Patent ID: 9664812
Date: 2017-05-30
CPC Classifications: E21B,G01V

Claim:
1. A method of detecting standoff in a borehole, comprising: injecting an electric current from buttons disposed along a line on an equipotential pad into a subterranean formation surrounding the borehole, each of the buttons being similar to a same size as one another, and the buttons including at least two outer buttons and one or more inner buttons, the one or more inner buttons disposed along the line in between the at least two outer buttons; monitoring a voltage difference between the buttons and a return electrode; determining an apparent resistivity between the buttons and the return electrode; determining a first current for the at least two outer buttons and a second current for the one or more inner buttons; determining a ratio of the first current to the second current; and determining a standoff condition between the pad and the borehole based on the determined ratio.