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Geospatial Analyses Of Seismic Hazards And Risk Perception In Libya, Somaia Suwihli Jul 2020

Geospatial Analyses Of Seismic Hazards And Risk Perception In Libya, Somaia Suwihli

Graduate Theses and Dissertations

Libya is not considered a highly active seismic region. However, several earthquakes of magnitude >5.0 have occurred there. This dissertation analyzes the seismicity of Libya in order to better understand earthquake hazards, related geomorphic features, and the current evolution of Libyan perceptions of seismic risk. The first article developed a baseline of past and current seismic inventory in Libya, which represented an assessment of Libya seismic hazard by translating, analyzing, and compiling historical sources and archaeological data. This study shows that Libya has experienced earthquakes in varying degrees since ancient times. Through the spatial and temporal distribution of earthquakes from …


Perceptions Of A Small Midwestern Food Cooperative: A Case Study, Rebecca Forsythe Jul 2020

Perceptions Of A Small Midwestern Food Cooperative: A Case Study, Rebecca Forsythe

Theses and Dissertations

The purpose of this research is to illuminate how individuals form perceptions of cooperatives, specifically of Green Top Grocery, a cooperative located in Bloomington Illinois, using the Bourdieu-sian habitus and notions of capital as a frame. Green Top Grocery suffers from fiscal instability since they opened in 2017. They also struggle to gain support of lower income individuals, a key demographic they sought to help since their inception based on their stated values. By conducting qualitative interviews of three sample groups: Green Top Grocery board members and leadership, local food access experts, and West Bloomington residents, and non-participant observations, this …


Soil-Plant Nutrient Cycling In Old Cocoa Farms In A Part Of South Western Nigerian Forest Belt, Olusola Afolayan Jun 2020

Soil-Plant Nutrient Cycling In Old Cocoa Farms In A Part Of South Western Nigerian Forest Belt, Olusola Afolayan

Tanzania Journal of Science

Apart from pests and diseases, a vital issue in the early mature of cocoa crop in Nigeria is soil nutrient degradation in relation to the ageing of the farms and annual mining of nutrients via yield harvests. Indigenous production of cocoa in southwest Nigeria has been on without fertilizer applications. This is the basis for the reduction average lifespan and productive years of the plantation. The aim of this study was to quantify the rates of soil nutrient losses via cycling channels in old cocoa farm using cocoa beans, leaves, litters, and pod husks in south western Nigeria forest belt. …


Variability Of Selected Mineral Contents In Marine Fish From Local Markets In Tanzania, Stella Shija, Matobola Mihale, Daniel Shilla Jun 2020

Variability Of Selected Mineral Contents In Marine Fish From Local Markets In Tanzania, Stella Shija, Matobola Mihale, Daniel Shilla

Tanzania Journal of Science

Mineral contents (K, Na, Ca and Mg) in selected marine fish species (Alectis ciliaris, Lethrinus harak, Rastrelliger kanagurta and Siganus canaliculatus) from local fish markets were analysed in wet and dry seasons. The processing methods (frying and boiling) were also assessed for their influence on the mineral contents. Samples were randomly collected from Tanga, Bagamoyo, Dar es Salaam and Mtwara seaports, analysed using established methods and determined by Graphite Furnace Atomic Absorption Spectrometry. Mean mineral contents in individual and all analysed fish species were high during dry season compared to wet season except Ca and the difference was statistically significant …


Water Environment Comprehensive Forewarning For Waterlogged Area In Huainan Based On Weber-Fechner Law, Pei Wenming, Zhang Hui, Ju Changhua, Yao Suping, Ren Yongle, Ma Mengxiao, Qiu Kuanbiao Jun 2020

Water Environment Comprehensive Forewarning For Waterlogged Area In Huainan Based On Weber-Fechner Law, Pei Wenming, Zhang Hui, Ju Changhua, Yao Suping, Ren Yongle, Ma Mengxiao, Qiu Kuanbiao

