Germany Lithological Composition of the Soil

By | January 27, 2022

In Germany, lands of all ages are represented, starting with the archaic. The rocks of the mountains that form the edge of the Bohemian Basin, the Bavarian Forest, correspond to the latter; there is some in the Fichtelgebirge, in the Ore Mountains and in the Sudetes (Giant Mountains, Eulen). The nuclei of the Black Forest, the Hardt, the Odenwald, the Spessart, the Northern Thuringian Forest and the Kyffhäuser Mountains, probably a part of the phyllites of the Fichtelgebirge, eastern Thuringia and the Silesian mountains are of crystalline schists. The silky crystalline rocks and the green schists at the edge of the Taunus and Hunsrück perhaps represent the Eozoic Archaic (Algonchian by other authors). The paleozoic formations of Germany underlying the Carbonic, of which a ‘ quartz sandstone containing fragments of other more ancient rocks, constitute the ground that the old geologists said of the greywacke or transition. The deposits of litantrax are characteristic of the second part of the immense group of Paleozoic strata. The shale rocks have a large extension there. As for the position, the paleozoic rocks of central Europe are always in discord with the underlying algonchic and archaic ones, on whose denudation surface they rest. In turn, the Paleozoic sediments appear raised, folded and crossed by fractures that attest to the actions of the tectonic dynamism subsequent to their formation. Erciniano dai Francesi, Varisco dal Suess and on which we will have to return. The cambric strata have scarce extension in Gemiania: the argilloscists and quartzites of the Fichtelgebirge and Vogtland between Thuringia and Saxony are ascribed to them; and the highly complicated tectonic core of the Hohes Venn, on which the Devonico relies in discordance, is certainly Cambric. By the middle of this period, all of present-day Germany was probably covered by the sea, which retreated towards the end of that period.

Much more extensive are the torpedo terrain. In the western part they are found in the Schistose Mountains of the Rhine from Kellerwald in the direction of N. of Marburg up to Herborn, then to Lindner Mark near Giessen, in central Germany (Harz), in Thuringia, in Franconia, in the Fichtelgebirge, concordant with the Silurico which they are superimposed; in East Germany, Saxony and Lower Silesia; fossils prove that all of central Europe. to S. even beyond the limits assigned by us, it was covered by a deep sea where characteristic hydrozoans, the graptolites, lived.

In the devonic soil from a zone of shallow sea sediments and neritic faunas that from the Ardennes to the northern parts of the lower Rhine mountains and the upper Harz is directed towards the middle mountains of Poland, another zone can be distinguished southernmost sedimentary that crosses Germany from the S. part of the Schistose Mountains of the Rhine to the lower Harz, Thuringia and Bohemia and is deep sea. The series of the Schistosi of the Rhine, which form the most powerful mass of Paleozoic rocks in Gemiania, is particularly remarkable. These mountains consist of folds strongly compressed about SW. NE. The Harz is also very important for its series and the extension of the devonic lands in eastern Thuringia, in the Fichtelgebirge, is considerable. The lower Devonico is represented by clastic formations of shallow sea, built with materials probably removed from the northern continent of the Old-Red and the cambric soils of Rocroi and Hohes Venn. The lower Devonico is missing entirely in Thuringia and the Fichtelgebirge. The middle Devonico, calcareous, is found in the Eifel and in southern Westphalia, where it is represented by arenaceous rocks. The medium Devonico of the Dill and Lahn river basins (schists and quartzites, where diabases and tuffs also represent the Eifel and South Westphalia, where it is represented by sandstone rocks. The medium Devonico of the Dill and Lahn river basins (schists and quartzites, where diabases and tuffs also represent the Eifel and South Westphalia, where it is represented by sandstone rocks. The medium Devonico of the Dill and Lahn river basins (schists and quartzites, where diabases and tuffs also represent theeruptive facies). Upper Devonico is distinguished by many different facies (coral limestone, marly limestone, marl, low sea sandstone, schist and deep sea limestone, diabase and tuff) in the Eifel, Aachen, Sauerland.

Also in the Harz and in the Fichtelgebirge the Devonico plays an important part in the constitution of the soil. Of the devonic rocks, the quartzites of the Taunus, the powerful schists of the Hunsrück, the stringocephalus limestones and the climenie limestones are of particular importance in terms of morphology; in both there are interspersed diabasic effusions and important deposits of hematite. The deeper devonic strata lie in discord on those of the Cambric and the lower Siluric. Thus in Thuringia and in the Fichtelgebirge a large stratigraphic gap corresponding to the whole lower Devonico, shows that in that period that part of the region had emerged and that then there was a marine transgression for which the layers of the middle and upper Devonico were deposited. In Lower Silesia the transgression corresponds to the upper Devonic.

