Geophysical company CGG Services (Australia) Pty Ltd (CGG) proposes to acquire a multi-client three-dimensional (MC3D) marine seismic survey (MSS) on the North West Shelf (NWS) offshore of Western Australia (WA).
The CGG Davros Phase II MC3D MSS EP (NOPSEMA Ref: 3093) was accepted by NOPSEMA on 9 February 2016 and covered a smaller area (1,693 km2). Due to the change in the survey scope in early 2017, the scope of the EP has been revised to assess the potential impacts and risks for the larger survey area, now referred to as the “Davros Extension MC3D MSS”.
The Davros Extension MC3D MSS comprises a survey acquisition area of approximately 8,072 km2. The Davros Extension MC3D MSS includes two operational area buffers around the survey acquisition area. The smaller operational buffer area of 9 km is for sail line run-ins and run-outs (required to obtain full fold coverage), soft-start procedures, streamer deployment/retrieval and maintenance, and the larger operational buffer of 15 km is for seismic vessel manoeuvring (line turns). The spatial extent of the largest operational area (15 km) is 15,289 km2 and is located entirely within offshore Commonwealth waters within the North-west Marine Region (NWMR). The Davros Extension MC3D MSS and 15 km buffer area includes 21 exploration permits, 26 production licences, 5 retention leases, and adjacent open acreage areas.
The Davros Extension MC3D survey area is located approximately 54 km north of Dampier and approximately 180 km north-west of Port Hedland, at its closest points to the mainland.
The commencement date of the Davros Extension MC3D MSS is yet to be decided. The duration of the activity is a maximum of 150 days, and will be conducted between the beginning of March 2018 and end of June 2020, with avoidance of the period from beginning of July to end of September. The 150 day estimate is conservative and allows for some downtime due to weather, avoiding conflicts with other users and marine megafauna, and maintenance.