2014 Honorary Lecturer

Pacific South

Sandeep Chandola

PETRONAS Carigali
Kuala Lumpur, Malyasia

Marine Seismic Acquisition: Expanding the possibilities

Abstract

Historically, towed-streamer marine seismic acquisition has been a compromise between the geophysical requirements and the operational constraints. For several years advancements in marine streamer acquisition were on enhancing productivity by towing a large number of steamers and on design improvements in streamers and air gun sources. With the increasing demand of high-quality seismic imaging of complex geology, the focus in the last decade has shifted to "tune" the survey for improved wavefield sampling, bandwidth, and illumination.

The advent of broadband streamer-acquisition techniques has arguably been one of the most important developments in geophysics in the twenty-first century. These techniques involve removal of the free-surface ghost present in the conventional flat-tow hydrophone data, using a combination of novel streamer design/configuration and proprietary data-processing techniques, to deliver a broadband signal. Equally important has been the evolution of multi-azimuth (MAZ), wide-azimuth (WAZ) and full-azimuth (FAZ) acquisition to improve the illumination of structurally complex targets through better samplings of the azimuths.

This presentation shall focus on the aspects considered key enablers for expanding the possibilities in marine streamer acquisition. The following acquisition techniques, currently available in the market, shall be covered in the presentation:

• Dual-sensor streamers
• Over-under streamers
• Variable depth streamers
• MAZ, WAZ and FAZ circular shooting
• Emerging trends (multi-sensor streamers, broadband circular shooting, etc.)