Index of Gravity Surveys - Geoscience Australia

plotted by geographical features or air photos.‣ PHT – Positions scaled from air photographs.‣ SCA – Positions scaled from maps to 1/10 th of a minute of arc.‣ SRN – Positions determined using Short Range RadarNavigation.‣ SUR – Positions determined by optical surveying methods ormeasured on surveyed points.‣ TOS – Positions at a third order geodetic point, generally abenchmark.On/Off:Operator:Processor:Reliability:Indicates whether data were acquired:‣ On – on-shore.‣ Off – off-shore.‣ OnOff – both on and off shore.The organisation which commissioned the survey.The organisation that processed the survey data.Estimate of the overall reliability of the survey.‣ 0 – unreliable.‣ 7 – high reliability.‣ null – undetermined.Spacemin, Spacemax: The minimum and maximum station spacing expressed in metres.Start Date/End Date:State:Stations:Survey Name:Survey ID:Terr Corr Error:Terr Corr Meth:The start and end dates of data acquisition.The state(s) or territory (ies) covered by the survey.The number of gravity stations in the survey.The name of the survey.Each survey held in the Australian National Gravity Database iscatalogued by a Geoscience Australia survey number. This is theprimary reference.The error, expressed in units of micrometres per second squared in theterrain correction value.The method used to compute the Terrain Correction.‣ COM – Combination of two or more methods.‣ CUR – Method developed by Featherstone at CurtinUniversity.‣ DFA – Terrain Correction calculated using IntrepidGeophysics software.‣ EFD – Automatic estimation using a fine Digital terrainModel.‣ EST – Automatic estimation using a coarse Digital terrainModel.‣ GES – Terrain Correction calculated using Geosoft software.‣ HAM – Hand calculated using a hammer chart and detailedtopography.‣ LTC – Terrain Correction calculated using LASERTCprogram from Geophysical Software.‣ RIG – Rigorous method using in-situ observations.‣ RTC – Terrain Correction calculated using RASTERTCprogram from Geophysical Software.‣ SET – Statistically estimated terrain correction from domain27 January 2006 © Copyright Geoscience Australia 2006 xi