Bathurst NSW 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 Bathurst NSW magnetic grid geodetic has a cell size of 0.0005 degrees (approximately 51m). The units are in nanoTesla (or nT). The data used to produce this grid was acquired in 1991 by the NSW Government, and consisted of 68244 line-kilometres of data at 250m line spacing and 80m terrain clearance.

总磁强度（Total Magnetic Intensity, TMI）数据可量化表征地壳中成岩矿物组分差异所引发的地球磁场强度波动。根据岩石磁化率的不同，磁异常可分为正异常（磁场强度高于正常背景场）与负异常（磁场强度低于正常背景场）两类。该数据集通过标准化流程开展预处理，以确保所记录的磁场响应仅来源于地下岩石的影响。经处理得到的数据集可通过地质解译，揭示地下深部的地质构造特征。经处理后的数据集由GA地球物理学家开展质量核验，以保障GA发布的最终数据符合应用要求。本次发布的新南威尔士州（New South Wales, NSW）巴瑟斯特磁测网格大地数据集，其网格单元尺寸为0.0005度（约合51米），数据单位为纳特斯拉（nanoTesla, nT）。该网格的原始数据由新南威尔士州政府于1991年采集，总测线长度达68244线公里，测线间距为250米，飞行离地高度为80米。