Geology of the Münsterland

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The geology of the Münsterland deals with the geological development and the structure of the subsurface of the Münsterland. It can be traced back around 400 million years to ancient times. The Münsterland in the geological sense is an area that is referred to in the literature as the Münsterland Chalk Basin or the Westphalian Upper Chalk Basin , and goes far beyond the region that is now commonly known - by no means clearly - as the Münsterland . The major geological unit considered here includes the entire Westphalian Bight including large parts of today's Ruhr area ( Emscherland , Westernhellweg ) and Hellwegbörden up to the heights of the Haarstrang in the south. It extends in the east over the Paderborn plateau to the Egge , in the northeast it includes the Teutoburg Forest and parts of the Wiehengebirge . In the west it borders on the Lower Rhine lowlands , to which parts of the Westmünsterland already belong and which has its own geological history .

Geological development

Devon

Today's largely flat Münsterland landscape gives only a little idea of ​​its eventful history, which can be traced back to the Devonian geological age . Back then, around 400 million years before our time, the Münsterland was part of an ocean floor. The rocks formed from the sediments of this sea lie at great depth today. The Münsterland 1 borehole from 1961/62 in the Baumberge near Billerbeck encountered the first layers of the Upper Devonian at a depth of more than 5500 meters .

Carbon

Above the sediments of the Devonian are the coal- bearing rocks from the Carboniferous Period (approx. 360-300 mya ). These are significantly lower in the central Münsterland than further south in the Ruhr area or further north in the Ibbenbürener district . They were deposited in a fore-depth of the Rhenish Slate Mountains , which were unfolded into high mountains in the course of the Variscan mountain formation . In the course of the progressive subsidence of the fore depths, they were regularly graveled and swamps with extensive peat horizons formed , which are the basis of today's hard coal deposits. The Münsterland 1 borehole penetrated a total of 98 seams, albeit only slightly thick, at depths between 1853 and 3678 m.

Shift gaps in Permian, Triassic and Jurassic

The absence of sediment layers from the Permian , Triassic and Jurassic eras that followed the Carboniferous shows that the Münsterland was an erosion area and thus part of the mainland for a long time, around 200 million years. During this time there was a tropical to subtropical climate; even if there is no fossil evidence, it can be assumed that large dinosaurs also lived in the Münsterland. A good 250 million years ago, an arm of the North German Zechstein Sea penetrated along today's German-Dutch border as far as the Moers area. The flat lagoon , which keeps falling dry, left behind a large salt pan , the rock salt of which is found in Westmünsterland 1500 meters below the surface and is up to 250 meters thick there.

chalk

Cretaceous blocks made of Baumberger sandstone
Outcrop of Halterner Sande on Hünsberg near Coesfeld

Today, between Rheine , Borken and Dorsten in the west, the Weser Uplands in the northeast and the Hellweg area in the southeast, sedimentary rocks that can be assigned to the Upper Cretaceous (approx. 100 - 66 mya) can be found embedded in the hollow formed by the Carboniferous basement . One speaks therefore of the Münsterland chalk basin or the Westphalian upper chalk basin . It was only in this section of the earth's history that the basic structure of the Westphalian Bay emerged as a result of the tectonic processes associated with the beginning of the Alpine mountainous formation .

Due to strong volcanic activity, the carbon dioxide concentration in the Cretaceous atmosphere was high. A pronounced greenhouse effect caused temperatures to rise, and the climate in Münsterland was subtropical. Since the polar caps were not icy, the sea level was 70 meters higher than today for this reason alone. As a result of the unusually rapid ocean floor spreading , mid-ocean ridges made up a larger proportion of the ocean floors than they do today. As a result, a lot of seawater was displaced from the deep ocean basins into the peripheral areas of the continents. There were therefore very extensive shelf or epicontinental seas in the late Cretaceous period so that the total area of ​​the oceans was significantly larger than it is today. This additionally intensified the greenhouse effect in the long term, as water has a high heat capacity . In addition, a decrease in land area reduces the extent of carbon-consuming chemical weathering of continental rocks.

In the end of the Lower Cretaceous around 110 million years ago, the coast lay roughly on a line from Arnhem via Rheine to Bielefeld . During the Albium (112.9 - 100.5 mya) the area sank, the sea broke into the "Westphalian" basin and penetrated to the edge of today's Sauerland. Throughout the Upper Cretaceous, the sinking hollow of the Münsterland was a warm shelf sea, of which today marl, limestone and sandstone in layers up to 1,800 meters thick herald. The sea floor sloped from southwest to northeast, so it was much shallower in the southwest. In the Cenoman (100.5 - 93.9 mya), the most distant section of the Upper Cretaceous, the coastline ran approximately from Duisburg via Mülheim, Essen, Bochum and Dortmund to the area south of Paderborn. The Essen green sands , which can be found in the southwestern Ruhr area, and the Rüthener sandstone originate from this time . Further north, the Cenomanian sediments are covered by later deposits. Only on the other side of the Westphalian Bay, along the Teutoburg Forest, do they surface again in the form of limestone, marl-limestone and marl rocks.

From the adjacent Turon (93.9 - 89.7 mya) come the Anröchter stone and the Werler green sandstone , which is found between the hairline and the lip. The subsequent epoch of the Coniacs (89.7 - 86.3 mya) left behind the gray clay marl layers known as the Emscher marl.

In the south-west, between Recklinghausen , Dorsten , Borken and Coesfeld , so-called Haltern sands were deposited in layers up to 250 meters thick during the santonium (approx. 86.3 - 83.6 mya) . The Halterner sands are a pore aquifer first class and indispensable today basis of the drinking water supply of the southern Münsterland and northern Ruhr area.

The youngest rocks of the Cretaceous period are now extensively eroded. Sediments from Campan (83.6 - 72 mya) are only found in the central Münsterland in the higher elevations of the Beckum Mountains , where they have become the backbone of the Beckum cement industry, and the Baumberge ( Baumberger sand-lime bricks ). In Maastricht (72 - 66 mya), the last stage of the chalk, the subsidence processes ended, the sea was pushed back and the Westphalian Bay became continental again.

Paleogene and Neogene

The Leerbachopf , karst spring on the Schöppinger Berg

The second major shift gap in the Münsterland relates to the Paleogene and Neogene periods , which were combined in the old nomenclature to form the Tertiary (66 - 2.6 mya). From this time, apart from a few remains in the border area with the Lower Rhine lowlands under the ice age deposits, there are no more rocks close to the surface.

