Rawlinson magnetic 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 Rawlinson magnetic 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 1998 by the WA Government, and consisted of 48394 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成分差异引发的地球磁场强度变化。磁异常根据岩石磁化率分为正异常（磁场强于正常值）与负异常（磁场弱于正常值）。数据经标准方法处理，确保记录响应仅来源于地下岩石；处理结果生成的数据集可通过解释揭示地下地质结构。经处理的数据由GA地球物理学家开展质量检查，以保障GA发布的最终数据符合用途要求。该Rawlinson大地磁网格的单元格大小为0.00083度（约88米），单位为纳特斯拉（nanoTesla, nT）。生成此网格的原始数据由西澳大利亚政府于1998年采集，包含48394线路公里数据，线路间距400米、地形净空高度80米。