Geometric coefficient for the normal sonde

Input(s)

AM: Midpoint Between Electrodes a and M (m)

Output(s)

$G_{N}$: Geometric Coefficient for the Normal Sonde (m)

Formula(s)

$$ G_{N}=4 * \pi * A M $$

Reference(s)

Bassiouni, Z., 1994, Theory, Measurement, and Interpretation of Well Logs. SPE Textbook Series Vol. 4. Chapter 5, Page: 95.