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Does Updating Natural Hazard Maps To Reflect Best Practices Increase Viewer Comprehension Of Risk?, Carson C. MacPherson-Krutsky, Brittany D. Brand, Michael K. Lindell 2020 Boise State University

Does Updating Natural Hazard Maps To Reflect Best Practices Increase Viewer Comprehension Of Risk?, Carson C. Macpherson-Krutsky, Brittany D. Brand, Michael K. Lindell

Geosciences Faculty Publications and Presentations

In this study, we examine whether updating an interactive hazard map using recommendations from the literature improves user map comprehension. Analyses of experimental data collected from 75 university students revealed that map comprehension scores were not significantly better for those who viewed a “best practices” map compared to those who viewed an existing version. This may be because the existing map was itself better than most other interactive maps. Additionally, we found map comprehension levels to have significant positive relationships with objective tests, but not self-reported measures of spatial ability. Moreover, self-reported spatial ability had statistically significant, but only moderately ...


Preparation And Mitigation Efforts For Volcanic Hazards In The Pacific Northwest, Nick Griffith 2020 Western Oregon University

Preparation And Mitigation Efforts For Volcanic Hazards In The Pacific Northwest, Nick Griffith

Academic Excellence Showcase Proceedings

Volcanic eruptions represent one of the most serious geologic hazards facing the Pacific Northwest, with several volcanoes located within striking distance of the most highly populated areas in the region. This paper describes the hazards associated with these eruptive centers and discusses the best practices for preparing communities for potential eruptions and mitigating volcanic hazards. This study is based on data collected by the United States Geological Survey (USGS) on volcanic systems such as Mt. St. Helens and Mt. Rainier. Many other scientific organizations have studied analogous volcanic systems beyond the Pacific Northwest, such as the volcanically active island of ...


Soil Moisture Contributions To Insar Phase And Decorrelation, Yusuf Eshqi Molan 2020 Southern Methodist University

Soil Moisture Contributions To Insar Phase And Decorrelation, Yusuf Eshqi Molan

Earth Sciences Theses and Dissertations

Interferometric synthetic aperture radar (InSAR) provides capability to detect surface deformation. Between two SAR images, in addition to ground surface deformations, changes may happen in the surface parameters such as soil moisture, vegetation layer water content, and so on. Despite deformation, the other changes may not be of interest for a common InSAR analysis and an ordinary InSAR analysis rarely takes into account their influences on InSAR phase and coherence. The effect of the changes on InSAR phase and coherence can potentially impede accurate estimation of ground surface deformation but also can open new window into soil moisture retrieval and ...


Crystal Queer: Fracturing The Binaries Of Matter, Creation, And Landscape, Sarah Knight 2020 Washington University in St. Louis

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 ...


On The Seismic Performance Of Skewed Special Moment Frame Reduced Beam Section Connections, Damaso Daniel Dominguez 2020 University of Arkansas, Fayetteville

On The Seismic Performance Of Skewed Special Moment Frame Reduced Beam Section Connections, Damaso Daniel Dominguez

Theses and Dissertations

Special Moment Frames (SMFs) are frequently used in high seismic areas for architecturally constrained designs, as they provide lateral system stiffness without the use of braces which often obstruct views and architectural features. Reduced beam section (RBS) connections are popular SMF connection details developed following the Northridge earthquake to limit brittle fractures within connection welds. Current American Institute of Steel Construction (ASIC) provisions (i.e. AISC 341-16) provide prequalified SMF RBS connection details (including welding requirements); however, all prequalified details only consider orthogonal connections between the beam and column. This dissertation investigates the effect of adding skew within SMF RBS ...


Exploration Of Abandoned Mine Shafts By Means Of Seismic Refraction, Electrical Resistivity Tomography, And Ground Penetrating Radar: Case Study At Centralia, Pa, Jackson Long 2020 Susquehanna University

Exploration Of Abandoned Mine Shafts By Means Of Seismic Refraction, Electrical Resistivity Tomography, And Ground Penetrating Radar: Case Study At Centralia, Pa, Jackson Long

Senior Scholars Day

Near surface geophysical methods have been heavily used in mapping geological structures, and in the identification of mine shafts and underground void spaces. In this study, a site in Centralia, PA, was selected as an experimental site to study the relative effectiveness of Seismic Refraction (SR), Electrical Resistivity Tomography (ERT), and Ground Penetrating Radar (GPR) to detect abandoned mine shafts. Centralia is well known for its extensive mine fire, as well as many abandoned mines. All surveys were performed along the same transect at Centralia. SR and ERT were appeared to be the effective methods of mine shaft detection. Dipole-Dipole ...


