# Dictionary:Dar Zarrouk

(dar zar ruk') The name given by Maillet to resistivity parameters or curves that deal with layered anisotropic materials. The **dar Zarrouk variable** is the **transversal unit resistance** (), the depth integral of the transverse resistivity perpendicular to the strata; the **dar Zarrouk function** is the longitudinal unit conductance (), the depth integral of the conductivity parallel to the strata; and the **dar Zarrouk curve** is a plot of the mean resistivity () of the formation down to the depth *z*, plotted versus the anisotropy coefficient times :

where are layer thicknesses.^{[1]}

## References

- ↑ Maillet, R., 1947, The fundamental equations of electrical prospecting: Geophysics, 12, 529–556.