The ObliQ sliding-notch broadband acquisition and imaging technique optimizes the recorded bandwidth of the seismic signal by combining slant-streamer acquisition with a proprietary deghosting methodology and a newly developed broadband seismic source.
Because the cable depth of the ObliQ technique is variable and increases from the near offset to the farthest offset, it is possible to determine and select the minimum and maximum cable depths in the survey design to optimize the recorded bandwidth and meet the geophysical objectives of your survey. In surveys that use the ObliQ technique, streamer depths range from 5 m to 50 m—a wider selection of depths than is available in conventional acquisition.
The ObliQ technique works by integrating notch diversity with a single-streamer deghosting workflow based on spectral reconstruction.
Cables are towed at a slant with a shallow near end and a deep far. Spread stability is maintained through the use of the Q-Fin marine seismic streamer steering system and the hydrophones are engineered to function without distortion at these depths.
Single-streamer deghosting narrows and reduces the depth of the receiver notch, or notches, depending on tow depth.
When used with the Delta calibrated marine broadband seismic source, notch diversity on the source side is improved because the airguns are positioned at variable depths.
Enabled by the Q-Marine point-receiver marine seismic system, the ObliQ technique can be employed with all types of surveys, from linear sail-line acquisition geometries including narrow azimuth (NAZ) and wide-azimuth (WAZ), to curved sail-line acquisition geometries including Coil Shooting single-vessel full-azimuth acquisition and Dual Coil Shooting multivessel full-azimuth acquisitions. The combination of broad bandwidth with the Dual Coil full-azimuth, long-offset acquisition is particularly advantageous for imaging below complex structures such as subsalt and sub-basalt.
With all of these survey types, the ultralow-frequency system response of Q-Marine technology ensures the high-fidelity recording of the bandwidth extension towards the low frequencies enabled by the ObliQ technique.