New First Break Article on Separated Wavefields
PGS Chief Scientist Andrew Long's article in the June issue of First Break considers present and future opportunities of using separated wavefield data to illuminate, resolve, characterize and monitor reservoir properties and production in various marine settings.
There are some fundamental shortcomings in the traditional marine broadband seismic pursuit of uniform amplitudes over a large range of temporal frequencies, and deghosting achievable via many platforms contributes only modest amplitude improvements at very low and high frequencies.
When attention turns to the pre-stack domain the benefits of dual-sensor GeoStreamer® data and separated wavefields become more evident, particularly with respect to high fidelity reservoir characterization and reservoir monitoring.
The use of combined wavefields in wave theoretic imaging solutions extends the opportunities for enhanced subsurface illumination and resolution, and enables shallow reservoir characterization and efficient reservoir monitoring solutions not conceivable using conventional hydrophone-only seismic data.
When a larger range of spatial frequencies are also recovered using both explicit and implicit wave equation inversion solutions, 'broadband' marine seismic with separated wavefields clearly encompasses far more than the temporal resolution benefits considered a decade ago.
Read the full article here.
Schematic illustration of the up-going ('P-UP') and down-going ('P-DWN') pressure wavefields that combine to yield the total pressure ('P-TOT') data recorded by hydrophone-only streamers. Note the dynamic sea-surface effects inescapably embedded within all arrival times on P-DWN (and therefore, P-TOT) data. The dual-sensor wavefield separation applied to GeoStreamer data enables perfect isolation of the P-UP data
Click on the infographic for full screen view