ABSTRACT: The dip and slope were functionally studied in respect of tangent (Fig. 1) and the results were applied on the graphic of tangent (Fig. 2). It is only after this, it is noticed that these curved contacts were possible in some limited areas, as it seems In Fig. 2 (S1( S s and S4)ı according to tangent graphics.Also, the effects of bed dips and morphological slopes to the position and condition of Hthologİeal contacts formed at toplines and valleys, studied. As it is known, up to now five positions of lithological contacts have been found out and described (Billings, M. P., 1972, Structural geology). When it is found out by writer that these two basic conditions and each condition included three positions, the sixth position is added to the contact types. The straight or curved contact lines occour the same way on the toplines as in the walleys, only direction of the curvature reverse. Each position of the contact lines has been mathematically described by a function. Thus finally some functions that are very practical m use, have been systematically explained and offered.