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Spatially Extensive Ground‐Penetrating Radar Snow Depth Observations During Nasa's 2017 Snowex Campaign: Comparison With In Situ, Airborne, And Satellite Observations, Hans-Peter Marshall 2021 Boise State University

Spatially Extensive Ground‐Penetrating Radar Snow Depth Observations During Nasa's 2017 Snowex Campaign: Comparison With In Situ, Airborne, And Satellite Observations, Hans-Peter Marshall

Geosciences Faculty Publications and Presentations

Seasonal snow is an important component of Earth's hydrologic cycle and climate system, yet it remains challenging to consistently and accurately measure snow depth and snow water equivalent (SWE) across the range of diverse snowpack conditions that exist on Earth. The NASA SnowEx campaign is focused on addressing the primary gaps in snow remote sensing in order to gain an improved spatiotemporal understanding of this important resource and to further efforts toward a future satellite‐based snow remote sensing mission. Ground‐penetrating radar (GPR) is an efficient and mature approach for measuring snow depth and SWE. We collected ~1 ...


Spectral Ground Motion Characteristics Of Induced Earthquakes In The Fort Worth Basin, Texas, SeongJu Jeong 2021 Southern Methodist University

Spectral Ground Motion Characteristics Of Induced Earthquakes In The Fort Worth Basin, Texas, Seongju Jeong

Earth Sciences Theses and Dissertations

Concurrent with the development of unconventional oil and gas production, seismicity in the central United States has dramatically increased. Previous studies in many locations suggest that the earthquakes reactivate pre-existing faults, as a result of changing subsurface stresses due to injection of fluids from wastewater disposal wells. This sudden rise in seismicity rate motivates an assessment and possible mitigation of seismic hazard due to the proximity of induced seismicity to metropolitan areas like the Dallas-Fort Worth, Texas.

Successful assessment and mitigation of earthquake hazards requires estimates of ground motion parameters representing path attenuation, site effects and source characteristics constrained by ...


Enhancing Infrasonic Signal Detection And Event Localization Through Advanced Computational Methods, Fransiska Dannemann Dugick 2021 Southern Methodist University

Enhancing Infrasonic Signal Detection And Event Localization Through Advanced Computational Methods, Fransiska Dannemann Dugick

Earth Sciences Theses and Dissertations

The installation of worldwide infrasound and seismo-acoustic networks at both global and regional scales necessitates automated techniques and algorithms for accurate and efficient data processing and analysis. Signals recorded across the networks originate from a number of natural and anthropogenic sources. Data processing efforts focus on the separation of signals of interest from background noise, followed by the identification, or detection of signals of interest. Once signals are identified, association and location processing produces estimates of a signal's source. This dissertation focuses on the evaluation of automated processes for identifying and locating sources of interest.

Chapter two applies two ...


Characterization Of Landslide Processes From Radar Remote Sensing And Hydromechanical Modeling, Yuankun Xu 2021 Southern Methodist University

Characterization Of Landslide Processes From Radar Remote Sensing And Hydromechanical Modeling, Yuankun Xu

Earth Sciences Theses and Dissertations

Landsides are a natural geomorphic process yet a dangerous hazard which annually causes thousands of casualties and billions of property loss in a global scale. Understanding landslide motion kinematics from early initiation to final deposition is critical for monitoring, assessing, and forecasting landslide movement in order to mitigate their hazards. Landslides occur under diverse environmental settings and appear in variable types; however, all types of landslides can be mechanically attributed to shearing failure at the basal surface due to stress regime shift contributed by internal and/or external forcing. Typical internal factors include soil/rock weathering, whereas typical external triggering ...


Nasa's Surface Biology And Geology Designated Observable: A Perspective On Surface Imaging Algorithms, Nancy F. Glenn 2021 Boise State University

Nasa's Surface Biology And Geology Designated Observable: A Perspective On Surface Imaging Algorithms, Nancy F. Glenn

Geosciences Faculty Publications and Presentations

The 2017–2027 National Academies' Decadal Survey, Thriving on Our Changing Planet, recommended Surface Biology and Geology (SBG) as a “Designated Targeted Observable” (DO). The SBG DO is based on the need for capabilities to acquire global, high spatial resolution, visible to shortwave infrared (VSWIR; 380–2500 nm; ~30 m pixel resolution) hyperspectral (imaging spectroscopy) and multispectral midwave and thermal infrared (MWIR: 3–5 μm; TIR: 8–12 μm; ~60 m pixel resolution) measurements with sub-monthly temporal revisits over terrestrial, freshwater, and coastal marine habitats. To address the various mission design needs, an SBG Algorithms Working Group of multidisciplinary researchers ...


Soil Inhomogeneity Effects On Seismic Wind Noise, Bipin Koirala 2021 University of Mississippi

Soil Inhomogeneity Effects On Seismic Wind Noise, Bipin Koirala

Honors Theses

Wind causes local pressure fluctuations over the ground. The pressure waves couples with the ground and transmits into the ground as seismic waves. The seismic wave, in turn, causes ground motion. Naderyan et al. [9] developed a prediction of the ground displacements spectra from the measured ground properties and predicted pressure and shear stress at the ground surface. Naderyan modeled the ground as a linearly elastic half space bounded by an infinite plane on one side. The quasi-static model for predicting displacement components in the ground is effective for the vertical component of the displacement response, but the model significantly ...


