Paffrather limestone basin

Paffrather Kalkmulde ; Paffrather Kalkmulde
	The Paffrather Kalkmulde according to Ulrich Jux : At the northwesternmost point was the Romeo mine , to the northeast the Luther mine with the Katharinaglück operating point and the Consolidierte Catharina II mine to the south .
Systematics according to	Handbook of the natural spatial structure of Germany
Greater region 1st order	Low mountain range threshold
Greater region 2nd order	Rhenish Slate Mountains
Main unit group	33 → ; Süderbergland
About main unit	338 → ; Bergische plateaus
4th order region ; (main unit)	338.2 → ; Südbergische Plateau
Natural space	338.23 → ; Paffrather Kalkmulde ; Paffrather Kalkmulde
	Geographical location
Coordinates	50 ° 59 '48 " N , 7 ° 9' 24" E Coordinates: 50 ° 59 '48 " N , 7 ° 9' 24" E
	Location Paffrather Kalkmulde ; Paffrather Kalkmulde
local community	Bergisch Gladbach , Kürten , Odenthal
state	North Rhine-Westphalia
Country	Germany

The Paffrather Kalkmulde also Bergisch Gladbach-Paffrather trough , Gladbach-Paffrather trough , Gladbach-Paffrather Kalkmulde or Paffrather Kalksenke called, is a geological well structure , which to a large extent on the urban area of Bergisch Gladbach located.

According to the handbook of the natural spatial structure of Germany, it is a natural spatial unit with the order number 338.23 and belongs to the Südbergische plateau (338.2) within the Bergische plateau (338). The Mulde is named after the Bergisch Gladbach district of Paffrath .

description

The Paffrather Kalkmulde extends as a triangle with the greater length between Kürten (western parts of the local areas Biesfeld , Blissenbach, Dürscheid , Lenzholz , Miebach and Spitze ) in the east and Katterbach in the west. There it borders directly on the Cologne district of Köln-Dünnwald . It has the shorter length between Lustheide in the area of the Children's Village Bethanien in the south and Seelsheide (Katterbach) in the north. In the north, the southern parts of Odenthal's local areas around Altehufe and Eikamp also belong to the Kalkmulde. On the southern edge, the Mulde borders the Variscan Mountains in the Milchborntal area . Here, Lower Devonian layers cover the Upper Devonian on the southern flank of the hollow. In the west, the tertiary fault line of the Rhine Valley forms the boundary.

The Strunde divides the hollow, which can also be seen on the surface as a depression in the terrain, into two wings of different sizes. In the extreme northeast, the Mulde is crossed by the Dürschbachtal . It sinks by approx. 40 to 60 meters into the surrounding mountains and has an average height of 160 to 200 meters.

The Paffrather Kalkmulde is naturally divided by the Bechener plateau (no.338.21) in the north, the Kürten plateau (no.338.220) and the Bärbroicher Höhe (no.338.224) in the east, from the Sülz plateau ( no.338.41) and the south Bensberg-Forsbacher mountain edge (No. 338.40) enclosed. The Lower Rhine Bay borders in the west .

landscape

Front of the reef In der Schlade in the Hebborn district in Bergisch Gladbach

In terms of landscape, open and frequent grassland with individual small forest areas and fruit-growing areas determine the appearance of the natural area. The beech forest dominates the steep slopes of the Strund valley . The course of the stream of the Strunde favored the settlement of protoindustrial commercial facilities, which are to be regarded as the roots of Bergisch Gladbach's industry.

Geology and soils

Seigerriss of the Paffrath Kalkmulde after Ulrich Jux

The stream shrinkage in Miebach can be seen on the left side of the picture, planted with fruit trees and spruces.

The rock strata that emerged in the hollow , mainly mass and plate limestone with a former content of ores, range from the lower Eifelium ( Middle Devonian ) to the Famennium ( Upper Devonian ). Chemical weathering processes led to the formation of inconspicuous sinkholes and weathering pockets .

Large parts of the Paffrath Kalkmulde are karst areas , in which the predominantly underground water balance results in continuous changes with cavities that often extend to the surface. In Miebach there is a stream shrinkage on the southeastern mountain slope , in which the water flowing off the mountain disappears in a superficial, slight hollow in the underground and only emerges again in the Strundetal .

