The Effection of Electromagnetic Exploration by Sampling Delay

Abstract

Because of the effcetion of primary field. if select the sampling delay blindly, it will cause distortion of explanation of transient electromagnetic exploration. We analysis of the scope of influence of primary field at first, then study on the effect of different delays for detection:the small delay causes the early false anomaly. The full time apparent resistivity is less than the theoretical apparent resistivity. The depth of investigation gets small. On the contrary, the long time delay causes the loss of the superficial ground information. The full time apparent resistivity is more than the theoretical apparent resistivity. So it can reduce the false anomaly caused by the primary field decreases only when the acquisition of the inflection point delay is adopted. Then the computing apparent resistivity is close to the theoretical value and the apparent depth of investigation increases.