Rügen chalk
Rügen chalk , also Rügen writing chalk , is the common name for a very pure, very fine-grained, white, friable and highly porous limestone of the highest Upper Chalk ( Maastrichtian ). He is among others in the cliffs of the steep coast of the Jasmund in the northeast of the island of Ruegen minded ( "White Cliffs").
In addition, Rügener Kreide is the trade name for the white pigment that is extracted from these limestones.
stratigraphy
Lithostratigraphically, the Rügen chalk belongs to the Hemmoor formation of the writing chalk group and is eliminated as a Rügen member within this formation . Chronostratigraphically , the Rügen member falls into the late lower to late upper Untermaastricht (approx. 70 million years before today).
features
Chalk limestones are often layered. The Rügen chalk, however, is unlayered and massive. The extremely fine grain and very low cementation associated with high porosity are remarkable . The low cementation and the high porosity mean that the rock can soak up a lot of water. While dry Rügen chalk is relatively crumbly but still brittle , water-saturated Rügen chalk is more plastic - almost like damp clay - and can be cut with a knife. Like many other limestones of the Upper Cretaceous, the Rügen chalk has a very high content of calcium carbonate (CaCO 3 , "carbonate of lime"). With the Rügen chalk it is at least 97%. The vast majority of calcium carbonate is in the form of micrometer-sized low-Mg calcite platelets, so-called coccoliths , which are remnants of unicellular , planktonic calcareous algae, so-called coccolithophores. The calcareous algae lived around 70 million years ago in the light-flooded surface water of a sea that covered northern Germany. After their death, they sank to the sea floor and over time they formed huge deposits of limestone mud. This lime sludge is handed down today in the form of the Rügen chalk.
Another typical feature of the Rügen chalk is its high content of flint concretions . These are usually formed as tubers and enriched in individual horizons. Sometimes there are also flat formations of different thicknesses. Particularly large, cylindrical flint concretions are known as "Sassnitz flower pots" (see also → Paramoudra ). The silicon dioxide (SiO 2 ), from which the flint stones were formed, originally comes from unicellular diatoms ( radiolarians , diatoms ) that lived together with the calcareous algae in the sea of chalk: After the coccolith sludge containing radiolarians and diatoms had been deposited, the SiO 2 of the diatoms dissolved Water that circulated in the pore space of the sediment and was precipitated again elsewhere in the sediment . These places are represented today by the flint stones. Since the flint is significantly more resistant to weathering and erosion than the limestone, it accumulates on the beach of the chalk cliff and is transported by waves and currents to neighboring areas of the coast during storms and deposited there. The flint fields near Prora are particularly well-known in this regard .
Occurrence
In the northeastern part of the island of Rügen, on the Jasmund peninsula , there are extensive chalk deposits. The best known are probably the "Rügener chalk cliffs" on the cliff coast in the vicinity of Sassnitz (see also → Stubbenkammer , → Königsstuhl ). These coastal formations are part of the Jasmund National Park and are under strict nature protection.
But also in the hinterland of the Jasmund, chalk lies beneath a 1 to 10 m thick surface layer in the subsoil. There are many quarries and opencast mines, almost all of which have since been abandoned due to inefficiency or for reasons of landscape protection. Overflowing with water, they can be seen in aerial photos of Jasmund as small and large lakes and ponds (the currently largest is the “Kreidesee Wittenfelde”). Even in the urban area of Sassnitz you can still see old chalk quarries, but they date from the beginning of the 19th century. The chalk is currently being mined in the Promoisel opencast mine .
history
General
As early as 1720, chalk was mined in the Granitz for the production of quicklime (CaO) in quarries . The foundation stone for the Rügen chalk industry was only laid in the first half of the 19th century by the entrepreneur and natural scientist Friedrich von Hagenow (1797–1865). In 1832 he leased the chalk quarries in the Stubnitz , and in the same year he opened a slurry mill in Greifswald . At that time, the raw chalk was taken by ship from Jasmund to the Hagenow'sche Schlämmerei. By slurrying, the raw chalk was separated from the undesired rock components such as flint (flint, see above ) and fine-grained impurities (so-called grand ), and the same principle is still used today. At the time of Hagenows and for a long time afterwards, however, the mining and processing of chalk was almost exclusively done with human muscle power, and the work was very physically demanding.