The sequence of layers results from the trough profile shown on the right, which can mainly be assigned to the frasnium and the givetium on the basis of conductive fossil finds : You can get a good overview if you visit the geotope in the Schlade , which is designated as a ground monument . There are also boards that explain the individual stations and explain the overall situation in the limestone basin.

Frasnium

Hombacher layers
Slate
Refrather layers
Upper Plattenkalk

Givetium

Chert lot
Lower plate limestone
Büchel layers
Torringer layers
Sandy Honseler layers

Loess loam and deep to medium-depth weathered loam predominate as soils. The limestone's own water balance, the flora and fauna typical of it and the abundant land use set the limestone basin apart from the surrounding landscape. This applies in particular to the transition to the Paffrath limestone terrace to the west, which is characterized by a sunken trough base below a gravel and sand cover .

In contrast to the limestone basin, the mountainous region surrounding the north, east and south has predominantly clay slate and gray wacke . The different levels of resistance of the rocks within the hollow are reflected in the form of towering dolomitized limestone and reef limestone.

Fossils

The crab of the Strund valley (Latin: Montecaris strunense ) is a rare fossil from the Ulrich Jux collection .

Ctenurella gladbachensis is an approx. 19 cm long shellfish from the Strundetal . The species epithet refers to the Bergisch Gladbach site.

The excellent fossil conservation made this area geologically known far beyond Germany. As early as the end of the 18th century, paleontological studies with material from the Paffrath Mulde were published. The old quarries in the area, where limestone and dolomite were mined 100 years ago and which served as excellent sites for fossils , have long been abandoned. Fossil finds are still possible here, but usually rarely. A very important find of recent times was the new building of the district house in Bergisch Gladbach-Heidkamp in 1970. In the center of the Paffrather Mulde the hitherto unknown Knobbissen formation of the famennium was cut.

The collection of finds from the Paffrath Kalkmulde, which was previously exhibited in the Bergischer Löwe community center in Bergisch Gladbach, has mainly been stored in the basement of Villa Zanders for cost reasons . There is only a small selection of fossils in the exhibition in the Bergisches Löwen.

Research history

The investigation of the geology of the Paffrath Kalkmulde began as early as the first half of the 19th century. In 1837 Heinrich Ernst Beyrich examined the stratigraphy of the Kalkmulde for the first time and divided the sequence into an older and a younger one. In the second edition of Lethaea Geognostca (1851–1856) by Heinrich Georg Bronn , the two layers were assigned to the Middle Devon. In 1842 Roderick Murchison and Adam Sedgwick already suspected a trough structure.

The particular wealth of fossils in the limestone basin attracted numerous paleontological researchers to the area. Mention should be made of Franz Beuth , Johann Samuel Schröter , August Goldfuß , Adolphe d'Archiac and Édouard de Verneuil .

The first systematic recording of the sequence of layers was made by geologist Georg Meyer in 1879, who also used the paleontological findings to determine the time. Although its determination was inconsistent in detail, it first recorded the special sequence of layers of the research area and confirmed the assumption made by Murchison & Sedgwick in 1842 regarding the structure of the trough and Beyrich's determination of the age. Other editors such as Fritz Frech (1886) and E. Schulz (1883) confirmed Meyer's results, but in some cases they were also misleading with their results. Frank Winterfeld (1896) questioned the research of Meyer's successors and took a critical look at his results himself, which he confirmed in principle but corrected in detail.

Winterfeld's investigations, which Gotthard Fliegel mapped in 1923 as part of his geological survey of the Rhineland, finally revealed the correct profile assignment of the stratifications. Also deposits of reef limestone, which Meyer noticed but could not be classified by him, were assigned to the correct layers by Winterfeld's studies. Fliegel, in turn, introduced new names for the layers found in his mapping, which were then also included in the official geological map series 1: 25,000. In 1963 Ulrich Jux revised the names of Fliegel and re-summarized them according to contemporary geological knowledge. The newer geological maps were based on his research.

In January 2000, the North Rhine-Westphalia Geological Service carried out a 500 m deep test borehole, with the help of which, after more than 200 years of geological research, the rock sequence could be finally determined based on the findings of key fossils, mainly conodonts .

