Hodgkinson-Georgetown Block B, QLD, 1999, Prospectivity Plus Init. (P798), 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 Hodgkinson-Georgetown Block B, QLD, 1999, Prospectivity Plus Init. survey were acquired in 1999 by the QLD Government, and consisted of 102900 line-kilometres of data at 200m 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）数据用于量化表征地壳中成岩矿物组分差异引发的地球磁场强度变化。磁异常可分为正异常（磁场强度高于背景水平）与负异常（磁场强度低于背景水平），其类型取决于岩石的磁化率。该数据集通过标准化流程开展处理，以确保记录的磁场响应仅源自地下岩石。处理所得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验，以确保GA发布的最终数据符合应用要求。本次测线数据集源自1999年昆士兰州（QLD）霍奇金森-乔治敦区块B的「远景增强计划（Prospectivity Plus Init.）」调查项目，由昆士兰州政府于1999年采集完成，总测线长度达102900测线千米，测线间距为200米，航测离地高度为80米。为压制数据中的长波长干扰成分，本次调查采用独立数据集——全澳航空地球物理调查（Australia-wide Airborne Geophysical Survey, AWAGS）航空磁测数据——作为基准，对调查数据的基值进行平差校正。本次调查数据实质上已匹配至AWAGS基准体系。