In the erosion area of ​​the Münsterland chalk basin, the centrally located tree mountains were formed as a result of the reversal of relief in a hollow structure of the upper campan during this geological age . This small mountain range is karstified in parts . The Nonnenbach has a stream shrinkage in the upper reaches . The source of the Leerbach and the neighboring Schwarthoffs source on the Schöppinger Berg with their relatively high pouring are considered karst sources . Kalktuffterrassen found in the upper reaches of the bomb Shrouded Aa . Also sinkholes are detected.

The sands of the Haltern strata, which were sedimented in the Chalk Sea, were demineralized and podsolized by chemical weathering in the hot and humid climate of the Tertiary up to a depth of 60–70 meters . At the height of the groundwater level, iron slabs have often formed in the fossil gley in areas near the river during this time .

Maximum ice extent (third stage) of the Saale complex (yellow line). During the Elster (blue line) and the last glacial period (red) the ice masses did not reach the Münsterland.

quaternary

Pleistocene

The Holtwicker egg
Pavement made of debris from the ground moraine in Legden

2.6 million years ago, at the beginning of the Pleistocene , which ushered in the Quaternary Age , the climate cooled down. Several cold periods led to massive advances by the Scandinavian inland ice towards Central Europe. During the Saale glacial period , the entire Münsterland lay under a thick layer of ice, which is said to have reached a thickness of around 300 meters near Coesfeld. The tree mountains and the Teutoburg Forest were completely overrun by the ice. The maximum extent of the ice reached as far as the northern edge of the Sauerland or far into the Lower Rhine Bay . At the latest with this ice advance, the last (possibly still) existing tertiary deposits were remodeled. At the same time, the ice masses ensured that the flow directions of the waters changed fundamentally in some cases. They had a serious influence on the deposition and erosion processes. The vegetation in front of the ice changed to a shrub and moss tundra . Cold-resistant, new animal species such as woolly mammoth , woolly rhinoceros and reindeer entered the Münsterland stage.

Erratic blocks from Scandinavia were transported to the Münsterland with the ice . Many of these boulders come to the surface when the soil is plowed or are exposed during construction work. A particularly large and well-known example is the Holtwicker egg , which weighs around 30 to 35 t . The largest boulder in western Münsterland is the “Gronauer Brocken” with a weight of 46.8 t and a volume of 18 m³, which was only encountered in 1993 during construction work. The stone pair David and Goliath near Glandorf is a probably broken stone that weighs around 70 t in total. This large debris is likely to be the largest known boulder in the entire Westphalian Bight.

The ground moraine , a mixture of gravel , sand , silt and clay , left behind by the ice after retreating , is an average of five to ten meters thick in the Kernmünsterland. Once it covered the relatively flat landscape, today it is only left in remnants like islands; mostly gray to yellow-brown in color, it is interspersed with Nordic debris of various sizes. The debris from the ground moraine was used in many places in the Münsterland to pave streets, driveways and courtyards.

A special relic from the Cold Age of the Saale, the origin of which has not yet been clarified beyond doubt, is the Münsterländer gravel sand pull . It extends as an 80 km long, wall-like elevation from northwest to southeast across the Münsterland. Today it is assumed with some probability that it is a cameo in the border area of ​​two branches of the Emsland Glacier, possibly above a previously existing Os at the glacier base. One of these glacier branches showed no more movement, while the other transported moraine debris against it with its meltwater. After the ice had finally melted, the rubble remained as a raised wall in the landscape. The cathedral hill supporting St. Paul's Cathedral in the middle of the city of Münster is part of the gravel sand train.

During the last glacial period , the periglacial Münsterland had a tundra climate ; the annual average was up to 15 ° C colder than the current conditions. Due to the low temperatures, the vegetation had largely disappeared, the exposed areas led to considerable wind displacement. Loess was able to settle again in sheltered places , for example in the tree mountains near Stevern and Tilbeck in layers four to five meters thick. The flowing waters in the Münsterland formed their low terraces during this time, which they cut into in the subsequent warm period. Here, too, after the cut of its own sediments, there was wind displacement to a lesser extent. The resulting drifting sand covers in many places the layers underneath from the Cretaceous period and the ground moraine from the Saale period.

Holocene

Today's landscape of the Münsterland is essentially a result of the Holocene , i.e. the last 10,000 years. The climate became warmer and more humid. When the glaciers melted back to Scandinavia, the vegetation in northern Germany changed. The initial grasslands were displaced by boreal mixed forest, which in turn was replaced by deciduous forests spreading northwards. Along the western border of the Münsterland, a high moor belt was created on soaked soils, primarily on the bed moraine of the ground moraine , which still forms the natural border with the Netherlands today. The largest moor area in the Münsterland was the White Fens between Coesfeld and Velen until the middle of the 20th century . Most of the former moors have now been peated and made arable. At most there are still raised bog remains such as B. the Schwatte Gatt . The Münsterland park landscape as we know it today is primarily a man-made cultural landscape.

Floors

In the Münsterland today, a multitude of different soils can be found, which have developed over time, also with anthropological assistance, as a result of different initial conditions (especially rocks, relief, climate and groundwater). Hildegard Dahm-Arens differentiates between eleven soil types that can be found in the area under consideration:

