Nonstretch moveout correction of long-offset multichannel seismic data for subbasalt imaging: Example from the North Atlantic

• Published in: GEOPHYSICS
• Main Authors: Masoomzadeh, Hassan, Barton, Penny J., Singh, Satish C.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2010
• Subjects: 02 - Geodynamics; Geophysics and Tectonics; North Atlantic
• Online Access: http://eprints.esc.cam.ac.uk/2062/; http://eprints.esc.cam.ac.uk/2062/1/Masoomzadeh_et_al._-_2010_-_Nonstretch_moveout_correction_of_long-offset_multi.pdf; http://geophysics.geoscienceworld.org/cgi/content/abstract/75/4/R83; https://doi.org/10.1190/1.3443579

We have developed a pragmatic new processing strategy to enhance seismic information obtained from long-offset multichannel seismic data. The conventional processing approach, which treats data on a sample-by-sample basis, is applied at a coarser scale on groups of samples. Using this approach, a reflected event and its vicinity remain unstretched during the normal moveout correction. Isomoveout curves (lines of equal moveout) in the time-velocity panel are employed to apply a constant moveout correction to selected individual events, leading to a nonstretch stack. A zigzag stacking-velocity function is introduced as a combination of segments of appropriate isomoveout curves. By employing a zigzag velocity function, stretching of key events is avoided and thus information at far offset is preserved in the stack. The method is also computationally cost-effective. However, the zigzag stacking-velocity field must be consistent with target horizons. This method of horizon-consistent nonstretch moveout has been applied to a wide-angle data set from the North Atlantic margin, providing improved images of the basement interface, which was previously poorly imaged.