Page 168 - Acquisition and Processing of Marine Seismic Data

TABLE 2.17 Example of General Acquisition
Parameters List and Tolerance Values for a 3D Survey

Parameter Nominal Value Tolerance Parameter Nominal Value Tolerance
General Survey size 2412.60 km 2 N/A Streamer depth 8 m 1m
Total prime line 4810.60 km N/A
length Minimum 120 m 10 m
offset
Estimated survey 80–90 days N/A
time Number of birds 12 acoustic N/A
per streamer bird
Acquisition 4–4.5 knot N/A 16 compass
speed bird
Shooting 45.16° N/A Number of 12 acoustic N/A
azimuth acoustic units per bird
streamer 8 CMX
Distance between 400 m N/A
sail lines Number of 16 (every N/A
steering devices 500 m)
Number of sail 172 N/A
per streamer
lines
Number of rGPS 2 paravanes N/A
Number of total 2752 N/A
pods 6 source
CMP lines
strings
Run-in 4000 m N/A 8 tail buoys
Run-out 4000 m N/A Recording Record length 10,000 ms N/A
Bin size 6.25 m 25 m N/A Sample rate 2 ms N/A
Optimum fold 80 N/A Total number of 192,424 N/A
shot points
Geodesy Ellipsoid WGS84 N/A
Data format SegD rev01 N/A
Semi major axis 6,378,137.0000 N/A
Trace summing N/A N/A
Inverse flattening 298.2572235630 N/A
Source Number of 2 N/A
Eccentricity 0.081819190843 N/A source arrays
Projection UTM N/A Number of 3 per source N/A
strings
Scale factor 0.999600000000 N/A
3
Total volume 3200 in per N/A
Central meridian 063°00 0.0000 00 N/A
0
array
False easting 500,000.0000 N/A
Source 50 m (25 m flip- 10%
False northing 10,000,000.0000 N/A separation flop)
UTM zone 41S N/A String 8m 10%
separation
Layout Type of Solid N/A
streamers Source 16 m 8m 10%
dimension
Number of 8 8000 m N/A
streamers Source depth 6 m 0.5 m
Streamer 100 m N/A P-P pressure 112.5 bar-m 5%
separation
PBR ratio 28.6 5%
Number of 640 per N/A
channels streamer Air pressure 2000 psi 10%
Gun timing N/A 1ms
Group interval 12.5 m N/A
Continued