Marine seismic surveys use sound (acoustic) energy to map geological structures under the seabed. Seismic surveys are an essential part of offshore exploration to obtain information on the depth, position, and shape of underground geological formations that may contain oil and natural gas.
Before conducting a marine seismic survey, the operator must first undertake a thorough Environmental Assessment (EA), which reviews potential environmental impacts in the proposed survey area and considers feedback from the public and stakeholders. The EA is reviewed by the federal Department of Fisheries and Oceans (DFO), the Department of Environment and Climate Change, and must be approved by the Canada-Newfoundland and Labrador Offshore Petroleum Board (C-NLOPB) or the Canada-Nova Scotia Offshore Petroleum Board (CNSOPB) before a survey can proceed.
Measures that must be considered include:
- Minimizing the sound energy employed to achieve the purpose of the survey.
- Gradual start-up of a sound source to allow marine mammals, sea turtles, and other species to move away.
- Immediate shut down of sound sources if marine mammals or sea turtles listed as endangered are observed within 500 metres of the sound source.
- Use of qualified observers to monitor survey operations.
- Avoidance of known, critical habitats specified under species-at-risk legislation.
- Avoidance of known species migration routes, spawning areas, and habitats.
CAPP members continue to fund research related to seismic surveys and potential impacts and mitigations to help further the body of knowledge available in this area.