Effective monitoring of nearshore seismic surveys off Sakhalin and mitigation of sound exposure for a feeding whale population
Event name: 80th EAGE Conference & Exhibition 2018 Workshop Programme
Session: WS14: The Effect of Seismic Surveys on the Marine Environment
Publication date: 15 June 2018
Info: Extended abstract, PDF ( 250.43Kb )
Price: € 20
The northeastern shelf of Sakhalin Island, Russian Federation, is an important feeding ground of a critically endangered population of gray whales (Eschrichtius robustus) which convene annually in the region near the mouth of Piltun lagoon. In 2010 and again in 2015, Sakhalin Energy Investment Company conducted repeat (4D) seismic surveys to characterize changes to the subsurface from hydrocarbon production at the two platforms, required for efficient positioning of new wells; the original 3D seismic data had been acquired in 1997. Considerable effort went into the development for the 2010 seismic survey of a Monitoring and Mitigation Plan (MMP) that would recognize not just the necessity of preventing exposure of a critically endangered foraging population of gray whales to damaging or behaviourally interfering seismic pulse levels, but also the importance of collecting high quality acoustic and visual monitoring data to be used in studies of potential effects. This resulted in an effective framework for sound exposure estimation, measurement and mitigation and a highly structured shore based visual observation program capable of providing robust data on distribution and behaviour of the animals. Measured revisions and enhancements for the 2015 seismic survey MMP addressed some shortcomings of the earlier version for greater efficacy.