The Carbonic system, in addition to the geological and morphological interest, has a very large economic one, because it contains the deposits of litantrax. Let’s start with West Germany. Continuing eastward from the Bristol basin, the long zone of limestone strata of the lower Carbon of France and Belgium enters Germany at Aachen and ends in the Ruhr. Further east, the carbonic limestones are replaced by the schistose-arenaceous facies of the culm, also present along the Rhine and developed in Hesse in the basin of the Dill river, a tributary of the Lahn. Upper Carbon begins near Aachen with a double syncline containing coal deposits. On the right of the Rhine, in the Ruhr, this land is also well represented and has been used for coal mining near Bochum, Essen, Dortmund and elsewhere. At the south of the Schistosi Mountains of the Rhine there is the Saar basin, important for its mineral wealth and its current geographical-political position.

Much less extensive is the top carbon of average Germany and not all with coal deposits. On the other hand, carbon is much more important in Silesia, where in SW. of Breslau there is the Carboniferous territory of Waldenburg. Separated from the culm by means of a manifest discord, here is the upper Carbon with its three planes. Even greater is the importance of the deposits in Upper Silesia, of which only a part has remained in Prussia. In southern Germany there is no land of this system except in the Black Forest.

An interesting peculiarity, also from an industrial point of view, is the position of the Permian salt deposits in the Germanic Lowland, in which they appear as enormous pillars wedged between the horizontal stratifications, always along lifting lines or axes of anticlines. The Permic in Germany occurs in two classic divisions: the lower one of the Rotliegende, terrestrial or limnic formation of conglomerates and red sandstones with cupriferous schists, and the upper one of the Zechstein, formation of the inland sea limestone-dolomitic, marly, with gypsum, salts potassium and copper minerals, rock salt and conglomerates at the base. For this clear double division, the system is also called Dyas. The layers of Rotliegende are located in a large area between the Saar and the Nahe and continue on the right of the Rhine along the Taunus, into the Odenwald, into the Main valley upstream of Hanau and into the Wetterau. Scarce in SW Germany, the Rotliegende is very developed in the Thuringian Forest and is associated with the igneous rocks that are also found in the Harz. On the northern edge of this mountain and in Oppenau in the Black Forest, the strata contain coal. The Rotliegende is also represented in the Mansfeld and Halle area. In the Kyffhäuser Mountains the sandstones and conglomerates contain trunks of silicized conifers. in the Ore Mountains the Rotliegende is extended, which is also found in Silesia on the slopes of the Giant Mountains and in the Waldenburg area.

The Zechstein, the most recent division of the Permian, is much less powerful than the Rotliegende and forms rather thin edges around the oldest mountain nuclei, occupying the interposed lowlands. Thus along the northern slope of the Giant Mountains, along the Harz, the Thuringian and Franconian Woods, on the eastern side of the Schistose Mountains of the Rhine, in the Spessart and Odenwald. The Zechstein is also found near Heilbronn and Heidelberg and reappears in the Bavarian Palatinate near Albersweiler and Bindersbach with some characteristic fossils. It is also noteworthy that of Zechstein there are residues superimposed on the oldest massifs (in the southern and middle Thuringian Forest). In the subsoil of northern Germany then it must have a great extension, as evidenced by the mining drillings that were made there. The Zechstein it is in fact rich in very important minerals. The deposits of rock salt, silvina, kieserite and carnallite in Germany are not found anywhere on the globe: they extend from the Dutch border to Posnania and from the lower Elbe to southern Hesse, and their power reaches 130 m. in Wesel, 228 in Salzungen, 380 in Stassfurt, 460 in Aschersleben. In Stassfurt and in deposits of this type (around Magdeburg, the Harz and Hanover) the powerful deposit of potassium salts overlying the rock salt is characteristic. In Hessian-type deposits (such as along the Werra and the lower Rhine), potassium salts are interspersed in several thin layers in the rock salt. In the lower one are the cupriferal schists with remains of fish and terrestrial plants which are typically found in the territory between the Harz and the Thuringian Forest and in Lower Hesse (Richelsdorfergebirge); similar deposits are also found on the eastern edge of the Schistosi Mountains of the Rhine. Along with the important copper ores, galena, pyrite and native silver are mined. On the edge of the Thuringian Forest are powerful banks of bryozoans that take the form of high Dolomite bastions. At the On the edge of the Thuringian Forest are powerful banks of bryozoans that take the form of high Dolomite bastions. At the On the edge of the Thuringian Forest are powerful banks of bryozoans that take the form of high Dolomite bastions. At theMiddle and upper Zechstein belong the clays and gypsum (the latter often cavernous) which are accompanied by salt deposits formed by evaporation in the sea of ​​the time.

