Glenormiston, QLD, Sesmic Refraction and Magnetic, 1977 (P447), 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 Glenormiston, QLD, Sesmic Refraction & Magnetic, 1977 survey were acquired in 1977 by the QLD Government, and consisted of 5369 line-kilometres of data at 1000m 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.

总磁场强度（Total Magnetic Intensity, TMI）数据用于测量由地壳内造岩矿物成分差异所引起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），其分类取决于岩石的磁化率。该数据通过标准处理流程进行加工，以确保所记录的响应仅源于地下岩石。经处理得到的数据集可用于解译地下地质结构。经处理的数据由GA地球物理学家开展质量核查，以确保GA发布的最终数据符合使用要求。本次测线数据集源自1977年昆士兰州格伦诺曼斯顿地震折射与磁法调查，由昆士兰州政府于1977年采集，共包含5369测线千米的数据，测线间距为1000米，地形离地高度为100米。为压制数据中的长波长成分，本次调查采用独立数据集——全国航空地球物理调查（Australia-wide Airborne Geophysical Survey, AWAGS）航空磁法数据——来校正本次调查数据的基准面，本调查数据实质上已基于AWAGS数据完成平差处理。