Marine acquisition geometry
![]() | |
Series | Investigations in Geophysics |
---|---|
Author | Öz Yilmaz |
DOI | http://dx.doi.org/10.1190/1.9781560801580 |
ISBN | ISBN 978-1-56080-094-1 |
Store | SEG Online Store |
Old 3-D surveys were conducted using a single receiver cable and a single source array. This is known as line shooting. A modern marine 3-D survey involves shooting a number of closely spaced parallel 2-D subsurface lines. This is achieved by using multicables and multi-source arrays. While some surveys are known to have been recorded using 12 cables, the more common configuration is 4-8 cables with dual source arrays. The recording geometry for multicable marine surveys is similar to that of the multireceiver line recording geometry — known as swath shooting, used in land, shallow-water, and transition-zone surveys. Figure 7.1-2 shows marine recording geometry that involves 12 cables and dual source array. Since each source-cable combination yields midpoint locations along one subsurface line, this recording geometry yields 24 subsurface lines, simultaneously. As a result, multicable recording increases the productivity in acquisition by greatly reducing the time in the field. Nevertheless, issues with multicable recording arise in relation to large variations of source-receiver azimuths in relation to velocity estimation, migration and amplitude variation with offset analysis.
See also
- Migration aperture
- Spatial sampling
- Other considerations
- Cable feathering
- 3-D binning
- Crossline smearing
- Strike versus dip shooting
- Land acquisition geometry