The total magnetization of an underground magnetic source is the vector sum of the induced magnetization and the natural remanent magnetization. The direction of the total magnetization serves as important a priori information in the inversion and processing of magnetic data. We demonstrated that the total gradient of the magnetic potential with vertical magnetization constitutes the envelope of the vertical component of the magnetic field for all directions of the Earth's field and source magnetization. The total gradient of the magnetic potential with vertical magnetization and the reduction‐to‐the‐pole field simultaneously tend to achieve maximum symmetry near the correct total magnetization direction. As a result, the total magnetization direction can be estimated by computing the correlations between the reduction‐to‐the‐pole and the total gradient of the magnetic potential with vertical magnetization. The proposed method yields accurate magnetization directions in synthetic model examples. The total gradient of the magnetic potential with vertical magnetization is less susceptible to data noise than transforms which are derived from the high‐order magnetic field derivatives or tensors. The estimation results are slightly affected by changes in the source magnetization direction. In a field example in the Weilasito region (North China), the reduction‐to‐the‐pole fields calculated using the estimated magnetization directions are well centred over the source. The proposed method obtained a more focused magnetization direction than that of a three‐dimensional magnetization vector inversion. The total gradient of the magnetic potential with vertical magnetization therefore provides a novel and accurate approach to determine the total magnetization direction from the total field anomaly in a variety of situations.

中文翻译：

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通过极点磁异常与垂直磁化磁势总梯度之间的相关性确定磁化方向

地下磁源的总磁化强度是感应磁化强度和自然剩磁的矢量和。总磁化强度的方向是磁数据反演和处理中重要的先验信息。我们证明，具有垂直磁化强度的磁势总梯度构成了地球磁场和源磁化强度所有方向的磁场垂直分量的包络线。垂直磁化和极场还原的磁势总梯度往往在正确的总磁化方向附近实现最大对称性。因此，可以通过计算极点还原和磁势与垂直磁化的总梯度之间的相关性来估计总磁化方向。所提出的方法在合成模型示例中产生准确的磁化方向。与从高阶磁场导数或张量导出的变换相比，垂直磁化的磁势总梯度不易受数据噪声的影响。估计结果受源磁化方向变化的影响较小。在维拉西托地区（华北）的一个场示例中，使用估计的磁化方向计算的极场还原很好地集中在源上。该方法比三维磁化矢量反演获得了更集中的磁化方向。因此，具有垂直磁化的磁势的总梯度提供了一种新颖且准确的方法，用于在各种情况下根据总场异常确定总磁化方向。