenario Analyses, Saadi Sattar Shahadha, Ole O. Wendroth, Dianyuan Ding

Plant and Soil Sciences Faculty Publications

Nitrogen (N) fertilization is critical for crop growth; however, its effect on crop growth and evapotranspiration (ETc) behaviors under different amounts of rainfall is not well understood. As such, there is a need for studying the impact of nitrogen application rates and rainfall amounts on crop growth and ETc components. Agricultural system models help to fill this knowledge gap, e.g., the Root Zone Water Quality Model (RZWQM2), which integrates crop growth-related processes. The objective of this study is to investigate the effect of the nitrogen application rate on crop growth, soil water dynamics, and ETc behavior under different rainfall amounts …

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Migmatite-Like Textures In Anthracite: Further Evidence For Low-Grade Metamorphic Melting And Resolidification In High-Rank Coals, James C. Hower, Susan M. Rimmer, Maria Mastalerz, Nicola J. Wagner May 2021

Migmatite-Like Textures In Anthracite: Further Evidence For Low-Grade Metamorphic Melting And Resolidification In High-Rank Coals, James C. Hower, Susan M. Rimmer, Maria Mastalerz, Nicola J. Wagner

Center for Applied Energy Research Faculty and Staff Publications

Previous studies demonstrated that melting, initiated by supercritical fluids in the 375–400 °C range, occurred as part of anthracite metamorphism in the Appalachian Basin. Based on the known behavior of vitrinite at high temperatures and, to a lesser extent, at high pressures, it was determined that the duration of the heating, melting, and resolidification event was about 1 h. In the current study, featureless vitrinite within banded maceral assemblages demonstrates the intimate association of melted and resolidified vitrinite with anthracite-rank macerals. By analogy with metamorphosed inorganic rocks, such associations represent diadysites and embrechites, i.e., cross-cutting and layered migmatites, respectively. Even …

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Possibilities Of Using Silicate Rock Powder: An Overview, Claudete Gindri Ramos, James C. Hower, Erika Blanco, Marcos Leandro Silva Oliveira, Suzi Huff Theodoro Mar 2021

Possibilities Of Using Silicate Rock Powder: An Overview, Claudete Gindri Ramos, James C. Hower, Erika Blanco, Marcos Leandro Silva Oliveira, Suzi Huff Theodoro

Center for Applied Energy Research Faculty and Staff Publications

This study evaluates the on use of crushed rocks (remineralizers) to increase soil fertility levels and which contributed to increase agricultural productivity, recovery of degraded areas, decontamination of water, and carbon sequestration. The use of these geological materials is part of the assumptions of rock technology and, indirectly, facilitates the achievement of sustainable development goals related to soil management, climate change, and the preservation of water resources. Research over the past 50 years on silicate rocks focused on soil fertility management and agricultural productivity. More recently, the combined use with microorganisms and organic correctives have shown positive results to mitigate …

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Climate, Vegetation, And Weathering Across Space And Time In Lake Tanganyika (Tropical Eastern Africa), Sarah J. Ivory, Michael M. Mcglue, Cara Peterman, Patrick Baldwin, Joseph Lucas, Andrew Cohen, James Russell, Justina Saroni, Emma Msaky, Ishmael Kimirei, Michael Soreghan Feb 2021

Climate, Vegetation, And Weathering Across Space And Time In Lake Tanganyika (Tropical Eastern Africa), Sarah J. Ivory, Michael M. Mcglue, Cara Peterman, Patrick Baldwin, Joseph Lucas, Andrew Cohen, James Russell, Justina Saroni, Emma Msaky, Ishmael Kimirei, Michael Soreghan

Earth and Environmental Sciences Faculty Publications

Climate and vegetation influence weathering rates and processes; however, evaluating the effects of each and feedbacks between systems, has yet to be accomplished for many types of landscapes. A detailed understanding of how these processes interact to shape landscapes is particularly crucial for reconciling future scenarios of changing climate, where profound alterations to both the biosphere and geosphere are anticipated. In the tropics, ecosystem services, such as soil and water quality, are linked to both vegetation and weathering processes that form a strong control on natural resources that are the foundation of many communities’ daily subsistence. This understanding is further …

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Artisanal Ceramic Factories Using Wood Combustion: A Nanoparticles And Human Health Study, Kátia Martinello, James C. Hower, Diana Pinto, Carlos E. Schnorr, Guilherme L. Dotto, Marcos Leandro Silva Oliveira, Claudete Gindri Ramos Jan 2021

