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An erosional surface underlain by rocks that show more complex structural style than in the younger rocks above. In simple cases, the older strata are either folded or homoclinally inclined and the younger ones are only gently inclined or are subhorizontal. The photograph shows this latter type in the northwest highlands of Scotland close to the Irish sea. In some cases the younger strata just overlie the igneous plutonic rocks, this being a nonconformity. In cases where the strata above and below have the same attitude, the term disconformity is used. Obviously, in case of the last, there was no change in the attitude before the deposition of younger strata began, the only event being the uplift and erosion. Hence, both the sets show the same attitude as they were subjected to the diastrophic movements or tectonic forces together, after the formation of erosional surface.