A Fabricated Resistivity Apparatus to Explore Buried Structures on the Bench and in the Field

Abstract

In the following study, an electrical resistivity apparatus was created and implemented in the laboratory as well as tested in the field, to accurately identify the location of a buried building foundation. The primary goal of the study was to test the accuracy of the apparatus which costs a fraction of the price of available electrical resistivity instrument. The apparatus consists of four electrodes set in a linear spread. An electrical current, produced by a standard 12-volt battery, is injected into earth material through the outer electrodes and the potential voltage is measured across the inner electrodes using a multimeter. The recorded potential and current values can then be used to calculate apparent resistivity of any given material. The study implemented Wenner array which consists of four electrodes placed equally distant from each other and also allows for higher accuracy and greater resolution when investigating lateral variations of resistivity in near-surface formations. The device successfully produced consistent results on the bench level revealing the location of small bricks buried under soil material. In the field, multiple transects were conducted in the summer of 2010 on Susquehanna University Campus where the foundation of Gustavus Adolphus Hall is located. The apparatus consistently provided accurate results when compared to a commercially produced electrical resistivity device, Iris SYSCAL R1+, and successfully revealed the location of the foundation.