Southwest Gas, a subsidiary of Sinopec, had been actively developing a region north of Chengdu for many years. Previous seismic from this area had provided partial answers to the questions of reservoir characterization; however, better results were required for Southwest Gas to fully exploit its resources.
As early as 2000, Southwest Gas had begun to evaluate the potential for full-wave imaging techniques in the Chengdu region. After conducting several geophysical analyses and pilot tests, Southwest Gas moved to broad deployment of a full-wave solution. The deployment team involved Southwest Gas as the E&P operator, ION as the technology and imaging services provider, and BGP as the owner of the full-wave equipment and provider of field acquisition services.
Acquisition began in October 2004. BGP recorded the largest and most aggressive full-wave project on record. By focusing on operational details like survey design, sensor deployment, and source optimization, all with the full-wave strategy in mind, BGP recorded densely sampled data that has yielded spectacular results. The raw, pre-stack data showed significant improvement in signal-to-noise ratios.
GX Technology was awarded the contract for data processing and
interpretation and have applied a full suite of processing and interpretation steps. The resulting high-resolution seismic images help to resolve subtle properties within the reservoir zones, including an analysis of shear-wave splitting and fracture patterns. The combination of these data, made possible through an integrated approach to full-wave seismic survey design, acquisition, and processing, is allowing Sinopec to identify new, highly prospective drilling targets in the XinChang structure.
Local media headline: “Gas dragon rising from depths of Sichuan”
