The effects of marine seismic acquisition in a coral reef environment: results from a multi-disciplinary monitoring program at Scott Reef, Western Australia

Abstract

In September 2007 Woodside Energy Ltd, as operator of the Browse LNG Development , conducted the Maxima three-dimensional marine seismic survey (Maxima) at Scott Reef, a shelf-emergent coral atoll located in the Indian Ocean approximately 425 km north of Broome, Western Australia Implementation of the survey followed extensive state and Commonwealth environmental approvals processes that began more than 12 months earlier. The survey drew regulator and stakeholder attention, with focus on the uncertainties associated with predicting impacts on Scott Reef marine environment as a result of exposure to airgun noise emissions. Ministerial conditions for approval of the survey concluded that significant impacts were unlikely (Woodside 2008), but required Woodside to address the inherent uncertainties through implementation of a suite of research and monitoring activities prior to, during and after Maxima. Most were completed in on site Scott Reef as part of a field verification study, conducted in advance of the full data acquisition phase of Maxima. These monitoring studies showed that the actual effects of exposure to an airgun array were lower than predicted and established new sound exposure thresholds.