An Analysis Of The Reactivation Potential Of A Deep-Seated Landslide In The Oregon Coast Range Under Varying Hydrologic Conditions With Seismic Triggering, Emily E. Smoot 2020 Portland State University

An Analysis Of The Reactivation Potential Of A Deep-Seated Landslide In The Oregon Coast Range Under Varying Hydrologic Conditions With Seismic Triggering, Emily E. Smoot

Anthós

Landslides can occur in many locations across the world and have the potential to be extremely destructive if failures occur near populated areas. Failures are most likely to occur on slopes that have already experienced numerous failures. This means they are a considerable hazard, and the risk involved with building in areas that have previously experienced landslides should be adequately understood. This study examines the reactivation potential of a deep-seated landslide located in the Oregon Coast Range. The analysis of this landslide included creating a map of the surface morphology and computing the factor of safety for the deposit using ...


Earthquake Site Characterization Of Rock Sites In Eastern Canada And Stiff Ground Sites In Vancouver, British Columbia, Sameer Ladak 2020 The University of Western Ontario

Earthquake Site Characterization Of Rock Sites In Eastern Canada And Stiff Ground Sites In Vancouver, British Columbia, Sameer Ladak

Electronic Thesis and Dissertation Repository

Site characterization is a crucial component in assessing seismic hazard, typically involving in situ shear-wave velocity (VS) depth profiling, and measurement of site amplification including site period. These methods are ideal for soil sites and less reliable in more complex geologic settings including rock sites. A multi-method approach to earthquake site characterization is tested at 25 seismograph stations across Eastern Canada. It is typically assumed these stations are installed on hard rock. We seek to identify which site characterization methods are most suitable at rock sites as well as to confirm the hard rock assumption. Active-source refraction and surface ...


Testing A Drone-Based Magnetic Field Surveying System, Erik Jacobson, Irina Filina 2020 University of Nebraska-Lincoln

Testing A Drone-Based Magnetic Field Surveying System, Erik Jacobson, Irina Filina

UCARE Research Products

Aeromagnetic surveys are conducted by geoscientists to study subsurface geologic structures, such as faults. This type of survey uses a magnetometer mounted upon an airborne vehicle to collect magnetic field data. Magnetic anomalies are caused by variations in subsurface geology, namely in magnetic properties of subsurface rocks. Jacobson and Filina (2019) reported on the development of a new low cost drone, based magnetic field surveying system by the UNL Geophysics Team. This drone-based magnetic system is capable of collecting high resolution data at low speeds and low altitudes. The current study focuses on testing this system by conducting two flights ...


A Geophysical Survey Near Blacktail Creek In The Thompson Park Area Near Butte, Montana, Guolong Wu 2020 Montana Tech

A Geophysical Survey Near Blacktail Creek In The Thompson Park Area Near Butte, Montana, Guolong Wu

Graduate Theses & Non-Theses

Subsurface electrical information can be obtained by electrical and self-potential methods. These geophysical methods, compared to drilling, provide a much cheaper option for investigating the hydrogeological setting. In this project report, we carried out resistivity and self-potential survey along Blacktail Creek in the Thompson Park area near Butte, Montana to understand the hydrogeological setting.

Three geophysical methods have been used: 2D electrical resistivity, 3D electrical resistivity, and self-potential. The least-square inversion resistivity model results showed a general variation of resistivity with depth and delineated the extent of the ground water. The ERT results show three electrical layers, one of them ...


Feel The Vibration! Measuring The Ground Motion Caused By Racecars At The Zmax Dragway, Gabrielle Herrin 2020 University of South Carolina - Columbia

Feel The Vibration! Measuring The Ground Motion Caused By Racecars At The Zmax Dragway, Gabrielle Herrin

Senior Theses

Dragsters raced down a 1,000 ft track at the zMAX Dragway and the resulting ground motion was recorded, analyzed, and displayed live to fans. At the NGK Spark Plugs NHRA Four-Wide Nationals on April 26 – 28, 2019 and the NTK NHRA Carolina Nationals on October 11-13, 2019 the ground motion was recorded with novel devices anchored on the track walls. The devices were fit with Raspberry Pis, precise clocks, and accelerometers recording at 400 samples per second. In April, the geometry of the devices was located near the start line and in October, devices were anchored to the outside ...