From the late 19th century, the fishing village of Sassnitz, located in the immediate vicinity of the Stubnitz, slowly developed into a center of the chalk industry, not least because the majority of the chalk pits were on the Jasmund. A fierce competition developed between the individual slugs. This was one of the reasons why von Hagenow had to give up his business in 1850. That is why 17 companies with 23 slurry companies formed a cartel in 1899 and set binding production and production quantities and prices for all members. In 1928, around 500,000 t of raw chalk from the Jasmunder quarries in Martinshafen on the Great Jasmunder Bodden and in Sassnitz were loaded. With 80,000 t of handling, chalk production on the Jasmund only played a subordinate role at that time. Purchasers of raw chalk above all that were Portland cement factories in Wolgast , Lebbin and Szczecin . So then included some pits and Schlämmanlagen on the Jasmund directly the Szczecin Portland cement factory A.G. of Martin Quistorp . The other large chalk and cement producer and the most important player in the Rügen chalk cartel was the Pommersche Industrieverein a. Founded in 1872 by Johannes Quistorp . A.
With the collapse at the end of the Second World War, chalk extraction and processing came to a temporary standstill. Some facilities, including the chalk cable car to Sassnitz harbor, were dismantled and taken to the Soviet Union as war compensation. In addition, the fact that the island of Rügen belonged to the Soviet occupation zone and later to the GDR meant the elimination of private-sector structures in the Rügen chalk industry for the next 45 years. It was only during this period that modern technology completely replaced strenuous physical work in many areas. Since chalk was soon in demand again as a raw material with the reconstruction, after 1945 a total of 19 chalk quarries started operations on Rügen, which from 1957 had been merged in the VEB Vereinigte Kreidewerke Rügen . Already before 1945, mining had stopped in the oldest quarries on the eastern edge of Jasmund and near Lohme , as well as in the quarries from Dumsevitz , Rosengarten and Altkamp on southern Rügen. With the completion of a large and modern chalk works in Klementelvitz between Sassnitz and Sagard , many other smaller chalk quarries were closed after 1962 and the company was renamed VEB Kreidewerk Rügen . During the GDR era, the company belonged to various institutions. So it was temporarily subordinate to the council of the Rostock district , then belonged to the association of VEB Bindebaustoffe Halle and then to VVB Zement Dessau , which was later renamed VEB Zementkombinat Dessau (ZEKOM). In 1984 the legal independence of the VEB Kreidewerk Rügen was finally abolished and it was assigned to the VEB Zementwerke Rüdersdorf as part 6 . Under favorable conditions, the Klementelvitz chalk works, which after commissioning was considered one of the most modern chalk works in Europe, achieved an annual production of 185,000 tonnes of whiting and 55,000 tonnes of Grand.
In the course of the economic upheavals as a result of the political change in the GDR in 1989 and 1990 , the VEB Zementwerke Rüdersdorf was taken over by Readymix AG and the chalk factory in Klementelvitz was spun off, converted into a GmbH and initially remained with the Treuhandanstalt . The operation of the mine railways for the transport of raw chalk from the Wittenfelde opencast mine north of Klementelvitz, the only active chalk mine on Rügen at that time, was discontinued. On August 13, 1993, after all property ownership issues had been resolved, the Kreidewerk Rügen GmbH was taken over by the Vereinigte Kreidewerke Dammann KG and thus the Swiss Omya AG . By then, the company's sales had dropped to just 25,000 t. Omya invested a total of almost € 50 million by 2010 and built a state-of-the-art facility for chalk production - from dismantling to loading. At the end of the 1990s, the Wittenfelde open-cast mine was shut down and instead the Promoisel open-cast mine was put into operation approx. 1 km further west. Around 25 million t of raw chalk was available there at the start of mining. The freshly broken chalk now arrives at the factory via a 2 km long conveyor system and is processed there using the new wet processing technology to make whiting chalk in different finenesses. The annual production of the plant is now up to 500,000 t. In 2009, the planning approval decision was issued for the future Goldberg / Lancken-Dubnitz mining field south of Klementelvitz, in which 35 million t of chalk may be mined by 2117.
