P1258 Browse Basin 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 P1258 Browse Basin TMI Grid Geodetic has a cell size of 0.00167 degrees (approximately 182m). The units are in nanoTesla (or nT). The data used to produce this grid was acquired in 2013 by the WA Government, and consisted of 190247 line-kilometres of data at 800m line spacing and 80m terrain clearance.

总磁强度（Total Magnetic Intensity, TMI）数据测量由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（磁场强于正常值）或负异常（磁场弱于正常值）。数据通过标准方法处理，以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通过解释揭示地下地质结构。GA地球物理学家会对处理后的数据进行质量检查，确保GA发布的最终数据符合预期用途。

这个P1258 Browse盆地TMI大地测量网格的单元格大小为0.00167度（约182米）。单位为纳特斯拉（nT）。生成该网格所用的数据由西澳大利亚州政府（WA Government）于2013年采集，包含190247线公里的数据，线间距为800米，地形净空高度为80米。