Solution Exercise 5

Calculate the apparent resistivity in the following arbitrary electrode configuration when a 5 mA current is injected between electrodes A and B, and 80 mV is measured between M and N.

[latex]\displaystyle K_{g}=\frac{2\pi }{\frac{1}{\overline{AM}}-\frac{1}{\overline{AN}}-\frac{1}{\overline{BM}}+\frac{1}{\overline{BN}}}[/latex]

[latex]\displaystyle =\frac{2\pi }{\frac{1}{2\mathrm{m}}-\frac{1}{3\mathrm{m}}-\frac{1}{4\mathrm{m}}+\frac{1}{3\mathrm{m}}}[/latex]

[latex]\displaystyle =25.1\mathrm{m}[/latex]

ρa = KgV/I)
= 25.1 m * 80 mV / 5 mA
= 400 ohm-m

Return to Exercise 5


Electrical Imaging for Hydrogeology Copyright © 2022 by Kamini Singha, Timothy C. Johnson, Frederick D. Day Lewis and Lee D. Slater. All Rights Reserved.