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Extreme Differentiation Along Multiple Liquid Lines Of Descent In Strongly Peralkaline Magma Series At Pantelleria (Italy), John C. White, Ray Macdonald, Bogusław Bagiński, Katarzyna M. Liszewska Feb 2023

Extreme Differentiation Along Multiple Liquid Lines Of Descent In Strongly Peralkaline Magma Series At Pantelleria (Italy), John C. White, Ray Macdonald, Bogusław Bagiński, Katarzyna M. Liszewska

EKU Faculty and Staff Scholarship

The liquid line of descent from trachyte to pantellerite is controlled primarily by fractional crystallization of alkali feldspar, with whole rock compositions following a fractionation path along the ‘thermal valley’ in the peralkaline haplogranite system Qz-Ab-Or-Ac-Ns and terminating at a minimum on the feldspar-quartz cotectic. Although whole-rock compositions for different pantelleritic suites follow nearly identical paths in a Qz-Ab-Or projection that terminate near the experimental minimum (Qz40.5Or34.5Ab25 at 100 MPa, projected from Ac-Ns), matrix glass from samples with near-minimum compositions record extreme differentiation and form a ‘cotectic delta’ beyond the terminus of the ‘thermal valley’. Although each glass trend shows …


City Of Tampa Tree Canopy And Urban Forest Analysis 2021, Shawn M. Landry, Andrew K. Koeser, Rebecca Zarger, Kira Rib, Allyson Salisbury, Robert J. Northrop, Michael G. Andreu, Allison Bednar, Zach Freeman Feb 2023

City Of Tampa Tree Canopy And Urban Forest Analysis 2021, Shawn M. Landry, Andrew K. Koeser, Rebecca Zarger, Kira Rib, Allyson Salisbury, Robert J. Northrop, Michael G. Andreu, Allison Bednar, Zach Freeman

School of Geosciences Faculty and Staff Publications

This report summarizes the fourth tree canopy and urban forest analysis conducted for the City of Tampa and represents the year 2021. The City of Tampa tree ordinance (Ord. No. 2006-74, § 9, 3-23-06) requires an assessment of the tree canopy and urban forest every five years (beginning in 20061). In an effort to reduce concerns over bias, this work has been conducted by a collaborative team from the University of South Florida and the University of Florida following established USDA Forest Service protocols.

This report provides detailed information about the current size, composition, health, and distribution of Tampa’s urban …


Grassland Productivity And Water Quality: A 21st Century Issue, David M. Nash, P. M. Haygarth Jan 2023

Grassland Productivity And Water Quality: A 21st Century Issue, David M. Nash, P. M. Haygarth

IGC Proceedings (1977-2023)

  1. Irrigation and other changes to the hydrological cycle can increase soil and water salinity.
  2. Primary salinisation is a natural process that affects much of Europe, Asia, Africa, the Americas and Australia. Secondary salinisation is caused by human activities such as irrigation and land clearing that mobilise salt stored in the soil.
  3. The critical water contaminants exported from grasslands are nitrogen, phosphorus, potential pathogens and sediment.
  4. The mechanisms responsible for diffuse pollution from grasslands and mitigation strategies are most effectively investigated using a ‘source-mobilisation-transport’ framework.
  5. There is a lack of coherent interaction across discipline boundaries that links pollutant sources to impact. …


Water Resources, Agriculture And Pasture: Implications Of Growing Demand And Increasing Scarcity, M. W. Rosegrant, R. A. Valmonte-Santos, S. A. Cline, C. Ringler, W. Li Jan 2023

Water Resources, Agriculture And Pasture: Implications Of Growing Demand And Increasing Scarcity, M. W. Rosegrant, R. A. Valmonte-Santos, S. A. Cline, C. Ringler, W. Li

IGC Proceedings (1977-2023)

  1. Water availability for irrigation is threatened in many regions by rapidly increasing demand for nonagricultural water uses in industry, households, and the environment. The scarcity of irrigation water will not only impact crop production, but also meat production, as much of the pasture used to feed livestock is irrigated.
  2. Grassland is caught between two countervailing forces: a requirement for increasing meat demand that boosts the need for additional pasture to support livestock production, and rapidly increasing water scarcity that makes pasture irrigation uneconomical.
  3. The most effective means of dealing with water scarcity is likely to be conserving water in existing …