Characterization Of Magma Storage And Dynamics At Akutan, Semisopochnoi, And Okmok Volcanoes From Analytical And Numerical Models Of Geodetic, Seismic, And Petrologic Data, Kimberly DeGrandpre 2020 Southern Methodist University

Characterization Of Magma Storage And Dynamics At Akutan, Semisopochnoi, And Okmok Volcanoes From Analytical And Numerical Models Of Geodetic, Seismic, And Petrologic Data, Kimberly Degrandpre

Earth Sciences Theses and Dissertations

Volcanic eruptions can cause significant socioeconomic loss, but a better understanding of the processes and dynamics influencing the evolution of volcanic plumbing systems will advance the development of eruption forecasting models that will ultimately mitigate hazards and risks associated with eruptive events. Geologic and geophysical data must be integrated in 3D, finite- element, multiphysical, numerical models to define the coupled evolution of magmatic and crustal stress regimes in volcanic environments, but in data limited regions this is not always an option. The remote nature of the Aleutian Island Arc restricts ground-based monitoring and sampling efforts, and due to sparse temporal ...


Nanoindentation Characterization Of Elastic Properties Of Shales And Swelling Clay Minerals, Shengmin Luo 2020 University of Massachusetts Amherst

Nanoindentation Characterization Of Elastic Properties Of Shales And Swelling Clay Minerals, Shengmin Luo

Doctoral Dissertations

Oil and gas shales are a class of multiscale, multiphase, hybrid inorganic-organic sedimentary rocks that consist of a generally uniform, preferentially oriented clay matrix with randomly embedded silt and sand particles as solid inclusions. A thorough understanding of the mechanical properties of shales is crucial for the exploration and production of oil and gas in the unconventional shale reservoirs, but it can be a challenging task due to their nature of compositional heterogeneity and microstructural anisotropy. In efforts to better characterize the mechanical properties of shales across different length scales and to fundamentally understand the laws of upscaling from individual ...


Source Parameters Of Induced Seismicity In North America, Joanna M. Holmgren 2020 The University of Western Ontario

Source Parameters Of Induced Seismicity In North America, Joanna M. Holmgren

Electronic Thesis and Dissertation Repository

Source parameters of earthquakes play a key role in the understanding of earthquake behavior and modelling of seismic hazard. They describe the size of earthquakes, including how much energy is generated during the rupture, and how the ground motion is distributed over different frequency bands and azimuths. The last decade’s increase in induced seismicity caused by oil and gas production has led to an interest in understanding the underlying earthquake processes and how they can be modelled. This thesis is divided into three studies, each examining source parameters of induced earthquakes in North America.

In the first study, I ...


What Is The Most Threatening Disaster To The Continental United States?, Aaron Spomer, Elijah Kaufman, Julisa Prieto-Garcia, Brooke Aschwanden 2020 University of Nebraska at Omaha

What Is The Most Threatening Disaster To The Continental United States?, Aaron Spomer, Elijah Kaufman, Julisa Prieto-Garcia, Brooke Aschwanden

Student Research and Creative Activity Fair

Our goal for our project is to fully understand which natural disaster is the most destructive to the United States. We have chosen to compare hurricanes, floods, tornadoes, wildfires, earthquakes, and nor’easters. We have researched the cost of the total damage and repair, how the warning systems have improved over time, the death tolls from each, and also the frequency at which each one occurs. Each group member will research a different disaster impact, and the data will create a comprehensive view of the level of devastation each disaster has. We collected data all the way from the early ...


Hydraulic Tomography: 3d Hydraulic Conductivity, Fracture Network, And Connectivity In Mudstone, Claire R. Tiedeman, Warren Barrash 2020 U.S. Geological Survey

Hydraulic Tomography: 3d Hydraulic Conductivity, Fracture Network, And Connectivity In Mudstone, Claire R. Tiedeman, Warren Barrash

CGISS Publications and Presentations

We present the first demonstration of hydraulic tomography (HT) to estimate the three‐dimensional (3D) hydraulic conductivity (K) distribution of a fractured aquifer at high‐resolution field scale (HRFS), including the fracture network and connectivity through it. We invert drawdown data collected from packer‐isolated borehole intervals during 42 pumping tests in a wellfield at the former Naval Air Warfare Center, West Trenton, New Jersey, in the Newark Basin. Five additional tests were reserved for a quality check of HT results. We used an equivalent porous medium forward model and geostatistical inversion to estimate 3D K at high resolution (K ...


