Feasibility Assessment On Use Of Proximal Geophysical Sensors To Support Precision Management,
2022
University of Nebraska-Lincoln
Feasibility Assessment On Use Of Proximal Geophysical Sensors To Support Precision Management, Sophia M. Becker
Dissertations & Theses in Natural Resources
Soil property maps provide information for field management activities such as irrigation, fertilization, and seeding. Many on-the-go proximal geophysical sensors have been developed in recent decades that can help map agricultural fields without dense soil sampling. To utilize these technologies most profitably in precision management, scientists and precision agriculture dealers must better understand sensors’ performances in given field conditions and the economic value of different proximal soil sensing methods. Chapter two reports the study that was conducted at three sites in North Dakota, United States to strengthen understanding of the usefulness of different proximal geophysical data types in agricultural contexts …
Computational Approaches To Understanding Subduction Zone Geodynamics, Surface Heat Flow, And The Metamorphic Rock Record,
2022
Boise State University
Computational Approaches To Understanding Subduction Zone Geodynamics, Surface Heat Flow, And The Metamorphic Rock Record, Buchanan C. Kerswell
Boise State University Theses and Dissertations
Pressure-temperature (PT) estimates from exhumed high-pressure (HP) metamorphic rocks and global surface heat flow observations evidently encode information about subduction zone thermal structure and the nature of mechanical and chemical processing of subducted materials along the interface between converging plates. Previous work demonstrates the possibility of decoding such geodynamic information by comparing numerical geodynamic models with empirical observations of surface heat flow and the metamorphic rock record. However, ambiguous interpretations can arise from this line of inquiry with respect to thermal gradients, plate coupling, and detachment and recovery of subducted materials. This dissertation applies a variety of computational techniques to …
Characterization And Evolution Of The Professor Valley Pennsylvanian Salt Body (Paradox Basin, Ut) Using Gravity And Magnetotellurics,
2022
The University of Texas at El Paso
Characterization And Evolution Of The Professor Valley Pennsylvanian Salt Body (Paradox Basin, Ut) Using Gravity And Magnetotellurics, Derek Scott
Open Access Theses & Dissertations
Syndepositional halokinetic movement of the Pennsylvanian Paradox Formation in the Paradox Basin, UT & CO behaved as a control over the development of depositional systems during the Late Paleozoic and early Mesozoic periods (Trudgill, 2011). Understanding the controls on halokinetic evolution in the area serves as an invaluable outcrop analogue for similar subsurface salt bodies in petroleum-bearing basins and provides key insights for hydrocarbon exploration in salt basins world wide. Professor Valley, located 15 miles Northeast of Moab, UT is situated between the Fisher Valley (Onion Creek) and Cache/Salt Valley salt walls. It includes an anomalous, isolated 0.5 km² outcrop …
Volcano Infrasound: Progress And Future Directions,
2022
Boise State University
Volcano Infrasound: Progress And Future Directions, Jacob F. Anderson, Jeffrey B. Johnson
Geosciences Faculty Publications and Presentations
Over the past two decades (2000–2020), volcano infrasound (acoustic waves with frequencies less than 20 Hz propagating in the atmosphere) has evolved from an area of academic research to a useful monitoring tool. As a result, infrasound is routinely used by volcano observatories around the world to detect, locate, and characterize volcanic activity. It is particularly useful in confirming subaerial activity and monitoring remote eruptions, and it has shown promise in forecasting paroxysmal activity at open-vent systems. Fundamental research on volcano infrasound is providing substantial new insights on eruption dynamics and volcanic processes and will continue to do so over …
Comparing Satellite Vs Marine Potential Fields Data Over The Bathymetrists Seamounts,
2022
University of Nebraska - Lincoln
Comparing Satellite Vs Marine Potential Fields Data Over The Bathymetrists Seamounts, Alexa Fernandez, Irina Filina
UNL Student Research Days Posters, Graduate
The Bathymetrists Seamounts (BSM) are located north of the Sierra Leone Rise (SLR) in the mid-Atlantic Ocean. The seamounts reside on oceanic crust that is 105 to 45 million years old. However, dredging over the Bathymetrists Seamounts dated rocks at ~40 Myr. The general trend of the seamounts contradicts the eastward motion of the African tectonic plate. The origin and tectonic history of the Bathymetrists Seamounts remains debated in literature. Potential fields (gravity and magnetic) data can provide important insight into the formation and evolution of the seamounts. The purpose of this study is to compare available gravity and magnetic …
Processing Seismic, Gravity And Magnetic Data Over Diebold
Knoll On Juan De Fuca Plate,
2022
University of Nebraska-Lincoln
Processing Seismic, Gravity And Magnetic Data Over Diebold Knoll On Juan De Fuca Plate, Md Ariful Islam, Irina Filina
UNL Student Research Days Posters, Graduate
The Juan de Fuca plate is subducting beneath the North American plate along the Cascadia Subduction Zone. The CSZ is associated with multiple earthquakes, although compared to other subduction zones, it is less active. Many studies suggest that subduction will cause major mega thrust earthquake in near future, while others oppose this view. This project is focused on the Diebold Knoll on the JdF plate Various geophysical methods will be integrated to determine its origin and tectonic history.
