A 3-D Seismic Prospecting Integration Solution in a Complex Mountainous Region, Western Qaidam Basin

Summary The Yingxiong Mountains are located in the western Qaidam Basin of China, and the potential for oil reservoirs in this area is significant. Due to the rugged terrain and common inclement weather in the area, there are a number of challenges and difficulties for seismic exploration, so this area was once considered to be a “forbidden zone” for seismic prospecting. 2-D seismic exploration in this area has been attempted since 1995, but the signal-to-noise ratio (S/N) of the seismic data has been poor, owing to the rugged terrain and complex near-surface structure. With the on-going advancement of geophysical techniques, and upgrades to operational equipment in recent years, the data quality has been continuously improved using 2-D wide-line, and the outline of structures can now be interpreted. In 2010, seismic exploration led to the discovery of a big oil reservoir in this area. As a continuation of that work, high-density, 3-D seismic acquisition techniques were employed for the first time in the Yingxiong Mountains in 2011. The quality of the 3-D seismic data has made significant progress using: shot and geophone array joint suppressing noises, high density sampling indoor de-noising, high fold stack, high density pre-migration, and a mark interface verifying static correction. According to detailed 3-D seismic data interpretation, the Yingxiong Mountains oil field may account for over a hundred million tons of oil, and successful drilling in this area would constitute one of the most successful complex mountainous 3-D seismic prospecting projects.