Dixon Range - Gordon Downs, WA, 1991 (P584), magnetic line data, AWAGS levelled

Total magnetic intensity (TMI) data measures variations in the intensity of the Earth's magnetic field caused by the contrasting content of rock-forming minerals in the Earth crust. Magnetic anomalies can be either positive (field stronger than normal) or negative (field weaker) depending on the susceptibility of the rock. The data are processed via standard methods to ensure the response recorded is that due only to the rocks in the ground. The results produce datasets that can be interpreted to reveal the geological structure of the sub-surface. The processed data is checked for quality by GA geophysicists to ensure that the final data released by GA are fit-for-purpose. These line dataset from the Dixon Range - Gordon Downs, WA, 1991 survey were acquired in 1992 by the WA Government, and consisted of 43000 line-kilometres of data at 400m line spacing and 100m terrain clearance. To constrain long wavelengths in the data, an independent data set, the Australia-wide Airborne Geophysical Survey (AWAGS) airborne magnetic data, was used to control the base levels of the survey data. This survey data is essentially levelled to AWAGS.

总磁强度（Total Magnetic Intensity, TMI）数据用于测量由地壳中成岩矿物成分差异引发的地球磁场强度变化。磁异常可分为正异常（磁场强度高于正常背景场）与负异常（磁场强度低于正常背景场），具体取决于岩石的磁化率。该数据集通过标准流程处理，以确保记录的磁场响应仅源于地下岩石。经处理得到的数据集可通过地质解译揭示地下地质构造。经处理的数据由GA地球物理学家开展质量核查，以确保GA发布的最终数据满足使用要求。本次采用的测线数据集源自1991年在西澳大利亚州（WA）开展的迪克森岭-戈登当斯勘测项目，由西澳大利亚州政府于1992年采集完成，总测线长度达43000线公里，测线间距为400米，飞行地形离地高度为100米。为约束数据中的长波长分量，项目引入独立数据集：全澳航空地球物理调查（Airborne Geophysical Survey, AWAGS）航空磁测数据，用于校正本次勘测数据的基准电平。本次勘测数据已基本以AWAGS为基准完成调平。