GSQ Thomson Orogen TMI grid geodetic

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.This GSQ Thomson Orogen TMI grid geodetic has a cell size of 0.00083 degrees (approximately 87m). The units are in nanoTesla (or nT). The data used to produce this grid was acquired in 2011 by the QLD Government, and consisted of 298198 line-kilometres of data at 400m line spacing and 80m terrain clearance.

总磁场强度（Total Magnetic Intensity, TMI）数据用于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（磁场强度高于正常背景值）与负异常（磁场强度低于正常背景值）两类，其类型取决于岩石的磁化率。该数据已通过标准处理流程完成预处理，以确保所记录的磁场响应仅源自地下岩石。经预处理得到的数据集可通过解译揭示地下地质结构。经处理的数据已由GA地球物理学家开展质量核查，以保障GA发布的最终数据符合使用要求。本次的GSQ汤姆逊造山带TMI大地测量网格数据集的网格单元尺寸为0.00083度（约87米）。数据单位为纳特斯拉（nanoTesla, nT）。用于生成该网格的数据由QLD政府于2011年采集，累计测线长度达298198公里，测线间距为400米，飞行离地高度为80米。