  • Rendzinen
Crossing from Rendzina - Braunerde to Pseudogley / Gley north of the Oldenborg near Laer
Rendzinen are soils of low thickness, which are often found as typical mountain and karst soils on rocks rich in carbonate or gypsum . In the Westphalian Bight you can find them in the central Münsterland on the slopes of the Baumberge and Beckumer Berge , but also in the peripheral areas of the Haarstrang and the Teutoburg Forest . Larger contiguous areas of Rendzina can be found in the area of ​​the city of Rheine on the Thieberg ; these occurrences stretch east through the urban area of ​​Rheines to the Teutoburg Forest and southwest through the area of ​​the Neuenkirchen community over the Bilker Berg in the Wettringen community to the area south of the Rothenberg , which is, however, free of rendzina.
The humus-rich, crumbly upper layer of the rendzines soon merges into the underlying Upper Cretaceous original rock ( limestone , marl limestone, limestone marl), which is usually only slightly weathered. The stony, drought-sensitive soils, which are often at risk of erosion due to their hillside location, are often made up of (deciduous) forests or are used as undemanding grassland. They are not suitable for intensive agricultural use.
  • Base-rich brown earth soils
On the plateaus of the Baumberge and Beckumer Berge as well as on the heights and the middle and lower slopes of the Paderborn plateau , brown earths rich in bases determine the picture. These are medium to deep soils on marly-calcareous and thus carbonate- rich parent rocks of the Upper Cretaceous, which - with comparable subsoil - can often be found in the vicinity of the rendzines treated in the previous section. They consist of clayey loam with limestone fragments embedded. Silt components are also often found in the topsoil. Typical is the high content of embedded stones up to the surface, so that the soil remains permeable to water despite its weight. The weathering of the limestone bricks stands in the way of acidification; the pH value is always above the 5.5 mark.
Despite the high proportion of clay and loam, the brown earth soils are ideally suited for agricultural use, especially for growing grain, due to the lime components. As a natural vegetation, deciduous forest, especially pearl grass - beech forest , is typical.
  • Low-base brown earth soils
The silicate-rich rocks of the Lower Cretaceous form the starting material for another, base-poor type of brown earth. Shallow to medium-deep brown soils with a low base of bases can be found along the Osning sandstone in the ridges of the Teutoburg Forest ; further down, the thickness of this ground cover increases. A sand content of more than 85% ensures high air and water permeability. The low base content and the rapid removal of nutrients into deeper layers favor a podsolization (bleaching) of the topsoil. It can be assumed that locally available podsols arose from brown earth. The brown soils of the Osnings and their transition types are predominantly forested. They are not suitable for agricultural use.
In addition, brown earths with poor bases, originating from the Old Pleistocene and therefore old, can also be found in Westmünsterland on the main Rhine terrace, for example in a strip from Borken to Duisburg . They are partially interspersed with iron-bearing horizons that formed in the oxidation zone in the area of ​​the groundwater level during the interglacial warm periods. Transition types to podsol are widespread. The soils are low-yield and are often used for forestry.
  • Parabrown earths
Parabroun earths formed primarily on loess and sand loess , which was blown by the wind during the last glacial period . This happened over a large area in the south of the Westphalian Bay in an area from the Hellwegbörden via the Westenhellweg to the Soester Börde . A characteristic of parabrown soils is that clay and silt components have been mechanically shifted from the topsoil to the subsoil with the seepage water . The deep soils are among the most fertile of all. Due to the clay enrichment in the subsoil, they are largely immune to drying out.
  • Podsole
Podsols are impoverished soils that lack clay minerals . They formed on quartz-rich substrates , i.e. in the Münsterland on the sediments of the Upper Cretaceous, but also on sands of various origins. You can find them in large areas in the West but also in the Kernmünsterland, z. B. on the Haltern Sands and the low terraces and valley sand plains of the Münsterland. In part, especially in heather areas, a vegetation- inhibiting and water-impermeable layer of local stone has formed in the subsoil.
  • Pseudogley
Typical pseudogley on the Coesfeld mountain.
Pseudogley is a heavy, poorly ventilated backwater bottom with a horizon that is difficult to penetrate into the subsoil . Pseudogleye are particularly problematic in spring, when the soil is saturated with water at the end of the winter half-year due to high rainfall and little evaporation. In the summer months, however, there are regular signs of dehydration.
In the Münsterland, pseudogleye can be found in large areas of the plains above the clayey ground moraine , as well as in the flat heights of the tree mountains over clayey rock of the Upper Cretaceous. They can also be found at the transition to the Lower Rhine Plain, here above tertiary clays. They are primarily used as grassland, but also for forestry (mainly English oak and pure beech forests). Pseudogleye gain in quality if they are covered by a sandy top layer of meltwater or drift sand; the waterlogging is then only noticeable in the sub-floor. In the topsoil then run Podsolierungsprozesse from. A prerequisite for the agricultural use of these soils is drainage, which is often difficult given the flat terrain.
  • Gley floors
Gleye differ from the pseudogleyen in that their formation is not based on waterlogging, but on a comparatively stable groundwater level in the soil. Most of the year the water level is about forty to eighty centimeters below the ground. Gley bottoms are thus in the young stream valleys as well as the low terraces and valley sand locations in relative proximity to the river, where they take the space between the floodplain and the only slightly higher podzols. In part, horizons made of iron stone were precipitated in the oxidation area of ​​the groundwater table. The topsoil consists of fine and medium-fine sands that contain silty components and merge into coarser sand at depth.
  • Floodplain soils
Alluvial grounds accompany the two largest rivers in the Münsterland, the Ems and Lippe . They are of Holocene origin and are characterized by a high, strongly fluctuating groundwater level, which depends on the flow of water in the rivers. They are also regularly flooded during floods. As a result, they are flat and on both sides of the river bed in strips of different widths. The soil of the Münsterland floodplain soil consists of fluvial sands with different levels of clay, which is often gravelly in the subsoil. They are mostly used as pastureland, and in relatively high areas as arable land.
  • Fens, peat soils
In the low-lying areas with relatively lower elevations, mainly along rivers where the groundwater reaches to the surface of the earth, fens with peat soils have developed, the proportion of organic matter, decomposed peat over sand, silt and clay, often exceeding 40%. In the Münsterland you can find them z. B. along the Heubach near Maria Veen and Hausdülmen , in the Merfelder Bruch , west of Rhade and in small areas in river valleys and oxbow channels. Generally they are used as grassland, rarely as grazing land. Some of them have been changed through soil improvement measures and drainage.
  • Raised bogs
In the Burlo-Vardingholter Venn , the raised bog has been regenerating since the rewetting measures were completed
Raised moors can be found in the Münsterland along today's state border with the Netherlands (including Burlo-Vardingholter Venn , Zwillbrocker Venn and Amtsvenn ), in the Velen  / Coesfeld area ( Black and White Venn ), and in the Tecklenburger Land ( Recker Moor , Koffituten ). High moor soils developed predominantly over the water- retaining ground moraine. Their time of origin goes back to the Atlantic . The peat soils consist of mighty peat horizons up to several meters thick, which have formed from undemanding peat mosses in a nutrient-poor, low-oxygen, acidic environment . These mosses grow in water-saturated cushions beyond their own environment.
The upland moors in the Münsterland are now mostly pitted and cultivated. The few remaining remains were placed under protection . In the last few decades, rewetting and renaturation measures have been carried out or initiated in order to preserve the few intact raised bog populations for posterity. An example of this is the Schwatt Gatt in Vreden . Only small remnants of the White Fens remain in the area of ​​the Fürstenkuhle, close to their original state. The peat museum in Hochmoor gives an overview of the reclamation of this formerly largest contiguous moor area in the Münsterland.
  • Plaggenesch
The Plaggeneschen of the sandy Westmünsterland are soils that have developed through pest fertilization . Grass or heather was plagued with manure, ash and biological waste after composting on the mostly podsolic base in order to improve the quality of the light soils. Due to the discharge that took place over many centuries, the so-called ash trees are now often slightly higher than the surrounding area. Since the advent of mineral fertilizers at the beginning of the 20th century, labor-intensive and time-consuming pest fertilization is no longer practiced. The soil type is basically on the decline. Larger areas can be found between Borken and Stadtlohn , between Lette and Dülmen , in the area of ​​the gravel sand stretch south of Münster and at the foot of the Teutoburg Forest . In addition, isolated Hofesche can be found all over the Münsterland. The Plaggenesche are now relatively easy to work with and also well suited for growing demanding crops.

