GSWA Eucla Basin 2 Loongana 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 GSWA Eucla Basin 2 Loongana TMI Grid Geodetic has a cell size of 0.00042 degrees (approximately 43m). The units are in nanoTesla (or nT). The data used to produce this grid was acquired in 2010 by the WA Government, and consisted of 114979 line-kilometres of data at 200m line spacing and 50m terrain clearance.

总磁强度（Total Magnetic Intensity, TMI）数据用于测量地壳中成岩矿物成分差异引发的地球磁场强度变化。磁异常可分为正异常（磁场强度高于正常值）与负异常（磁场强度低于正常值），具体取决于岩石的磁化率。该数据通过标准流程处理，以确保所记录的响应仅源自地下岩石。处理后生成的数据集可通过解译揭示地下地质构造。经处理的数据已由GA地球物理学家开展质量核查，以确保GA发布的最终数据符合使用要求。本GSWA尤克拉盆地2号卢纳纳总磁强度格网大地测量数据集的单元格尺寸为0.00042度（约43米），数据单位为纳特斯拉（nanoTesla, nT）。本格网所用数据由西澳大利亚州政府于2010年采集，涵盖总长度达114979千米的测线数据，测线间距为200米，地形离地高度为50米。