brune.search: Search for Brune fit to displacement spectrum In RSEIS: Seismic Time Series Analysis Tools

Description

Model of the spectrum of a seismic arrival. Uses Brune's Model.

Usage

 `1` ```brune.search(infreq, inspec, f1, f2, omega0, fcorn, tstar0, gamma) ```

Arguments

 `infreq` vector of frequencies `inspec` spectrum `f1` low frequency, Hz `f2` high frequency, Hz `omega0` initial starting low frequency asymptote `fcorn` initial starting corner frequency `tstar0` initial starting t* `gamma` initial starting gamma

Details

see paper by Lees and Lindley

Value

list(omega0=omega0,tstar0=tstar3[3] , fc=fcorn, alpha=0, gamma=gam3[3])

 `omega0` low frequency asymptote `fc` corner frequency `tstar0` t* `gamma` gamma `alpha` alpha parameter `chisqrd` chi-squared misfit over region of fitting

Author(s)

Jonathan M. Lees<jonathan.lees.edu>

References

Lees and Lindley

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20``` ```data(CE1) #### set frequency range for modeling f1 <- 0.01 f2 <- 14.0 ## set up data and parameters amp <- CE1\$y len2 <- 2*next2(length(amp)) a <- list(y=amp, dt=CE1\$dt) Spec <- MTMdisp(a, f1=f1, f2=f2, len2=len2, PLOT=FALSE ) lspec <- Spec\$displ ### get initial estimate of parameters xc <- get.corner( Spec\$f , lspec, dt, f1, f2, PLOT=FALSE) jmod <- brune.search(Spec\$f, lspec, f1, f2, xc\$omega0, xc\$corn, xc\$tstar0, 2.0) ```