Pluto Model

Shot Records

BP performed a fourth order finite differencing modeling code on the padded velocity model. Madagascar can easily be used to display and manipulate the data. The script pluto/shot/SConstruct presented in table 4 fetches the dataset and constructs the RSF formatted dataset plutoShots.rsf.

As written this script outputs two images; figure 3 shows the Pluto zero offset shot gather while figure 4 shows shot 30.

from rsf.proj import *

# Fetch Files from repository
Fetch("P15shots150f_endon_0ph-1stHlf.SEGY","pluto")
Fetch("P15shots150f_endon_0ph-2ndHlf.SEGY","pluto")

# Convert Files to RSF and append headers
files = ['P15shots150f_endon_0ph-1stHlf.SEGY','P15shots150f_endon_0ph-2ndHlf.SEGY']
counter=0  #o2=360
for item in ['rsf1','rsf2']:
    Flow(item,files[counter], '''
            segyread tape=$SOURCE | put  
            o1=0 o2=0 o3=0 d2=.02286 d3=.0457 n2=350 n3=347  
            label1=Time  label2=Position unit1=s unit2=km 
            label3=Shot''',stdin=0)
    counter = counter + 1

# Concatinate Files
Flow('plutoShots',['rsf1', 'rsf2'],'''
            cat ${SOURCES[0:2]} axis=3''',stdin=0)

# Plotting Section
Result('zero','plutoShots','''window $SOURCE  min2=0 max2=0 size2=1 | 
               grey  color=I gainpanel=a label2=Position X unit2=km
               title=Zero Offset Data label2=Distance''')
Result('shot30','plutoShots','''window $SOURCE  min3=1.371
               max3=1.371 size3=1 | grey color=I wantframenum=y  
               gainpanel=a title=Shot # 30 label2=Offset''')
End()

Table 4. Scons script that generates RSF formatted pluto shot data

zero
Figure 3. Zero offset data for Pluto synthetic dataset

shot30
Figure 4. Shot 30 of Pluto dataset

Shot data should be formatted as shown in table 5. Again both metric and standard units are shown.

Standard
n1=1126	d1=.008	o1=0	label1=Z Depth	unit1=s
n2=350	d2=75	o2=0	label2=X	unit2=ft
n3=694	d3=150	o3=0	label3=Shot
Metric
n1=1126	d1=0.008	o1=0	label1="Depth"	unit1=s
n2=350	d2=0.02286	o2=0	label2="Position"	unit2=km
n3=694	d3=0.0457	o3=0	label3="Shot"

Table 5. Header information for Pluto velocity models

Pluto Model