An exact solution is given for the electromagnetic induction in a dipping dike of finite conductivity, represented as a thin half-sheet in a nonconducting surrounding. The problem is formulated for arbitrary dipole or circular loop T x - R x configurations. The formal solution obtained by the Wiener-Hopf technique is cast into a rapidly convergent triple integral suitable for an effective numerical treatment. A good agreement is found between numerical results and analog measurements available for harmonic excitation. The transient response is obtained as a superposition of the half-sheet free-decay modes and is illustrated by some numerical examples for coincident loops, including a diagram for the approximate determination of conductance and depth of a vertical dike.--Journal abstract.