Arctic Efficiency - GeoStreamer Cracks the Weather Window Again
Two Arctic surveys last autumn clearly demonstrated the expanded operational envelope offered by GeoStreamer technology.
Two surveys carried out by PGS in the Arctic last autumn clearly demonstrated the expanded operational envelope offered by GeoStreamer technology. These dual sensor configurations are towed deeper than conventional arrays, benefiting from stiller waters, yet with broader bandwidth, and higher resolution.
The arctic season is remarkably short, and seismic vessels need to be able to take every advantage of the ice-free season. Arctic storms arrive quickly and whip the sea into choppy waves and fierce swells, with cumulative challenges of sea ice, icebergs, fog and North Atlantic storms.
From August to mid-September 2009 GeoStreamer vessel Atlantic Explorer mapped 1120 km2 offshore Greenland. The time saved by the GeoStreamer operation as a percentage of total equivalent survey with conventional streamers was 46%, operational statistics show. Weather downtime was just 3.5% of total survey time, over the 49 days of operation.
From mid-September to early November, Atlantic Explorer continued in the area with another GeoStreamer survey of 1025km2. By this time all conventional operations in the arctic had wound up their gear and headed south to avoid the swells. Despite the onset of the arctic winter, weather downtime was just 12%, and time saved compared to conventional tolerances was put at 50%. In reality, with conventional streamers this survey would never have been attempted, due to unlikelihood of completion and high cost.