The famed explorer Roald Amundsen, who claims to have visited both poles, once noted, “Adventure is just bad planning.” With this in mind, oil companies wishing to explore in the Arctic are taking special precautions.

At the recent Arctic Technology Conference in Houston, Kevin Williams, manager of exploration operations for Chevron Canada Resources, discussed the need for especially careful planning during a talk titled, “Sirlauq 3-D: Beaufort Sea Marine Seismic.” The talk discussed Chevron’s successful 3-D survey of its exploration license 481 in the Canadian Beaufort Sea during the summer of 2012.

Chevron, which has been active in Canada for 75 years, has two licenses in the Beaufort Sea. It owns 60% in Exploration License 481, the subject of the survey. The survey area is 120 km (75 miles) north of Hershel Island in water depths of 800 m to 1,800 m (2,625 ft to 5,905 ft). The area experiences only four to eight weeks of open water per year.

With this constraint in mind, the company executed a strategy to account for as many issues as possible. This started with an environmental assessment, which included consultation with local communities as well as planning for marine mammal and seabird mitigation if necessary. It also considered search and rescue issues.

“This became a significant issue if someone got injured or sick,” Williams said. “We couldn’t get them off.” Through coordination with the Coast Guard, Canadian Search and Rescue, and Shell, Chevron was able to put together an independent search and rescue team consisting of three boats and two helicopters. All of the assets were in the rescue position for the entire survey.

Additionally, there are no deepwater ports and very little infrastructure in the region, so the company had to plan to shoot the entire program with no refueling.

Planning the survey itself was a bit more challenging. The team had to take the operating window into consideration. “We asked for ice forecasts and discovered that ice forecasters don’t like to give ice forecasts,” he said. “But we evaluated data from 2002 to 2011. Based on that, the weather window averaged 55 days per year of open water. Bad years were only 30 days. And there was one year, 2003, where the block was never free from ice.”

This added complexity to the survey plan. The area is 100 km (60 miles) in the strike direction and 30 km (15 miles) in the dip direction. The dip direction is more desirable from a resolution standpoint. But it would take more time to shoot.

“We would have gotten better resolution in the dip direction, but production and efficiency were maximized in the strike direction,” Williams said, adding that shooting in the strike direction shaved an estimated 16 days off of the overall program.

The team got lucky – 2012 had one of the longest weather windows in many years. Once the main survey was shot, it was able to reshoot some of the lines in dip direction and record data during the turns, he said.

Best practice learnings from the survey include:

  • Beginning front-end loading early;
  • Engaging early, regularly, and openly with stakeholders and contractors;
  • Soliciting input from subject matter experts; and
  • Preparing multiple designs.

“We had zero safety or environmental issues and got 3,700 sq km (1,430 sq miles) of high-quality multi-azimuth seismic data,” Williams said.

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