Extraction
In the 19th and partly in the early 20th century, the chalk had to be knocked off a steep demolition wall with pickaxes and driven on carts to the so-called agitator . In large vats in which iron hooks rotated, the chalk was slurried with the addition of water. During this work step, the coarsest parts, mostly flint, were separated off. The chalk suspended in water, also called chalk milk or chalk cloudy , was passed through so-called sedimentation channels , on the bottom of which the finer impurities, the grand , were deposited. The chalk cloudy, freed from the Grand, finally reached the settling basin, in which the finest particles still in suspension settled into a 30 cm thick layer. The now no longer cloudy water was drained and the basin was filled with fresh chalk cloudy so that the fine particles could again settle. The whole thing was repeated until the sediment had reached a thickness of approximately 1.5 meters. The finished fine chalk still had a water content of 30 to 35%. This heavy, thick pulp was now knocked out , i. that is, it was shoveled into carts from the sedimentation basins. The workers who carried out the work from dismantling to knocking out were called Schlämmer .
Other workers, the so-called formers , transported the wet chalk with the carts to the drying shed , shaped it into shovel-sized pieces and laid them out there to dry. The fittings had to be shifted several times during the drying time of around four weeks. With a residual moisture of approx. 5%, the chalk was ready for dispatch at the time.
From the turn of the 19th to the 20th century, the mining and processing of chalk became increasingly industrialized, as a result of which the production volume of raw and whipped chalk increased significantly. Around a dozen excavators were already in operation for chalk mining before 1945. The raw chalk came from the Jasmunder quarries either via a railway line, the chalk railway, to Martinshafen near Sagard (there are also old quarries there) or by cable car to the Sassnitz harbor. The chalk railway forked in the direction of the mining area into a northern and a southern section. The southern line ran from Wittenfelde via Klementelvitz and Quatzendorf to Marlow, where it merged with the northern line from Gummanz. The Rügen Kleinbahn also played an important role in the transport to the ports . To relieve the ports of Sassnitz and Martinshafen, the so-called chalk bridge in Wiek auf dem Wittow was completed in 1914 for loading chalk onto barges, which was reopened 100 years later as a "floating promenade".
Production continued for some time after 1945 using pre-war technology. In order to increase the delivery rate and at the same time to be able to guarantee a constant quality of the whiting chalk with a residual moisture of about 0.5% and grain sizes not exceeding 63 µm, new technologies were developed and a new chalk plant in Klementelvitz was designed and sold from 1958 for 30 million marks ( DDR) built. In this context, the heavy physical work in the wall was completely replaced by the then modern conveyor equipment such as the UB 80 excavator, a GDR standard excavator from the 1960s and 1970s. Both the raw chalk and the spoil were transported by rail. With the completion of this plant in 1962 (initially trial operation, regular production from 1963), the production time from dismantling to packaging was reduced to just 80 minutes. Until then it was up to 80 days.
The chalk lorries and excavators later became larger (UB 162-1), and 20 m³ lorries from open- cast lignite mining were also used on a trial basis after the tracks had been converted accordingly. Depending on the soil conditions, heavy trucks were also responsible for transporting the overburden, and special excavators were used to relocate the track sections . Some of the chalk was also prepared in the open pit using a "mobile whipping device".
use
Like any other substantially pure limestone can marvel at the chalk for both cement production and the production of agricultural lime to use. A relatively modern area of application for limestone is flue gas desulphurization , and inferior quality Rügen chalk is also used for this purpose, especially in the Rostock and Jänschwalde coal-fired power plants : Sulfur oxides (SO X ) react with calcium carbonate to form gypsum (CaSO 4 ) and carbon dioxide (CO 2 ) . While the carbon dioxide escapes into the atmosphere, the gypsum is reused in the construction industry.
