The Granites A, NT, 1988 (P620), 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 The Granites, NT, 1988 survey were acquired in 1988 by the NT Government, and consisted of 9778 line-kilometres of data at 500m line spacing and 90m 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.

总磁场强度（Total Magnetic Intensity, TMI）数据用于表征由地壳中成岩矿物组分差异引起的地球磁场强度变化。磁异常可根据岩石的磁化率分为正异常（磁场强度高于正常值）与负异常（磁场强度低于正常值）。该数据集采用标准流程进行预处理，以确保记录的响应仅源于地下岩石。经处理后得到的数据集可通过解译揭示地下地质构造。经处理的数据由GA的地球物理学家开展质量核查，以确保GA发布的最终数据符合使用要求。本次测线数据集源自北领地（Northern Territory, NT）格兰尼特斯（The Granites）1988年航空磁测项目，由北领地政府于1988年采集，总测线长度达9778线公里，测线间距为500米，飞行地形离地高度为90米。为压制数据中的长波长分量，研究人员采用独立数据集——全澳航空地球物理调查（Australia-wide Airborne Geophysical Survey, AWAGS）航空磁测数据——对本次测线数据的基准水平进行校正。本测线数据已基本匹配AWAGS基准。