MRTAS Offshore NE Tasmania 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 MRTAS Offshore NE Tasmania magnetic grid geodetic has a cell size of 0.00167 degrees (approximately 163m). The units are in nanoTesla (or nT). The data used to produce this grid was acquired in 2008 by the TAS Government, and consisted of 29287 line-kilometres of data at 800m line spacing and 95m terrain clearance.

总磁场强度（Total magnetic intensity, TMI）数据可用于表征由地壳内造岩矿物组分差异所引发的地磁场强度变化。磁异常可分为正异常（磁场强度高于基准值）与负异常（磁场强度低于基准值）两类，其极性与强度取决于岩石的磁化率。本数据集通过标准作业流程完成处理，确保记录的地球物理响应仅源自地下岩体。经处理后生成的数据集可通过解译，揭示地下区域的地质构造特征。GA地球物理学家已对处理后的数据开展质量核查，确保GA发布的最终数据符合实际使用需求。本塔斯马尼亚东北部近海MRTAS大地测量磁网格数据集的格网单元尺寸为0.00167度（约合163米），数据单位为纳特斯拉（nanoTesla, nT）。用于生成该网格的航磁数据由塔斯马尼亚州（TAS）政府于2008年采集，总测线长度达29287测线公里，测线间距为800米，飞行离地高度为95米。