GSQ Thomson Extension 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 Extension TMI grid geodetic has a cell size of 0.00083 degrees (approximately 88m). 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 46530 line-kilometres of data at 400m line spacing and 80m terrain clearance.

总磁强度（Total magnetic intensity, TMI）数据用于测量地壳中造岩矿物含量差异引起的地球磁场强度变化。磁异常根据岩石的磁化率可分为正异常（磁场强度高于正常值）或负异常（磁场强度低于正常值）。数据通过标准方法处理，确保记录的响应仅来源于地下岩石。处理结果生成的数据集可用于解译地下地质结构。处理后的数据经GA地球物理学家质量检查，以确保GA发布的最终数据符合预期用途。
该GSQ Thomson Extension TMI大地测量网格的单元格大小为0.00083度（约88米），单位为纳特斯拉（nT）。生成此网格的数据由昆士兰州政府于2011年采集，包含46530线公里的数据，线间距400米，地形净空高度80米。