oa New Generation Seismic (NGS) Acquisition with a Land Seismic Super Crew

In 2008, Petroleum Development Oman implemented New Generation Seismic to fulfil technical<br>objectives while taking into account economical and efficiencies factors. The technical objectives are to<br>obtain properly sampled and wide azimuth (WAZ) seismic for both shallow and deep objectives in<br>support of current and future exploration and development projects. The sampling requirements to<br>meet these objectives translate into receiver grids of 12.5 to 25m in-line by 200m maximum cross-line<br>and full source VP grids no less than 400 VP/km2 (for example 50x50 m or 25x100 m). The WAZ<br>requirement is to provide a minimum offset in all azimuths of at least the depth to deepest perceived<br>target (typically 4km or greater). When combined, these sampling and width requirements result in<br>New Generation Seismic with a fold exceeding 4000 in 25x25m bins suitable for full Common Offset<br>Vector processing and full azimuth interpretation and quantification of azimuthally varying seismic<br>attributes. Further, full top to bottom and high quality imaging is realized for both very shallow and<br>very deep targets.<br>In order to efficiently acquire large areas, 10000+ km2, with over 400 VP/km2 two super crews were<br>introduced. One super crew with a capacity of 25,000 channels (12 Geophone per station), and 16<br>vibrators, and the other with 16,500 channels (also 12 Geophones) and 16 vibrators. These super<br>crews enable efficient operations with block widths in the range of 30+ km (a 30% efficiency<br>improvement), and also fully productize dual methods of short sweep length simultaneous sourcing<br>using both slip-sweep and distance separation (a 300% productivity improvement). In addition, the<br>super crews now operate 24 hours per day (another 50% productivity improvement) and are equipped<br>with the latest high channel count and high productivity SN428 recording system and VE464 vibrator<br>electronics. While the throughput of these super-crews is approximately a factor 6 improved, the<br>number of people needed in the field is a much more modest increase of approximately 50%.<br>As fully implemented in 2008, these super crews are consistently meeting PDO expectations and are<br>setting world record productivity numbers. Daily average VP rates exceeding 13000 are common.<br>Considering PDO’s minimum VP density of 400 VP/km2 these productivity numbers translate into an<br>average production of 30+ km2 surface area per day per crew.