Fossils

Ammonite (Pachydiscus) from the upper Campan of the Coesfelder Berg , Ø 23 cm
Fossil sponge, reading discovery (near Rosendahl-Holtwick, Oct. 2015) near the B474 known as the "Street of the Sea Urchins".

The oldest report on fossil finds in the Münsterland dates from around 1550. At that time, the Münster sculptor Frantz Brabender wandered over villages and fairs with the imprint of a fossilized fish in the sandstone. In Kampen, the Netherlands, he was accused of fraud and was about to be arrested. On his escape, he first had to leave the fish behind and then wrote a letter of complaint to the City of Munster. It was only through the successful mediation efforts of Countess Walburga zu Bentheim that the fish got back to Germany. It has been kept in Bentheim Castle since then , but was lost in the turmoil of the final days of the war in 1945.

Fish skeletons of the Baumberger layers occur mainly in the joint called Hoetmar , which is embedded between the upper and lower flow of the work stone bench. Remains of warm water-loving organisms, including corals, ammonites , belemnites and sea ​​urchins, have also been found as fossils from the Cretaceous period . The largest ammonite in the world, Parapuzosia seppenradensis , comes from a quarry near Seppenrade and is now on display in the LWL Museum of Natural History . The B 474 from Coesfeld via Holtwick and Legden to Ahaus has become known in specialist literature as the street of the sea urchins because of the numerous aboveground reading finds on its sides .

Numerous fossils are also known from the Quaternary large mammals. A completely preserved skeleton of a woolly mammoth was found in a clay pit near Ahlen in 1910. Today it is part of the collection of the Geological-Paleontological Museum in Münster . In addition to mammoth bones and tusks, remains of cave bears , bison and aurochs have also been found in the ice age river sands .

Natural resources

Stones and earth

Sandstone, lime

Sandstone been used for centuries in the tree mountains , in Ibbenbürener space and in Bad Bentheim , the natural area still belongs to Westmünsterland, mined and processed. Many well-known and unknown buildings in the region, including the Paulus and Ludgerus Cathedral in Münster and Billerbeck , were built from Baumberger sand-lime brick , which is still quarried in three quarries on the Westerberg . The Baumberger Sandstone Museum in Havixbeck is devoting an exhibition to this relatively soft and weather-prone building and stone , which was exported to Sweden and the Baltic States in the Middle Ages. In the Ibbenbüren be cretaceous Liche Osning sandstone and carbon- time Ibbenbürener sandstone broken. Both are more resistant to weathering than Baumberger sandstone. The Ibbenbürener sandstone is mined on the Schafberg in the northern district of Steinfurt (one of the four so-called "Münsterlandkreise"); However, the Schafberg is located north of the Teutoburg Forest in the Osnabrück hill country and, strictly speaking, does not belong to the geological unit considered here. Another solid, weather-resistant and hard sandstone is the Bentheimer and Gildehauser sandstone , which is found in the northwest of the Westphalian Bay in Lower Saxony.

The Beckum Mountains are also made of limestone . Lime was burned in simple field ovens between Beckum and Ennigerloh as early as the Middle Ages . The Beckum cement district was established there in close proximity to the Ruhr area at the end of the 19th century . With 32 cement works, it was considered the largest of its kind in the world in 1930. At its peak, 3.7 million tons of cement were produced in 1961 during the reconstruction period after the Second World War . The structural crisis in the Ruhr area did not leave the Beckum works without a trace. Production was cut back and numerous medium-sized companies were sold to large stock corporations. Formerly more than 2000 employees in the Beckum cement industry are compared to around 500 today. In the Beckum region, cement clinker is now only produced in three plants.

Sand and gravel

In the Münsterland there are numerous deposits of sand and gravel , most of which are used in the local construction industry. These raw materials are mainly of Cretaceous or Quaternary origin. The mining areas are often below the groundwater level, so that large quarry ponds such as the silver ponds between Haltern and Hausdülmen have emerged. The Haltern strata , which make up more than half of the entire North Rhine-Westphalian quartz sand production, are tapped here . Above-ground extraction is more likely in the higher central terraces or on the threshold of the bordering low mountain ranges. In the west of the Münsterland, in the transition to the Lower Rhine lowlands, Tertiary sediments (e.g. Walsum layers) and the main Rhine terraces are also used to extract gravel and sand. In the northern and eastern Münsterland, the sands - there are practically no gravel deposits here - can be traced back to Quaternary river deposits and meltwater. Around 5% of the sand production is made up of high-quality special sands with a silicon dioxide content of 97% to over 99%.

Clay and clay marl stones

The clay and clay marl stones from the chalk, which are widespread in the Münsterland, as well as the tertiary clay stones found in the transition to the Lower Rhine (e.g. Emscher marl ) are used in the manufacture of bricks . The focus of production was the Westmünsterland, the Coesfelder and the Lüdinghauser area. However, quite a few of the brickworks have now been closed.

Strontianite occurrence

Strontianite from the "Mathilde" pit near Ascheberg (sample size 9 cm × 6 cm)

In 1834 a farmer near Nienberge discovered a hitherto little-known mineral - strontianite (SrCO 3 , strontium carbonate). In 1839/40 it was also found between Hamm and Drensteinfurt . Due to their purity, the Münsterland deposits of around 150,000 tons are considered to be the most important raw material deposits of this mineral worldwide. In the early years it was not systematically dismantled, but only sold in small quantities to pharmacists and fireworkers. After a Saxon sugar factory in Dessau extracted the residual sugar from the molasses with the help of strontianite in 1871 , there was an industrial need for the mineral. As a result, around 700 pits were created in which up to 2200 miners were employed. The center of the promotion was between Ascheberg in the west, Ahlen in the east, Drensteinfurt in the north and Hamm in the south. The deepest shaft of the Alwine mine in Vorhelm led 110 meters underground. The boom subsided as early as 1883 after strontianite and celestine (SrCO 4 ) became cheaper competitors. In January 1945, industrial dismantling was finally stopped when the last mine in Ascheberg closed its doors.