The Permic volcanic activity had completely ceased with the beginning of the Mesozoic, so much so that no eruptive traces are found in the rocks of this era and overall, also with regard to the tectonic dynamism, the Mesozoic was a peaceful era. Different from the Alpine Trias, which has oceanic facies, the Germanic Trias, similar to the Permian, constitutes a formation that the more our knowledge of the way in which sedimentation occurs in the semi-arid regions of the globe progresses, the more opinion is made. of those who believe it originated on emerged land (in lake basins, along rivers and due to the action of the wind: Buntsandstein and Keuper) and in an inland sea (Muschelkalk). It took the name of Trias from the fact that in Germany it is clearly tripartite in a lower section made up of variegated sandstones (Buntsandsteingrès bigarrée dei Francesi), in an average of shell limestone (Muschelkalk), in an upper section called iridescent marl (Keupermarnes iriséesdei Francesi) very distinct also paleontologically. The Trias occupies a large area of ​​middle and southern Germany, from the hills of the Weser to the Swabian-Franconian Jura, from Saxony to Luxembourg. In Thuringia, Hesse, Franconia, Swabia is the predominant formation. Also in Silesia, in the territory of Magdeburg, in Brunswick, in Hanover, around Trier, the Triassic occupies considerable surface and continues, in Lorraine and Alsace. In the northern lowland, strips of Trias emerge from the Quaternary deposits, as in Rudersdorf near Berlin, in Lüneburg; and the island of Helgoland is the northernmost part where the Germanic Trias is found.

In the predominantly clayey-arenaceous formation, also known as variegated sandstones, there are sometimes powerful layers of gypsum (in Thuringia), marls with salt deposits (in Harzburg, Schöningen and other places in the Harz). The nature of these and other materials, the lack of sea shells and the singularity of the physical imprints preserved in the stratiform pages, support the opinion that the dry climate that allowed the formation of gigantic deposits continued to dominate the area of ​​present-day Germany. of salt in the previous Zechstein period, so that in the early Triassic period conditions existed in Germany comparable to those that in the present epoch occur in the Tarim basin. Based on the petrographic differences, the variegated sandstone formation is divided into three sections, the upper of which is known as Röt. The middle Trias, unlike the lower and upper ones, is an essentially calcareous stratigraphic series, hence the name of Muschelkalk (shell limestone). It also contains gypsum marl with rock salt deposits (Heilbronn, Kochendorf, Stetten di Hohenzollern, Erfurt) and in Upper Silesia the lower dolomites contain important minerals (limonite, galena, calamine). Its fauna of lamellibranchs and brachiopods, whose shells form entire schools with a few other zoological groups (crinoids, corals, sponges), has a Mediterranean sea character. As for the influence on the surface conformation, it is remarkable that the horizontal stratifications form monotonous karst plateaus, engraved by narrow and deep valleys, and that the minor clods of shell limestone appear in the form of ramparts that with very steep walls descend on the valleys.

The upper group of strata of the Trias is formed by Keuper, or iridescent marls, mainly red in color, associated with deposits of chalk, light-colored sandstones, impure limestones and dolomites and, in the upper level, impure litantrace. The largest extension of the Keuper it is given in Franconia and in Swabia; it also occupies considerable surface area in Luxembourg, in the center of the Thuringian basin, in the Teutoburg Forest and in the hills of the Weser, in the territory between Brunswick and Halberstadt and in Upper Silesia. Overall, it can be said that the area of ​​this formation slightly exceeds the political borders of Germany. Surely marine of origin, they are the lower and upper sediments, but the main part of the series, whether the stratifications containing coal, the chalky ones, and the saliferous ones, must be of continental origin, that is, they must have been deposited in brackish swamps and by work of rivers.