Coal Geology & Exploration

In area with high groundwater level in the east of China, long-time underground coal mining results in a large subsidence water area on the surface. The risk of water environment pollution in subsidence waters is increasing gradually with the influence of human activities. According to Weber-Fisher law, this paper took Panji waterlogged area of Huainan as the research object, selected the water quality evaluation indexes closely related to the water environment of the waterlogged area, analyzed the water environmental conditions of the waterlogged area in different periods, and quantitatively reflected the time and the area of the water environment quality …


Development Of A Benthic Foraminifera Based Marine Biotic Index (Foram-Ambi) For The Gulf Of Mexico: A Decision Support Tool, Bryan O'Malley Jun 2020

Development Of A Benthic Foraminifera Based Marine Biotic Index (Foram-Ambi) For The Gulf Of Mexico: A Decision Support Tool, Bryan O'Malley

USF Tampa Graduate Theses and Dissertations

The Gulf of Mexico (GoM) is an economically important region (e.g. oil and gas, fisheries) and with the expansion of oil drilling, harmful algal bloom events, oil blowouts, dead zones, anthropogenic eutrophication and contaminant loading, it is important that the ecological quality statuses (EcoQS) of different localities in the Gulf are closely monitored. The EcoQS, as implemented by the European Water Framework Directive, is an effective tool for monitoring ecological health and developing reference conditions. One such index used to define EcoQS is the AZTI Marine Biotic Index (AMBI), which pairs species abundance with environmental stressors. Benthic foraminifera are ideal …


Anthropogenically Expedited Transit Reduces Organic Carbon Loss In The Lower Mississippi River: Dataset, Zhixiong Shen, Brad E. Rosenheim, Torbjörn E. Törnqvist, Andreas Lang Jun 2020

Anthropogenically Expedited Transit Reduces Organic Carbon Loss In The Lower Mississippi River: Dataset, Zhixiong Shen, Brad E. Rosenheim, Torbjörn E. Törnqvist, Andreas Lang

College of Science Data Sets

This dataset presents data to investigate the change of organic carbon carried by the Lower Mississippi River (LMR) related to river engineering. The dataset includes (1) OSL data, (2) 14C data; (3) the channel centerline of the LMR in the 1970s, (4) the channel centerline of the LMR in 2019, and (5) the migration rates of the LMR between the 1970s and 2019.


Long-Term Ndvi And Recent Vegetation Cover Profiles Of Major Offshore Island Nesting Sites Of Sea Turtles In Saudi Waters Of The Northern Arabian Gulf, Rommel H. Maneja, Jeffrey D. Miller, Wenzhao Li, Hesham El-Askary, Ace Vincent B. Flandez, Joshua J. Dagoy, Joselito Francis A. Alcaria, Abdullajid U. Basali, Khaled A. Al-Abdulkader, Ronald A. Loughland, Mohamed A. Qurban Jun 2020

Long-Term Ndvi And Recent Vegetation Cover Profiles Of Major Offshore Island Nesting Sites Of Sea Turtles In Saudi Waters Of The Northern Arabian Gulf, Rommel H. Maneja, Jeffrey D. Miller, Wenzhao Li, Hesham El-Askary, Ace Vincent B. Flandez, Joshua J. Dagoy, Joselito Francis A. Alcaria, Abdullajid U. Basali, Khaled A. Al-Abdulkader, Ronald A. Loughland, Mohamed A. Qurban

Mathematics, Physics, and Computer Science Faculty Articles and Research

Vegetation is an important ecological component of offshore islands in the Arabian Gulf (AG), which maintains long-term resilience of these islands. This is achieved by influencing sediment retention and moisture acquisition via condensation during periods of high humidity and by providing a variety of microhabitats for island fauna. The resilience of offshore islands’ ecosystems in the Saudi waters is important because they host the largest number of nesting hawksbill and green turtles in the AG. This study defines the characteristics and the long-term trends in vegetation cover of the offshore islands used by sea turtles as nesting grounds in the …


The State Of Forage Germplasm Resources In Yunnan Province, Zhenzhong Sun, Jun Yin, Qiao Wei Jun 2020

The State Of Forage Germplasm Resources In Yunnan Province, Zhenzhong Sun, Jun Yin, Qiao Wei

IGC Proceedings (1977-2023)

No abstract provided.