Soil Quality Assessment And Management, M. G. Kibblewhite Jan 2023

Soil Quality Assessment And Management, M. G. Kibblewhite

IGC Proceedings (1977-2023)

  1. Soil quality is related to the capacity of soil to deliver ecosystem services on a sustainable basis.
  2. Effective management of soil within grasslands can deliver many benefits to mankind but poor management may cause loss of soil quality from erosion, loss of organic matter, physical deterioration etc.
  3. Services are delivered from soil by biological processes. Soil quality depends on the form and condition of the soil habitat. Fixed factors (e.g. texture) are useful for assigning soil to types. Variable factors (e.g. organic carbon) can then be used to assess quality within soil types, by reference to percentiles of the distribution …


Soil Microbial Community: Understanding The Belowground Network For Sustainable Grassland Management, Y. G. Zhu, W. D. Kong, B. D. Chen, Z. B. Nan, P. Christie Jan 2023

Soil Microbial Community: Understanding The Belowground Network For Sustainable Grassland Management, Y. G. Zhu, W. D. Kong, B. D. Chen, Z. B. Nan, P. Christie

IGC Proceedings (1977-2023)

  1. In addition to the use of conventional methodologies in soil microbial research, molecular techniques are now being applied to gain insights into the soil microbial community;
  2. Plant diversity can exert impacts on soil microbial diversity (through root activities and plant litter etc.), but may in itself be significantly altered by soil properties;
  3. Soil microbial diversity largely determines the stability of soil ecosystems under biotic and abiotic perturbations.
  4. Management of soil microbial diversity can only be achieved through better understanding their structures and functions.


Grasslands1 For Production And The Environment, David R. Kemp, David L. Michalk Jan 2023

Grasslands1 For Production And The Environment, David R. Kemp, David L. Michalk

IGC Proceedings (1977-2023)

  1. To manage grasslands for production and enhanced environmental values requires a redefinition of the frameworks within which management decisions are made, and a tailoring of practices to suit the ways that farmers operate.
  2. Improving the perenniality and permanence of grasslands usually leads to better environmental and production outcomes.
  3. There is a case for a more conservative approach to utilising grasslands in order to sustain the functioning of local ecosystems and to improve water quality, nutrient and energy cycling and biodiversity.
  4. A landscape rather than paddock focus is more appropriate for meeting current grassland management objectives. Grasslands can be triaged to …


The Potential Of Grassland And Associated Forages To Produce Fibre, Biomass, Energy Or Other Feedstocks For Non-Food And Other Sectors: New Uses For A Global Resource, M. F. Askew Jan 2023

The Potential Of Grassland And Associated Forages To Produce Fibre, Biomass, Energy Or Other Feedstocks For Non-Food And Other Sectors: New Uses For A Global Resource, M. F. Askew

IGC Proceedings (1977-2023)

  1. In developed countries increased areas of land will become available for non-food production. Recent reforms of the Common Agricultural Policy will further intensify this trend in Europe.
  2. There is potential for grassland and associated species to contribute to large tonnage markets of energy and bulk fibres, to the supply of fermentation products and to speciality markets, but processes and approaches to the market are not as yet developed.
  3. There is potential for the establishment of Graminaceous species - specifically for non- food use. For European conditions particular attention is being given to Miscanthus sinensis (Miscanthus), Arundo donax (Giant Reed), Phalaris …


Grasses As Biofactories: Scoping Out The Opportunities, Nick Roberts, K. Richardson, G. Bryan, Christine R. Voisey, W. Mcnabb, T. Conner, M. Christey, R. Johnson Jan 2023

Grasses As Biofactories: Scoping Out The Opportunities, Nick Roberts, K. Richardson, G. Bryan, Christine R. Voisey, W. Mcnabb, T. Conner, M. Christey, R. Johnson

IGC Proceedings (1977-2023)

  1. Plant biopharming is set to dominate commercial recombinant protein expression for specific proteins.
  2. The choice of plant species depends on a multitude of factors and is determined on a case- by-case basis.
  3. As a leaf based expression system grasses would have to compete predominantly with tobacco and alfalfa.
  4. The grass-endophyte symbiosis offers a number of unique possibilities for biopharming.


