## start with the location of the closest station
data(GH, package='RSEIS')
g1 = GH$pickfile
data(VELMOD1D, package='RSEIS')
vel= VELMOD1D
STAS = GH$pickfile$STAS
w1 = STAS$phase == 'P'
initz = 6
t0a = GH$pickfile$LOC$sec
XY = XYSETUP(STAS, c(STAS$lat[w1],STAS$lon[w1], initz, STAS$sec[w1]-t0a ) , vel )
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