Benchmarking And Parameter Sensitivity Of Physiological And Vegetation Dynamics Using The Functionally Assembled Terrestrial Ecosystem Simulator (Fates) At Barro Colorado Island, Panama, Charles D. Koven, Ryan G. Knox, Rosie A. Fisher, Jeffrey Q. Chambers, Bradley O. Christoffersen, Stuart J. Davies, Matteo Detto Jun 2020

Benchmarking And Parameter Sensitivity Of Physiological And Vegetation Dynamics Using The Functionally Assembled Terrestrial Ecosystem Simulator (Fates) At Barro Colorado Island, Panama, Charles D. Koven, Ryan G. Knox, Rosie A. Fisher, Jeffrey Q. Chambers, Bradley O. Christoffersen, Stuart J. Davies, Matteo Detto

School of Earth, Environmental, & Marine Sciences Faculty Publications

Plant functional traits determine vegetation responses to environmental variation, but variation in trait values is large, even within a single site. Likewise, uncertainty in how these traits map to Earth system feedbacks is large. We use a vegetation demographic model (VDM), the Functionally Assembled Terrestrial Ecosystem Simulator (FATES), to explore parameter sensitivity of model predictions, and comparison to observations, at a tropical forest site: Barro Colorado Island in Panama. We define a single 12-dimensional distribution of plant trait variation, derived primarily from observations in Panama, and define plant functional types (PFTs) as random draws from this distribution. We compare several …


Combined Use Of Sentinel‐1 Sar And Landsat Sensors Products For Residual Soil Moisture Retrieval Over Agricultural Fields In The Upper Blue Nile Basin, Ethiopia, Getachew Ayehu, Tsegaye Tadesse, Berhan Gessesse, Yibeltal Yigrem, Assefa M. Melesse Jun 2020

Combined Use Of Sentinel‐1 Sar And Landsat Sensors Products For Residual Soil Moisture Retrieval Over Agricultural Fields In The Upper Blue Nile Basin, Ethiopia, Getachew Ayehu, Tsegaye Tadesse, Berhan Gessesse, Yibeltal Yigrem, Assefa M. Melesse

National Drought Mitigation Center: Faculty Publications

The objective of this paper is to investigate the potential of sentinel‐1 SAR sensor products and the contribution of soil roughness parameters to estimate volumetric residual soil moisture (RSM) in the Upper Blue Nile (UBN) basin, Ethiopia. The backscatter contribution of crop residue water content was estimated using Landsat sensor product and the water cloud model (WCM). The surface roughness parameters were estimated from the Oh and Baghdadi models. A feed‐forward artificial neural network (ANN) method was tested for its potential to translate SAR backscattering and surface roughness input variables to RSM values. The model was trained for three inversion …


Recent Shrinkage And Fragmentation Of Bluegrass Landscape In Kentucky, Bo Tao, Yanjun Yang, Jia Yang, S. Ray Smith, James F. Fox, Alex C. Ruane, Jinze Liu, Wei Ren Jun 2020

Recent Shrinkage And Fragmentation Of Bluegrass Landscape In Kentucky, Bo Tao, Yanjun Yang, Jia Yang, S. Ray Smith, James F. Fox, Alex C. Ruane, Jinze Liu, Wei Ren

Plant and Soil Sciences Faculty Publications

The Bluegrass Region is an area in north-central Kentucky with unique natural and cultural significance, which possesses some of the most fertile soils in the world. Over recent decades, land use and land cover changes have threatened the protection of the unique natural, scenic, and historic resources in this region. In this study, we applied a fragmentation model and a set of landscape metrics together with the satellite-derived USDA Cropland Data Layer to examine the shrinkage and fragmentation of grassland in the Bluegrass Region, Kentucky during 2008–2018. Our results showed that recent land use change across the Bluegrass Region is …


Wrack & Ruin: A Tale Of Tortured Trees, John T. Van Stan Ii, Albertus Tyasseta, Siloy, Graphic Artist Jun 2020

Wrack & Ruin: A Tale Of Tortured Trees, John T. Van Stan Ii, Albertus Tyasseta, Siloy, Graphic Artist

Earth, Environment & Sustainability: Faculty Bookshelf

Here, we visit a community of trees living along the Georgia coast, just above the high tide line, on a little lump of sand called a "hammock." This hammock plant community is battered by a hurricane. The plants that survive soon realize that they have fallen prey to a hydrological torture wrack - one composed of the salty corpses of their neighboring marsh plants (Spartina alterniflora). This sci comic is based on the publication, "Wrack and ruin: Legacy hydrologic effects of hurricane-deposited wrack..." (https://doi.org/10.1088/2515-7620/ab9527).