Rock salt deposits and brine extraction

Graduation tower in Bad Rothenfelde

Around 250 million years ago, rock salt up to 400 meters thick was deposited in a lagoon that stretched as the marginal sea of ​​the northern German Zechstein basin from Gronau in the north along the German-Dutch border to the Moers area . Their average thickness is around 200 to 250 meters. The surface of the salt store is about 300 meters below the ground in the south, at Bocholt it is already 1500 meters. The salt is of great purity. It is extracted in the Borth salt mine on the Lower Rhine in the chamber construction and also sold as table salt . At Epe , large underground caverns are extracted in the rock salt, which serve as natural gas and oil deposits. Around 3.5 billion m³ of gas can be stored in the around 100 gas caverns and around 1.4 million m³ of the national oil reserve in the three oil caverns . As part of the Sculpture Biennale Münsterland 2005 between Gronau and Bocholt, the artist Franz John created a work of art made up of eight rod fields connected by a cycle path, which is intended to raise public awareness of the salt stores in western Münsterland.

Salt has been produced on the mountainous edges of the Westphalian Bay for centuries, initially from natural brine . The composition of the Munsterland brine has likely remained largely unchanged for around 60 million years. Its history goes back to the subsidence processes in the Cenoman , during which the sea advanced into today's Ruhr area. The salt water contained in the sediments of this sea seeped into the mountains below and thus laid the foundation for today's brine deposits. Salt production is the oldest branch of industry in Westphalia . Archaeological finds have shown that Werl was already mining salt 700 years before the birth of Christ. Well-known production facilities were z. B. Unna ( Saline Königsborn ) and Bad Sassendorf , Bad Waldliesborn and Bad Westernkotten and Bad Laer and Bad Rothenfelde in the Teutoburg Forest . The former saline Gottesgabe near Rheine extracted its brine from the Röt - saline of the Salzbergener saddle , which geologically is no longer included in the Münsterland chalk basin.

mineral oil and natural gas

Various deep boreholes, which were also used to explore mineral resources, play a major role in today's knowledge of the geology of the Münsterland . Natural gas leaks from earlier exploratory drillings on coal were known in the Ascheberg - Lüdinghausen area. The natural asphalt leaks known from the Darfeld area also suggested that there might be oil deposits below. However, the plan was not to look for hydrocarbon deposits until the late 1930s. During these years, boreholes were carried out at Ascheberg, Oelde, Hiltrup, Senden / Appelhülsen and Seppenrade, which indeed gave indications of corresponding occurrences, but found no actual deposits.

Of all the boreholes , the Münsterland 1 borehole , which was carried out in the Baumberge Mountains in 1961/62 and was the deepest borehole in Europe at the time , stands out. It was carried out from July 10, 1961 to December 5, 1962 in Aulendorf, which belongs to Billerbeck, as a chisel drilling , in which drill cores , a total of 318 meters, were taken only in layers that appeared to be worthwhile . The location was chosen because it was assumed that the overlying hard coal overburden was relatively thin. The borehole reached a depth of 5956 meters, where it penetrated rocks from the Middle Devonian. To this day, it has remained the deepest exploration in North Rhine-Westphalia . At the lowest point the temperature was around 200 ° C. The borehole had a diameter of 45 cm. Up to the point of drilling, only the layers up to a depth of 2,400 meters were known. With the drilling, the underlying rocks were explored in particular for crude oil and natural gas. However, the strata drilled did not fulfill hopes; As a result of the advanced diagenesis , exploitation of oil and gas was out of the question at the time. The results of the Münsterland 1 borehole also included the determination of the sedimentation speed. The layer growth near the surface was around 11 to 12 cm per 1000 years at the drilling point on Billerbecker Berg. The cost of the drilling was around DM 9 million, which the state of North Rhine-Westphalia shared with a consortium of eight exploration companies.

The Versmold 1 and Isselburg 3 exploratory wells also penetrated the subsurface at depths of around 5500 and 4400 meters, respectively. However, they also showed no signs of profitable oil and gas deposits. The first indications of this did not come from boreholes near Ochtrup until 1990 . Here gas deposits were found in the Upper Carboniferous layers under a sealing Zechstein salt deposit.

Fracking plans in the Münsterland

Today it is assumed that there are huge natural gas deposits in the underground of the Münsterland. The conversion of peat to anthracite produces an estimated 200 m³ of methane per tonne of coal, which is absorbed as seam gas and in the fissured rock. With a new type of conveying technology, hydraulic fracturing , which became known as fracking , these could be made usable. A liquid mixed with chemicals is pressed under high pressure into the rock to break it up so that the gas can flow to the drilling site. However, the method is highly controversial due to the risks to groundwater. The exploration company ExxonMobil planned test boreholes in Borkenwirthe near Borken , Nordwalde and Drensteinfurt . As a result, various “ citizens' initiatives against gas drilling” have been formed, which, in close coordination with one another, organize the resistance against the planned fracking in the Münsterland. The state government of North Rhine-Westphalia has currently imposed a moratorium on fracking. Due to the strong dependency on Russian gas supplies, this moratorium is currently (2014) being questioned by some leading politicians, especially the CDU , and experts from the BDI . In connection with the Crimean crisis, for example, Oliver Wittke and the German EU Commissioner for Energy Günther Oettinger called for fracking not to be rejected in principle and the option of shale gas extraction not to be prematurely given up. With fracking one can make oneself largely independent of Russian natural gas deliveries, because the own share in the German natural gas market could be increased from currently around 10% to 35% by 2030.

Hard coal

Coal mining in the Ruhr mining industry in the 19th century

Far to the north of the viewing area in Ibbenbüren , and in the south, in the Ruhr region , is coal promoted. In between, the seam-bearing layers sink to great depths so that mining is not an option here. In these undeveloped areas of the Münsterland, 180 billion tons of coal are suspected, which is many times more than the 9 billion tons extracted in the Ruhr mining industry until 1994.

In the past, mining in the Ruhr stretched over a stretch of more than 100 kilometers from the left Lower Rhine along the Emscher and Ruhr to Ahlen in the southern Warendorf district . On the slopes south of the Ruhr, where the seams reach the surface of the earth, coal was mined in Pingen centuries ago . Tunnel mines were later operated there, which in the course of industrialization at the beginning of the 19th century were increasingly replaced by underground mines where the groundwater had to be pumped out. In the course of time the coal mining migrated north to the Lippe . The last two mines operated by RAG Deutsche Steinkohle AG were the Ibbenbüren and Prosper-Haniel mines in Bottrop . They were closed in December 2018 as the last German hard coal production facilities. Caused by the Ruhr mining and anticipated mining damage represents a serious problem. The RAG are reported annually around 35,000 new cases each with a value of 300 million euros. The costs for regulating the groundwater amount to around 100 million euros per year.