Artisanal Ceramic Factories Using Wood Combustion: A Nanoparticles And Human Health Study, Kátia Martinello, James C. Hower, Diana Pinto, Carlos E. Schnorr, Guilherme L. Dotto, Marcos Leandro Silva Oliveira, Claudete Gindri Ramos

Earth and Environmental Sciences Faculty Publications

The ceramics industry, resulting from developments of modern compounds, is a segment of great influence in worldwide sustainability. Artisanal ceramic factories based on wood combustion have significant risks for the creation and discharge of atmosphere nanoparticles (NPs) and ultra-fine particles (UFPs). At present, there is insufficient recognition on the influence of engineered-NPs on the atmosphere and health. Real improvements are indispensable to diminish contact with NPs. The present study demonstrates the main NPs and UFPS present in an area of intense artisanal wood-combustion ceramic manufacturing. Particulate matter was sampled for morphological, chemical, and geochemical studies by sophisticated electron microbeam microscopy, …

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The History Of The International Grassland Congress 1927-2020, S. Ray Smith, Vivien G. Allen, Roger Wilkins, Garry D. Lacefield Jan 2021

The History Of The International Grassland Congress 1927-2020, S. Ray Smith, Vivien G. Allen, Roger Wilkins, Garry D. Lacefield

Plant and Soil Sciences Presentations

Grasslands cover 27% of the world’s land area and 70% of agricultural land. They form an important foundation for agriculture and livestock husbandry and contribute to the livelihoods of more than 800 million people. The International Grassland Congress (IGC) began as a meeting of a small group of forage researchers in Europe in 1927. It has now expanded into a gathering held every 3-5 years with over 1000 delegates from 80+ countries who represent research, extension, and primary production. The newly released IGC history provides not only an overview of the IGC Congress over the last 93 years, but highlights …

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Wine Terroir And The Soil Bacteria: An Amplicon Sequencing-Based Assessment Of The Barossa Valley And Its Sub-Regions, Jia Zhou, Timothy R. Cavagnaro, Roberta De Bei, Tiffanie M. Nelson, John R. Stephen, Andrew Metcalfe, Matthew Gilliham, James Breen, Cassandra Collins, Carlos M. Rodríguez López Jan 2021

Wine Terroir And The Soil Bacteria: An Amplicon Sequencing-Based Assessment Of The Barossa Valley And Its Sub-Regions, Jia Zhou, Timothy R. Cavagnaro, Roberta De Bei, Tiffanie M. Nelson, John R. Stephen, Andrew Metcalfe, Matthew Gilliham, James Breen, Cassandra Collins, Carlos M. Rodríguez López

Horticulture Faculty Publications

A wines’ terroir, represented as wine traits with regional distinctiveness, is a reflection of both the biophysical and human-driven conditions in which the grapes were grown and wine made. Soil is an important factor contributing to the uniqueness of a wine produced by vines grown in specific conditions. Here, we evaluated the impact of environmental variables on the soil bacteria of 22 Barossa Valley vineyard sites based on the 16S rRNA gene hypervariable region 4. In this study, we report that both dispersal isolation by geographic distance and environmental heterogeneity (soil plant-available P content, elevation, rainfall, temperature, spacing between row …

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Deposition Of Nanoparticles On School Eyeglasses In Urban And Rural Areas: A Methodology For A More Real Assessment Of The Possible Impacts, Ḱtia Martinello, James C. Hower, Guilherme L. Dotto, Claudete Gindri Ramos, Carlos E. Schnorr, Diana Pinto Jan 2021

Deposition Of Nanoparticles On School Eyeglasses In Urban And Rural Areas: A Methodology For A More Real Assessment Of The Possible Impacts, Ḱtia Martinello, James C. Hower, Guilherme L. Dotto, Claudete Gindri Ramos, Carlos E. Schnorr, Diana Pinto

Earth and Environmental Sciences Faculty Publications

Because incomplete confirmation is available concerning the influential role of atmosphere contamination on conjunctivitis, myopia, asthma, and allergic rhinitis in Brazil, the focus of the present work is to explore the possible relations among atmosphere contamination and eye problems. Rather that a case study on eye diseases, by way of questionnaires supplemented by the investigation of nanoparticles (NPs) on eyeglasses, the study examines the mechanisms in which NPs and ultra-fine particles are deposited on the glasses of children up to 10 years of age in urban and rural area. The important connection between atmosphere contaminants and individual protection equipment justifies …

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