Subsalt Imaging

Truly broadband data bring high resolution and layer differentiation. The reduced sidelobes create sharper wavelets for greater clarity. The six octaves of data recorded by BroadSeisTM provide high resolution shallow data as well as low frequencies for subsalt penetration. In order to achieve sufficient bandwidth in areas where high frequencies are limited, it is necessary to extend the low frequencies. Lower frequencies are affected less by attenuation, and provide greater accuracy and stability for seismic inversion.

Brazil - Santos Basin

Toggle to compare: Conventional Conventional with GWE BroadSeis

In this example from the fast track PSDM processing from CGG's Santos Basin multi-client data, the broad bandwidth from BroadSeis provides improved pre-salt imaging over conventional surveys, even with GWE deghosting.

Conventional marine streamer acquisition lacks sufficient signal-to-noise ratio in the 2-7 Hz bandwidth due to streamer depth, streamer tow noise, source array configuration, source depth and source bubble. Using BroadSeis we routinely record frequencies down to 2.5 Hz, providing three octaves of data below 20 Hz.

Good signal-to-noise ratio data at low frequency need to be recorded, Deghosting techniques that only boost the low frequencies will not provide the same strength of signal as truly broadband data that have been recorded. Due to the proprietary curved shape of BroadSeis streamers, the average tow depth is significantly deeper than that of other acquisition geometries, which increases the signal-to-noise both by being below the swell and due to the steeper slope of the receiver ghost notch. In addition, Sentinel solid streamers are renowned for their low-noise properties, especially at low frequencies, and have been shown to be 10-15 dB quieter at 5 Hz than gel streamers in vibration tank tests.

Gulf of Mexico

GoM salt flood 20 Hz Salt Flood RTM showing improved illumination of the subsalt.

Angola BroadSeis

Offshore West Africa - Angola

We see the same improvements in data quality on the Eastern side of the Atlantic. In this example from our multi-client data in Block 21 there is clear imaging of the base salt and pre-salt structures as well as fine definition of the post-salt.

In addition to extending the low frequencies subsalt imaging is often enhanced by acquiring long offsets and increasing the range of azimuths. The improved sampling enhances illumination as well as improving noise and multiple attenuation.

Improve Pre-Salt Imaging with Variable-Depth ...

Thomas Rebert | Ronan Sablon | Nicolas Vidal | Pierre Charri...
©2012 SEG

Broadband, long-offset, full-azimuth, stagger...

Fabrice Mandroux | Beng Ong | Chu-Ong Ting | Sabaresan Mothi...
©2013 EAGE

Staggered marine acquisition design for compl...

Fabrice Mandroux | Chu-ong Ting | Bob Montgomery | Alexandre...
©2013 SEG
Offshore - StagSeis


Illuminate subsalt and basalt like never before. Reduce exploration and production risk. Ultra long-offset, full-azimuth broadband for unparalleled interpretation.
Offshore - Low Frequency Recording

Ultra-Low Frequency Recording

See below salt and basalt. Build better reservoir models. Record useful data down to 2.5 Hz with Sentinel.
Multi-Client Data - Gabon


Over 25,000km2 PSDM seismic data available as part of a complete geoscience package including regional geological analysis in this prospective area.
Offshore - BroadSeis


Broadest bandwidth, best low frequencies deliver accurate models for better decisions. Choose BroadSeis at all stages from exploration to production.

Offshore - BroadSeis Interp

BroadSeis Interpretation

Confident interpretation from clear differentiation between sedimentary packages and better facies discrimination with the ultra-low frequencies delivered by BroadSeis.
Multi-Client Data - Brazil Presalt

Brazil Pre-Salt

Extensive modern BroadSeis pre-salt library offshore Brazil, including Santos and Campos Basins. Assess your options. Make informed decisions.
Offshore (Marine)


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