Blog | Advanced Geosciences Inc

Early Methods Of Groundwater Exploration

To best understand how electrical resistivity surveys for groundwater exploration work today, it’s important to understand where resistivity testing began. 

Brothers Conrad and Marcel Schlumberger performed the very first investigation of how electrical current moves through the ground and what you can detect using an electrical resistivity survey in the early 1900s. From their research came what is now one of the most common methods of groundwater exploration, vertical electrical sounding (VES).

VES uses four electrodes...

The Institute of Electrical and Electronics Engineers (IEEE) Standard 81-2012 “Guide for Measuring Earth Resistivity, Ground Impedance, and Earth Surface Potentials of a Grounding System”, suggests the fall-of-potential grounding test to be used to evaluate the capacity of an electrical grounding system—it is often used by subcontractors to power engineers. 

Why is the IEEE Standard 81 fall-of-potential grounding test important?

Grounding tests are mainly used at lightning protection systems, electrical substations, and industrial sites where expensive machinery needs to be...

One way that sinkholes form is when water in the atmosphere reacts with carbon dioxide and forms a weak carbonic acid. As the slightly acidic rainwater moves through fissures in the limestone, it begins to dissolve and widens the fissures—which eventually creates air or water filled pockets. When those pockets become expansive, they’re called “caves” or “voids.” This is a common natural phenomenon in limestone or dolomite known as karstification—but it can be dangerous, expensive, and life-threatening when the ceiling of a void weakens and caves in. This is known as a “sinkhole.” 

...