FloatSeis Dual Source™


FloatSeis DualSource™ service is mainly designed for exploration seismic surveys aimed to prospect deep-laying hydrocarbon traps and investigate their petroleum potential. It can also be applicable for regional surveys where basement, crustal layers and Moho boundary are relatively not deeply buried.


FloatSeis DualSource™ surveys are performed with simultaneously shooting by standard air gun array wide spread in a conventional CDP towed streamer surveys and by an extra specially tuned Low Frequency source. Energy emitted by standard air gun array is useful for towed seismic streamer records, while Low Frequency source energy is valuable for refracted waves recorded by GWL Seismobuoys™. Applying of Low Frequency source enables recording refracted waves on ultra-long offsets, thus increasing the total depth of an accurate velocity model building. Deblending processing technique helps to separate low and high frequency wave fields in such a manner that Low Frequency source has now influence on towed streamer data and vice versa.

To acquire FloatSeis DualSource™ dataset a FloatSeis™ field party based on an additional support vessel with an opportunity to mount onboard 20’ standard dry container and a seismic vessel with towed streamer and two seismic sources (standard air gun array + Low Frequency source) onboard are required.

Acquisition Technique:

  • Seismic vessel acquires data with a towed streamer and an additional Low Frequency source onboard;

  • GWL Seismobuoys™ are deployed simultaneously along seismic line to record ultra-long offset refracted data;

  • Low Frequency source allows the recording of refracted waves at ultra-long offsets;

  • Recorded offsets up to 90-120 km;

  • Recorded ultra-long offsets increase the total depth of a reliable velocity model

  • Target depth coverage (reliable velocity model) up to 18-20 km.


Low Frequency source is installed onboard the seismic vessel. No additional source vessel required.

As a result of FloatSeis DualSource™ survey ultra-long offset refracted wave dataset is acquired to build reliable velocity model up to 18-20 km depths with help of refracted wave data tomographic inversion. Obtained velocity model suits the best for towed streamer data migration and an accurate time to depth conversions.



А – CDP reflection data for seismic imaging;

B – FloatSeis™ data for reliable velocity model building for use in PSDM




FloatSeis DualSource™

Reliable Velocity Model

Target depths up to 18-20 km

Seismic Vessel with extra

Low Frequency Source onboard


FloatSeis™ Support Vessel