A5018134198- Seismic Waves and Analysis
- Seismic Imaging and Inversion Techniques
- Geophysical Methods and Applications
- Landslides and related hazards
- Geophysical and Geoelectrical Methods
- Cryospheric studies and observations
- Bioenergy crop production and management
- Seismology and Earthquake Studies
- Forest ecology and management
- earthquake and tectonic studies
- Remote Sensing and LiDAR Applications
- Hydrocarbon exploration and reservoir analysis
- Geological and Geochemical Analysis
- Geological and Tectonic Studies in Latin America
- Distributed and Parallel Computing Systems
- Soil Moisture and Remote Sensing
- Spectroscopy and Laser Applications
- Methane Hydrates and Related Phenomena
- Climate change and permafrost
- Powder Metallurgy Techniques and Materials
- Image Processing and 3D Reconstruction
- Analytical Methods in Pharmaceuticals
- Drug Solubulity and Delivery Systems
- 3D Surveying and Cultural Heritage
- Hydraulic Fracturing and Reservoir Analysis
Pacific Northwest National Laboratory
2020-2023
Boise State University
2018-2021
University of Wyoming
2014-2018
Idaho National Laboratory
2018
University of Idaho
2017
Wyoming Department of Education
2014-2015
Bedrock weathering runs to the hills Fractures in bedrock drive breakdown of rock into soil. Soil makes observations processes challenging. St. Clair et al. combined a three-dimensional stress model with geophysical measurements show that erosion rates mirror changes topography (see Perspective by Anderson). Seismic reflection and electromagnetic profiles allowed mapping fracture density. The surface elevation thus provide way study critical zone between Science , this issue p. 534 ; see also 506
Abstract Observing the critical zone (CZ) below top few meters of readily excavated soil is challenging yet crucial to understanding Earth surface processes. Near‐surface geophysical methods can overcome this challenge by imaging CZ in three dimensions (3‐D) over hundreds meters, thus revealing lateral heterogeneity subsurface properties across scales relevant hillslope erosion, weathering, and biogeochemical cycling. We imaged under a soil‐mantled ridge developed granitic terrain Laramie...
Abstract Bedrock fractures influence the rates of surface processes that drive landscape evolution and are in turn influenced by landforms perturb ambient tectonic gravitational stress fields. In this modeling study, we examine how three‐dimensional topography regimes elastic fields bedrock fracture patterns beneath Earth's surface. We illustrate general effects landform orientation magnitude anisotropy using boundary element models stresses synthetic elongated ridges with different aspect...
Abstract. Many mountainous regions depend on seasonal snowfall for their water resources. Current methods of predicting the availability resources rely long-term relationships between stream discharge and snowpack monitoring at isolated locations, which are less reliable during abnormal snow years. Ground-penetrating radar (GPR) has been shown to be an effective tool measuring equivalent (SWE) because close relationship density velocity. However, standard velocity can time-consuming. Here we...
Abstract Although the Wasatch fault is currently known to have a high-seismic hazard from motion along range-bounding faults, new seismic data reveal faulted and folded 13,000–30,000-yr-old Lake Bonneville strata beneath Salt City (SLC). Coupled with previous excavation trench, borehole, other geologic geophysical observations, we conclude that zone of latest Pleistocene and/or Holocene faulting folding kinematically links East Bench Warm Springs faults through 3 km wide relay structure...
Abstract The convergent margin offshore Costa Rica shows evidence of subsidence due to subduction erosion along the outer forearc and relatively high rates uplift (∼3–6 mm/yr) coast. Recently erupted arc lavas exhibit a low 10 Be signal, suggesting that although nearly entire package incoming sediments enters zone, very little material is carried directly with downgoing Cocos plate magma generating depths mantle wedge. One mechanism would explain both coastal underplating sediments,...
Experimental combinations from the ranges assigned to independent factors were studied using both a low-shear (planetary) mixer and high-shear for granulation. The X1 calcium phosphate/mannitol ratio, X2 pregelatinized starch, X3 magnesium stearate, X4 type, X5 compression pressure. To optimize tablet properties fully, experimental range was varied -2 +2 units, with exception of X4, which -1 planetary +1 mixer. Drug dissolution did not seem be affected by but hardness type.
Abstract. Many mountainous regions depend on seasonal snowfall for their water resources. Current methods of predicting the availability resources rely long-term relationship between stream discharge and snow pack monitoring at isolated locations, which are less reliable during abnormal years. Ground-penetrating-radar (GPR) has been shown to be an effective tool measuring equivalent (SWE) because close density radar velocity. However, standard velocity can time consuming. Here we apply a...
A seismic land streamer campaign reveals complex faulting and folding within late Quaternary Bonneville lake sediments alluvial fan deposits beneath the downtown Salt Lake City urban corridor. From more than 15,000 shot gathers along 22 city streets, 35 km of two meter spaced data provide detailed character stratigraphy tectonics a step over region Wasatch fault system. We use first arrival tomography to obtain Vp distributions 20–30 m depth, Rayleigh wave inversions Vs profiles about 30...
We integrate vertically polarized P-SV converted bedrock refraction phase arrivals with first arrival and Rayleigh wave signals to estimate soil, fluid rock properties at a shallow site near Crested Butte, CO. validate our results synthetic elastic model. By combining the Vs derived from inversion results, we obtain composite model that is integrated Vp for hydrologic interpretation. The resulting analysis reveals zones of high Vp/Vs interpret as perched aquifer setting within colluvium....
ABSTRACT We present a simple and automated approach to estimate primary site-response resonance, layer thickness, shear-wave velocity directly from dispersion image for over half-space problem. demonstrate this high-impedance boundary conditions that lie in the upper tens of meters. Our eliminates need time-consuming curve picking 1D inversion large data volumes can capture structure profile. highlight important relationships between characteristics resonance parameters through synthetic...
Summary Over the past two years, Wyoming Center for Environmental Hydrology and Geophysics (WyCEHG) has imaged subsurface at five CZO’s: Calhoun, Boulder Creek, Eel River, Reynolds Southern Sierra. Techniques applied include seismic refraction, electrical resistivity, downhole logging, ground-penetrating radar, magnetic gradiometry, EMI, surface NMR. We will present results from these sites.
Summary We have collected 18 geophysical transects of resistivity and p-wave velocities in a catchment the Laramie Range, Wyoming to identify structures that influence movement storage water. When we independently invert data, observe similar velocity data despite being completely different parameters. map seismic over hydrostratigraphic boundaries areas high fluid saturation.
PreviousNext You have accessSymposium on the Application of Geophysics to Engineering and Environmental Problems 2015Hydrogeophysics, CZO, Marine, Polar Integrated Case HistoriesAuthors: Stanley NwokebuiheAbdulrahman AlotaibiEvgeniy TorgashovNeil AndersonAdel ElkrryRichard FunkRobert FeldpauschBrent JohnstonGeorgios TassisJan Steiner RønningPanagiotis TsourlosTorleif DahlinTian XuJohn DunbarCarol LutkenPaul HigleyMichaela MerzTodd CaldwellChuck AboltMichael YoungToti LarsonEric PetersenJohn...
Sap flow measurement using heat sensors is popular technique for measuring tree water use. However, these measurements are local and their accuracy depends largely on the of estimating entire sapwood area. Ground Penetrating Radar (GPR) Electrical resistivity Tomography (ERT) suitable technologies mapping moisture content variations, since both methods highly sensitive to changes in saturation. Here we describe a coupled ERT GPR data processing approach estimate within trunks. The results...