Wrack And Ruin: Legacy Hydrologic Effects Of Hurricane-Deposited Wrack On Hardwood-Hammock Coastal Islands, John T. Van Stan Ii, Scott T. Allen, Travis Swanson Jun 2020

Wrack And Ruin: Legacy Hydrologic Effects Of Hurricane-Deposited Wrack On Hardwood-Hammock Coastal Islands, John T. Van Stan Ii, Scott T. Allen, Travis Swanson

Earth, Environment & Sustainability: Faculty Publications

Hurricanes can cause immediate catastrophic destruction of marsh vegetation and erosion of soils; however, they also have long-lasting ecological impacts. Those impacts include the deposition of tremendous amounts of saltmarsh litter ('wrack') onto upland ecosystems, the hydrologic effects of which have not previously been investigated. When Hurricane Irma battered the southeastern US coastline, widespread wrack deposition was reported (often exceeding 0.5 m depth), especially in vulnerable coastal hammock ecosystems: locally-elevated forests within the saltmarshes that rely on freshwater inputs from rain. We report the impacts of this deposited wrack, which has persisted for 2 years, on effective precipitation inputs to …


Heavy Metals In The Arctic: Distribution And Enrichment Of Five Metals In Alaskan Soils, Clarice R. Perryman, Jochen Wirsing, Kathryn A. Bennett, Owen Brennick, Apryl L. Perry, Nicole Williamson, Jessica G. Ernakovich Jun 2020

Heavy Metals In The Arctic: Distribution And Enrichment Of Five Metals In Alaskan Soils, Clarice R. Perryman, Jochen Wirsing, Kathryn A. Bennett, Owen Brennick, Apryl L. Perry, Nicole Williamson, Jessica G. Ernakovich

Faculty Publications

Metal contamination of food and water resources is a known public health issue in Arctic and sub-Arctic communities due to the proximity of many communities to mining and drilling sites. In addition, permafrost thaw may release heavy metals sequestered in previously frozen soils, potentially contaminating food and water resources by increasing the concentration of metals in freshwater, plants, and wildlife. Here we assess the enrichment of selected heavy metals in Alaskan soils by synthesizing publicly available data of soil metal concentrations. We analyzed data of soil concentrations of arsenic, chromium, mercury, nickel, and lead from over 1,000 samples available through …


Characterizing Surface Water From Space With Microwave Remote Sensing: Advancing Conventional And Emerging Approaches, Katherine Jensen Jun 2020

Characterizing Surface Water From Space With Microwave Remote Sensing: Advancing Conventional And Emerging Approaches, Katherine Jensen

Dissertations, Theses, and Capstone Projects

The extent and dynamics of land surface inundation vary tremendously across the globe. Accurate spatial representation of terrestrial surface water is of critical importance for management and conservation of biodiversity and other ecosystem services associated with freshwater. Furthermore, surface water maps representing dynamic characteristics of inundated areas are also valuable for the development of wetland inventories and to assess the role of wetlands as major natural sources of methane to the atmosphere. Despite the importance of these environments in global processes and to current and future climate, the extent and dynamics of global wetlands remain poorly characterized and modeled.

