From Drifting to Anchored: Advances in Improving Absolute Hypocenter Location Accuracy for Natural, Induced and Explosion Seismic Events
Date: 4/24/2019
Time: 8:30 AM to 9:45 AM
Room: Cascade I
Accurate, absolute geographic location of seismic event hypocenters is important for characterizing seismic activity and estimating seismic hazard. The increasing societal demands for robust and actionable hazard estimation of natural and induced earthquakes, the requirements for nuclear explosion monitoring and other social and economic needs require improved hypocenter accuracy and robust error estimation. But, in general, seismic event locations are not well anchored to the geographic Earth because they depend on poorly distributed and distant seismogram measurements, simplified and erroneous Earth models and approximated physical processes. While many common hypocenter relocation methods can precisely constrain relative locations, hypocenters remain poorly constrained in absolute geographic coordinates. Only in rare cases is there relatively direct and accurate "ground truth" (GT) information on location that can be derived from static source displacement or from the known source of a human caused event or explosion.
Error estimates for seismic location fall into at least three main classes: (1) True, absolute geographic error (hypocenter - GT); (2) Nominal absolute error (nominal hypocenter uncertainties output by location algorithms or other analyses without GT); and (3) Nominal relative location errors. Here we welcome observational, theoretical and methodological contributions addressing determination of absolute geographic location of seismic events. We specifically ask - is it possible to achieve true absolute hypocenter estimates with representative uncertainties? If yes, what methods and data are needed to achieve this goal? We also welcome contributions on absolute and relative location procedures and their nominal error estimates that relate to improving absolute geographic location accuracy.
Conveners
Alexandros Savvaidis, Texas Seismological Network, Bureau of Economic Geology, University of Texas at Austin (alexandros.savvaidis@beg.utexas.edu)
Anthony Lomax, ALomax Scientific (alomax@free.fr)
William L. Yeck, National Earthquake Information Center, U.S. Geological Survey (wyeck@usgs.gov)
Stephen C. Myers, Atmospheric, Earth and Energy Division, Lawrence Livermore National Laboratory (myers30@llnl.gov)
Oral Presentations
Participant Role | Details | Start Time | Minutes | Action |
---|---|---|---|---|
Submission | Absolute Hypocentral Location Improvements With 3D Velocity Model Optimization: Application to Duvernay, Western Canada | 08:30 AM | 15 | View |
Submission | Accuracy and Uncertainty of TexNet Absolute Seismic Event Location in West Texas | 08:45 AM | 15 | View |
Submission | Feature-Based Bayesian Inference for Seismic Event Monitoring | 09:00 AM | 15 | View |
Submission | Machine Learning for Emulation of Seismic-Phase Travel Times in 3D Earth Models | 09:15 AM | 15 | View |
Submission | The IASPEI Reference Event (GT) List (1959-2017) Maintained by the ISC | 09:30 AM | 15 | View |
Total: | 75 Minute(s) |
From Drifting to Anchored: Advances in Improving Absolute Hypocenter Location Accuracy for Natural, Induced and Explosion Seismic Events
Description