sigconvGR {RSEIS}

convolve for Ground roll

Description

convolve a set of spikes for extended ground roll. This is a special case of sigconv.

Usage

sigconvGR(wigmat, wavepulse, dt)

Arguments

wigmat

matrix of traces with spikes

wavepulse

wavelet

dt

sampling interval

Details

This is similar to the sigconv program but it assumes that the ground roll is extrened in time and space as the wave expands.

Value

Matrix, waveforms

Note

the program spreads the sinusoidal wavelet along a band to simulate ground-roll head wave noise.

Author(s)

Jonathan M. Lees<[e-mail]>

See Also

wiggleimage, symshot1, genrick, sigconv

Examples

S1 <- symshot1()
dt <- S1$dt
###########    these are the reflections S1$GRrec

d <- dim(S1$smograms)
G1 <- matrix( rep(0, length=d[1]*d[2]), ncol=d[2], nrow=d[1])

###   these are the refractions S1$THEORY$trefrac
p <- round( S1$THEORY$trefrac[1,]/S1$dt );
G1[cbind(p , 1:d[2])  ] <- 1


#### plot the spikes
wiggleimage(0.1*G1, dt = -S1$dt, dx = S1$x, col = "black")

grlen <- floor(.6/dt)
fgr <- 10
tape <- applytaper( rep(1, grlen), p = 0.2)
tgr <- seq(from=0, by=dt, length=grlen)
siggr <- tape*sin(2*pi*fgr*tgr)

##############  convolve the wavelet with the set of spikes
H1 <- sigconvGR(G1, siggr, dt)

############  plot
wiggleimage(0.1*H1, dt = -S1$dt, dx = S1$x, col = "black")