Manual Correlation of Seismic Arrivals to Improve Hypocenter Locations for the 1993 Rock Valley Sequence in Nevada
Description:
Correlation analysis of the timing of seismic arrivals is a common procedure to improve
locations, but can only be performed on events with similar magnitudes and that are near each
other. The series of shallow events that occurred during the 1993 Rock Valley sequence in
Nevada is targeted for investigating the difference between natural and explosive sources.
These historic waveforms provide magnitudes up to ml 4.3 and we focus on a subset of wellrecorded
events in the range of ml 2.5‐4.3. Most of the waveforms for these largest events are
clipped at the nearest stations, however, due to the geologic complexity of the region,
traditional correlation methods were unable to provide consistent new arrival times. A
consortium of scientists from five institutions individually picked the subset of events and
produced an average pick difference of 0.05 s and median error of 0.02 s (when all 5 institutions
provided picks). To build a common set of reviewed picks, the waveforms were manually
correlated and visually inspected to provide a common pick within two samples for each event
and station. When used to relocate the events, the common set of picks provided locations that
trended closer to the expected fault orientations. These improved locations were then used to
help provide constraints for the development of a testbed at Rock Valley to conduct chemical
explosive tests for comparison to the earthquake events.
This work was done by Mission Support and Test Services, LLC, under Contract No. DE‐NA0003624 with the
U.S. Department of Energy and the NNSA Office of Defense Nuclear Nonproliferation. DOE/NV/03624‐‐1538. SNL is managed and operated by NTESS under DOE NNSA contract DE-NA0003525
Session: It’s All About Relocation, Relocation, Relocation
Type: Oral
Date: 4/20/2023
Presentation Time: 05:15 PM (local time)
Presenting Author: Cleat Zeiler
Student Presenter: No
Invited Presentation:
Authors
Cleat Zeiler Presenting Author Corresponding Author zeilercp@nv.doe.gov Nevada National Security Site |
Michelle Scalise scalisme@nv.doe.gov Nevada National Security Site |
Ken Smith ken@unr.edu University of Nevada, Reno |
Ting Chen tchen@lanl.gov Los Alamos National Laboratory |
Scott Phillips wsp@lanl.gov Los Alamos National Laboratory |
Charlotte Rowe char@lanl.gov Los Alamos National Laboratory |
Moira Pyle pyle4@llnl.gov Lawrence Livermore National Laboratory |
Leiph Preston lpresto@sandia.gov Sandia National Laboratories |
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Manual Correlation of Seismic Arrivals to Improve Hypocenter Locations for the 1993 Rock Valley Sequence in Nevada
Category
It’s All About Relocation, Relocation, Relocation