Sigsbee2 Models

Infinite Surface Model

This data was prepared with the boundaries of the model extending forever; as such multiples are not created as a result of the model edges.

A SConsctuct script found at sigsbee/data2B/fs/ is presented in Table 8. This script translates the segy source data file and converts it into rsf format.

 #########################
 # Sigsbee 2B Shot Data  #
 #########################
from rsf.proj import *

#---- Define Variables and Filenames ---#
data = 'sigsbee2b_nfs.segy'

#------- Import Data ----------#
#- Uses ftp program Fetch
Fetch(data ,'sigsbee')

#-----  Convert Data ----------#
Flow('zdata tzdata ./dhead ./bdhead',data,
     '''
     segyread
     tape=$SOURCE
     tfile=${TARGETS[1]}
     hfile=${TARGETS[2]}
     bfile=${TARGETS[3]}
     ''',stdin=0)

# create sraw(t,o,s): o=full offset, s=shot position, t=time

Flow('ss','tzdata','dd type=float | headermath output="10925+fldr*150" | window')
Flow('oo','tzdata','dd type=float | headermath output="offset"         | window')
Flow('si','ss','math output=input/150')
Flow('oi','oo','math output=input/75')
Flow('os','oi si','cat axis=2 space=n ${SOURCES[1]} | transp | dd type=int')
Flow('sraw','zdata os',
     '''
     intbin head=${SOURCES[1]} xkey=0 ykey=1
     ''')
Flow('shotNfs2B','sraw',
     '''
     put
                           label1=Time       unit1=s
        d2=.02286 o3=0     label2=Offset     unit2=km
        d3=.04572 o3=3.330 label3=Shot-coord unit3=km |
     mutter half=false t0=1.0 v0=6000
     ''')

#-------- Plot Data --------#
Result('zero2Bnfs','shotNfs2B','''window $SOURCE min2=0 max2=0 size2=1
    | grey  pclip=98 color=I screenratio=1.5 gainpanel=a
    label2=Position label1=Time title= label3=  unit2=km unit1=s
    labelsz=3''')

Result('shot702Bnfs','shotNfs2B','''window $SOURCE n3=1 f3=70 |
    grey  pclip=99 color=I gainpanel=a wantframenum=y  unit1=s label1=Time
    label2=Offset unit2=km label3=Shot unit3=km title=
    screenratio=1.35 labelsz=3''')

End()

Table 8. Contents of data2B/nfs/SConstruct script.

Similar plots are produced for this model. Figure 7 shows an image of shot number 70 taken at 6.5 km into the model. Figure 8 displays the zero offset data acquired on this model.

shot702Bnfs
Figure 7. Shot 70 performed in Sigsbee 2B NFS model.

zero2Bnfs
Figure 8. Sigsbee 2B reflecting surface zero offset data, notice the decreased multiples from the free surface model

Sigsbee2 Models