The …


Physical And Chemical Properties Of Soils In Gambari Forest Reserve Near Ibadan, South Western Nigeria., Akintola O. Opeyemi Dr, Bodede Idayat Adewunmi Dr, Abiola Isaac Oluwaseyi Dr Jun 2020

Physical And Chemical Properties Of Soils In Gambari Forest Reserve Near Ibadan, South Western Nigeria., Akintola O. Opeyemi Dr, Bodede Idayat Adewunmi Dr, Abiola Isaac Oluwaseyi Dr

Journal of Bioresource Management

The different features of soil greatly affect the flora and vegetative diversity of a forest. The physical and chemical characteristics of soils in Onigambari Forest Reserve were evaluated to assess the fertility and productivity status of the soils. Fifteen soil samples collected from different sample locations were analyzed for soil texture (sand, silt and clay), bulk density, porosity, pH, organic matter, total nitrogen, available phosphorus, exchangeable bases (Na, K, Ca and Mg) and available micronutrients (Zn, Cu, Fe and Mn). Texturally, the studied soils were loamy sand and sandy loam with percentage of sands (71.2-84.2 %), silts (7.4-10.4 %) and …


Geospatial Applications To Mitigate Concentrated Animal Feeding Operations From Impacting Surface Water Resources, Elias Rex Jun 2020

Geospatial Applications To Mitigate Concentrated Animal Feeding Operations From Impacting Surface Water Resources, Elias Rex

Electronic Theses, Projects, and Dissertations

Concentrated Animal Feeding Operations (CAFOs) offer the ability to meet the rising demands of population growth by housing large amounts of livestock on relatively small areas of land, using medication to accelerate their maturation, and reusing waste products as fertilizers. However, there is a growing abundance of literature related to land use configurations and their effects on water resources, many of which highlight agriculture as a primary contributor of nutrients and fecal bacteria found in surrounding water resources. The purpose of this study is to advance the current knowledge surrounding CAFO land-use and its effect on tributaries within the Cape …


Sustainable Recultivation And Land Use On Karst Regions--Pasture System, Z. Q. Lai, Y. R. Chen, M. Pogacnik, S. Z. Qin, X. F. Yi, N. Yao, Y. L. Liang, J. H. Deng, X. F. Zhang, B. Zhang, H. J. Zhong, D. Kompan, X. J. Lu, X. Su, D. Y. Shen May 2020

Sustainable Recultivation And Land Use On Karst Regions--Pasture System, Z. Q. Lai, Y. R. Chen, M. Pogacnik, S. Z. Qin, X. F. Yi, N. Yao, Y. L. Liang, J. H. Deng, X. F. Zhang, B. Zhang, H. J. Zhong, D. Kompan, X. J. Lu, X. Su, D. Y. Shen

IGC Proceedings (1977-2023)

No abstract provided.


Rangeland Ecology And Management In A Changing World, Joel R. Brown, Brandon T. Bestelmeyer, Kris M. Havstad May 2020

Rangeland Ecology And Management In A Changing World, Joel R. Brown, Brandon T. Bestelmeyer, Kris M. Havstad

IGC Proceedings (1977-2023)

No abstract provided.


Storm Surges In The Bohai Sea: The Role Of Waves And Tides, Yuanyi Li, Huan Feng, Guillaume Vigouroux, Dekui Yuan, Guangyu Zhang, Xiaodi Ma, Kun Lei May 2020

Storm Surges In The Bohai Sea: The Role Of Waves And Tides, Yuanyi Li, Huan Feng, Guillaume Vigouroux, Dekui Yuan, Guangyu Zhang, Xiaodi Ma, Kun Lei

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

A storm surge is a complex phenomenon in which waves, tide and current interact. Even though wind is the predominant force driving the surge, waves and tidal phase are also important factors that influence the mass and momentum transport during the surge. Devastating storm surges often occur in the Bohai Sea, a semi-enclosed shallow sea in North China, due to extreme storms. However, the effects of waves on storm surges in the Bohai Sea have not been quantified and the mechanisms responsible for the higher surges that affect part of the Bohai Sea have not been thoroughly studied. In this …


Uas-Based Tracking Of The Santiaguito Lava Dome, Guatemala, Edgar U. Zorn, Thomas R. Walter, Jeffrey B. Johnson, René Mania May 2020

Uas-Based Tracking Of The Santiaguito Lava Dome, Guatemala, Edgar U. Zorn, Thomas R. Walter, Jeffrey B. Johnson, René Mania

