A5078199113- Seismic Waves and Analysis
- Geophysical Methods and Applications
- Seismic Imaging and Inversion Techniques
- Geophysical and Geoelectrical Methods
- Cryospheric studies and observations
- Landslides and related hazards
- Groundwater flow and contamination studies
- Seismology and Earthquake Studies
- Geology and Paleoclimatology Research
- Geological Modeling and Analysis
- Geochemistry and Geologic Mapping
- Climate change and permafrost
- Methane Hydrates and Related Phenomena
- Planetary Science and Exploration
- earthquake and tectonic studies
- Reservoir Engineering and Simulation Methods
- Hydrology and Sediment Transport Processes
- Underwater Acoustics Research
- Winter Sports Injuries and Performance
- Hydraulic Fracturing and Reservoir Analysis
- Archaeology and Historical Studies
- Geophysics and Sensor Technology
- Drilling and Well Engineering
- Water Quality and Resources Studies
- Hydrocarbon exploration and reservoir analysis
SPX Corporation (United States)
2024
Technical Design (United States)
2024
Arcadis (United States)
2024
Australian Astronomical Observatory
2024
Macquarie University
2024
Colorado Mesa University
2023
University of Calgary
2016-2019
University of Kansas
1997-2018
Slippery Rock University
2017
The Ohio State University
2017
We introduce the 4-metre Multi-Object Spectroscopic Telescope (4MOST), a new high-multiplex, wide-field spectroscopic survey facility under development for four-metre-class Visible and Infrared Survey Astronomy (VISTA) at Paranal. Its key specifications are: large field of view (FoV) 4.2 square degrees high multiplex capability, with 1624 fibres feeding two low-resolution spectrographs ($R = λ/Δλ\sim 6500$), 812 transferring light to high-resolution spectrograph \sim 20\,000$). After...
Three distinct seismic reflections were obtained from within the upper 2.1 m of flood‐plain alluvium in Arkansas River valley near Great Bend, Kansas. Reflections observed at depths 0.63, 1.46, and 2.10 confirmed by finite‐difference wave‐equation modeling. The wavefield was densely sampled placing geophones 5‐cm intervals, near‐source nonelastic deformation minimized using a very small impulse source. For to be visible this shallow range, low P ‐wave velocities (<300 m/s) high...
The application of geophysical methods, in particular, electrical resistivity measurements, may be useful for monitoring subsurface contamination. However, interpreting data without additional and considering the associated hydrogeochemical processes is challenging since response sensitive to not only heterogeneity rock properties but also saturation chemical composition pore fluids. We present an inverse modeling framework that incorporates simulation time‐lapse apply it various borehole...
Freshwater harmful algal blooms (HABs), caused mostly by toxic cyanobacteria, produce a range of cyanotoxins that threaten the health humans and domestic animals. Climate conditions anthropogenic influences such as agricultural run-off can alter onset intensity HABs. Little is known about distribution spread freshwater Current sampling protocols in some lakes involve teams researchers collect samples hand from boat and/or shoreline. Water be collected surface, discrete-depth collections,...
Abstract The Gemini South telescope is now equipped with a new high-resolution spectrograph called the High-resolution Optical SpecTrograph (GHOST). This instrument provides high-efficiency, spectra covering 347–1060 nm in single exposure of either one or two targets simultaneously, along precision radial velocity spectroscopy utilizing an internal calibration source. It can operate at spectral element resolving power 76,000 56,000, and reach signal-to-noise ratio ∼5 1 hr on V ∼ 20.8 mag...
Charles Darwin considered himself to be a geologist and published extensively on many geologic phenomena. He was intrigued with the distribution of erratic boulders speculated upon their origins. In his accounts voyage HMS Beagle, described crystalline notable size abundance near Bahia San Sebastian, south Strait Magellan, Tierra del Fuego. Influenced by Lyell’s reflections slow, vertical movements crust, submer gence, ice rafting explain drift, proposed that Sebastian were ice-rafted....
For reflected‐wave phenomena in both seismology and ground‐penetrating radar (GPR), the amplitudes of reflected waves depend on incidence angles physical properties media above below an interface. Amplitude variation with offset (AVO) analysis employs knowledge to constrain two at Ostrander (1984) demonstrated that AVO can be used seismic reflection data certain instances obtain information about subsurface not revealed by traveltime‐offset relationships (i. e., traditional cross sections)....