A special raw material that results from the processing of the raw chalk is the whitewashed chalk (see above ). Even before 1945 it was taken by train to Berlin , Bremen , Hamburg , the Ruhr area , Breslau and Stettin , where it was processed into products for the electrical, paint and cosmetics industries. From the 1960s, in contrast to pre-war production, VEB Kreidewerk Rügen delivered whiting chalk in 3 types of grain as required - "Malkreide 60", "Feinkreide 40" and "Mikrotherm 20". Under the name "Drei-Kronen-Kreide" (nostalgic name from the Swedish times), whitewash chalk was an important export item of the GDR, which was delivered to 40 countries. Customers were still the rubber and cable industry, factories in the paint and paint industry, as well as the cosmetics and pharmaceuticals industries. Since 1974, whitewash chalk has been processed as a white pigment into the glued wall paint "GW 12" in the Quatzendorf operation . Around 8,000 t of it ended up in the retail trade every year.
Contrary to what the name "writing chalk" (see above ) still used today in lithostratigraphy suggests, the Rügen chalk is not and was not used for the production of school and blackboard chalk . At least in Central Europe, this is made exclusively from plaster .
With the advent of the wellness and alternative medicine movement, Rügen mud chalk is increasingly being offered as so-called healing chalk for mud packs and other applications.
literature
- Heinz Lehmann, Renate Meyer: Rügen A – Z (Arkona - Zudar). Wähmann-Verlag, Schwerin 1976, p. 46
- Mike Reich, Peter Frenzel: The fauna and flora of the Rügen writing chalk (Maastrichtium, Baltic Sea). Archive for history of history. Vol. 3, No. 2, 2002 ( ResearchGate ).
Web links
- Literature on Rügen chalk in the state bibliography MV
- On the history of the Rügen chalk. on the website of the Vereinte Kreidewerke Dammann KG
- Christine Damerow, Karlheinz Markmann: Excursion guide Kreidebruch Gummanz. Chalk educational trail / chalk museum Gummanz, project of the Association of Friends and Supporters of the Jasmund National Park V.
- Website of the Gummanz chalk museum
Individual evidence
- ^ Birgit Niebuhr: Hemmoor formation. ( Memento of the original from March 4, 2016 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. LithoLex [online database], data set no .: 2008077, BGR Hannover, last updated on March 12, 2010, accessed on December 14, 2014.
- ↑ Jasmund: Consequential misunderstanding. BUND website, accessed on December 14, 2014.
- ^ A b Hans Radant: On some problems from the history of the monopoly associations of the Rügen chalk industry. Yearbook of Economic History. Vol. 5, No. 2-3, 1964, pp. 215-239, doi : 10.1524 / jbwg.1964.5.23.215
- ↑ Wulf Krentzien: Sassnitz on Ruegen - yesterday and today. The Back then series. European Library, Zaltbommel 2011 (unchanged reprint of the 2003 edition), ISBN 978-90-288-6720-8 .
- ↑ a b c d Botho-Ekkehard Hendel: The company Kreidewerk Rügen GmbH. In: 20 years of the Stralsund Mining Authority. Ministry of Economics, Labor and Tourism Mecklenburg-Western Pomerania, 2010, pp. 19–21 ( online ( memento of the original dated December 24, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and Archive link according to instructions and then remove this note. ).
- ↑ Wulf Krentzien: Sassnitz in transition: 1945 to 2007. Sutton Publishing, Erfurt in 2008, ISBN 978-3-86680-302-2 , page 98
- ↑ a b chalk lime and silica chalk. Website of the State Office for the Environment, Nature Conservation and Geology Mecklenburg-Western Pomerania.
- ↑ Sagard Chalk Quarry. Data sheet with photo on Kleks-Online.
- ^ Historical chalk bridge opened in Wiek on Rügen. Report on Welt.de from July 18, 2014, accessed on December 19, 2014.
- ↑ Kreidewerk Klementelvitz. Data sheet with photo (from 1999) on Kleks-Online.
- ^ A b Lehmann, Meyer: Rügen AZ. 1976 (see literature ), p. 46.
- ↑ Rügen chalk popular with coal-fired power plants. Märkische Oderzeitung from May 20, 2008.
- ↑ Quatzendorf chalk works. Datasheet with photos on Kleks-Online.
