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Articles 6541 - 6570 of 29939
Full-Text Articles in Geology
Groundwater Modeling Of The West Plains, Wa, Erin L. Toulou, Chad Pritchard Phd, Lauren Stachowiak Phd
Groundwater Modeling Of The West Plains, Wa, Erin L. Toulou, Chad Pritchard Phd, Lauren Stachowiak Phd
2022 Symposium
Located in Eastern Washington in the West Plains Region sits a plateau of Columbia River Basalts between Deep Creek, Hangman Creek, and south of the Spokane River. Primarily in Airway Heights, the amount of drinking water as well as the quality of the water has affected residents in the area. The most recent issue is PFAS contamination, which is thought to negatively affect human health and is found in drinking water wells across the West Plains. We can interpret subsurface geology using new well logs from Fairchild Air Force Base and in the Palisades area. When using ArcGIS PRO, well …
Instructor Selection And Use Of Virtual Field Experiences In College Geoscience Course, Kristen Foley
Instructor Selection And Use Of Virtual Field Experiences In College Geoscience Course, Kristen Foley
Masters Theses
Virtual Field Experiences (VFEs) are a growing supplement and gateway to traditional fieldwork in the geosciences. With VFEs becoming more accepted for use in college geoscience courses, how instructors find and choose VFEs for their students is critical to creating greater accessibility and future resources. VFEs that are not easily accessed by instructors may go unused, and the effort put into making them would have been wasted. This phenomenological descriptive study utilized five focus groups of college geoscience instructors in the United States. Each 1-to-1.5-hour focus group session of 3-7 participants took place on video conferencing software, which was recorded …
Improving Asteroid Remote Sensing By Examining Past Martian Methods, James Dean King
Improving Asteroid Remote Sensing By Examining Past Martian Methods, James Dean King
Theses
Deep Space Remote Sensing is an ever-evolving field. The very first missions into deep space were explorations that utilized trial and error, as humanity faced a new frontier of unknowns. Over these 70 years of deep space exploration, much attention has been given to our three nearest celestial neighbors: the Moon, Venus, and Mars. Mars, in particular, has been the target of much observation and study due to it being a target for future colonization. Meanwhile, the areas beyond Mars have had comparatively less focus. Asteroids and objects beyond Mars offer many new horizons for humanity to study. By using …
Gps-Derived Interseismic Fault Locking Along The Jalisco–Colima Segment Of The Mexico Subduction Zone, Beatriz Cosenza-Muralles, Charles Demets, B. Márquez-Azúa, O. Sánchez, J. Stock, Enrique Cabral-Cano, Robert Mccaffrey
Gps-Derived Interseismic Fault Locking Along The Jalisco–Colima Segment Of The Mexico Subduction Zone, Beatriz Cosenza-Muralles, Charles Demets, B. Márquez-Azúa, O. Sánchez, J. Stock, Enrique Cabral-Cano, Robert Mccaffrey
Geology Faculty Publications and Presentations
Northeastward subduction of the oceanic Rivera and Cocos plates in western Mexico poses a poorly understood seismic hazard to the overlying areas of the North America plate. We estimate the magnitude and distribution of interseismic locking along the northern ∼500 km of the Mexico subduction zone, with a series of elastic half-space inversions that optimize the fits to the velocities of 57 GPS stations in western Mexico. All velocities were corrected for the co-seismic, afterslip and viscoelastic rebound effects of the 1995 Colima–Jalisco and 2003 Tecomán earthquakes. We explore the robustness of interseismic locking estimates to a variety of mantle …
An Examination Of The Impacts Of Beaver Dam Mimicry Structures On Groundwater Surface-Water Interactions In Lower Mountain Riparian Systems, Mercedes D. Salazar
An Examination Of The Impacts Of Beaver Dam Mimicry Structures On Groundwater Surface-Water Interactions In Lower Mountain Riparian Systems, Mercedes D. Salazar
Graduate Theses & Non-Theses
