Publications
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Regional spectral analysis of moderate earthquakes in northeastern North America—Final Report to the Nuclear Regulatory Commission, Project V6240, Task 3
We analyze the Fourier spectra of S+Lg+surface wave groups from the horizontal and vertical components of broadband and accelerogram recordings of 120 small and moderate (2< Mw <6) earthquakes recorded by Canadian and American stations sited on rock at distances from 3 to 600 kilometers. There are seven Mw 4.0–4.5, six Mw 4.5–5.0, and three Mw ≥5 earthquakes in this event set. We test the regional
Authors
Jack Boatwright
Preface to the Focus Section on the Collaboratory for the Study of Earthquake Predictability (CSEP): New results and future directions
The Collaboratory for the Study of Earthquake Predictability (CSEP; Jordan, 2006) carries out fully prospective tests of earthquake forecasts, using fixed and standardized statistical tests and authoritative data sets, to assess the predictive skill of forecast models and to make objective comparisons between models. CSEP conducts prospective experiments at four testing centers around the world, a
Authors
Andrew J. Michael, Maximillian J. Werner
Reexamination of the subsurface fault structure in the vicinity of the 1989 moment-magnitude-6.9 Loma Prieta earthquake, central California, using steep-reflection, earthquake, and magnetic data
We reexamine the geometry of the causative fault structure of the 1989 moment-magnitude-6.9 Loma Prieta earthquake in central California, using seismic-reflection, earthquake-hypocenter, and magnetic data. Our study is prompted by recent interpretations of a two-part dip of the San Andreas Fault (SAF) accompanied by a flower-like structure in the Coachella Valley, in southern California. Initially
Authors
Edward Zhang, Gary S. Fuis, Rufus D. Catchings, Daniel S. Scheirer, Mark Goldman, Klaus Bauer
Broadband ground‐motion simulation of the 2011 Mw 6.2 Christchurch, New Zealand, earthquake
This study presents the details and results of hybrid broadband (0–10 Hz) ground‐motion simulations for the 2011 MwMw 6.2 Christchurch, New Zealand, earthquake. The simulations utilize a 3D velocity model and a kinematic source model with stochastic realizations of the slip amplitude, rise time, and rake angle. The resulting ground motions capture the salient basin amplification effects that are s
Authors
Hoby N. T. Razafindrakoto, Brendon A. Bradley, Robert Graves
Injection-induced moment release can also be aseismic
The cumulative seismic moment is a robust measure of the earthquake response to fluid injection for injection volumes ranging from 3100 to about 12 million m3. Over this range, the moment release is limited to twice the product of the shear modulus and the volume of injected fluid. This relation also applies at the much smaller injection volumes of the field experiment in France reported by Guglie
Authors
Arthur McGarr, Andrew J. Barbour
The limits of earthquake early warning: Timeliness of ground motion estimates
The basic physics of earthquakes is such that strong ground motion cannot be expected from an earthquake unless the earthquake itself is very close or has grown to be very large. We use simple seismological relationships to calculate the minimum time that must elapse before such ground motion can be expected at a distance from the earthquake, assuming that the earthquake magnitude is not predictab
Authors
Sarah E. Minson, Men-Andrin Meier, Annemarie S. Baltay, Thomas C. Hanks, Elizabeth S. Cochran
An updated stress map of the continental U.S. reveals heterogeneous intraplate stress
Knowledge of the state of stress in the Earth’s crust is key to understanding the forces and processes responsible for earthquakes. Historically, low rates of natural seismicity in the central and eastern United States have complicated efforts to understand intraplate stress, but recent improvements in seismic networks and the spread of human-induced seismicity have greatly improved data coverage.
Authors
Will Levandowski, Robert B Hermann, Richard W. Briggs, Oliver S. Boyd, Ryan D. Gold
Application of microtremor horizontal-to-vertical spectral ratio (MHVSR) analysis for site characterization: State of the art
Nakamura (Q Rep Railway Tech Res Inst 30:25–33, 1989) popularized the application of the horizontal-to-vertical spectral ratio (HVSR) analysis of microtremor (seismic noise or ambient vibration) recordings to estimate the predominant frequency and amplification factor of earthquake shaking. During the following quarter century, popularity in the microtremor HVSR (MHVSR) method grew; studies have v
Authors
S. Molnar, J. F. Cassidy, S. Castellaro, C. Cornou, H. Crow, J. A. Hunter, S. Matsushima, F. J. Sanchez-Sesma, Alan Yong
Interaction between hydraulic fracture and a preexisting fracture under triaxial stress conditions
Enhanced reservoir connectivity generally requires maximizing the intersection between hydraulic fracture (HF) and preexisting underground natural fractures (NF), while having the hydraulic fracture cross the natural fractures (and not arrest). We have studied the interaction between a hydraulic fracture and a polished saw-cut fault. The experiments include a hydraulic fracture initiating from a p
Authors
Saied Mighani, David A. Lockner, Brian D. Kilgore, Farrokh Sheibani, Brian Evans
A suite of exercises for verifying dynamic earthquake rupture codes
We describe a set of benchmark exercises that are designed to test if computer codes that simulate dynamic earthquake rupture are working as intended. These types of computer codes are often used to understand how earthquakes operate, and they produce simulation results that include earthquake size, amounts of fault slip, and the patterns of ground shaking and crustal deformation. The benchmark ex
Authors
Ruth A. Harris, Michael Barall, Brad T. Aagaard, Shuo Ma, Daniel Roten, Kim Olsen, Benchun Duan, Dunyu Liu, Bin Luo, Kangchen Bai, Jean-Paul Ampuero, Yoshihiro Kaneko, Alice-Agnes Gabriel, Kenneth Duru, Thomas Ulrich, Stephanie Wollherr, Zheqiang Shi, Eric Dunham, Sam Bydlon, Zhenguo Zhang, Xiaofei Chen, Surendra N. Somala, Christian Pelties, Josue Tago, Victor Manuel Cruz-Atienza, Jeremy Kozdon, Eric Daub, Khurram Aslam, Yuko Kase, Kyle Withers, Luis Dalguer
Leveraging geodetic data to reduce losses from earthquakes
Seismic hazard assessments that are based on a variety of data and the best available science, coupled with rapid synthesis of real-time information from continuous monitoring networks to guide post-earthquake response, form a solid foundation for effective earthquake loss reduction. With this in mind, the Earthquake Hazards Program (EHP) of the U.S. Geological Survey (USGS) Natural Hazards Missio
Authors
Jessica R. Murray, Evelyn A. Roeloffs, Benjamin A. Brooks, John O. Langbein, William S. Leith, Sarah E. Minson, Jerry L. Svarc, Wayne R. Thatcher
Numerical models of pore pressure and stress changes along basement faults due to wastewater injection: Applications to the 2014 Milan, Kansas Earthquake
We have developed groundwater flow models to explore the possible relationship between wastewater injection and the 12 November 2014 Mw 4.8 Milan, Kansas earthquake. We calculate pore pressure increases in the uppermost crust using a suite of models in which hydraulic properties of the Arbuckle Formation and the Milan earthquake fault zone, the Milan earthquake hypocenter depth, and fault zone geo
Authors
Elizabeth H. Hearn, Christine Koltermann, Justin R. Rubinstein