Electrical Resistivity Imaging Equipment

Electrical Resistivity Imaging (ERI) is a subset of a broader method called Electrical Imaging (EI). Two components of Electrical Imaging are ERI (Electrical Resistivity Imaging) and IP Imaging (Induced Polarization).

Modern ERI equipement is used to automate the process of moving the 4 electrodes (2 transmitter electrodes and 2 receiver electrodes) around the surface which is very time consuming and labor intensive (expensive).

The Parts of a Electrical Imaging System for performing resistivity, induced polarization and SP measurements:

• a resistivity/IP/SP meter contains
  • a direct current (DC) transmitter
  • a sensitive volt measuring circuit (channel)
• Inversion modeling software (EarthImager) to compute the resistivity values in 1D, 2D or 3D.
• a switching apparatus (the AGI SwitchBox) capable of switching the transmitter and receiver connections quickly and efficiently
• an electrode cable with a number of electrode takeouts at a regular spacing (typically 6.25m or 20')
• stainless steel stakes: are used to connect the electrode cable to the ground via stainless steel springs. Stainless steel is used for corrosion resistance.
• a power source: AC/DC power supply with a gas generator or 12V deep cycle batteries