Thermal Analysis, Compressibility, And Decomposition Of Synthetic Bastnäsite-(La) To Lanthanum Oxyfluoride, Richard L. Rowland, Barbara Lavina, Kathleen E. Vander Kadeen, Lisa R. Danielson, Pamela C. Burnely 2020 Los Alamos National Laboratory

Thermal Analysis, Compressibility, And Decomposition Of Synthetic Bastnäsite-(La) To Lanthanum Oxyfluoride, Richard L. Rowland, Barbara Lavina, Kathleen E. Vander Kadeen, Lisa R. Danielson, Pamela C. Burnely

Geoscience Faculty Publications

Understanding basic material properties of rare earth element (REE) bearing minerals such as their phase stability and equations of state can assist in understanding how economically viable deposits might form. Bastnäsite is the most commonly mined REE bearing mineral. We synthesized the lanthanum-fluoride end member, bastnäsite-(La) (LaCO3F), and investigated its thermal behavior and decomposition products from 298 K to 1173 K under ambient pressure conditions through thermogravimetric analysis, differential scanning calorimetry, evolved gas analysis, and high temperature powder X-ray diffraction. We also investigated the compressibility of bastnäsite-(La) via single crystal X-ray diffraction in diamond anvil cells at an ...


Constraints On The Shallow Deformation Around The Main Frontal Thrust In Central Nepal From Refraction Velocities, Yixiang Liu, Judith Hubbard, Rafael V. Almeida, Anna Foster, Lee Liberty, Ying Sin Lee, Soma Nath Sapkota 2020 Nanyang Technological University

Constraints On The Shallow Deformation Around The Main Frontal Thrust In Central Nepal From Refraction Velocities, Yixiang Liu, Judith Hubbard, Rafael V. Almeida, Anna Foster, Lee Liberty, Ying Sin Lee, Soma Nath Sapkota

Geosciences Faculty Publications and Presentations

The youngest fault system in the Himalayan orogeny is the Main Frontal Thrust (MFT), the frontal ramp of the Main Himalayan Thrust, which is expected to host the largest and most damaging earthquakes in Nepal. We characterize the upper few hundred meters below the surface across two MFT fault strands using ten high-resolution seismic profiles that we acquired in 2014 and 2015 with a 6-tonne Vibroseis source. We use first arrival picks from 625,416 seismic traces to derive P-wave seismic velocity models using a wavepath eikonal traveltime inversion method, and derive estimates of alluvium thickness and water table depth ...


New Magnetic Field Models Of The Moon, Dhananjay Ravat, Michael E. Purucker, Nils Olsen 2020 University of Kentucky

New Magnetic Field Models Of The Moon, Dhananjay Ravat, Michael E. Purucker, Nils Olsen

Earth and Environmental Sciences Research Data

We use L1-norm model regularization of |Br| component at the surface on magnetic monopoles bases and along-track magnetic field differences alone (without vector observations) to derive high quality global magnetic field models at the surface of the Moon. The practical advantages to this strategy are: monopoles are more stable at closer spacing in comparison to dipoles, improving spatial resolution; L1-norm model regularization leads to sparse models which may be appropriate for the Moon which has regions of localized magnetic field features; and along-track differences reduce the need for ad-hoc external field noise reduction strategies. We examine also the use ...


Co-Eruptive Tremor From Bogoslof Volcano: Seismic Wavefield Composition At Regional Distances, Matthew M. Haney, David Fee, Kathleen F. McKee, John J. Lyons, Robin S. Matoza, Aaron G. Wech, Gabrielle Tepp, Cheryl Searcy, T. Dylan Mikesell 2020 Alaska Volcano Obervatory

Co-Eruptive Tremor From Bogoslof Volcano: Seismic Wavefield Composition At Regional Distances, Matthew M. Haney, David Fee, Kathleen F. Mckee, John J. Lyons, Robin S. Matoza, Aaron G. Wech, Gabrielle Tepp, Cheryl Searcy, T. Dylan Mikesell

Geosciences Faculty Publications and Presentations

We analyze seismic tremor recorded during eruptive activity over the course of the 2016–2017 eruption of Bogoslof volcano, Alaska. Only regional recordings of the tremor wavefield exist for Bogoslof, making it a challenge to place the recordings in context with other eruptions that are normally captured by local seismic data. We apply a technique of time-frequency polarization analysis to three-component seismic data to reveal the wavefield composition of Bogoslof eruption tremor.We find that at regional distances, the tremor is dominated by P-waves in the band from 1.5 to 10 Hz. Using this information, along with an enriched ...


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