Otway Basin 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 Otway Basin magnetic grid geodetic has a cell size of 0.001 degrees (approximately 99m). The units are in nanoTesla (or nT). The data used to produce this grid was acquired in 1994 by the SA, VIC Government, and consisted of 44345 line-kilometres of data at 500m line spacing and 130m 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（Magnetic Anomalies）可表现为正异常（磁场强于正常值）或负异常（磁场弱于正常值），具体取决于岩石的磁化率。数据通过标准方法处理，以确保记录的响应仅源于地下岩石。处理结果生成的数据集可通过解释揭示地下地质结构。处理后的数据由GA地球物理学家进行质量检查，以确保GA发布的最终数据符合预期用途。

该奥特韦盆地（Otway Basin）地磁格网的大地测量单元尺寸为0.001度（约99米）。单位为纳特斯拉（nanoTesla，简称nT）。生成该格网所用的数据由SA和VIC政府于1994年采集，包含44345线公里的数据，线间距为500米，地形净空高度为130米。