Co-Evolution Of Xylem Water And Soil Water Stable Isotopic Composition In A Northern Mixed Forest Biome, Jenna R. Snelgrove, James M. Buttle, Matthew J. Kohn, Dörthe Tetzlaff 2021 Trent University

Co-Evolution Of Xylem Water And Soil Water Stable Isotopic Composition In A Northern Mixed Forest Biome, Jenna R. Snelgrove, James M. Buttle, Matthew J. Kohn, Dörthe Tetzlaff

Geosciences Faculty Publications and Presentations

Plant–soil water isotopic dynamics in northern forests have been understudied relative to other forest types; nevertheless, such information can provide insight into how such forests may respond to hydroclimatic change. This study examines the co-evolution of xylem water and soil water stable isotopic compositions in a northern mixed forest in Ontario, Canada. Gross precipitation, bulk soil water and xylem water were sampled from pre-leaf out to post-senescence in 2016 for eastern white cedar, eastern hemlock, red oak and eastern white pine. Near-bole soil water contents and mobile soil water isotopic compositions were measured for the last three species. Mobile ...


Seismic Characteristics Of The Eastern North American Crust And Upper Mantle: The Formation And Evolution Of Continental Lithosphere, Cong Li 2021 University of Massachusetts Amherst

Seismic Characteristics Of The Eastern North American Crust And Upper Mantle: The Formation And Evolution Of Continental Lithosphere, Cong Li

Doctoral Dissertations

The impact of past tectonic events on formation and modification of continental lithosphere over the course of Earth’s history remains as an open question of fundamental importance. Physical properties of continental crust and mantle lithosphere, such as their age, thickness, composition, temperature, and velocity, contain crucial information for informing this question. Eastern North America provides at least two complete records of supercontinent assembly and breakup over the past 1.3 Ga, serving as a natural laboratory for our understanding of continental lithosphere evolution and for integrating geologic and geophysical observations. In this thesis, I have investigated the seismic properties ...


Reconstruction Of Historical Surface Mass Balance, 1984–2017 From Greentraacs Multi-Offset Ground-Penetrating Radar, Tate G. Meehan, H.P. Marshall 2021 Boise State University

Reconstruction Of Historical Surface Mass Balance, 1984–2017 From Greentraacs Multi-Offset Ground-Penetrating Radar, Tate G. Meehan, H.P. Marshall

Geosciences Faculty Publications and Presentations

We present continuous estimates of snow and firn density, layer depth and accumulation from a multi-channel, multi-offset, ground-penetrating radar traverse. Our method uses the electromagnetic velocity, estimated from waveform travel-times measured at common-midpoints between sources and receivers. Previously, common-midpoint radar experiments on ice sheets have been limited to point observations. We completed radar velocity analysis in the upper ∼2 m to estimate the surface and average snow density of the Greenland Ice Sheet. We parameterized the Herron and Langway (1980) firn density and age model using the radar-derived snow density, radar-derived surface mass balance (2015–2017) and reanalysis-derived temperature data ...


Understanding The Effect Of Fire On Vegetation Composition And Gross Primary Production In A Semi-Arid Shrubland Ecosystem Using The Ecosystem Demography (Edv2.2) Model, Karun Pandit, Hamid Dashti, Andrew T. Hudak, Nancy F. Glenn, Alejandro N. Flores 2021 University of Florida

Understanding The Effect Of Fire On Vegetation Composition And Gross Primary Production In A Semi-Arid Shrubland Ecosystem Using The Ecosystem Demography (Edv2.2) Model, Karun Pandit, Hamid Dashti, Andrew T. Hudak, Nancy F. Glenn, Alejandro N. Flores

Geosciences Faculty Publications and Presentations

Wildfires in sagebrush (Artemisia spp.)-dominated semi-arid ecosystems in the western United States have increased dramatically in frequency and severity in the last few decades. Severe wildfires often lead to the loss of native sagebrush communities and change the biogeochemical conditions which make it difficult for sagebrush to regenerate. Invasion of cheatgrass (Bromus tectorum) accentuates the problem by making the ecosystem more susceptible to frequent burns. Managers have implemented several techniques to cope with the cheatgrass–fire cycle, ranging from controlling undesirable fire effects by removing fuel loads either mechanically or via prescribed burns to seeding the fire-affected areas with ...