Ores

In addition to hard coal, iron spades are stored in the rocks of the Carboniferous period, often in the immediate vicinity of the seams . These go back to bog waters in which the decomposition of organic material released iron carbonate solutions from which the ore was precipitated. These ore deposits formed the basis of the iron and steel industry in the Ruhr area , which produced well-known companies such as Thyssen AG , Hoesch AG and Friedrich Krupp AG , which have now merged to form ThyssenKrupp AG . In addition, lawn iron stones that formed near the surface in the oxidation area of ​​the groundwater level in the relative vicinity of the river were smelted. The St. Antony-Hütte in Oberhausen - Osterfeld , which later became part of the Gutehoffnungshütte, started operations in 1758 as the first ironworks in the Ruhr area and made use of the on-site iron slab deposits. The St. Michaelis ironworks in Liedern near Bocholt , which also used iron slab deposits, had already been opened in 1729; It was closed in 1862. There are other important lawn iron stone sites in the Marl area and near Holte Castle in the Senne .

Between 1936 and 1968, lead , zinc and silver ores were also mined in the Ruhr area , the occurrence of which is concentrated at the interfaces of steep faults with the Upper Carboniferous overburden saddles. Today it is believed that these ores were precipitated in the rise of hot solutions that came from older layers of the Paleozoic Era . The ore from the Auguste Victoria colliery in Marl contained 7% zinc, 3.9% lead and 65 g silver per ton, while that from the Christian Levin colliery in Essen contained 10.7% lead, 0.5% zinc and 26 g silver per ton. These two mines produced a total of around 5.4 million tons of ore. Other ore deposits of around 5 million tons in the Auguste Victoria and Graf Moltke collieries in Gladbeck , which were not mined, are known.

Geological outcrops

Natural geological outcrops of the rock below are comparatively rare in the interior of the Westphalian Bay. In the generally quite flat landscape with little relief, the layers of geological interest are usually hidden under Holocene deposits and covered by vegetation. The situation is different in the foothills. The steeply tilted Osning sandstone forms the backbone of the Teutoburg Forest and emerges in many places. Well-known rock formations made of Osning sandstone are the Externsteine near Horn-Bad Meinberg and the Dörenther cliffs with the crouching woman south of Ibbenbüren.

Quarries are also suitable for insights into the Cretaceous rocks . B. in the Baumberge am Westerberg , the Beckum mountains and on the slopes of the Teutoburg Forest sandstone is broken. Quarries in which work and building blocks are still actively being mined are usually not free, but rather accessible as part of guided tours.

In the following, some special geological outcrops are also listed that make the development of geology in the Münsterland tangible.

  • In the Geological Garden in Bochum you can see how Cretaceous rocks lie directly on the tipped deposits of carbon. There are no sediments from the intervening epochs of Permian, Jurassic and Triassic.
  • In the geotope Jammertal near Hörsteloe near Ahaus, there is a ground exposure that shows the development of the landscape over an exceptionally long period of time. Around 130 million years of geological history are spread here. The present band parabraunerde podsol is a very rare type of soil on Gildehaus sandstone . This sandstone was created by the weathering of the Cretaceous sands during the Tertiary under subtropical to tropical climatic conditions. Iron rind horizons run through the ground above the solidified sandstone. The soil near the surface is very acidic and poor in nutrients.
  • On the Hünsberg southwest of Coesfeld there are several outcrops of Halterner Sands . In these layers have the fossil Gley during Tertiary of the former ground water level in the (sub) tropical climate at the level of partly skurril shaped limonit ical iron slabs formed, which were exposed in the intermediate glacial by the wind and ground.
  • The Ölbach near Ahaus forms a special natural outcrop, which has dug itself into the layers of the Alb (Lower Cretaceous) in the upper and middle reaches and exposes numerous fossils, especially belemnites .
  • The former Weiner Esch quarry near Ochtrup is also known for its wealth of fossils. Among them are belemnites and mollusks , shark and ray teeth.

