Tasmania merge 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 Tasmania merge tmi grid geodetic has a cell size of 0.00083 degrees (approximately 81m). The units are in nanoTesla (or nT). The data used to produce this grid was acquired in 2005 by the TAS Government, and consisted of None line-kilometres of data at a line spacing between 100m and 1500m, and 80m terrain clearance.

总磁强度（Total Magnetic Intensity, TMI）数据用于表征地壳中成岩矿物含量差异所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），其类型取决于岩石的磁化率。该数据通过标准处理流程开展处理，以确保记录的磁场响应仅由地下岩石产生。处理后得到的数据集可通过解译揭示地下地质构造。GA的地球物理学家会对处理后的数据进行质量核查，确保GA对外发布的最终数据满足使用需求。本次发布的塔斯马尼亚合并TMI大地测量网格数据集，网格单元尺寸为0.00083度（约81米），数据单位为纳特斯拉（nanoTesla, nT）。用于生成该网格的数据由塔斯马尼亚州政府（TAS Government）于2005年采集，测线间距介于100米至1500米之间，地形离地高度为80米，总测线长度为None千米。