SA Exploration Initiative - Area B1, SA, 1993 (P701), 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 SA Exploration Initiative - Area B, (B1- B4) SA, 1993 survey were acquired in 1993 by the SA Government, and consisted of 75571 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）数据用于测量地壳内造岩矿物成分差异所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）两类，具体取决于岩石的磁化率。该数据集通过标准流程处理，以确保所记录的响应仅来自地下岩石。经处理得到的数据集可通过解译揭示地下地质结构。经处理的数据需由GA地球物理学家开展质量核验，以确保GA发布的最终数据满足使用需求。本次测线数据集源自1993年南澳大利亚勘探倡议B区（B1-B4）的航磁调查工作，由南澳政府于1993年完成采集，总测线长度达75571测线公里，测线间距为400米，飞行离地高度为80米。为压制数据中的长波长背景信号，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——对本次航磁调查数据的基准水平进行统一校正。本次调查数据已基本基于AWAGS基准完成平差处理。