Adoption Of Tropical Legume Technology Around The World: Analysis Of Success, H. M. Shelton, Steven Franzel, M. Peters Jan 2023

Adoption Of Tropical Legume Technology Around The World: Analysis Of Success, H. M. Shelton, Steven Franzel, M. Peters

IGC Proceedings (1977-2023)

  1. Examples of successful adoption of forage legumes are reported from all continents, where they delivered profitability and often provided multipurpose benefits to farmers.
  2. Factors vital to successful adoption were: meeting the needs of farmers; building relevant partnerships; understanding the socio-economic context and skills of farmers; participatory involvement with rural communities; and long-term involvement of champions.
  3. Organisation of seed supply, achieving scale-up and forming partnerships to implement adoption are key features.
  4. Legumes remain an important but under-exploited resource for tropical farming systems. The alternative to legumes will be greater and more costly use of N-fertilisers and purchased protein concentrates.
  5. The R&D …


Evolution Of Integrated Crop-Livestock Production Systems, Martin H. Entz, William D. Bellotti, J. M. Powell, S. V. Angadi, W. Chen, K. H. Ominski, B. Boelt Jan 2023

Evolution Of Integrated Crop-Livestock Production Systems, Martin H. Entz, William D. Bellotti, J. M. Powell, S. V. Angadi, W. Chen, K. H. Ominski, B. Boelt

IGC Proceedings (1977-2023)

  1. Many factors contribute to changes in the crop-livestock systems, but no logical end-point in the evolution process exists.
  2. While benefits of integrated crop-livestock systems over specialised crop and livestock systems are well documented, there has been a move to specialised crop and livestock production.
  3. Sustainability issues (manure nutrient concentration, soil quality maintenance, salinity, herbicide resistance, economic instability) have created a renewed interest in integrated crop-livestock systems.
  4. Farmer adaptability is as an important link in the evolution between ‘states of integration’.


Overcoming Seasonality Of Production: Opportunities Offered By Forage Conservation Technologies, P. O'Kiely, A. G. Kaiser Jan 2023

Overcoming Seasonality Of Production: Opportunities Offered By Forage Conservation Technologies, P. O'Kiely, A. G. Kaiser

IGC Proceedings (1977-2023)

  1. Seasonality of forage supply is a key contributor to the seasonality of meat and milk production.
  2. Conserving forages as silage or hay can help reduce the seasonality of feed supply.
  3. Forage conservation technologies make this contribution mainly through increases in the yield or quality of suitable crops, through an improved efficiency of the conservation process or by allowing a reduction in costs.
  4. Future research needs differ considerably among regions of the world.


Strategies To Mitigate Seasonality Of Production In Grassland-Based Systems, Claudio Porqueddu, S. Maltoni, J. G. Mcivor Jan 2023

Strategies To Mitigate Seasonality Of Production In Grassland-Based Systems, Claudio Porqueddu, S. Maltoni, J. G. Mcivor

IGC Proceedings (1977-2023)

  1. Fertilisation use and manipulation can cost-effectively alter species composition, increase seasonal herbage production and improve herbage quality.
  2. Choice of suitable grassland species, varieties and mixtures offers opportunity to mitigate limitations of seasonal grassland production.
  3. Special purpose fodder crops, cereals, shrubs and trees offer alternative or supplementary feed sources.
  4. Manipulation of stocking rates, grazing systems, transhumance and pasture management at various times of the season are significant advantageous options.
  5. Integration of different strategies is essential to mitigate seasonality in systems of animal production that must be inherently more sustainable over a longer time frame.


