The eastern part of the Volhynian Plateau extends, at first, as a narrow plateau zone between the valleys of the Boh and the Teterev on one side and of the Sluch on the other. Then the plateau spreads out like a fan toward the north. At the source of the Boh and the Sluch, the plateau reaches a height of 370 m.; at the sources of the Teterev, 340 m. Here the surface is level, except that here and there low, gently-rounded hills arise. In the broad, northern part, the Volhynian Plateau becomes much lower and finally separates into individual plateau islands, as, for example, near Novhorod-Volinsky, Zitomir, Ovruch, which rise gently from the marshy lowlands. The valleys of the Volhynian rivers, broad, flat, with gentle slopes and marshy bottoms, differentiate the Volhynian landscape most strongly from the Podolian. The Volhynian landscape presents a view of flat, wooded hills, slowly flowing streams between flat banks, marshes and marshy meadows, sandy ground—all signs of the proximity of the Polissye. The Dnieper Plateau has the outlines of a longish, irregular polygon. On the northwest it is bounded by the rocky valley of the Teterev, on the southwest by the Boh River, on the south and southwest by the Pontian steppe-plain, on the northeast by the Dnieper River. [49] This great space, however, does not constitute a uniform plateau. The broad river valleys and broad depressions which traverse the plateau have parted it into several sections. Only the uniform sub-layer and the geologic character, as well as the uniform appearance of the landscape, determine the natural unity of the region. The sub-layer of the Dnieper Plateau is made up of the primitive granite-gneiss clod of the Ukrainian horst. The granite-gneiss formations were folded in the pre-cambrian period. The folds and quarries stretch principally from north to south, and appear very distinctly near Zitomir and Korsun, and at the rapids of the Dnieper. The mesozoic layers also, which lie close to the granite-horst, are folded at Trekhtimiriv. The tertiary layers, which form a thin cover over the granite, lie mostly in undisturbed horizontal lines. Only along the right, steep bank of the Dnieper we see them folded and broken thru by quarries. In the neighborhood of the Shevchenko barrow they appear most distinctly. The occurrence of eruptive rock in the south of the plateau, appearing in mound-shaped flat hills, is, however, connected only with the old disturbances in the horst. This species of rock of the Dnieper Plateau appears almost solely in the declivities of the valleys and balkas. Otherwise it is covered everywhere by an immense mantle of loam, loess, and chornozyom. The glacial deposits, whose southern boundary passes through Zhitomir, Tarashcha, Chihirin, and Kreminchuk, present, in the territory of the Dnieper Plateau, examples of genuine fluvio-glacial moraine, as well as sands of no great depth, and in rather erratic distribution.