Beaver dam analogs (BDAs) are a low cost, low disturbance stream restoration technique that may improve surface-water/groundwater interactions and wetland connectivity. BDAs are intended to imitate the effects of natural beaver dams by slowing stream velocity, promoting infiltration, increasing dry-season streamflow, aggrading the streambed, and capturing organic matter and other nutrients. This study was conducted to evaluate the degree to which these objectives were being met at a study site on Perkins Gulch, southwest Montana, USA. The Perkins Gulch study area can be summarized by four gauging sites that separate three reaches along the creek. By detailing background processes and …
Syllabus Geo101, Yuri Gorokhovich
Syllabus Geo101, Yuri Gorokhovich
Open Educational Resources
Syllabus for courses Dynamic Earth (undergraduate course): GEO 101-81 and Earth Processes (graduate course): GEO 501-81. Open textbook used in both courses linked in the syllabus and available at the following link: https://pressbooks.cuny.edu/gorokhovich/
The Mineralogy And Geochemistry Of Illinois Basin Paleosols: Recognizing Detrital, Pedogenic, And Diagenetic Minerals, Julia A. Mcintosh
The Mineralogy And Geochemistry Of Illinois Basin Paleosols: Recognizing Detrital, Pedogenic, And Diagenetic Minerals, Julia A. Mcintosh
Earth Sciences Theses and Dissertations
The geochemical compositions of minerals in paleosols are assumed to be homogenous and attained through chemical weathering processes during episodes of pedogenesis in the geologic past. As such, the geochemical composition of minerals from paleosols may be used to reconstruct ancient climates and environments. One problem with this assumption is that paleosols were initially clastic sedimentary rocks or substrate prior to pedogenesis, thus it is likely that some portion of the paleosol is still composed of detrital minerals. Secondly, conditions may change in a sedimentary basin as the basin is buried and later uplifted, potentially triggering new mineralization or transformation …
Cosmogenic Ages Indicate No Mis 2 Refugia In The Alexander Archipelago, Alaska, Caleb K. Walcott, Jason P. Briner, James F. Baichtal, Alia J. Lesnek, Joseph M. Licciardi
Cosmogenic Ages Indicate No Mis 2 Refugia In The Alexander Archipelago, Alaska, Caleb K. Walcott, Jason P. Briner, James F. Baichtal, Alia J. Lesnek, Joseph M. Licciardi
Publications and Research
The late-Pleistocene history of the coastal Cordilleran Ice Sheet remains relatively unstudied compared to chronologies of the Laurentide Ice Sheet. Yet accurate reconstructions of Cordilleran Ice Sheet extent and the timing of ice retreat along the Pacific Coast are essential for paleoclimate modeling, assessing meltwater contribution to the North Pacific, and determining the availability of ice-free land along the coastal Cordilleran Ice Sheet margin for human migration from Beringia into the rest of the Americas. To improve the chronology of Cordilleran Ice Sheet history in the Alexander Archipelago, Alaska, we applied 10Be and 36Cl dating to boulders and glacially sculpted …
In Situ Recording Of Mars Soundscape, S. Maurice, B. Chide, N. Murdoch, R. D. Lorenz, D. Mimoun, R. C. Wiens, Arya Udry, The Supercam Team
In Situ Recording Of Mars Soundscape, S. Maurice, B. Chide, N. Murdoch, R. D. Lorenz, D. Mimoun, R. C. Wiens, Arya Udry, The Supercam Team
Geoscience Faculty Research
Before the Perseverance rover landing, the acoustic environment of Mars was unknown. Models predicted that: (1) atmospheric turbulence changes at centimetre scales or smaller at the point where molecular viscosity converts kinetic energy into heat1, (2) the speed of sound varies at the surface with frequency2,3 and (3) high-frequency waves are strongly attenuated with distance in CO2 (refs. 2,3,4). However, theoretical models were uncertain because of a lack of experimental data at low pressure and the difficulty to characterize turbulence or attenuation in a closed environment. Here, using Perseverance microphone recordings, we present the first characterization of the acoustic environment …
Quantifying The Controls Of Shear-Coupled P-Waves, Jackson Saftner
Quantifying The Controls Of Shear-Coupled P-Waves, Jackson Saftner
Theses and Dissertations
Shear-coupled P-waves have been shown to possess great utility in resolving crustal and upper mantle models, however these phases remain largely untapped due to their ephemeral nature. Shear-coupled P-waves are a type of seismic phase that undergo S-to-P conversion either at the free-surface or at the base of the crust. Under the proper conditions, it is possible for the converted crustal P phases to achieve total internal reflection, allowing these phases to remain large in amplitude and sample long segments of the crust. In this study, we use a combination of real-world observations collected from literature, and synthetic seismograms, to …