Interactions Between Foraging Behaviour Of Herbivores And Grassland Resources In The Eastern Eurasian Steppes, Deli Wang, Guodong Han, Yuguang Bai Jan 2023

Interactions Between Foraging Behaviour Of Herbivores And Grassland Resources In The Eastern Eurasian Steppes, Deli Wang, Guodong Han, Yuguang Bai

IGC Proceedings (1977-2023)

  1. In rangeland areas such as the eastern Eurasian steppes (Mongolia and China), foraging behaviour is influenced by plant or vegetation properties with high heterogeneity.
  2. Until recently foraging theory has not accounted for the foraging process or ingestive behaviour. Existing theories on foraging behaviour need to evolve and begin to coalesce, and combine with observations or manipulative experiments.
  3. Plant and patch properties such as diversity and height influence animal foraging behaviour (related to foraging process or diet selection) in heterogeneous steppes.
  4. Stocking rate is the most important management factor for grazing or vegetation management, and determining the optimal stocking rate in …


Foraging Behaviour And Herbage Intake In The Favourable Tropics/Sub-Tropics, S. C. Da Silva, Paulo C. De F. Carvalho Jan 2023

Foraging Behaviour And Herbage Intake In The Favourable Tropics/Sub-Tropics, S. C. Da Silva, Paulo C. De F. Carvalho

IGC Proceedings (1977-2023)

  1. Herbage intake by animals grazing tropical/sub-tropical pastures is directly related to bite mass, as it is for those grazing temperate pastures.
  2. Where these swards have low proportions of stem and dead material (controlled swards), herbage intake follows a similar pattern to that of temperate pasture species, but leaf characteristics, such as lamina length play an important role and influence the short-term rate of intake.
  3. Sward structural characteristics and behavioural factors are relatively more important than nutritional factors in terms of herbage intake regulation. The feeding value of the herbage produced is potentially adequate to sustain high levels of beef cattle …


Assessing Ecosystem Health Through Contaminants In The Tijuana River National Estuarine Research Reserve, Nancy Torres Jan 2023

Assessing Ecosystem Health Through Contaminants In The Tijuana River National Estuarine Research Reserve, Nancy Torres

Theses

Although the Tijuana River Estuary (TRE) remains the largest, most-intact coastal wetland in Southern California, it has a history of major changes, much of this related to its location immediately north of the US / Mexico Border. One of the primary challenges is cross-border flows from the rapidly growing city of Tijuana, Baja California, Mexico, and the delivery of wastewater, debris, and sediment to sensitive coastal wetland ecosystems. There is a need to more fully investigate these environmental changes to assess the ecosystem health of the Tijuana River Estuary over time, especially related to pollution impacts. This can inform an …


Columbia River Rhyolites: Age-Distribution Patterns And Their Implications For Arrival, Location, And Dispersion Of Continental Flood Basalt Magmas In The Crust, Martin J. Streck, Vanessa M. Swenton, William C. Mcintosh, Matt Heizler Jan 2023

Columbia River Rhyolites: Age-Distribution Patterns And Their Implications For Arrival, Location, And Dispersion Of Continental Flood Basalt Magmas In The Crust, Martin J. Streck, Vanessa M. Swenton, William C. Mcintosh, Matt Heizler

Geology Faculty Publications and Presentations

Columbia River province magmatism is now known to include abundant and widespread rhyolite centers even though the view that the earliest rhyolites erupted from the McDermitt Caldera and other nearby volcanic fields along the Oregon–Nevada state border has persisted. Our study covers little-studied or unknown rhyolite occurrences in eastern Oregon that show a much wider distribution of older centers. With our new data on distribution of rhyolite centers and ages along with literature data, we consider rhyolites spanning from 17.5 to 14.5 Ma of eastern Oregon, northern Nevada, and western Idaho to be a direct response to flood basalts of …


Looking Backward And Forward: Volcanology In The Years 2000, 2010, 2020, And Beyond, Jonathan Fink, Katharine Cashman Jan 2023

Looking Backward And Forward: Volcanology In The Years 2000, 2010, 2020, And Beyond, Jonathan Fink, Katharine Cashman

Geology Faculty Publications and Presentations

Figuring out how volcanoes work is one of the geoscience’s most complex puzzles. Clues of all sizes, shapes, and colors are scattered across every continent, the bottom of the ocean, in the atmosphere, and on the surfaces of other planets. Generations of geologists, geophysicists, geodesists, and geochemists have used field observations, laboratory measurements, and theory to fill gaps left by their predecessors. Yet critical uncertainties remain. Why do eruptions begin? What determines their intensity? What controls their frequency and style of activity? What causes them to end? These unsolved issues leave society increasingly vulnerable to volcanic disruptions. Hundreds of published …


