- The position of an intermediate horizontal layer in the lower half-space can be given inaccurately without any change in the thickness of the effective layer either by a slight layer shift upwards or downwards. Even though the layer shifts might be minimal, it could significantly alter the density variations of the disturbing masses in the effective layer. Here we investigate and demonstrate the effect of the variations in the position of the horizontal layer to the determined density variations. Subsequently due to the direct relationship between disturbing masses and the positions of the contact surfaces in an intermediate horizontal layer, the later are also determined. We finally demonstrate the efficacy by applying to actual geophysical data i.e. gravity data, for a micro-gravimetry site and/or localized structures in the Central Ranges of the Chubu District in Japan.