Oliver Boyd
The USGS Mendenhall program has a post-doctoral opportunity (#20-24) for recent graduates interested in full waveform inversion and earthquake hazards entitled "Applications of full-waveform inversion for high-resolution seismic velocity models and site response in support of earthquake ground motion investigations".
Ground motion characterization represents one of the greatest uncertainties in probabilistic seismic-hazard analysis. While advances in 3-D ground motion simulations are prompting their serious consideration for inclusion in next-generation seismic-hazard models, many important scientific issues affecting accurate ground motion prediction remain. First among them is development of robust high-resolution seismic velocity models, which is a critical step for characterizing subsurface geologic properties and understanding anelastic wave propagation caused by both path and site effects. Over the past 15 years, full-waveform inversion (FWI) has become an emerging tool in earthquake seismology parallel to advances in computational resources and numerical methods from crustal (i.e., sedimentary basin) to global scales providing high-resolution images in densely instrumented and seismically active regions. However, even with the advent of ambient noise and microtremor array techniques and advances in noise FWI theory for obtaining shear-wave velocities, there are very few studies to date using these data in an FWI framework due to adverse effects of, for example, uneven source distributions and measurement techniques on the resolution of tomographic models. Thus, there is a need to explore both state-of-the-art ambient noise and multi-method (both active- and passive-source) high-frequency multi-component datasets with FWI for characterizing earthquake wave propagation phenomena such as basin-edge effects, converted phase generation, attenuation, and site response.
We seek a postdoctoral candidate to conduct research on problems that utilize full-waveform inversion to resolve seismic structure in regions of importance for characterizing earthquake ground motions and improving estimates of seismic hazards. The research effort will be largely determined by the postdoctoral fellow’s background and interests but ideally will broadly align with our interests in seismic hazards in the United States including the Wasatch Front, Utah, the Mississippi Embayment and Atlantic and Gulf Coastal Plains, the Pacific Northwest, and the Cook Inlet region of Alaska.
Applications are due January 6th, 2022, and more information about the program, the opportunity, and how to apply can be found at https://www.usgs.gov/centers/mendenhall. Please don't hesitate to reach out to us if you have questions about this opportunity.
Proposed duty station: Golden, Colorado
Research advisors: Oliver Boyd (olboyd<at>usgs.gov), Bill Stephenson (wstephens<at>usgs.gov), Morgan Moschetti (mmoschetti<at>usgs.gov), Erin Wirth (ewirth<at>usgs.gov), and Ebru Bozdag (bozdag<at>mines.edu)
Ground motion characterization represents one of the greatest uncertainties in probabilistic seismic-hazard analysis. While advances in 3-D ground motion simulations are prompting their serious consideration for inclusion in next-generation seismic-hazard models, many important scientific issues affecting accurate ground motion prediction remain. First among them is development of robust high-resolution seismic velocity models, which is a critical step for characterizing subsurface geologic properties and understanding anelastic wave propagation caused by both path and site effects. Over the past 15 years, full-waveform inversion (FWI) has become an emerging tool in earthquake seismology parallel to advances in computational resources and numerical methods from crustal (i.e., sedimentary basin) to global scales providing high-resolution images in densely instrumented and seismically active regions. However, even with the advent of ambient noise and microtremor array techniques and advances in noise FWI theory for obtaining shear-wave velocities, there are very few studies to date using these data in an FWI framework due to adverse effects of, for example, uneven source distributions and measurement techniques on the resolution of tomographic models. Thus, there is a need to explore both state-of-the-art ambient noise and multi-method (both active- and passive-source) high-frequency multi-component datasets with FWI for characterizing earthquake wave propagation phenomena such as basin-edge effects, converted phase generation, attenuation, and site response.
We seek a postdoctoral candidate to conduct research on problems that utilize full-waveform inversion to resolve seismic structure in regions of importance for characterizing earthquake ground motions and improving estimates of seismic hazards. The research effort will be largely determined by the postdoctoral fellow’s background and interests but ideally will broadly align with our interests in seismic hazards in the United States including the Wasatch Front, Utah, the Mississippi Embayment and Atlantic and Gulf Coastal Plains, the Pacific Northwest, and the Cook Inlet region of Alaska.
Applications are due January 6th, 2022, and more information about the program, the opportunity, and how to apply can be found at https://www.usgs.gov/centers/mendenhall. Please don't hesitate to reach out to us if you have questions about this opportunity.
Proposed duty station: Golden, Colorado
Research advisors: Oliver Boyd (olboyd<at>usgs.gov), Bill Stephenson (wstephens<at>usgs.gov), Morgan Moschetti (mmoschetti<at>usgs.gov), Erin Wirth (ewirth<at>usgs.gov), and Ebru Bozdag (bozdag<at>mines.edu)