A Robust Age Model For The Cryogenian Pocatello Formation Of Southeastern Idaho (Northwestern Usa) From Tandem In Situ And Isotope Dilution U-Pb Dating Of Volcanic Tuffs And Epiclastic Detrital Zircons,
2022
Boise State University
A Robust Age Model For The Cryogenian Pocatello Formation Of Southeastern Idaho (Northwestern Usa) From Tandem In Situ And Isotope Dilution U-Pb Dating Of Volcanic Tuffs And Epiclastic Detrital Zircons, Vincent H. Isakson, Mark D. Schmitz, Carol M. Dehler, Francis A. Macdonald, W. Adolph Yankee
Geosciences Faculty Publications and Presentations
Tandem in situ and isotope dilution U-Pb analysis of zircons from pyroclastic volcanic rocks and both glacial and non-glacial sedimentary strata of the Pocatello Formation (Idaho, northwestern USA) provides new age constraints on Cryogenian glaciation in the North American Cordillera. Two dacitic tuffs sampled within glacigenic strata of the lower diamictite interval of the Scout Mountain Member yield high-precision chemical abrasion isotope dilution U-Pb zircon eruption and depositional ages of 696.43 ± 0.21 and 695.17 ± 0.20 Ma. When supplemented by a new high-precision detrital zircon maximum depositional age of ≤ 670 Ma for shoreface and offshore sandstones unconformably overlying …
Systematic Integration Of Applications Into The Surface Biology And Geology (Sbg) Earth Mission Architecture Study,
2022
California Institute of Technology
Systematic Integration Of Applications Into The Surface Biology And Geology (Sbg) Earth Mission Architecture Study, Christine M. Lee, Nancy F. Glenn, E. Natasha Stavros, Jeff Luvall, Karen Yuen, Stephanie Schollaert Uz
Geosciences Faculty Publications and Presentations
The Surface Biology and Geology (SBG) concept is the first National Aeronautics and Space Administration (NASA) Earth mission to develop and implement systematic integration of science application needs at the architecture study stage. Prior NASA mission concept and planning activities presumed that science measurement needs would encompasss application measurement needs and so did not explicitly evaluate and include applications at this stage. However, the effort presented here identified, documented and integrated application needs that would not have been included by considering research science needs only. First, a low latency of no greater than 24 hr was identified as the optimal …
Testing Aftershock Forecasts Using Bayesian Methods,
2022
The University of Western Ontario
Testing Aftershock Forecasts Using Bayesian Methods, Elisa Dong
Electronic Thesis and Dissertation Repository
The presence of strong aftershocks can increase the seismic hazard following a large earthquake and should be considered for operational earthquake forecasting and risk management. Aftershock forecasts are generated from seismicity models during the evolution of the aftershock sequence. This work compares quantitative test results of the forecasting abilities for three competing aftershock rate models - the modified Omori law, the Epidemic Type Aftershock Sequence model, and the compound Omori law - to identify the best performing model for forecasting the largest aftershock during the early aftershock sequence. Forecasts of large aftershock probabilities are generated by either the Extreme Value …
Observations On The Stress Related Variations Of Soil Radon Concentration In The Gulf Of Corinth, Greece,
2022
National Observatory of Athens
Observations On The Stress Related Variations Of Soil Radon Concentration In The Gulf Of Corinth, Greece, Vassilios K. Karastathis, George Eleftheriou, Menas Kafatos, Kanaris Tsinganos, G-Akis Tselentis, Evangelos Mouzakiotis, Dimitar Ouzounov
Mathematics, Physics, and Computer Science Faculty Articles and Research
Our observations indicate a characteristic pattern in the long-term variation of soil radon concentrations, which seems to be consistent with the expected variation of regional stress in relation to seismicity. However, it seems that the major changes in radon level begin before the rock rapture, i.e. before the earthquake occurs. These conclusions have emerged after long-term observations with continuous and thorough real-time gamma-radiation monitoring in the seismically active area of the Gulf of Corinth, Greece. The recordings acquired close to a hot spring were of very high quality, implying that the deep hydraulic flow can possibly play a key role …