literature

Web links

See also

Individual evidence

  1. ↑ a b The Münsterland 1. borehole (PDF) (No longer available online.) Geological Survey North Rhine-Westphalia , archived from the original on March 24, 2014 ; Retrieved December 27, 2013 . 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. @1@ 2Template: Webachiv / IABot / www.museum-zurholt.de
  2. ↑ Geological overview. (PDF) (No longer available online.) Geological Survey North Rhine-Westphalia , archived from the original on March 24, 2014 ; Retrieved December 27, 2013 . 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. @1@ 2Template: Webachiv / IABot / www.museum-zurholt.de
  3. ↑ a b Borehole Münsterland 1 on the website of the Mineral and Fossil Museum Zurholt in Altenberge .
  4. ^ Geological geological ages on the website of the Mineral and Fossil Museum Zurholt in Altenberge .
  5. ^ Heinz Heineberg , Klaus Temlitz (ed.): The district of Coesfeld (=  cities and municipalities in Westphalia . Volume 7 ). 1st edition. Ardey-Verlag , Münster 2000, ISBN 3-87023-101-7 , p. 6 .
  6. ↑ a b Geological Service North Rhine-Westphalia (ed.): Geology in the Münsterland . 1st edition. Krefeld 1995, ISBN 3-86029-922-0 , p. 132 f . ( online [PDF; accessed December 30, 2013] special publication). Geology in Münsterland ( Memento of the original from March 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 the instructions and then remove this notice.  @1@ 2Template: Webachiv / IABot / www.gd.nrw.de
  7. ↑ Klaus Temlitz: Westphalia in the underground: Tectonic building units. (url) Westphalian Oberkreidemulde (Münsterland, Hellweg area). Landschaftsverband Westfalen-Lippe , accessed on December 28, 2013 .
  8. ↑ Jörg Mutterlose, Adrian Immenhauser: Climate change in the history of the earth: the Cretaceous period was a greenhouse world. RUBY. Special Geosciences Edition, 2007, pp. 6–12 ( PDF ( Memento from June 11, 2007 in the Internet Archive )) 750 kB
  9. ↑ The Cretaceous Period - Transition from the Mainland to the Sea. (PDF) (No longer available online.) Geological Survey North Rhine-Westphalia , archived from the original on March 23, 2014 ; Retrieved December 27, 2013 . 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. @1@ 2Template: Webachiv / IABot / www.museum-zurholt.de
  10. ↑ a b c d Regional engineering geology. (PDF) (No longer available online.) TU Bergakademie Freiberg, p. 138 , archived from the original on December 6, 2012 ; accessed on March 15, 2014 (course). 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. @1@ 2Template: Webachiv / IABot / tu-freiberg.de
  11. ↑ Knowledge about quartz sand ( Memento of the original dated December 2, 2013 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. , at www.euroquarz.de @1@ 2Template: Webachiv / IABot / www.euroquarz.de
  12. ^ Hydrogeological advice - Münster district. (url) (No longer available online.) Geological Survey North Rhine-Westphalia , archived from the original on March 24, 2014 ; Retrieved December 29, 2013 . 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. @1@ 2Template: Webachiv / IABot / www.gd.nrw.de
  13. ↑ Cretaceous Period (145 - 65 million years) on the website of the Mineral and Fossil Museum Zurholt in Altenberge .
  14. ^ Heinz Heineberg, Klaus Temlitz (ed.): The district of Coesfeld (=  cities and municipalities in Westphalia . Volume 7 ). 1st edition. Ardey-Verlag , Münster 2000, ISBN 3-87023-101-7 , p. 8 .
  15. ^ Geological Service North Rhine-Westphalia (Ed.): Geology in the Münsterland . 1st edition. Krefeld 1995, ISBN 3-86029-922-0 , p. 142) ( online [PDF; accessed December 30, 2013] special publication). Geology in Münsterland ( Memento of the original from March 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 the instructions and then remove this notice.  @1@ 2Template: Webachiv / IABot / www.gd.nrw.de
  16. ^ A b c Geological Service North Rhine-Westphalia (Ed.): Geology in the Münsterland . 1st edition. Krefeld 1995, ISBN 3-86029-922-0 , p. 69, 113 ( online [PDF; accessed December 30, 2013] special publication). Geology in Münsterland ( Memento of the original from March 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 the instructions and then remove this notice.  @1@ 2Template: Webachiv / IABot / www.gd.nrw.de
  17. ↑ a b c Helmut Bechtel: The Münsterland in color. Colorful Kosmos pocket guide, Kosmos Society of Friends of Nature, Franckh'sche Verlagsbuchhandlung, Stuttgart 1978, p. 62.
  18. ^ A b Heinz Heineberg, Klaus Temlitz (ed.): The district of Coesfeld (=  cities and municipalities in Westphalia . Volume 7 ). 1st edition. Ardey-Verlag , Münster 2000, ISBN 3-87023-101-7 , p. 9 .
  19. ↑ The Quaternary Age of Glaciers. (PDF) (No longer available online.) Geological Survey North Rhine-Westphalia , archived from the original on March 24, 2014 ; Retrieved December 27, 2013 . 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. @1@ 2Template: Webachiv / IABot / www.museum-zurholt.de
  20. ↑ Geology in the Münsterland. (PDF) Preview of 2 publications. Geological State Office of North Rhine-Westphalia, Krefeld, p. 4 , accessed on December 29, 2013 .
  21. ↑ Karl-Heinz Otto: How the foundlings came to Westphalia! on the website of the Regional Association of Westphalia-Lippe
  22. ^ Geological Service North Rhine-Westphalia (Ed.): Geology in the Münsterland . 1st edition. Krefeld 1995, ISBN 3-86029-922-0 , p. 144 ( online [PDF; accessed December 30, 2013] special publication). Geology in Münsterland ( Memento of the original from March 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 the instructions and then remove this notice.  @1@ 2Template: Webachiv / IABot / www.gd.nrw.de
  23. ↑ Geology in the Münsterland. (PDF) Preview of 2 publications. Geological State Office of North Rhine-Westphalia, Krefeld, p. 8 , accessed on December 29, 2013 .
  24. ↑ Geology in the Münsterland. (PDF) Preview of 2 publications. Geological State Office of North Rhine-Westphalia, Krefeld, p. 114 , accessed on December 29, 2013 .
  25. ↑ Geology in the Münsterland. (PDF) Preview of 2 publications. Geological State Office of North Rhine-Westphalia, Krefeld, p. 79 , accessed on December 29, 2013 .
  26. ^ Herbert Liedtke: Westphalia in the Ice Age. (url) Landschaftsverband Westfalen-Lippe , accessed on December 29, 2013 .
  27. ^ Geological Service North Rhine-Westphalia (Ed.): Geology in the Münsterland . 1st edition. Krefeld 1995, ISBN 3-86029-922-0 , p. 106 - 117 ( online [PDF; accessed December 30, 2013] special publication). Geology in Münsterland ( Memento of the original from March 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 the instructions and then remove this notice.  @1@ 2Template: Webachiv / IABot / www.gd.nrw.de
  28. ↑ Information on the peat museum Hochmoor on the website of the city of Gescher
  29. ↑ The Baumberg region. (PDF; 11.7 MB) On the trail of nature. Baumberge Touristik , an association of the cities and communities Billerbeck , Coesfeld , Havixbeck , Nottuln and Rosendahl , February 24, 2014, p. 7 , accessed on February 24, 2014 .