Experimental Insights Into The Origin Of Microcrystalline Calcites, Mohammed Hashim
Experimental Insights Into The Origin Of Microcrystalline Calcites, Mohammed Hashim
Dissertations
A significant proportion of modern marine calcium carbonate sediments is dominated by metastable aragonite and high Mg calcite that either dissolves or stabilizes to low-Mg-calcite (calcite) or dolomite during diagenesis. Sediment dissolution and stabilization have implications for the CaCO3 budget in the ocean and carbon burial rates. Yet, the diagenetic conditions that promote each process and their relative importance are poorly understood. Further, stabilization most commonly produces calcite microcrystals that exhibit various textures and host micropores. Despite their ubiquity in the rock record, the controls on microcrystal textures remain unclear. Here, laboratory experiments were used to investigate aragonite-to-calcite stabilization as …
Assessment Of The Impact Of Climate Change On Stream Flow: The Case Of Little Ruaha Catchment, Rufiji Basin, Tanzania, Joel Nobert
Assessment Of The Impact Of Climate Change On Stream Flow: The Case Of Little Ruaha Catchment, Rufiji Basin, Tanzania, Joel Nobert
Tanzania Journal of Science
Little Ruaha catchment has been recognized for its potential to support multi-projects including irrigated schemes, urban water supply and providing significant inflow to Mtera reservoir for hydropower generation and ultimately Julius Nyerere Hydropower Plant (JNHPP). Despite the potential, the catchment has experienced declining flows in the recent years. This study assessed the likely changes in streamflow due to future climate change in the Little Ruaha catchment for the period 2025-2060. General Circulation Model (GCM) datasets from ACCESS1.0, CNRM-CM5 and BCC-CSM1 models and RCP4.5 and RCP8.5 greenhouse gas concentration scenarios were selected as the representative scenarios. Impact of climate change on …
Geology Online Lab Activities An Open Educational Resource For Community College Students And Instructors, Rondi Davies
Geology Online Lab Activities An Open Educational Resource For Community College Students And Instructors, Rondi Davies
Open Educational Resources
The online geology lab for community college students was developed by Dr. Rondi Davies, a faculty member at Queensborough Community College, City University New York, during two years of forced online synchronous learning brought on by the COVID-19 pandemic. This open educational resource collects many of Dr. Davies’ favorite open-access materials and supplements them with her own work within a single, cohesive laboratory manual intended for two-year, non-major college students from the New York area.
Dr. Davies wanted to develop labs that were fun, engaging, and that excited students about the subject, were relevant to their lives, helped them to …
Informing Management Of Henrys Lake, Idaho, Using An Integrated Catch-At-Age Model, Joshua L. Mccormick, Jennifer Vincent, Brett High, Darcy K. Mccarrick, Michael C. Quist
Informing Management Of Henrys Lake, Idaho, Using An Integrated Catch-At-Age Model, Joshua L. Mccormick, Jennifer Vincent, Brett High, Darcy K. Mccarrick, Michael C. Quist
United States Geological Survey: Staff Publications
Henrys Lake, Idaho, supports a popular fishery for Yellowstone Cutthroat Trout Oncorhynchus clarkii bouvieri and Yellowstone Cutthroat Trout × Rainbow Trout O. mykiss hybrids. A majority of the adult population of fish in Henrys Lake are of hatchery origin that were stocked as fingerlings. The fishery is closed to angling during the late winter and spring months, but fisheries managers are considering opening the fishery year-round with catch-and-release- only regulations or with a two-fish bag limit during the extended season. However, there is concern that the proposed management actions may negatively affect the current fishery. Therefore, we developed an integrated …
Rose Valley Rocks!: From Plate Tectonics To Architecture Of Place, Walter Cressler
Rose Valley Rocks!: From Plate Tectonics To Architecture Of Place, Walter Cressler
University Libraries Faculty Publications
No abstract provided.