Soil Microbial Legacies Influence Freeze–Thaw Responses Of Soil, Melissa A. Pastore, Aimee T. Classen, Marie E. English, Serita D. Frey, Melissa A. Knorr, Karin Rand, E. Carol Adair Jan 2023

Soil Microbial Legacies Influence Freeze–Thaw Responses Of Soil, Melissa A. Pastore, Aimee T. Classen, Marie E. English, Serita D. Frey, Melissa A. Knorr, Karin Rand, E. Carol Adair

Faculty Publications

Warmer winters with less snowfall are increasing the frequency of soil freeze–thaw cycles across temperate regions. Soil microbial responses to freeze–thaw cycles vary and some of this variation may be explained by microbial conditioning to prior winter conditions, yet such linkages remain largely unexplored. We investigated how differences in temperature history influenced microbial community composition and activity in response to freeze–thaw cycles.

We collected soil microbial communities that developed under colder (high elevation) and warmer (low elevation) temperature regimes in spruce-fir forests, then added each of these soil microbial communities to a sterile bulk-soil in a laboratory microcosm experiment. The …


Sediment Transport And Geomorphological Evolution In The Northern Gulf Of Mexico, Kelli Moran Jan 2023

Sediment Transport And Geomorphological Evolution In The Northern Gulf Of Mexico, Kelli Moran

LSU Doctoral Dissertations

This dissertation explores the mechanisms driving sediment transport and deposition on the continental shelf and within the bays of the northern Gulf of Mexico via a suite of geophysical methods and sediment cores on a variety of timescales. This dissertation is comprised of three main chapters, each focusing on a different location, environment, and process but tied together using geophysical survey, a thematic focus on geomorphic change and sediment transport within the deltaic cycle and deltaic plain environments, and the implications this change poses for both past and future sediment transport and environmental change in response to sea level change. …


Regenerative Agriculture - A Literature Review On The Practices And Mechanisms Used To Improve Soil Health, Ravjit Khangura, David Ferris, Cameron Wagg, Jamie Bowyer Jan 2023

Regenerative Agriculture - A Literature Review On The Practices And Mechanisms Used To Improve Soil Health, Ravjit Khangura, David Ferris, Cameron Wagg, Jamie Bowyer

Natural Resources Research Articles

Conventional farming practices can lead to soil degradation and a decline in productivity. Regenerative agriculture (RA) is purported by advocates as a solution to these issues that focuses on soil health and carbon sequestration. The fundamental principles of RA are to keep the soil covered, minimise soil disturbance, preserve living roots in the soil year round, increase species diversity, integrate livestock, and limit or eliminate the use of synthetic compounds (such as herbicides and fertilisers). The overall objectives are to rejuvenate the soil and land and provide environmental, economic, and social benefits to the wider community. Despite the purported benefits …


Abdoo, Mary, 1913-1990 (Sc 3668), Manuscripts & Folklife Archives Jan 2023

Abdoo, Mary, 1913-1990 (Sc 3668), Manuscripts & Folklife Archives

Manuscript Collection Finding Aids

Finding aid and scan (Click on "Additional Files" below) for Manuscripts Small Collection 3668. “The Elk Horn Coal Corporation,” by Mary Abdoo. The 1935 report examines Elkhorn coal as well as the corporation’s history, officers, and financial status. Includes a letter from the author outlining the company’s approval of the report.


Time Domain Reflectometry Waveform Interpretation With Convolutional Neural Networks, Zhuangji Wang, Shan Hua, Dennis Timlin, Yuki Kojima, Songtao Lu, Wenguang Sun, David Fleisher, Robert Horton, Vangimalla R. Reddy, Katherine Tully Jan 2023

Time Domain Reflectometry Waveform Interpretation With Convolutional Neural Networks, Zhuangji Wang, Shan Hua, Dennis Timlin, Yuki Kojima, Songtao Lu, Wenguang Sun, David Fleisher, Robert Horton, Vangimalla R. Reddy, Katherine Tully