Seismic P-wave velocities in near‐surface materials can be much slower than the speed of sound waves air (normally 335 m/s or 1100 ft/s). Difficulties often arise when measuring these low‐velocity P-waves because interference by wave and air‐coupled near seismic source, at least gathering data with more commonly used shallow sources. Additional problems separating direct refracted arrivals within ∼2 m source from source‐generated nonlinear displacement, even small energy sources such as...
To observe flow channeling in situ, surface ground‐penetrating radar (GPR) was used to detect a saline tracer moving through sub‐horizontal bedrock fracture. The is mapped using amplitude variations resulting from the significant difference electromagnetic properties between and natural ground water within Results show that hydrogeophysical investigations GPR can successfully image movement variety of configurations three spatial dimensions time (hence 4D). Observed travel paths demonstrated...
A 300-m near‐surface seismic reflection profile was collected in southeastern Kansas to locate a fault(s) associated with recognized stratigraphic offset on either side of region unexposed bedrock. substantial increase the S/N ratio final stacked section achieved by muting all data arriving time after airwave. Methods applying traditional processing techniques (200 ms or less) often differ notably from hydrocarbon exploration‐scale (3–4 s more). The example noise cone used is contrary normal...
Shallow seismic reflection surveys require dense spatial wave‐field sampling, contributing to their high cost. To assess the feasibility of planting geophones automatically, we planted 72 in approximately 2 s a test line, using an 11‐m‐wide farm tillage tool as device. Geophones were attached rigidly, at 15 cm intervals, five pieces heavy‐duty channel iron bolted tillage‐tool frame. Conventional comparison‐line data collected about 75 away, parallel visually comparable with source 12 m...
In many near‐surface applications, detailed subsurface characterization is important. Characterization often obtained using ground‐penetrating radar (GPR) or shallow seismic‐reflection (SSR) imaging methods, depending upon depth of interest and surficial geology. Each method responds to different physical properties; thus, each may produce images the same volume. By incorporating two we generated a cross‐section at an alluvial test site identified depths three interfaces accurately ±5 cm. We...
Implementation of active-learning practices into science, technology, engineering, and mathematics (STEM) courses has been shown to increase student learning performance, improve retention material, reduce achievement gaps among different populations when compared lecture-based approaches. To this end, we transformed two large-enrollment introductory geoscience (160 270 60 190 students) at a large public university in the midwestern United States classrooms, systematically analyzed data over...
Abstract Ultrashallow seismic-reflection data were collected at a test site in Great Bend, Kansas. The purpose of the experiment was to image seasonal submeter-scale fluctuations water table over period one year identify factors important monitoring when using techniques. study indicates that detailed velocity information must be used interpreting water-table levels. Using as control depth-converting seismic profiles yielded correct positioning within + or -12 cm site.
We develop a Bayesian model to invert surface seismic refraction data with depth constraints from boreholes for characterization of aquifer geometry and apply it borehole sets collected at the contaminated Oak Ridge National Laboratory site in Tennessee. Rather than traditional approach first inverting arrival times velocity then using that information aid spatial interpolation wellbore data, we jointly time wellbore‐based information, such as depths key lithological boundaries. use...
Research Article| May 01, 2006 Regional-scale assessment of a sequence-bounding paleosol on fluvial fans using ground-penetrating radar, eastern San Joaquin Valley, California George L. Bennett, V; V 1Department Geological Sciences, Michigan State University, 206 Natural Sciences Building, East Lansing, 48824-0001, USA Search for other works by this author on: GSW Google Scholar Gary S. Weissmann; Weissmann Gregory Baker; Baker 2Department Earth and Planetary 1412 Circle Drive, University...
Startling national statistics continue to illuminate the need for increasing number of underrepresented minority students graduating with degrees in geosciences. With populations U.S., diversity becomes a key issue sustained success college geoscience departments. The under-funded Buffalo Public School system struggles provide quality science education students, which leads few minorities pursuing STEM (Science, Technology, Engineering and Math) local colleges universities. Geosciences...