Characterizing Explosive Volcanic Eruptions Using Tephra Fall Deposit Data, Robert Constantinescu
Characterizing Explosive Volcanic Eruptions Using Tephra Fall Deposit Data, Robert Constantinescu
USF Tampa Graduate Theses and Dissertations
This dissertation addresses the estimation of the magnitudes and intensities of explosive volcanic eruptions using tephra fall deposits and numerical modeling. Tephra fall deposits retain information about eruption dynamics. Volcanologists sample tephra fall deposits and measure the thickness, extent and grain size distribution to estimate the erupted volume and plume height of explosive eruptions. These terms are known as eruption source parameters. These parameters are used to classify the intensity and magnitude of the eruption on a scale such as the Volcanic Explosivity Index (VEI). Accurate estimation of the intensity and magnitude of explosive eruptions is a crucial factor in …
Serving Beijing 2022 Olympic Winter Games And Developing Ice And Snow Industry: Application And Extension Of Cryospheric Science, Dahe Qin, Cunde Xiao, Minghu Ding, Feiteng Wang, Zhiqiang Zhu, Shuiqing Yin, Jiawen Ren
Serving Beijing 2022 Olympic Winter Games And Developing Ice And Snow Industry: Application And Extension Of Cryospheric Science, Dahe Qin, Cunde Xiao, Minghu Ding, Feiteng Wang, Zhiqiang Zhu, Shuiqing Yin, Jiawen Ren
Bulletin of Chinese Academy of Sciences (Chinese Version)
Cryospheric Science, as an emerging interdisciplinary research field combining natural science and humanity, aims to understand nature's law, serve human society and promote sustainable development. In recent years, by deepening the understanding of the cryosphere elements and the whole sphere, and by expanding the application research of cryospheric science, the Chinese community of cryospheric science has developed by leaps and bounds and realized the crossover from the traditional basic research to serving the major national needs, which marks the increasing maturity of the discipline. The Beijing 2022 Olympic Winter Games is a major landmark event at an important historical time …
Potassic Volcanism Induced By Mantle Upwelling Through A Slab Window: Evidence From Shear Wave Splitting Analyses In Central Java, Fansheng Kong, Stephen S. Gao, Kelly H. Liu, Jiabiao Li
Potassic Volcanism Induced By Mantle Upwelling Through A Slab Window: Evidence From Shear Wave Splitting Analyses In Central Java, Fansheng Kong, Stephen S. Gao, Kelly H. Liu, Jiabiao Li
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
To delineate the mantle flow fields in the vicinity of a previously proposed slab window and the possible roles that they may play in the formation of potassic volcanism in Central Java, we conduct shear wave splitting analyses using both local S and teleseismic XKS waves (including SKS, SKKS, and PKS) recorded by 121 onshore stations and two ocean bottom seismometers (OBSs). The XKS fast orientations from the OBSs are trench normal and in accord with previous subslab anisotropy measurements. In the eastern part of Central Java, the XKS and local S fast orientations from the onshore stations are mostly …
Continental Break-Up Under A Convergent Setting: Insights From P Wave Radial Anisotropy Tomography Of The Woodlark Rift In Papua New Guinea, Youqiang Yu, Frederik Tilmann, Dapeng Zhao, Stephen S. Gao, Kelly H. Liu
Continental Break-Up Under A Convergent Setting: Insights From P Wave Radial Anisotropy Tomography Of The Woodlark Rift In Papua New Guinea, Youqiang Yu, Frederik Tilmann, Dapeng Zhao, Stephen S. Gao, Kelly H. Liu
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
To explore the dynamic mechanism of continental rifting within a convergent setting, we determine the first P wave radial anisotropic tomography beneath the Woodlark rift in southeastern Papua New Guinea, which develops within the obliquely colliding zone between the Australian and southwest Pacific plates. The rift zone is depicted as localized low-velocity anomalies with positive radial anisotropy, which rules out a dominant role of active mantle upwelling in promoting the rift development and favors passive rifting with decompression melting as main processes. Downwelling slab relics in the upper mantle bounding the rift zone are revealed based on observed high-velocity anomalies …
