Ballarat, Vic, 1986 (GSV0312) (P1516), 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 Ballarat, Vic, 1986 (GSV0312) survey were acquired in 1986 by the VIC Government, and consisted of 11552 line-kilometres of data at 200m line spacing and 70m 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）数据用于量化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（磁场强度高于正常背景场）与负异常（磁场强度低于正常背景场），其类型取决于岩石的磁化率。本数据集经标准流程处理，确保记录的响应仅源自地下岩石。经处理得到的数据集可通过解译揭示地下地质构造。处理后的数据已由GA地球物理学家开展质量核查，确保GA发布的最终数据符合使用要求。本次测线数据集取自1986年澳大利亚维多利亚州巴拉瑞特（Ballarat, Vic）地区的（GSV0312）调查项目，该数据由维多利亚州政府于1986年采集，总测线长度达11552线公里，测线间距为200米，飞行离地高度为70米。为约束数据中的长波长分量，研究采用独立数据集——全澳航空地球物理调查（Airborne Geophysical Survey, AWAGS）的航空磁测数据，对本次调查数据的基准面进行控制。本调查数据已基本平差至AWAGS基准。