Geosciences Faculty Publications and Presentations

Imaging growing lava domes has remained a great challenge in volcanology due to their inaccessibility and the severe hazard of collapse or explosion. Changes in surface movement, temperature, or lava viscosity are considered crucial data for hazard assessments at active lava domes and thus valuable study targets. Here, we present results from a series of repeated survey flights with both optical and thermal cameras at the Caliente lava dome, part of the Santiaguito complex at Santa Maria volcano, Guatemala, using an Unoccupied Aircraft System (UAS) to create topography data and orthophotos of the lava dome. This enabled us to track …


Nitrate Transport In The Unsaturated Zone, Patience Bosompemaa May 2020

Nitrate Transport In The Unsaturated Zone, Patience Bosompemaa

Theses and Dissertations

Abundance of nitrate in the soil is a basic issue in agricultural land-use regions, causing eutrophication and pollution of water bodies. The study focuses on the role of a saturated buffer zone (SBZ) to remove nitrate from the groundwater resulting from agricultural activities. The study area is herbaceous SBZ located in central Illinois (40.614382ºN, -89.023542ºW), which lies between a stream and a farm located upgradient. The SBZ has been outfitted with an agricultural runoff treatment system that diverts tile drainage into the subsurface of the SBZ rather than discharging into the stream. Within the SBZ three experimental areas composed of …


Crystal Queer: Fracturing The Binaries Of Matter, Creation, And Landscape, Sarah Knight May 2020

Crystal Queer: Fracturing The Binaries Of Matter, Creation, And Landscape, Sarah Knight

Graduate School of Art Theses

In this thesis, I compile a series of fragments consisting an analysis of my artwork in the gendered contexts of landscape, self-identity, mythology, and philosophy. I develop my concept of a “queer mark” in my art that serves as a form of queering, a disruption of visual and conceptual cohesion. I form a picture of how our contemporary selves are influenced by our gendered understanding of the landscape through the analysis of philosophical, artistic, and mythological concepts of creation. I see my sculptures as an atlas to an alternative means of understanding identity, a queering of these historical and exclusionary …


The Pantropical Response Of Soil Moisture To El Niño, Kurt C. Solander, Brent D. Newman, Alessandro Carloca De Araujo, Holly R. Barnard, Z. Carter Berry, Damien Bonal, Mario Bretfeld, Benoit Burban, Luiz Antonio Candido, Rolando Celleri, Jeffery Q. Chambers, Bradley O. Christoffersen May 2020

The Pantropical Response Of Soil Moisture To El Niño, Kurt C. Solander, Brent D. Newman, Alessandro Carloca De Araujo, Holly R. Barnard, Z. Carter Berry, Damien Bonal, Mario Bretfeld, Benoit Burban, Luiz Antonio Candido, Rolando Celleri, Jeffery Q. Chambers, Bradley O. Christoffersen

School of Earth, Environmental, & Marine Sciences Faculty Publications

The 2015–2016 El Niño event ranks as one of the most severe on record in terms of the magnitude and extent of sea surface temperature (SST) anomalies generated in the tropical Pacific Ocean. Corresponding global impacts on the climate were expected to rival, or even surpass, those of the 1997–1998 severe El Niño event, which had SST anomalies that were similar in size. However, the 2015–2016 event failed to meet expectations for hydrologic change in many areas, including those expected to receive well above normal precipitation. To better understand how climate anomalies during an El Niño event impact soil moisture, …


How Much Variation In Land Surface Phenology Can Climate Oscillation Modes Explain At The Scale Of Mountain Pastures In Kyrgyzstan?, Monika A. Tomaszewska, Geoffrey M. Henebry May 2020

How Much Variation In Land Surface Phenology Can Climate Oscillation Modes Explain At The Scale Of Mountain Pastures In Kyrgyzstan?, Monika A. Tomaszewska, Geoffrey M. Henebry

NASA Land-Cover Land-Use Change Data Sets

Climate oscillation modes can shape weather across the globe due to atmospheric teleconnections. We built on the findings of a recent study to assess whether the impacts of teleconnections are detectable and significant in the early season dynamics of highland pastures across five rayons in Kyrgyzstan. Specifically, since land surface phenology (LSP) has already shown to be influenced by snow cover seasonality and terrain, we investigated here how much more explanatory and predictive power information about climatic oscillation modes might add to explain variation in LSP. We focused on seasonal values of five climate oscillation indices that influence vegetation dynamics …


