The use of multiwavelets for uncertainty estimation in seismic surface wave dispersion.
Abstract
This report describes a new singlestation analysis method to estimate the dispersion and uncer tainty of seismic surface waves using the multiwavelet transform. Typically, when estimating the dispersion of a surface wave using only a single seismic station, the seismogram is decomposed into a series of narrowband realizations using a bank of narrowband filters. By then enveloping and normalizing the filtered seismograms and identifying the maximum power as a function of frequency, the group velocity can be estimated if the sourcereceiver distance is known. However, using the filter bank method, there is no robust way to estimate uncertainty. In this report, I in troduce a new method of estimating the group velocity that includes an estimate of uncertainty. The method is similar to the conventional filter bank method, but uses a class of functions, called Slepian wavelets, to compute a series of wavelet transforms of the data. Each wavelet transform is mathematically similar to a filter bank, however, the timefrequency tradeoff is optimized. By taking multiple wavelet transforms, I form a population of dispersion estimates from which stan dard statistical methods can be used to estimate uncertainty. I demonstrate the utility of this new method by applying it to syntheticmore »
 Authors:
 Sandia National Lab. (SNLNM), Albuquerque, NM (United States)
 Publication Date:
 Research Org.:
 Sandia National Lab. (SNLNM), Albuquerque, NM (United States)
 Sponsoring Org.:
 USDOE National Nuclear Security Administration (NNSA)
 OSTI Identifier:
 1413439
 Report Number(s):
 SAND201713271
659371
 DOE Contract Number:
 AC0494AL85000
 Resource Type:
 Technical Report
 Country of Publication:
 United States
 Language:
 English
 Subject:
 58 GEOSCIENCES
Citation Formats
Poppeliers, Christian. The use of multiwavelets for uncertainty estimation in seismic surface wave dispersion.. United States: N. p., 2017.
Web. doi:10.2172/1413439.
Poppeliers, Christian. The use of multiwavelets for uncertainty estimation in seismic surface wave dispersion.. United States. doi:10.2172/1413439.
Poppeliers, Christian. 2017.
"The use of multiwavelets for uncertainty estimation in seismic surface wave dispersion.". United States.
doi:10.2172/1413439. https://www.osti.gov/servlets/purl/1413439.
@article{osti_1413439,
title = {The use of multiwavelets for uncertainty estimation in seismic surface wave dispersion.},
author = {Poppeliers, Christian},
abstractNote = {This report describes a new singlestation analysis method to estimate the dispersion and uncer tainty of seismic surface waves using the multiwavelet transform. Typically, when estimating the dispersion of a surface wave using only a single seismic station, the seismogram is decomposed into a series of narrowband realizations using a bank of narrowband filters. By then enveloping and normalizing the filtered seismograms and identifying the maximum power as a function of frequency, the group velocity can be estimated if the sourcereceiver distance is known. However, using the filter bank method, there is no robust way to estimate uncertainty. In this report, I in troduce a new method of estimating the group velocity that includes an estimate of uncertainty. The method is similar to the conventional filter bank method, but uses a class of functions, called Slepian wavelets, to compute a series of wavelet transforms of the data. Each wavelet transform is mathematically similar to a filter bank, however, the timefrequency tradeoff is optimized. By taking multiple wavelet transforms, I form a population of dispersion estimates from which stan dard statistical methods can be used to estimate uncertainty. I demonstrate the utility of this new method by applying it to synthetic data as well as ambientnoise surfacewave crosscorrelelograms recorded by the University of Nevada Seismic Network.},
doi = {10.2172/1413439},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2017,
month =
}

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