Potassic Volcanism Induced By Mantle Upwelling Through A Slab Window: Evidence From Shear Wave Splitting Analyses In Central Java,
2022
Missouri University of Science and Technology
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,
2022
Missouri University of Science and Technology
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 …
Simulation Of Infrasonic Acoustic Wave Imprints On Airglow Layers During The 2016 M7.8 Kaikoura Earthquake,
2022
Embry-Riddle Aeronautical University
Simulation Of Infrasonic Acoustic Wave Imprints On Airglow Layers During The 2016 M7.8 Kaikoura Earthquake, P. A. Inchin, J. Aguilar Guerrero, J. B. Snively, Y. Kaneko
Publications
Simulations of hypothesized but unobserved mesopause airglow (MA) disturbances generated by infrasonic acoustic waves (IAWs) during the 2016 M7.8 Kaikoura earthquake are performed. Realistic surface displacements are calculated in a forward seismic wave propagation model and incorporated into a 3-D nonlinear compressible neutral atmosphere model as a source of IAWs at the surface-air interface. Inchin et al. (2021), https://doi.org/10.1029/2020av000260 previously showed that Global Positioning System-based total electron content (TEC) observations can be used to constrain the finite-fault kinematics of the Kaikoura earthquake. However, due to limitations of Global Navigation Satellite System network coverage and coalescence of nonlinear IAW fronts, they …
Toward The Understanding Of The 2018 Arnold, Ne Earthquake Cluster: Relocation Of Hypocenters And Establishment Of New Gravity Base Stations,
2022
University of Nebraska-Lincoln
Toward The Understanding Of The 2018 Arnold, Ne Earthquake Cluster: Relocation Of Hypocenters And Establishment Of New Gravity Base Stations, Kris Guthrie
Dissertations & Theses in Earth and Atmospheric Sciences
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 …
Electron-Positron Annihilation Lifetime Spectroscopy Of Mgo And Aluminum-Doped Mgo,
2022
Union College - Schenectady, NY
Electron-Positron Annihilation Lifetime Spectroscopy Of Mgo And Aluminum-Doped Mgo, Elise Liebow
Honors Theses
Radiation is a form of energy that can damage materials at an atomic level. This has implications for the mobility of radioactive waste through containment materials. We are characterizing atomic defects in materials by using Electron-Positron Annihilation Lifetime Spectroscopy (EPALS). When an electron and positron come into contact with each other, they annihilate and release two antiparallel 511-keV gamma rays. In a pristine crystalline sample, positrons can easily annihilate with electrons, but in a sample with vacancies/defects in the crystal structure, positrons take longer to annihilate. Therefore, the more vacancies in a sample, the longer the average lifetime of a …
Developing A Soil Column System To Measure Hydrogeophysical Properties Of Unconsolidated Sediment,
2022
Boise State University
Developing A Soil Column System To Measure Hydrogeophysical Properties Of Unconsolidated Sediment, Taylor Bienvenue, Jing Xie, Qifei Niu
Geosciences Faculty Publications and Presentations
Geophysical methods have been increasingly used to characterize the Earth's critical zone (CZ) and monitor hydrological processes occurring within it. For a quantitative interpretation, geophysical studies of CZ materials are necessary, and thus require more sophisticated laboratory setups. In this study, we develop a hydrogeophysical soil column system to measure key hydraulic and electrical properties of regolith in CZs. The developed soil column system consists of two components: (a) a novel hydrogeophysical probe that measures pore water pressure and electrical potential in soils and (b) a cylindrical cell to hold soil samples. The system can be arranged to perform both …
