FEASIBILITY OF NATURAL SOURCE INDUCED POLARIZATION
天然场源激电法的可行性

The existing observation schemes for natural source induced polarization (NSIP) and the numerical modeling results of 2-dimension geoelectrical sections with horizontal and vertical electrical non-uniformity are analyzed. It is pointed out that the MT anomalies caused by conductive and electromagnetic effects are overwhelming superiority to the IP anomalies produced by the induced polarization effects. Accordingly, it is very difficulty to pick up the week IP anomalies from the strong EM anomalies. The existing observation schemes for NSIP are not of universal feasibility. The practical application prospects of NSIP are not optimistic. The control source IP with long offset is intrinsically same as NSIP. They are both taking IP obsevation in the "far zone of electromagnetic field". So it's practical application prospects are not optimistic too.