It is just case story. 
                  I had got a report with IP results for interpretation. 
This results in that the interpretation of such data is impossible.
This case shows how important it is to analyze field data before interpretation.
                  
                  
                | One line with IP anomaly from Report. The pictures quality was very poor. | |
| Same line in x2ipi (reference point is MN center) | |
| Left lower corner is blanked since values of apparent resistivity are less than zero. The measured voltage there is less than 1 mV. | |
| Let's look at IP decay curves. They are the same for some readings. | |
| Identical values in the field data is a result of Copy-paste. All results with a negative IP have been replaced by measurements from another part of line. The data table confirms this conclusion. It is just cheating. | 
This case shows how important it is to analyze field data before interpretation.
 
       
       
       
       
      
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