  30. ↑ Barbara Alberts, Martin Hiss: Geological monuments in the Münsterland. (PDF) (No longer available online.) In: Spieker, Regional Studies Contributions and Reports No. 36 - Münsterland and neighboring regions . Landschaftsverband Westfalen-Lippe , 1993, p. 6 , archived from the original on January 7, 2014 ; accessed on February 24, 2014 . 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. @1@ 2Template: Webachiv / IABot / www.lwl.org
  31. ↑ a b Lioba Beyer: The tree mountains . Ed .: Geographical regional studies department of the Westphalian Heimatbund (=  Landscape Guide of the Westphalian Heimatbund . Volume 8 ). Aschendorff, Münster 1975, p. 59 f .
  32. ↑ Museum Zurholt. (PDF) (No longer available online.) Formerly in the original ; Retrieved December 28, 2013 (Flyer of the Fossils and Minerals Museum).  ( Page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.@1@ 2Template: Toter Link / www.museum-zurholt.de  
  33. ↑ The Baumberg region. (PDF; 11.7 MB) On the trail of nature. Baumberge Touristik , an association of the cities and communities Billerbeck , Coesfeld , Havixbeck , Nottuln and Rosendahl , February 24, 2014, p. 47 (p. 15 of 64) , accessed on February 24, 2014 .
  34. ^ Geological Service North Rhine-Westphalia (Ed.): Geology in the Münsterland . 1st edition. Krefeld 1995, ISBN 3-86029-922-0 , p. 147 ( online [PDF; accessed December 30, 2013] special publication). Geology in Münsterland ( Memento of the original from March 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 the instructions and then remove this notice.  @1@ 2Template: Webachiv / IABot / www.gd.nrw.de
  35. ^ Olaf Otto Dillmann, qualified geologist: Baumberger Kalksandstein
  36. ^ History of the Beckum cement industry on the website of the Beckum cement museum .
  37. ↑ a b Strontianite mining in Ottmarsbocholt (1883–1919)
  38. ^ Geological Service North Rhine-Westphalia (Ed.): Geology in the Münsterland . 1st edition. Krefeld 1995, ISBN 3-86029-922-0 , p. 138 f . ( online [PDF; accessed December 30, 2013] special publication). Geology in Münsterland ( Memento of the original from March 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 the instructions and then remove this notice.  @1@ 2Template: Webachiv / IABot / www.gd.nrw.de
  39. ^ Geological Service North Rhine-Westphalia (Ed.): Geology in the Münsterland . 1st edition. Krefeld 1995, ISBN 3-86029-922-0 , p. 139 ( online [PDF; accessed December 30, 2013] special publication). Geology in Münsterland ( Memento of the original from March 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 the instructions and then remove this notice.  @1@ 2Template: Webachiv / IABot / www.gd.nrw.de
  40. ^ Manfred Dölling, Andreas Lenz: Strontianite mining in the Drensteinfurt area (Münsterland) - a largely forgotten mining heritage harbors current geo-risks. (PDF) Geological Service North Rhine-Westphalia , accessed on March 2, 2014 ((Preview)).
  41. ^ Martin Börnchen: The Strontianite mining in the Münsterland. (PDF) Landschaftsverband Westfalen-Lippe , accessed on March 2, 2014 .
  42. ↑ Geological Survey North Rhine-Westphalia : Franz John - The Salztangente ( Memento of the original from April 19, 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 the instructions and then remove this notice. , an art project on "white gold" in the Münsterland @1@ 2Template: Webachiv / IABot / www.gd.nrw.de
  43. ↑ Westfälische Nachrichten of April 14, 2014: Background - Oil storage in salt caverns
  44. ↑ Franz John: The salt tangent .
  45. ^ Geological Service North Rhine-Westphalia (Ed.): Geology in the Münsterland . 1st edition. Krefeld 1995, ISBN 3-86029-922-0 , p. 120 ff . ( online [PDF; accessed December 30, 2013] special publication). Geology in Münsterland ( Memento of the original from March 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 the instructions and then remove this notice.  @1@ 2Template: Webachiv / IABot / www.gd.nrw.de
  46. ^ Geological Service North Rhine-Westphalia (Ed.): Geology in the Münsterland . 1st edition. Krefeld 1995, ISBN 3-86029-922-0 , p. 124 ( online [PDF; accessed December 30, 2013] special publication). Geology in Münsterland ( Memento of the original from March 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 the instructions and then remove this notice.  @1@ 2Template: Webachiv / IABot / www.gd.nrw.de
  47. ↑ a b c d Geological Service North Rhine-Westphalia (ed.): Geology in the Münsterland . 1st edition. Krefeld 1995, ISBN 3-86029-922-0 , p. 136 ( online [PDF; accessed February 25, 2014] special publication). Geology in Münsterland ( Memento of the original from March 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 the instructions and then remove this notice.  @1@ 2Template: Webachiv / IABot / www.gd.nrw.de
  48. ↑ Cf. Gegen Gasbohren… - Association of Initiatives against Uncontrolled Natural Gas Search and Hydraulic "Fracking" Fracturing in Germany.
  49. ↑ # 93; = 225679 Gabot.de ( memento of the original from September 24, 2015 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.gabot.de
  50. ↑ Die Welt of March 29, 2014: The fracking debate flares up again in North Rhine-Westphalia
  51. ↑ Handelsblatt title story (print edition) from March 31, 2014.
  52. ^ Geological Service North Rhine-Westphalia (Ed.): Geology in the Münsterland . 1st edition. Krefeld 1995, ISBN 3-86029-922-0 , p. 130 ( online [PDF; accessed December 30, 2013] special publication). Geology in Münsterland ( Memento of the original from March 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 the instructions and then remove this notice.  @1@ 2Template: Webachiv / IABot / www.gd.nrw.de
  53. ↑ Aachener Nachrichten of December 4, 2018: Ibbenbürener miners present “last coal” to Laschet
  54. ↑ Trouble with mountain damage - This is how the coal company RAG reacts , Der Westen from May 24, 2013.
  55. ^ Joachim Juergens: Mining & mining damage, the contaminated sites. (PDF) (No longer available online.) December 16, 2011, p. 15 , archived from the original on March 24, 2014 ; accessed on March 16, 2014 . 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. @1@ 2Template: Webachiv / IABot / archiv.pro-herten.de
  56. ^ Manfred Rasch, Dieter Bleidick, Wolfhard Weber: History of technology in the Ruhr area. Technical history for the Ruhr area . Klartext Verlag, 2004, p. 562
  57. ↑ Klara van Eyll (ed.), Renate Schwärzel (arrangement): Deutsche Wirtschafts-Archive , Volume 1 , Franz Steiner Verlag, Stuttgart 1994, ISBN 3-515-06211-4 , p. 266
  58. ↑ a b Geological Service North Rhine-Westphalia (ed.): Geology in the Münsterland . 1st edition. Krefeld 1995, ISBN 3-86029-922-0 , p. 133 f . ( online [PDF; accessed December 30, 2013] special publication). Geology in Münsterland ( Memento of the original from March 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 the instructions and then remove this notice.  @1@ 2Template: Webachiv / IABot / www.gd.nrw.de
  59. ↑ See Steinreich.  ( Page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. at: baumberge.com@1@ 2Template: Dead Link / www.baumberge.com  
  60. ^ Geological Service North Rhine-Westphalia (Ed.): Geotopes in North Rhine-Westphalia . Evidence of the history of the earth. 3rd, revised edition. Krefeld 2008, ISBN 978-3-86029-972-2 , Landschaftsarchiv im Münsterland, p. 38 .
  61. ↑ a b c Helmut Bechtel: The Münsterland in Color , Bunte Kosmos Pocket Guide, Kosmos Society of Friends of Nature, Franckh'sche Verlagsbuchhandlung, Stuttgart 1978, p. 62.