The growing need to control costs and compress the decision-making time frame has become an ever-pressing issue in every E&P cycle. This means that the provision of seismic data must be carried out in a cost-effective way, with reduced turnaround time as well as operational and environmental exposure. Simultaneously, acquisition and processing should be accomplished without compromising the data quality required to overcome the technical challenges in a given area.
WesternGeco has achieved this by delivering higher volumes of seismic data of better quality at a lower cost through the development of technologies that deliver optimum subsurface illumination and imaging while incorporating efficiency-enabling features. These technologies rely on efficient algorithms, parallel workflows and innovative techniques that provide high-quality answer products to the customers in a timely manner.
A seismic survey acquisition project in the offshore Angoche basin illustrates how WesternGeco successfully implemented these technologies over the Mozambique 5th licensing round blocks. In addition, this survey also covers open acreage areas to be awarded in future licensing rounds. Data were required quickly to support short-term exploration decisions as well as higher-resolution studies for subsequent appraisal and development activity. The 15,000-sq-km (5,792-sq-mile) broadband multimeasurement towed-streamer seismic survey was acquired and processed onboard the acquisition vessel. The high-standard prestack time migration workflow included multimeasurement 3-D receiver deghosting and wavefield reconstruction.
A high-quality accelerated interpretation-ready image cube was produced onboard within four weeks of the last shot point. This volume became the basis for confident interpretation and exploration decisions. Further improvements are expected via subsequent onshore processing, including additional source deghosting and depth imaging, with the opportunity to revisit archived field products for future high-resolution reprocessing objectives.