Arsenic In Groundwater Sources From Selected Communities Surrounding Taal Volcano, Philippines: An Exploratory Study, Geminn Louis C. Apostol, Sary Valenzuela, Xerxes Seposo
Arsenic In Groundwater Sources From Selected Communities Surrounding Taal Volcano, Philippines: An Exploratory Study, Geminn Louis C. Apostol, Sary Valenzuela, Xerxes Seposo
Ateneo School of Medicine and Public Health Publications
Arsenic (As) is a highly toxic, carcinogenic trace metal that can potentially contaminate groundwater sources in volcanic regions. This study provides the first comparative documentation of As concentrations in groundwater in a volcano-sedimentary region in the Philippines. Matched, repeated As measurements and physico-chemical analyses were performed in 26 individual wells from 11 municipalities and city in Batangas province from July 2020 to November 2021. Using the electrothermal atomic absorption spectrometric method, analysis of the wells revealed that in 2020, 23 out of 26 (88.46%) had As levels above the WHO limit of >10 ppb while 20 out of 26 wells …
Accuracy Assessment, Comparative Performance, And Enhancement Of Public Domain Digital Elevation Models (Aster 30 M, Srtm 30 M, Cartosat 30 M, Srtm 90 M, Merit 90 M, And Tandem-X 90 M) Using Dgps, Kumari Preety, Anup K. Prasad, Atul K. Varma, Hesham El-Askary
Accuracy Assessment, Comparative Performance, And Enhancement Of Public Domain Digital Elevation Models (Aster 30 M, Srtm 30 M, Cartosat 30 M, Srtm 90 M, Merit 90 M, And Tandem-X 90 M) Using Dgps, Kumari Preety, Anup K. Prasad, Atul K. Varma, Hesham El-Askary
Mathematics, Physics, and Computer Science Faculty Articles and Research
Publicly available Digital Elevation Models (DEM) derived from various space-based platforms (Satellite/Space Shuttle Endeavour) have had a tremendous impact on the quantification of landscape characteristics, and the related processes and products. The accuracy of elevation data from six major public domain satellite-derived Digital Elevation Models (a 30 m grid size—ASTER GDEM version 3 (Ast30), SRTM version 3 (Srt30), CartoDEM version V3R1 (Crt30)—and 90 m grid size—SRTM version 4.1 (Srt90), MERIT (MRT90), and TanDEM-X (TDX90)), as well as the improvement in accuracy achieved by applying a correction (linear fit) using Differential Global Positioning System (DGPS) estimates at Ground Control Points (GCPs) …
The Mechanics Of Initiation And Development Of Thrust Faults And Thrust Ramps, Sarah S. Wigginton, Elizabeth S. Petrie, James P. Evans
The Mechanics Of Initiation And Development Of Thrust Faults And Thrust Ramps, Sarah S. Wigginton, Elizabeth S. Petrie, James P. Evans
Geosciences Faculty Publications
This study integrates the results of numerical modeling analyses based on outcrop studies and structural kinematic restorations to evaluate the mechanics of thrust fault initiation and development in mechanically layered sedimentary rocks. A field-based reconstruction of a mesoscopic thrust fault at Ketobe Knob in central Utah provides evidence of thrust ramp nucleation in competent units, and fault propagation upward and downward into weaker units at both fault tips. We investigate the effects of mechanical stratigraphy on stress heterogeneity, rupture direction, fold formation, and fault geometry motivated by the geometry of the Ketobe Knob thrust fault in central Utah; the finite …
New Hampshire Continental Shelf Geospatial Database: Surficial Geology Maps And Sediment Grain Size Data, Larry G. Ward, Zachary S. Mcavoy, Rachel C. Morrison
New Hampshire Continental Shelf Geospatial Database: Surficial Geology Maps And Sediment Grain Size Data, Larry G. Ward, Zachary S. Mcavoy, Rachel C. Morrison
Data Catalog
The “New Hampshire Continental Shelf Geospatial Database: Surficial Geology Maps and Sediment Grain Size Data” consists of high-resolution surficial geology maps of the continental shelf off New Hampshire to Jeffreys Ledge in the Western Guff of Maine (WGOM) and supporting sediment grain size information. The surficial geology maps cover ~3,250 km2 (Figure 1). The maps depict three different classifications based on the Coastal and Marine Ecological Classification Standards (CMECS; FGDC, 2012): Geoforms (major morphologic or physiographic features; Figure 2; Table 1), Geologic Substrate Subclass (Figure 3; Table 2), and Geologic Substrate Group (Figure 4; Table 2). The maps are …
