METHOD AND APPARATUS FOR VERTICAL VOLTAGE POTENTIAL MAPPING

摘要

A method of mapping voltage potential along a metal structural member extending underground through a range of depths comprises the steps of providing a voltage meter having positive and negative terminals, a referenc e electrode connected to the positive terminal, and a half-cell connected to t he negative terminal; forming at least one hole in the ground alongside the structural member; contacting the reference electrode with the structural member at an aboveground location; and positioning the half-cell at a series of test points in the hole(s) and taking a series of voltage potential measurements respectively corresponding to the series of test points, wherei n the test points are located at different depths. Preferably, the method further comprises the step of plotting test point depth versus voltage potential. A novel drill bit for drilling the hole through earth comprises a common wood-boring auger shank and a flat masonry-style drill bit tip.