Evidence For Short Temporal Atmospheric Variations Observed By Infrasonic Signals: 1. The Troposphere,
2022
Southern Methodist University
Evidence For Short Temporal Atmospheric Variations Observed By Infrasonic Signals: 1. The Troposphere, G. Averbuch, M. Ronac-Giannone, S. Arrowsmith, J. F. Anderson
Geosciences Faculty Publications and Presentations
Infrasound monitoring is used in the forensic analysis of events, studying the physical processes of sources of interest, and probing the atmosphere. The dynamical nature of the atmosphere and the use of infrasound as a forensic tool lead to the following questions; (1) what is the timescale of atmospheric variability that affects infrasonic signals? (2) how do infrasound signals vary as a function of time? This study addresses these questions by monitoring a repetitive infrasound source and its corresponding tropospheric returns 54 km away. Source-receiver empirical Green's functions are obtained every 20 s and used to demonstrate the effect of …
Prediction Of Soil Water Content And Electrical Conductivity Using Random Forest Methods With Uav Multispectral And Ground-Coupled Geophysical Data,
2022
Missouri University of Science and Technology
Prediction Of Soil Water Content And Electrical Conductivity Using Random Forest Methods With Uav Multispectral And Ground-Coupled Geophysical Data, Yunyi Guan, Katherine R. Grote, Joel Schott, Kelsi Leverett
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
The volumetric water content (VWC) of soil is a critical parameter in agriculture, as VWC strongly influences crop yield, provides nutrients to plants, and maintains the microbes that are needed for the biological health of the soil. Measuring VWC is difficult, as it is spatially and tempo-rally heterogeneous, and most agricultural producers use point measurements that cannot fully capture this parameter. Electrical conductivity (EC) is another soil parameter that is useful in agricul-ture, since it can be used to indicate soil salinity, soil texture, and plant nutrient availability. Soil EC is also very heterogeneous; measuring EC using conventional soil sampling …
Analysis Of Skills Sought By Employers Of Bachelors-Level Geoscientists,
2022
Boise State University
Analysis Of Skills Sought By Employers Of Bachelors-Level Geoscientists, Gregory Shafer, Karen Viskupic, Anne E. Egger
Geosciences Faculty Publications and Presentations
Bachelors-level geoscientists make up the majority of the geoscience workforce, and positions for entry-level geoscientists are expected to grow rapidly over the next decade, with some jobs anticipating upward of 10% growth (National Center for O*NET Development, 2021). Are geoscience departments adequately preparing undergraduate students to succeed in these positions?
Late Triassic To Jurassic Magmatic And Tectonic Evolution Of The Intermontane Terranes In Yukon, Northern Canadian Cordillera: Transition From Arc To Syn-Collisional Magmatism And Post-Collisional Lithospheric Delamination,
2022
Yukon Geological Survey
Late Triassic To Jurassic Magmatic And Tectonic Evolution Of The Intermontane Terranes In Yukon, Northern Canadian Cordillera: Transition From Arc To Syn-Collisional Magmatism And Post-Collisional Lithospheric Delamination, Maurice Colpron, Patrick J. Sack, James L. Crowley, Luke P. Beranek, Murray M. Allan
Geosciences Faculty Publications and Presentations
End-on arc collision and onset of the northern Cordilleran orogen is recorded in Late Triassic to Jurassic plutons in the Intermontane terranes of Yukon, and in development of the synorogenic Whitehorse trough (WT). A synthesis of the extensive data set for these plutons supports interpretation of the magmatic and tectonic evolution of the northern Intermontane terranes. Late Triassic juvenile plutons that locally intrude the Yukon-Tanana terrane represent the northern extension of arc magmatism within Stikinia. Early Jurassic plutons that intrude Stikinia and Yukon-Tanana terranes were emplaced during crustal thickening (200–195 Ma) and subsequent exhumation (190–178 Ma). The syn-collisional magmatism migrated …