From Hector Mine M7.1 To Ridgecrest M7.1 Earthquake. A Look From A 20-Year Perspective, Sergey Pulinets, Marina Tsidilina, Dimitar Ouzounov, Dmitry Davidenko 2021 Russian Academy of Sciences

From Hector Mine M7.1 To Ridgecrest M7.1 Earthquake. A Look From A 20-Year Perspective, Sergey Pulinets, Marina Tsidilina, Dimitar Ouzounov, Dmitry Davidenko

Mathematics, Physics, and Computer Science Faculty Articles and Research

The paper provides a comparative analysis of precursory phenomena in the ionosphere and atmosphere for two strong earthquakes of the same magnitude M7.1 that happened in the same region (North-East from Los Angeles) within a time span of 20 years, the Hector Mine and Ridgecrest earthquakes. Regardless of the similarity of their location (South-Eastern California, near 160 km one from another), there was one essential difference: the Hector Mine earthquake happened during geomagnetically disturbed conditions (essential in the sense of ionospheric precursors identification). In contrast, the quiet geomagnetic conditions characterized the period around the time of the Ridgecrest earthquake ...


Snow Ensemble Uncertainty Project (Seup): Quantification Of Snow Water Equivalent Uncertainty Across North America Via Ensemble Land Surface Modeling, Hans-Peter Marshall 2021 Boise State University

Snow Ensemble Uncertainty Project (Seup): Quantification Of Snow Water Equivalent Uncertainty Across North America Via Ensemble Land Surface Modeling, Hans-Peter Marshall

Geosciences Faculty Publications and Presentations

The Snow Ensemble Uncertainty Project (SEUP) is an effort to establish a baseline characterization of snow water equivalent (SWE) uncertainty across North America with the goal of informing global snow observational needs. An ensemble-based modeling approach, encompassing a suite of current operational models is used to assess the uncertainty in SWE and total snow storage (SWS) estimation over North America during the 2009–2017 period. The highest modeled SWE uncertainty is observed in mountainous regions, likely due to the relatively deep snow, forcing uncertainties, and variability between the different models in resolving the snow processes over complex terrain. This highlights ...


Ps Series, Pingxin Xia, Longtan Shao, Wen Deng 2021 Missouri University of Science and Technology

Ps Series, Pingxin Xia, Longtan Shao, Wen Deng

Stress-State Dependency of the Deformation Ratio of Quasi-Elastic Granular Soils under Cyclic Loading -- Raw Data

‘PS’ and ‘PF’ spreadsheets are the data of the prediction and calibration tests. (The data in this series are overall stress and strain information).

Supporting information


Pf7, Pingxin Xia, Longtan Shao, Wen Deng 2021 Missouri University of Science and Technology

Pf7, Pingxin Xia, Longtan Shao, Wen Deng

Stress-State Dependency of the Deformation Ratio of Quasi-Elastic Granular Soils under Cyclic Loading -- Raw Data

‘PS’ and ‘PF’ spreadsheets are the data of the prediction and calibration tests. (The data in this series are overall stress and strain information).

Supporting information


T111, Pingxin Xia, Longtan Shao, Wen Deng 2021 Missouri University of Science and Technology

T111, Pingxin Xia, Longtan Shao, Wen Deng

Stress-State Dependency of the Deformation Ratio of Quasi-Elastic Granular Soils under Cyclic Loading -- Raw Data

‘T’ series spreadsheets are the raw data of all tests. (The data in this series are overall stress and strain information).

Supporting information


Pf6, Pingxin Xia, Longtan Shao, Wen Deng 2021 Missouri University of Science and Technology

Pf6, Pingxin Xia, Longtan Shao, Wen Deng

Stress-State Dependency of the Deformation Ratio of Quasi-Elastic Granular Soils under Cyclic Loading -- Raw Data

‘PS’ and ‘PF’ spreadsheets are the data of the prediction and calibration tests. (The data in this series are overall stress and strain information).

Supporting information


T154, Pingxin Xia, Longtan Shao, Wen Deng 2021 Missouri University of Science and Technology

T154, Pingxin Xia, Longtan Shao, Wen Deng

Stress-State Dependency of the Deformation Ratio of Quasi-Elastic Granular Soils under Cyclic Loading -- Raw Data

‘T’ series spreadsheets are the raw data of all tests. (The data in this series are overall stress and strain information).

Supporting information


Dem, Pingxin Xia, Longtan Shao, Wen Deng 2021 Missouri University of Science and Technology

Dem, Pingxin Xia, Longtan Shao, Wen Deng

Stress-State Dependency of the Deformation Ratio of Quasi-Elastic Granular Soils under Cyclic Loading -- Raw Data

‘DEM’ spreadsheet is the simulation results. The test information of the numerical samples is included in it.

Supporting information


T113, Pingxin Xia, Longtan Shao, Wen Deng 2021 Missouri University of Science and Technology

T113, Pingxin Xia, Longtan Shao, Wen Deng

Stress-State Dependency of the Deformation Ratio of Quasi-Elastic Granular Soils under Cyclic Loading -- Raw Data

‘T’ series spreadsheets are the raw data of all tests. (The data in this series are overall stress and strain information).

Supporting information


T314, Pingxin Xia, Longtan Shao, Wen Deng 2021 Missouri University of Science and Technology

T314, Pingxin Xia, Longtan Shao, Wen Deng

Stress-State Dependency of the Deformation Ratio of Quasi-Elastic Granular Soils under Cyclic Loading -- Raw Data

‘T’ series spreadsheets are the raw data of all tests. (The data in this series are overall stress and strain information).

Supporting information


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