Core And Geophysical Analysis Of Biogenic Tufa Deposits In The Spring River In Northern Arkansas, Tyler W. Engelbart May 2020

Core And Geophysical Analysis Of Biogenic Tufa Deposits In The Spring River In Northern Arkansas, Tyler W. Engelbart

Graduate Theses/Dissertations

The Spring River is fed by Mammoth Spring, a large spring on the Missouri-Arkansas border which produces roughly 240 million gallons of water per day (MGD). In this area there are deposits that appear as dams which cause water to pool upstream. Aerial analysis of the dams shows that there are approximately 100 of these features present in the first 45 miles downstream of Mammoth Spring. These deposits, known as tufa, are not uncommon in a karstic area of a spring fed river, but these are more frequent farther downriver than near the mouth of the spring. Preliminary mapping data …


Pumice Compositions And Mineral Chemistry From Lascar Volcano, Chile, Madelaine M. Stearn May 2020

Pumice Compositions And Mineral Chemistry From Lascar Volcano, Chile, Madelaine M. Stearn

Graduate Theses/Dissertations

Lascar volcano is one the most active volcano in the Central Volcanic Zone of the Andean Cordillera, with 36 Holocene eruptions including a VEI 4 eruption in April 1993. Activity has not been consistent throughout time, and therefore, the processes behind it are poorly understood. Lascar volcano has cyclic behavior and has had four stages of activity, each of which had a unique eruptive style and product composition. Stage I (<43 >ka) had primarily mafic andesite lavas erupted effusively from a stratocone. Stage II initiated with dome building events ESE of the original vent and culminated in the 26.45 ka …


Evaluating The Influences Of Harvesting Activity And Eutrophication On Loss Of Aquatic Vegetations In Taihu Lake, China, Juhua Luo, Ruiliang Pu, Hongtao Duan, Ronghua Ma, Zhigang Mao, Yuan Zeng, Linsheng Huang, Qitao Xiao May 2020

Evaluating The Influences Of Harvesting Activity And Eutrophication On Loss Of Aquatic Vegetations In Taihu Lake, China, Juhua Luo, Ruiliang Pu, Hongtao Duan, Ronghua Ma, Zhigang Mao, Yuan Zeng, Linsheng Huang, Qitao Xiao

School of Geosciences Faculty and Staff Publications

A rapid degradation of aquatic vegetations in Taihu Lake has roused a wide attention in recent years. Giving large-scale harvesting activity on aquatic vegetation since 2012, whether water eutrophication or the human harvest activity induced the degradation remains controversial and unclear. In this study, based on Landsat and HJ-CCD data acquired from 1984 to 2016 and a 12-year field observation (2005–2016) of water quality, a method was proposed to quantitatively assess impacts of harvesting activity and water quality change on degradations of both floating-leaved aquatic vegetation (FAV) and submerged aquatic vegetation (SAV) in Taihu Lake. First, areas of FAV and …


Geochemistry Of The Lazufre Volcanic Complex: Determining The Geometries And Processes Of The Magmatic Sources In The Central Andean Volcanic Zone, Brooke Erin Benz May 2020

Geochemistry Of The Lazufre Volcanic Complex: Determining The Geometries And Processes Of The Magmatic Sources In The Central Andean Volcanic Zone, Brooke Erin Benz

Graduate Theses/Dissertations

The Central Andes in South America contain many active volcanoes and volcano complexes due to constant subduction producing extrusive rocks varying in composition. The Lazufre Complex, Chile-Argentina border, consists of two Pleistocene volcanic centers, Lastarria and Cordon del Azufre andesite and dacite lava flows and domes. Whole-rock K-Ar dates of lavas from Cordon del Azufre place the most recent eruptions at 0.6-0.3 Ma ±0.3 Ma. Major-element data of plagioclase and pyroxene show homogeneous compositions between the centers, which is consistent with whole rock major- and trace-element compositions. The primary composition of the pyroxenes are augite and diopsides for cpx and …