Marree, SA, 2012 (P1255), 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 Marree-Warrina Airborne Magnetic & Radiometric Survey, SA, 2012 survey were acquired in 2012 by the SA Government, and consisted of 132484 line-kilometres of data at 400m line spacing and 80m 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内造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（磁场强度高于正常值）与负异常（磁场强度低于正常值），具体取决于岩石的磁化率。该数据通过标准处理流程进行处理，以确保记录的磁场响应仅由地下岩石引起。处理后得到的数据集可通过解译揭示地下地质结构。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发布的最终数据满足使用需求。该测线数据集源自2012年开展的马里-沃里纳航空磁测与放射性测量（Marree-Warrina Airborne Magnetic & Radiometric Survey）项目（南澳大利亚州，SA），由南澳州政府于2012年采集完成，总测线长度达132484线公里，测线间距为400米，飞行离地高度为80米。为约束数据中的长波长分量，项目采用独立数据集——全澳航空地球物理测量（Australia-wide Airborne Geophysical Survey, AWAGS）航空磁测数据——对本次测区数据的基准值进行校正。本次测量数据已基本调平至AWAGS基准。