Impedance between cable k and p in ground

Definition according to Cigré guide 531 chapter 4.2.1, parameter $z_ij$.

Symbol
$z_{kp}$
Unit
$\Omega$/m
Formulae
$\frac{\omega \mu_0 \mu_{earth}}{2\pi} \left(\ln\left(\frac{L_{earth}}{d_{kp}}\right)-\frac{2}{3} m_{earth} \left(L_{ck}+L_{cp}\right)\right)$