b'Geophysics in the SurveysNewsGeological Survey of Victoria: Otway Basin Airborne Gravity Survey - data acquisition completeThe Geological Survey of Victoria (GSV)and included flying a common repeatgravity imagery in south west Victoria, has completed the data acquisitionline and a test area, a block of 11 lines bycompared with pre-existing data. phase of the Otway Basin Airborne10 line-km, to verify that the two systemsQualitative interpretations of the data will Gravity Survey in south west Victoriawere collecting equivalent data. infill and complement seismic datasets (Figure 1). The survey is a key componentThe GSV is pleased to report no accidentsin the Otway Basin, particularly over the of the Victorian Gas Program, which isor incidents associated with the survey,three-nautical mile zone around the a comprehensive program of scientificwith extensive community consultationOtway coast where very little geological research and related activities to assessundertaken to facilitate flying near dairydata has been acquired previously.the potential for further discoveries offarms, racehorse stables and protectedThe survey data will be released to the onshore conventional gas and offshoremarine mammal areas including whalepublic through the Earth Resources gas in Victoria. nurseries. website (www.earthresources.vic.gov.CGG Aviation (Australia) Pty Ltd flew 32During the data acquisition phase a totalau) in the first half of 2019. For more 000 line-km of Full Spectrum Falconof 24 crew spent time in Warrnambool,information on the Victorian Gas Program gravity gradiometry and magnetic dataand the survey contributed approximatelyvisit www.earthresources.vic.gov.au/at 500 m line spacing and 150300 m$430 000 to the local economy. earth-resources/victorian-gas-program terrain clearance between August 2018or email vgp@ecodev.vic.gov.au.and January 2019. The survey was flownThe survey has resulted in the largestSuzanne Haydon using two fixed-wing aircraft (singleairborne gravity dataset ever collectedGeological Survey of Victoria engine onshore, twin-engine offshore)in Victoria and provides superior qualitySuzanne.Haydon@ecodev.vic.gov.auFigure 1.Map showing preliminary free air gravity data from the Otway Basin Airborne Gravity Survey (pink = high, blue = low).APRIL 2019 PREVIEW 24'