GSQ Anakie Qld magnetic vd1 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 GSQ Anakie Qld magnetic vd1 grid geodetic is a first vertical derivative of the Total Magnetic Intensity grid for the Anakie Qld, 1990.This grid has a cell size of 0.00096 degrees (approximately 102m). The grid has units of nanoTesla per km (or nT/km). The data used to produce the TMI grid was acquired in 1990 by the QLD Government, and consisted of 15068 line-kilometres of data at 400m line spacing and 60m terrain clearance. A Fast Fourier Transform (FFT) process was applied to the original grid to calculate the first vertical derivative grid.

总磁强度（Total Magnetic Intensity, TMI）数据用于测量由地壳中成岩矿物含量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。该数据集已通过标准流程进行处理，以确保所记录的响应仅源自地下岩石。处理后得到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。
本次的GSQ昆士兰州阿纳基（Anakie Qld）磁异常vd1网格大地测量数据，是1990年阿纳基地区总磁强度网格的一阶垂直导数数据。该网格的单元格大小为0.00096度（约合102米），单位为纳米特斯拉每千米（nT/km）。用于生成该总磁强度网格的数据由昆士兰州政府于1990年采集，涵盖15068线千米的观测数据，线距为400米，地形离地高度为60米。研究人员通过快速傅里叶变换（Fast Fourier Transform, FFT）流程对原始网格进行处理，以计算得到该一阶垂直导数网格。