  We consider the inverse problem in geophysics of imaging the subsurface of
the Earth in cases where a region below the surface is known to be formed by
strata of different materials and the depths and thicknesses of the strata and
the (possibly anisotropic) conductivity of each of them need to be identified
simultaneously. This problem is treated as a special case of the inverse
problem of determining a family of nested inclusions in a medium
$\Omega\subset\mathbb{R}^n$, $n \geq 3$.