Nebraska Water Center: Faculty Publications

Interpreting time domain reflectometry (TDR) waveforms obtained in soils with non-uniform water content is an open question. We design a new TDR waveform interpretation model based on convolutional neural networks (CNNs) that can reveal the spatial variations of soil relative permittivity and water content along a TDR sensor. The proposed model, namely TDR-CNN, is constructed with three modules. First, the geometrical features of the TDR waveforms are extracted with a simplified version of VGG16 network. Second, the reflection positions in a TDR waveform are traced using a 1D version of the region proposal network. Finally, the soil relative permittivity values …


Near-Cloud Atmospheric Ingredients For Deep Convection Initiation, James N. Marquis, Zhe Feng, Adam Varble, T. Connor Nelson, Adam L. Houston, John M. Peters, Jake P. Mulholland, Joseph Hardi Jan 2023

Near-Cloud Atmospheric Ingredients For Deep Convection Initiation, James N. Marquis, Zhe Feng, Adam Varble, T. Connor Nelson, Adam L. Houston, John M. Peters, Jake P. Mulholland, Joseph Hardi

Department of Earth and Atmospheric Sciences: Faculty Publications

A lack of routine environmental observations located near deepening cumulus congestus clouds limits verification of important theorized and simulated updraft–environment interaction processes occurring during deep convection initiation (CI). We analyze radiosonde profiles collected during several hundred CI events near a mountain range in central Argentina during the CACTI field campaign. Statistical analyses illustrate environmental conditions supporting radar-observed CI outcomes that span a spectrum of convective cell depths, widths, and durations, as well as events lacking precipitating convection. Tested environmental factors include a large variety of sounding-derived measurements of CAPE, CIN, moisture, terrain-relative winds, vertical shear, and lifted parcel properties, with …


The Kanarra Fold-Thrust Structure - The Leading Edge Of The Sevier Fold-Thrust Belt, Southwestern Utah: Geology Of The Intermountain West, William J. Chandonia, John P. Hogan Jan 2023

The Kanarra Fold-Thrust Structure - The Leading Edge Of The Sevier Fold-Thrust Belt, Southwestern Utah: Geology Of The Intermountain West, William J. Chandonia, John P. Hogan

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The multiple origins proposed for the Kanarra anticline in southwestern Utah as a drag-fold along the Hurricane fault, a Laramide monocline, a Sevier fault-propagation fold, or a combination of these process­es, serve to muddy its tectonic significance. This in part reflects the structural complexity of the exposed eastern half of the fold. The fold evolved from open and up-right to overturned and tight, is cross-cut by multiple faults, and was subsequently dismembered by the Hurricane fault. The western half of the fold is obscured because of burial, along with the hanging wall of the Hurricane fault, beneath Neogene and younger …


20th To 21st Century Relative Sea And Land Level Changes In Northern California: Tectonic Land Level Changes And Their Contribution To Sea-Level Rise, Humboldt Bay Region, Northern California, Jason R. Patton, Todd B. Williams, Jeffrey K. Anderson, Mark Hemphill-Haley, Reed J. Burgette, Ray Weldon Ii, Robert C. Mcpherson, Thomas H. Leroy Jan 2023

20th To 21st Century Relative Sea And Land Level Changes In Northern California: Tectonic Land Level Changes And Their Contribution To Sea-Level Rise, Humboldt Bay Region, Northern California, Jason R. Patton, Todd B. Williams, Jeffrey K. Anderson, Mark Hemphill-Haley, Reed J. Burgette, Ray Weldon Ii, Robert C. Mcpherson, Thomas H. Leroy

Local Reports and Publications

Sea-level changes are modulated in coastal northern California by land-level changes due to the earthquake cycle along the Cascadia subduction zone, the San Andreas plate boundary fault system, and crustal faults. Sea-level rise (SLR) subjects ecological and anthropogenic infrastructure to increased vulnerability to changes in habitat and increased risk for physical damage. The degree to which each of these forcing factors drives this modulation is poorly resolved. We use NOAA tide gage data and ‘campaign’ tide gage deployments, Global Navigation Satellite System (GNSS) data, and National Geodetic Survey (NGS) first-order levelling data to calculate vertical land motion (VLM) rates in …


Mg Records Of Two Stalagmites From B7-Cave (Northwest Germany) Indicating Long-Term Precipitation Changes During Early To Mid-Holocene, Dana F. C. Riechelmann, Klaus Peter Jochum, Detlev K. Richter, Denis Scholz Jan 2023

