The glacial age had no particular significance for the surface configuration of the Dnieper Plain and the adjacent plateau spurs. Only in the north Chernihov country we find real traces of the glacier. The large peninsulas which the southern limit of the glacial boulders forms along the course of the Dnieper and the Don are by no means to be regarded as traces of two great glacial tongues. The sand and loam masses, with enclosed glacial boulders, which are found in the region of these peninsulas, are of fluvio-glacial origin, and were deposited by melted ice from the glacier on its way to the Black Sea. The northern limit of the black soil region is not in the least affected by these problematic glacial peninsulas.
After the glacial period, however, movements of the earth took place in the entire Ukrainian plateau group. It rose considerably, and the erosive action of the rivers began. At the point where the axis of the Ukrainian horst cuts the Dnieper, we find this rise of ground also in the Dnieper Plateau. The rapids of the Dnieper were formed at that time, and, up to the present, the giant river has not succeeded in leveling its falls.
That tectonic disturbances are not unknown to the
Dnieper Plain we learn from the occurrence of volcanic rock and displacement of the strata near Isachki, not far from the city of Lokhvitza, and on Mount Pivikha, north of Kreminchuk. It seems that along the northeast border of the Ukrainian horst a greatly disturbed area is hidden beneath more recent flat-piled rock layers. Great disturbances of the magnetic force of the earth seem to indicate the same.
The Dnieper Plain forms the last member in the northern plain district of the Ukraine. The southern plain district which extends along the northern banks of the Black Sea, from the delta of the Danube into the Kuban region, has since ancient times borne the accepted name of the Pontian Steppe-plain. Its old Ukrainian name is simply nis (lowland) or dike pole (wild field. The steppe-land and the river district, to this day, bear the famous name of Zaporoze (land below the rapids).
The Pontian steppe-plain is bounded on the north by the spurs of the Bessarabian, Podolian, Dnieper and Donetz Plateaus. On the south, by the sea-shore and the country at the foot of the Yaila Mountains, in Crimea. Past the Danube deltas the steppe-plain merges into the exactly similar steppe-plain on the Kuban.
The surface of the steppe-plain is exceptionally flat, slightly undulating only at the northern border, where the transition to the southern spurs of the Ukrainian plateau group proceeds imperceptibly. Innumerable barrows (mohyla) are as characteristic of the landscape of the Pontian Steppe-plain as the flat plate-shaped depressions of the ground, with small temporary lakes, the swampy flat valleys and the small salt marshes with their peculiar vegetation.
The many balkas, which divide the steppe-plain into innumerable low plateaus, do not affect the grand uniformity of the steppe landscape very much. As in the neighboring plateaus, they are cut in deep, but do not become visible to the traveler until he comes directly upon them. The pliocene steppe-lime which predominates in the entire steppe-plain, covers the sarmatian and Mediterranean strata, and reveals the crystalline substratum only in the west of the Dnieper in the neighborhood of the Dnieper Plateau, and forms rocky cornices on the slopes of the balkas. Lesser tectonic disturbances, in the shape of anticlinals and synclinals, have affected these youngest tertiary formations also. They are covered by a mantle of loess and black earth, which becomes constantly thinner toward the south. The typical chornozyom gives way, south of the parallel of Kherson, to the brown, also very fertile steppesoil, which is accompanied in long stretches, however, by the saline earth. To the east of the Dnieper, at the southern spurs of the Donetz Plateau, the crystalline substratum also appears to a great extent, in banks of rock, in the midst of the steppe-plain.
Only along the large streams of the steppe country does the nature of the land change. Their valleys are broad and swampy, covered by the so-called plavni. Interminable thickets of sedge and seeds, marsh forest and meadows, together with innumerable river branches, old river beds, and small lakes, make up a beautiful, fresh, verdant country in the midst of the boundless steppe, whose vernal dress, resplendent with blossoms, turns yellow and blackish-brown in summer and fall, from the fierce glow of the sun.
Streams and Rivers of the Ukraine