Hamersley Basin (Mt Phillips,Mt Egerton,Collier,Wyloo) A, WA, 1983 (P513), 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 Hamersley Basin (Mt Phillips,Mt Egerton,Collier,Wyloo), WA, 1983 survey were acquired in 1983 by the WA Government, and consisted of 44282 line-kilometres of data at 1500m line spacing and 100m 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）数据可用于测量由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。该数据集采用标准流程进行处理，以确保记录的响应仅源于地下岩石。经处理得到的数据集可通过解译揭示地下地质构造。经处理的数据由GA地球物理学家开展质量校验，以确保GA发布的最终数据满足使用需求。本次1983年勘查的测线数据集采集自西澳大利亚州（Western Australia, WA）哈默斯利盆地（菲利普斯山、埃杰顿山、科利尔、怀卢），由西澳大利亚州政府于1983年完成采集，总测线长度达44282千米，测线间距为1500米，航空离地高度为100米。为约束数据中的长波长分量，研究人员采用独立数据集——澳大利亚全域航空地球物理调查（Airborne Geophysical Survey, AWAGS）航空磁测数据——对本次勘查数据的基准水平进行校正。本次勘查数据已基本匹配AWAGS基准。