The Jurassic lands, or Jura, have a much smaller extension than the Triassic, which are distributed in three main areas, in Swabia and Franconia, in the NW part. and in Upper Silesia. The upper Jura (Malm) of southern Germany, where up to the upper Portlandian the sediments are purely marine, differs from that of the northern part where the lagoon formations already prevail. Cretaceous soils found in the territory of N. of the Harz, in Brunswick and in Hanover, in the Teutoburg Forest and on the upper Bober tributary of the Oder, have an even smaller extension than the Jurassics in Germany.

In Swabia and Franconia the Jurassic lands form a large band that has the figure of an L lying on the left of the Danube, with the top at Regensburg and which corresponds to the relief of the Swabian-Franconian Jura. The Jurassic to the NW, from Helmstedt and Quedlinburg extends westwards as far as the Teutoburg Forest, forming a discontinuous series of elliptical strips or areas, the most notable of which is given by the heights of the Weser that the river cuts through, forming near Minden the Vestfalica Gate. In the stratigraphic series we can distinguish the Black Jura, the Brown Jura, the White Jura.

The lower Jura, or Lias, is also called the Black Jura due to the presence of bitumen in the limestone layers and in the shales: it is distinct from the fossil remains of many reptiles, fish and cephalopods; the middle Jura, or Dogger, is also called Jura Bruno, clays with Leioceras opalinusred-brown and whitish sandstone banks, “blue” limestones, clays and marls, oolithic limestones. The Upper Jura, or Malm, also called the White Jura, is made up of layers of clay and marl and white limestone, the rugged forms of which contrast strongly with the softer ones of the Black Jura and the Brown Jura. They are almost completely organogenic. Such are also the coral and spongiarî limestones and the dolomites: on the whole, shallow sea sediments. In the lithographic limestones belonging to this section, the famous fossil bird (Archeopteryx) was discovered near Solenhofen, with wings equipped with clawed fingers and a long tail of vertebrae.

The Cretaceans follow the Jurassic soils, which in Germany were distinguished with the particular names of Quadersandstein (dice sandstone), Planerkalk (thin-layered whitish limestones) and Hils (limnica facies sandstones). They are clearly separated from the Jurassic, which depends on the fact that the presence of the Lower Cretaceous always coincides with a transgression, as a result of which the most ancient Cretaceous layers, made up of conglomerates, lie in discord on the most ancient formations. This, on the other hand, does not occur in southern Europe, where the transition from the Jurassic to the Cretaceous takes place insensibly.

The Lower Cretaceous period has scarce extension in Germany (territory in N. of the Harz, Brunswick, northern Hanover, Deister, Schaumburg county, hills of the Weser and Teutoburg Forest). The Weald, Limnic and Deister sandstones contain remains of iguanodons, crocodiles and plesiosaurs; the clastic rocks (Hils) of NO Germany. instead they belong to the Neocomian (Lower Cretaceous marine); al gault, or Albian, the N. stratifications of the Harz, Brunswick and Hanover.

Between the lower Cretaceous and the upper there is a clear separation corresponding to a powerful transgression that occurred slowly. The Upper Cretaceous is represented in Germany in six main areas: between Aachen and Maastricht (Senonian), NW Germany. (Westphalia, Teutoburg Forest, Weser hills, around Hanover, in Brunswick, Goslar, Halberstadt), in Saxony (dice sandstones of the Elbe plateau and also the stratifications of Lower Silesia and those of the Bavarian Forest between Baireuth Amberg, Regensburg and Passau), in Upper Silesia (Oppeln, Leobschütz), in the Baltic coastal region (Rügen, mouth of the Oder, Pomerania, Mecklenburg, Holstein, Lüneburg, in Western and Eastern Prussia). As is known, under the name of Neozoic or Cenozoic all the rocks that formed after the end of the Cretaceous period are included: the formations of this long era are divided into two great systems, Tertiary and Quaternary.