Mg Records Of Two Stalagmites From B7-Cave (Northwest Germany) Indicating Long-Term Precipitation Changes During Early To Mid-Holocene, Dana F. C. Riechelmann, Klaus Peter Jochum, Detlev K. Richter, Denis Scholz

International Journal of Speleology

Two stalagmites from B7-Cave in northwest Germany, which is part of the same cave system as the intensively studied Bunker Cave, were re-dated by multi collector inductively coupled plasma mass spectrometry (MC-ICPMS) 230Th/U-dating. Furthermore, the concentration of Mg, Sr, Ba, P, Y, Zn, and Al were determined at high-resolution by laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS). Stalagmite B7-1 grew from 10.8 to 5.8 ka BP. Stalagmite B7-7 grew during three growth phases from 11.0 to 6.2, 3.13 to 2.86 (late Bronze Age), and 1.27 to 1.15 ka BP (early Medieval Period). Aluminium is a proxy for detrital …


Linking The Pinware, Baraboo, And Picuris Orogens: Recognition Of A Trans-Laurentian Ca. 1520–1340 Ma Orogenic Belt, Christopher G. Daniel, Aphrodite Indares, L. Gordon Medaris Jr., Ruth Aronoff, David H. Malone, Joshua Schwartz Jan 2023

Linking The Pinware, Baraboo, And Picuris Orogens: Recognition Of A Trans-Laurentian Ca. 1520–1340 Ma Orogenic Belt, Christopher G. Daniel, Aphrodite Indares, L. Gordon Medaris Jr., Ruth Aronoff, David H. Malone, Joshua Schwartz

Faculty Publications - Geography, Geology, and the Environment

It is proposed that the Pinware orogen of eastern Canada, the Baraboo orogen of the midcontinent, and the Picuris orogen of the southwestern United States delineate a previously unrecognized, ~5000-km-long, ca. 1520–1340 Ma trans-Laurentian orogenic belt. All three orogenic provinces are characterized by Mesoproterozoic sedimentation, magmatism, metamorphism, and deformation—the hallmarks of a tectonically active plate margin. Tectonism was diachronous, with the earliest stages beginning ca. 1520 Ma in eastern Canada and ca. 1500 Ma in the southwest United States. Magmatic zircon age distributions are dominated by Mesoproterozoic, unimodal to multimodal age peaks between ca. 1500 and 1340 Ma. The onset …


First-Principles Molecular Dynamics Study Of Liquid Iron-Rich Alloys Under Conditions Of The Earth’S Core, Dipendra Banjara Jan 2023

First-Principles Molecular Dynamics Study Of Liquid Iron-Rich Alloys Under Conditions Of The Earth’S Core, Dipendra Banjara

LSU Doctoral Dissertations

In this dissertation, we report the results of the first-principles molecular dynamics (FPMD) simulations and data analysis on the thermodynamic, structural, and transport properties of iron-rich metallic liquids considering several light and heavy elements under wide ranges of pressure and temperature that are relevant to the earth’s core. Our simulations of pure liquid iron cover the pressure range from 0 GPa at 2000 K to 380 GPa at 7000 K perhaps representing the most extensive computational study to date. We studied four molten iron-rich alloys corresponding to 2.67 atom% of Ni, Co, Mo, and W at pressures up to 380 …


Improving The Quality Of Products From Grassland, Nigel D. Scollan, R. J. Dewhurst, A. P. Moloney, J. J. Murphy Jan 2023

Improving The Quality Of Products From Grassland, Nigel D. Scollan, R. J. Dewhurst, A. P. Moloney, J. J. Murphy

IGC Proceedings (1977-2023)

  1. Consumers are increasingly aware of the links between diet and health, and place increasing emphasis on nutritional quality as a component of product quality.
  2. Meat and milk products are rich sources of nutrients such as omega-3 (n-3) fatty acids and conjugated linoleic acid, which offer health benefits to consumers.
  3. Green plants are the primary source of n-3 fatty acids in the food chain.
  4. Grassland production systems have the potential to enhance the content of beneficial fatty acids, improve stability (from higher antioxidant content) and alter sensory attributes of meat and milk.
  5. Grassland offers considerable scope to help …