Between the lower and upper Carboniferous this whole area of paleozoic rocks was folded into a mountain system of Alpine height, ex tending from Belgium to the Sudeten (€Va riscian Mountains' of Suess, or Paleozoic Alps). Eruptions of volcanic matter accom panied the mountain making forming the gran ite massifs of the Erzgebirge, Black Forest. etc. In the valleys between the ranges and in the low country at their base the deposition of the carboniferous formation took place. The German Carboniferous belongs to the terres trial facies of the period, the lower part (Culm) being shales and sandstones of litoral origin with occasional coal seams (H.ainichen, Saxony) ; the upper includes the productive coal fields. They extend with little interrup tion from Belgium along the northern slope of the Rhenish Devonian into Westphalia (Ruhr Basin), and with the fields around Saarbriicken farther south, in Saxony (Zwickau), and Silesia (Waldenburg, Myslowitz), are the most import ant sources of coal supply in central Europe.
The Pertnain consists of two epochs: Rot liegendes and Zechstein. During the Rotlie gende the area remained land, the Paleozoic Alps were worn down to Mittelgebirge heights, and their deposits filled the depression with sands and conglomerates of a reddish color; hence the name. Occasionally coal beds occur between them. Volcanic activity m contued in some places (porphyrites and pitchstones of Saxony). In the Zechsteinthe ocean advanced again, leaving its epos on the northern edge of the Mittelgebirge, especially around the Harz and in northern Thuringia. Among them are the famous copper-bearing shales of Mansfeld, the Zechstein proper (shal low water limestone), and the immense salt beds of the upper Zechstein epoch (Stassfurt. Sperenberg) with their large supplies of gypsum and €arautO salts.
The Triassic period consisted of three epochs in Germany. In the first a shallow sea covered especially western Germany, forming the reddish sandstones (Buntsandstein) which cover miles and miles from Basel to Osna briklc, the western slope of the Eifel, the re gion around Tarnowitz in Silesia, and form the cliffs of Heligoland. This sea deepened in the second epoch producing a shell limestone (Mu schelkalk), but in the third (Keuper,_ pron coiper) was cut off from the main ocean and formed gay colored marls and sandstones with occasional coal seams. (Lettenkohle). The uppermost stage of the Keuper, the Rhaetic, shows the beginning of another transgression of the ocean, that of the Jurassic period.
About the Alpine facies of the Triassic, see ALPS.
The Jurassic ocean overflooded all of cen tral Europe, with only the tops of the moun tains standing out as isles. It reached a great
deal higher up on their sides than its present distribution would indicate, since the highest deposits were probably eroded in subsequent periods. At present we find its deposits in South Germany on both slopes of the Black Forest and Vosges, and especially in the range of the Swabian-Franconian Jura, where the lithographic stones of Solnhofen belong to its upper epoch. It also occurs in the north foot hills of the Mittelgebirge, near the Elbe in Saxony, in Silesia, and evidently underlies the whole lowland, cropping out frequently from under the younger • deposits.
Likewise a zone of Cretaceous hills skirts the northern border of the Jurassic ranges, with many isolated occurrences in the lowland. The second part of the Cretaceous again witnessed a large advance of the ocean, its deposits often lying on rocks several periods older in places which had never been submerged since; on ar chaic and paleozoic rocks in Saxony, on Carbon iferious in Westphalia, etc. The white chalk cliffs of Riigen and the Planer sandstone of Saxon, Switzerland, are the best known ex amples of German Cretaceous.
The Tertiary was again a period of great geological disturbances: Mountain folding, vol canic eruptions and changes of shore-lines. During the Eocene, almost all Germany was land; but in the Oligocene a shallow sea ex tended over the lowland as far as Bonn, Leip zig and Silesia. Local oscillations favored the formation of coal beds, to which soft coal measures (Halle and Leipzig) owe their origin. From the south the sea entered the rift valley formed by the breaking in two of the Black Forest-Vosges massif, the present Upper Rhine Valley. Toward the end of the Miocene, the folding of the Alps began and gradually shut off this bay from the ocean; it became brackish and finally a freshwater lake drained by the later Rhine (Mainzer Becken). All through the Mittelgebirge region volcanic eruptions ac companied these tectonic processes; the vol canoes and volcanic rocks of the Eifel, Sieben gebirge, Westerwald, Vogelsgebirge, Meissner, Rhon, northern Bohemia and the eastern Su deten, together with the hot springs which have created a belt of famous watering places along this line (Ems, Schwalbach, Wiesbaden, Nauheim, Kissingen, Franzensbad, Karlsbad, Marienbad, etc.), in the south the Kaiserstuhl, the Hegan volcanoes (Hohentwiel) and those of the Suabian Jura date from this period. During the Pliocene practically the whole of Germany was land again and ready for the in vasion of the Pleistocene ice sheet.