Prolonged Drying Trend Coincident With The Demise Of Norse Settlement In Southern Greenland, Boyang Zhao, Isla S. Castañeda, Jeffrey M. Salacup, Elizabeth K. Thomas, William C. Daniels, Tobias Schneider, Gregory A. De Wet, Raymond S. Bradley
Prolonged Drying Trend Coincident With The Demise Of Norse Settlement In Southern Greenland, Boyang Zhao, Isla S. Castañeda, Jeffrey M. Salacup, Elizabeth K. Thomas, William C. Daniels, Tobias Schneider, Gregory A. De Wet, Raymond S. Bradley
Geosciences: Faculty Publications
Declining temperature has been thought to explain the abandonment of Norse settlements, southern Greenland, in the early 15th century, although limited paleoclimate evidence is available from the inner settlement region itself. Here, we reconstruct the temperature and hydroclimate history from lake sediments at a site adjacent to a former Norse farm. We find no substantial temperature changes during the settlement period but rather that the region experienced a persistent drying trend, which peaked in the 16th century. Drier climate would have notably reduced grass production, which was essential for livestock overwintering, and this drying trend is concurrent with a Norse …
Soil Chemistry And Clay Mineralogy Of An Alluvial Chronosequence From The North Carolina Sandhills Of The Upper Coastal Plain, Usa, Bradley E. Suther, David S. Leigh, Larry T. West
Soil Chemistry And Clay Mineralogy Of An Alluvial Chronosequence From The North Carolina Sandhills Of The Upper Coastal Plain, Usa, Bradley E. Suther, David S. Leigh, Larry T. West
Faculty Articles
Temporal changes in soil development were assessed on fluvial terraces of the Little River in the upper Coastal Plain of North Carolina. We examined five profiles from each of six surfaces spanning about 100,000 years. Soil-age relationships were evaluated with inter-surface clay mineral comparisons and regression of chemical properties versus previously reported optically-stimulated luminescence ages using the most developed subsoil horizon per profile. Bases to alumina (Bases/Al2 O3 ) ratios have negative correlations with age, whereas dithionite-Fe (FeD ) concentrations are positively correlated with time and differentiate floodplain (BP) from terrace (≥10 ± 2 ka) soils and T4 pedons (75 …
Co-Seismic And Post-Seismic Deformation For The 1995 Colima–Jalisco And 2003 Tecoman Thrust Earthquakes, Mexico Subduction Zone, ́ From Modelling Of Gps Data, Beatriz Cosenza-Muralles, Charles Demets, O. Sanchez, Enrique Cabral-Cano, J. Stock, B. Márquez-Azúa, Robert Mccaffrey
Co-Seismic And Post-Seismic Deformation For The 1995 Colima–Jalisco And 2003 Tecoman Thrust Earthquakes, Mexico Subduction Zone, ́ From Modelling Of Gps Data, Beatriz Cosenza-Muralles, Charles Demets, O. Sanchez, Enrique Cabral-Cano, J. Stock, B. Márquez-Azúa, Robert Mccaffrey
Geology Faculty Publications and Presentations
We invert ∼25 yr of campaign and continuous Global Positioning System daily positions at 62 sites in southwestern Mexico to estimate co-seismic and post-seismic afterslip solutions for the 1995 Mw = 8.0 Colima–Jalisco and the 2003 Mw = 7.5 Tecomán earthquakes, and the long-term velocity of each GPS site. Estimates of the viscoelastic effects of both earthquakes from a 3-D model with an elastic crust and subducting slab, and linear Maxwell viscoelastic mantle are used to correct the GPS position time-series prior to our time-dependent inversions. The preferred model, which optimizes the fit to data from several years …
Toward The Understanding Of The 2018 Arnold, Ne Earthquake Cluster: Relocation Of Hypocenters And Establishment Of New Gravity Base Stations, Kris Guthrie
Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research
In 2018, 27 unexpected earthquakes occurred in central Nebraska near Arnold. These earthquakes have no readily apparent cause and no evidence of the responsible fault system is seen at the surface. A joint analysis of vintage, regional gravity and magnetic datasets before the first earthquake revealed a lineament that could represent a pre-existing fault system. New high resolution potential fields data are needed to confidently map the subsurface features around the cluster. To design a survey and collect the data, the following tasks need to be addressed: [1] The earthquakes’ hypocenters need to be improved (relocated) to increase the efficiency …
