Carnarvon Basin North, WA, 2011 (P1234), 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 Carnarvon Basin North, WA, 2011 survey were acquired in 2011 by the WA Government, and consisted of 107266 line-kilometres of data at 400m line spacing and 60m 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。该数据集通过标准流程进行预处理，以确保记录的响应仅源于地下岩石。经处理后得到的数据集可用于解译，以揭示地下地质构造。经处理的数据会由GA的地球物理学家开展质量校验，确保GA发布的最终数据符合使用要求。本次发布的测线数据集源自2011年西澳大利亚州政府开展的北卡那封盆地（Carnarvon Basin North）航空磁测项目，共包含107266测线公里的数据，测线间距为400米，飞行离地高度为60米。为约束数据中的长波长成分，项目采用独立数据集——全澳航空地球物理调查（Australia-wide Airborne Geophysical Survey, AWAGS）航空磁测数据——对本次测线数据的基准面进行校正。本项目测线数据实质上已基于AWAGS数据完成平差处理。