Edit Merge Script for the Specific Down-hole Survey

Since several survey details are likely to vary from one bore hole to the next, you must edit a few lines of the file, Merge. These lines are near the top of the file and are reproduced below. The boxed values will need to be changed.

#set -x
#...define parameters YOU MUST DEFINE THESE FOR EACH NEW SURVEY
# SINCE IT IS LIKELY THAT THE NUMBER OF RECORDS
# WILL VARY WITH EACH SURVEY !!!!
odmin=01

evmin=02


# eklmax=(odmax-1)/2
eklmax=`bc <<END
($odmax-1)/2
END`
echo $eklmax
# oklmax=eklmax+1
oklmax=`bc <<END
($eklmax+1)
END`
echo $oklmax
#shaping filter parameters (bshp)
tmin=0.
tmax=0.1
npf=360
stab=.0001
#polarity file definitions

The record numbers in the GeoLogan97 survey run from 1 through 146. The odd numbered records are 1, 3, 5, . . .145. Thus, odmin=01 and odmax=145. You will have to edit Merge to change odmax from 163 to the current value of 145. Similarly, the even numbered records run from 2, 3, 4, . . . 146. You will have to change evmax to 146. In the GeoLogan97 survey, the odd numbered records had a source azimuth of $90^{o}$ and the even numbered records a source azimuth of $270^{o}$. Thus, the variables az90 and az270 will have to be changed to match the current survey. Set az90=1 and az270=2. These two values affect the order of subtraction between the two polarities of the source, and hence the final sign convention of the enhanced data. Finally, the prefix for the GeoLogan97 data is “L”, not “w”. Make the change so that PRFX=L. Depending on your views, you may also wish to modify the shaping filter parameters (see program bshp). The shaping filter corrects for triggering variations and source blow amplitude variations which might be mistaken for down-hole geologic effects, were it not for our monitoring of the source with a stationary reference phone.