Nebraska Statewide Groundwater-Level Monitoring Report 2021, Aaron R. Young, Mark E. Burbach, Leslie M. Howard, Sue Olafsen Lackey, Robert Matthew Joeckel
Nebraska Statewide Groundwater-Level Monitoring Report 2021, Aaron R. Young, Mark E. Burbach, Leslie M. Howard, Sue Olafsen Lackey, Robert Matthew Joeckel
Conservation and Survey Division: Faculty and Staff Publications
This report is a synthesis of groundwater-level monitoring programs in Nebraska. It is a continuation of the series of annual reports and maps produced by the Conservation and Survey Division (CSD) of the University of Nebraska in cooperation with the U.S. Geological Survey (USGS) since the 1950s. Groundwater-level monitoring began in Nebraska in 1930 in an effort to survey the state’s groundwater resources and to observe changes in its availability on a continuing basis. The CSD and USGS cooperatively developed, maintained, and operated an observation-well network throughout the state. These two agencies were responsible for collecting and archiving this information, …
Contrasting Styles Of Inter-Caldera Volcanism In A Peralkaline System: Case Studies From Pantelleria (Sicily Channel, Italy), Pierangelo Romano, John C. White, Silvio G. Rotolo, Nina J. Jordan, Rosolino Cirrincione, Giovanni De Giorgio, Patrizia Fiannacca, Epifanio Vaccaro
Contrasting Styles Of Inter-Caldera Volcanism In A Peralkaline System: Case Studies From Pantelleria (Sicily Channel, Italy), Pierangelo Romano, John C. White, Silvio G. Rotolo, Nina J. Jordan, Rosolino Cirrincione, Giovanni De Giorgio, Patrizia Fiannacca, Epifanio Vaccaro
EKU Faculty and Staff Scholarship
The recent (<190 ka) volcanic history of Pantelleria is characterized by the eruption of nine peralkaline ignimbrites, ranging in composition from comenditic trachyte to comendite to pantellerite. The ~46 ka Green Tuff (GT) was the last of these ignimbrites, which was followed by many effusive and explosive low-volume eruptions of pantellerite from vents within the caldera moat and along the caldera rim. Although recent studies have shed additional light on the age, petrochemistry, and volcanology of the older ignimbrites, there is very little knowledge of magmatism that occurred between these older ignimbrites, primarily due to the very scarce exposures. In this paper, we present new field descriptions and geochemical data for three local peralkaline centers never studied before, two pre-GT and one post-GT, which share a similar setting with respect to the caldera scarps but differ in terms of their age, composition, and eruptive style. These centers include: (i) the older (~125 ka) Giache center (comenditic trachyte), (ii) the ~67 ka Attalora center (comendite, pantellerite), and (iii) the younger (~14 ka) Patite center (pantellerite).
Paradigm Versus Paradox On The Prairie: Testing Competing Stream Fish Movement Frameworks Using An Imperiled Great Plains Minnow, Zachary D. Steffensmeier, Maeghen Wedgeworth, Lauren Yancy, Noah Santee, Shannon K. Brewer, Joshuah S. Perkin
Paradigm Versus Paradox On The Prairie: Testing Competing Stream Fish Movement Frameworks Using An Imperiled Great Plains Minnow, Zachary D. Steffensmeier, Maeghen Wedgeworth, Lauren Yancy, Noah Santee, Shannon K. Brewer, Joshuah S. Perkin
United States Geological Survey: Staff Publications
Background: Movement information can improve conservation of imperiled species, yet movement is not quantified for many organisms in need of conservation. Prairie chub (Macrhybopsis australis) is a regionally endemic freshwater fish with unquantified movement ecology and currently considered for listing under the Endangered Species Act. The purpose of this study was to test competing ecological theories for prairie chub movement, including the colonization cycle hypothesis (CCH) that posits adults must make upstream movements to compensate for downstream drift at early life stages, and the restricted movement paradigm (RMP) that describes populations as heterogeneous mixes of mostly stationary …