The Ex and Hz amplitude are monotonic functions of the resistivity, and numerical algorithm can be utilized to obtain the high-precision apparent resistivity for all frequencies. On this basis, we focus on the comparative analysis of the resolution for Ex field, Hz field, and Cagniard apparent resistivity to conductive and resistance targets, which proves that the Ex field may have a better resolution for the resistance bodies, and the Hz field can better identify the conductive target. Besides, the electromagnetic data is often distorted by the static effect, which seriously affects the application effect of the electromagnetic method. The influence of the static effect on the Ex field, Hz field, is also analyzed. The apparent resistivity based on the Ex field and Cagniard apparent resistivity are severely affected by the static effect which can cover deep anomalous bodies, but the apparent resistivity based on the Hz field is almost unaffected by the static effect. At last, a more efficient observation way is provided for the resistance and conductive targets, respectively.
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