The paleogenic terrain in Germany is represented by sandstones in the Bavarian Alps (Kressenberg, Allgäu) and the close relationship between these sediments and those of the Paris Basin suggested that the sea that stretched over the latter communicated with that of Upper Bavaria. In northern Germany then the perforations made under the mantle of glacial materials revealed the existence of the Paleocene and revealed a marine transgression from Denmark and Schleswig-Holstein to Mecklenburg, Pomerania and northern Hanover. Almost this was the extension of the sea in the subsequent Mesonummulitic, or Eocene period proper. The sea sent arms towards S., within the emerged part of present-day middle Europe. The marine Eocene is scarcely represented in the Germanic region, where it is essentially limited to the northern coastal part (Schleswig-Holstein, Lauenburg, Mecklenburg, Pomerania). Then there are Eocene stratifications in the Bavarian Alps (Kressenberg and Grünten) and in the Swabian and Franconian Jura. The origin of amber dates back to this period, whose high paleontological interest is no less than its historical and economic one. It is a fossil resin, which was produced from the Eocene forests of Pinus succinifera and which is transported as a secondary deposit in the Oligocene blue soil of Samland. It includes many insects (2000 species) and araneids and remains of other plants (over 100 dicotyledons). The lignites of Helmstedt, Aschersleben, Zeitz, Halle, Leipzig and Messel and some sedimentary strips of eastern Hesse are also ascribed to the Eocene today; as in all these localities, even in southern Germany, there are only lake deposits. Some contain iron ore.

The extension of the marine Neonummulitic (Oligocene) is considerable; which depends on the transgression that occurred in Germany in this period. The whole area corresponding to northern Germany, up to Stargard, Kottbus, Leipzig, Aschersleben, Kassel, Osnabrück and Düsseldorf was occupied by the sea which also extended to the east and west. The transgression reached its maximum extent in the Middle Oligocene, when between the great southern sea of ​​the Tethys and the northern one, there was a communication that corresponds to the current position of the valleys of the Rhine, the Saone and the Rhone. Some deposits of lignite, potassium salts and iron minerals belong to this period. The second half of the Tertiary or Neogene era is characterized in Europe by the formation of the largest current mountains. And this happened mainly in the most ancient Neogenic period, called Miocene. In this period the sea had withdrawn from northern Europe and in Germany was reduced to a restricted area between present-day Friesland and present-day Mecklenburg. The Mainz basin, after an invasion of the sea in the early Miocene, had also become a brackish inland basin. Some lignite deposits in the Rhön, the Lower Rhine, Brandenburg, Posnania, Silesia and Saxony are Miocene. With the close of the Miocene, a new sea retreat took place throughout Europe and the whole area corresponding to present-day Germany had already emerged, so that the marine Pliocene is represented only by the limonite sandstones of the island of Sylt. Instead, river and limnic sediments with lignites are extensive, in the Wersterwald,

According to, the Pliocene has a limited extension in northern Germany, while in the average Germany the limnic and fluvial formations of this period are very extensive. But much more important in Germany is the Quaternary, with its alluvial, glacial and aeolian deposits. The most ancient form the so-called diluvial, or plistocene, the most recent the alluvial, or holocene. The glaciations also exerted a very important morphological action. The glaciers of the Alps that descended through the valleys of the northern side, gathered at the foot of the same to form a single imposing layer of ice. In the country opposite the Alps, alluvial deposits are also important. According to Penck and Brückner, there were four Alpine glacial epochs, separated by three interglacial periods. The highest floods are the river deposits that occurred during the Gunzian glaciation (älterer Deckenschotter), those that lie at a lower level are contemporaneous with the Mindelian glaciation (jüngerer Deckenschotter) and even more deeply located are those that correspond to the Rissian glaciations (Hochterrassenschotter) and Wurmiana (Niederterrassenschotter). These positions are explained by the fact that during each interglacial period the ablation water currents of the receding glaciers exerted a powerful erosion, affecting alluvial terraces.

Without wider comparison, it was the area occupied by the continental glaciation in northern Germany, which was covered with rock debris removed from Fennoscandia. They are non-layered and chaotic materials of deep moraine (GeschiebemergelBlocklehm of German geologists) and large frontal moraines crossing the lowland, where the glacier made long pauses; outside the morainic arches, the ablation waters deposited stratified floods (sands and gravels). Large erratic boulders, such as that of Belgard in Pomerania which measures 600 cubic meters. In the lowland, evidence of three distinct glacial expansions has been found up to now: the oldest glacial, which was preceded by a preglacial period, is called Elsterian, the middle is called Saalian, the more recent Vistolian; between the first and second glaciation and between the second and third there was an interglacial period. In the space that was not covered by ice between the great Northern European and Alpine ice sheets, the Quaternary is represented everywhere by river floods, sands, silts and löss. The löss forms vast extensions to S. of the southern end of the Northern European glaciation, in the republic of Saxony and in the Prussian province of the same name, in Thuringia, Franconia and Swabia, generally for the power of 8-12 m., And does not exceed, for mostly, the height of 300 msm.

Germany Lithological Composition of the Soil