文中通过二维及相应的三维理论模型响应在不同方向上反演结果的对比分析,探讨了大地电磁一、二维反演中数据旋转方向的选择问题。发现在纯二维情况下,宜采用主轴方向的数据进行反演。此时如采用旋转到测线方向的数据,则要求测线与构造倾向之间的夹角不能太大(对于本文的模型不能大于30°)。而在三维情况下,采用旋转到最佳主轴方向的数据进行二维反演未必能得到比旋转到测线方向更优的反演结果。由于实测资料一般都可视为三维响应,故本文认为在实际资料处理中,对于那些构造走向明显,而测线是尽量垂直于构造的情况下,可直接将数据旋转到测线方向后进行二维反演,从而避免最佳主轴方向上极化模式选取的困难。
The paper discussed the issue how to select the data rotation direction in 1-D and 2-D MT inversion by correlating and analyzing the inverted results of 2-D and relevant 3-D theoretical model responses,which discovered that it is appropriate to use the main axial data for inversion in true 2-D situation.In this case,if using the data rotated into line direction,it demands that the angle between line and structural dip can't be too large (can't be greater than 30° in the model presented in the paper,for exam...