Patent ID: 9405034
Filing Date: 2016-08-02
CPC Classification: G01V

Claim Text:
1. A method for estimating a property of an earth formation in a zone of investigation, the earth formation comprising the zone of investigation and another zone, the method comprising: applying a compound pulse of electromagnetic energy to the earth formation using a transmitter disposed in a borehole penetrating the earth formation, the compound pulse comprising a shape to induce a predominately greater amount of current in the zone of investigation than in the another zone, wherein the compound pulse comprises a first pulse and a second pulse, the first pulse comprising an amplitude whose absolute value is different from an absolute value of the amplitude of the second pulse, a duration of the first pulse being greater than a duration of the second pulse when a polarity of the first pulse is different from a polarity of the second pulse, and the first pulse is applied before the second pulse and the amplitude of the first pulse is greater than the amplitude of the second pulse; receiving a response of electromagnetic energy from the current induced by the compound pulse; and estimating the property from the response of electromagnetic energy.