2009 Honorary Lecturer Pacific South | Andrew S. Long Petroleum Geo-Services (PGS)
Perth, Australia Multi-azimuth and Wide-azimuth Seismic: Foundations, Challenges, and Opportunities | | Abstract  As our industry enters the era of declining reserves replacement and increased exploration in areas affected by challenges to seismic imaging, interest is rapidly turning to the acquisition and processing of complementary source-receiver azimuths. Some proponents now equate the progression from "standard" 3D to multi-azimuth (MAZ) and wide-azimuth (WAZ) 3D seismic as being equivalent to the progression of the industry from 2D to 3D seismic! While survey cost has historically been a high-profile issue, the pursuit of efficiency gains has stimulated innovations in the execution of MAZ and WAZ seismic. What really matters is that both MAZ and WAZ applications to towed streamer seismic deliver a remarkably robust attenuation of complex noise and multiple events, and the return on investment can be demonstrably justified. Now that a strong catalog of case studies exists, backed by advances in 3D modeling confidence, it is possible to evaluate all geophysical issues relevant to MAZ and WAZ seismic with an objective eye. Case examples from several major operators and service companies are presented from the perspective of presurvey objectives versus postsurvey learnings. Consideration is given to the many challenges throughout the southern Asia-Pacific region, including exploration and production targets affected by carbonates, basalts, and complex overburden structures. Particular attention is given to the issue of seismic wavefield scattering and how MAZ and WAZ geometries can address complex seismic multiple and noise problems. | | | | | | |