Mining

During the deposition of the middle and upper Devonian layers, heavy metal quantities fixed in the rock. They could be leached and mobilized from the rock by saline and higher temperature solutions. The seawater of the Tertiary floods in the North Sea released the metal ions . The dolomitization of the limestones was associated with a decrease in volume, which made it easier for the ore-containing solutions to penetrate the rock. There was an exchange of substances and recrystallization . During this process, iron , zinc in the form of calamine , arsenic and manganese were released, which formed corresponding deposits .

In the Bensberg ore district , around 60 ore mines and 14 lignite mines were lent out in the Paffrath Kalkmulde area in the last half of the 19th century . The largest ore mines included the Grube Consolidierte Catharina II , Grube Luther , Grube Eduard & Amalia , Grube Prinz Wilhelm , Grube Britannia and Grube Albert .

Nature reserves

The following nature reserves are located in or on the Paffrather Kalkmulde.

literature

Ulrich Jux : Bibliography on the geology and palaeontology of the Bergisch Gladbach-Bensberger area 1775–1977 (= special publication of the Geological Institute of the University of Cologne, vol. 32). Cologne 1977
Christoph Hartkopf-Fröder, Maurice Treel: Late Famennian miospore assemblages from the Bergisch Gladbach-Paffrath Syncline, Rhenish Slate Mountains, Germany , in: Annales de la Société géologique de Belgique 116, 1994, pp. 333–357 ( digital )
Christoph Hartkopf-Fröder, Matthias Piecha (Eds.): Palaeontology and facies of the late Famennian in the Paffrath Syncline (Rhenish Massif, Germany) (= Courier Research Institute Senckenberg Vol. 251). Frankfurt a. M. 2004, ISBN 978-3-510-61371-7
Ulrich Jux: 4.1.13 Bergisch Gladbach-Paffrather Mulde. In: German Stratigraphic Commission (ed.), Stratigraphie von Deutschland VIII. Devon , (= series of publications of the German Society for Geosciences, Vol. 52). Hannover 2008, ISBN 978-3-510-49200-8 , pp. 402-416.

Web links

The article is based on the following three websites, among others.

Sven von Loga: Find places and fossils: Paffrather Mulde (Bergisch Gladbach). Retrieved October 2, 2012 .
Upper Devon of the Paffrather Mulde. Geological Service NRW, accessed on September 21, 2007 .
Brochure state meeting NRW on May 2nd, 2004 in Bergisch Gladbach-Herkenrath. Naturfreunde Köln, accessed on September 21, 2007 .

Individual evidence

↑ ^a ^b ^c ^d ^e ^f Handbook of the natural spatial structure of Germany: Sheet 108/109: Düsseldorf / Erkelenz (Karlheinz Paffen, Adolf Schüttler, Heinrich Müller-Miny) 1963; 55 p. And digital version of the corresponding map (PDF; 7.4 MB)
↑ ^a ^b ^c ^d Ulrich Jux: On the stratigraphic structure of the Devonian profile of Bergisch Gladbach (Rheinisches Schiefergebirge). In: Decheniana , Natural History Association of the Rhineland and Westphalia, Vol. 127: Heft 1/2, 1964, pp. 159-174.
↑ Hans Martin Weber: World-famous fish and crabs from the Devonian of the Strundet Valley in Bergisch Gladbach , in: Fundgeschichten - Archeology in North Rhine-Westphalia , Writings of the Bodendenkmalpflege in NRW, Volume 9, Ed. Thomas Otten, Römisch-Germanisches Museum der Stadt Köln and Verlag von Philipp Zabern, Mainz 2010, p. 24 ff. ISBN 978-3-8053-4204-9
^ Franz Beuth : Juliae et montium subterranea sive fossilium variorum per utrumque ducatum hinc inde repertorum syntagma, in quo fingula breviter recensentur ac describuntur, quae quidem collecta hucusque servantur in museo Francisci Beuth , Düsseldorpii 1776
↑ Johann Samuel Schröter : Of the petrified Amonites and Terebratulites, especially of the Terebratulites in the Bergisch and in the Eifel , in: Abh. 2, Halle 1777, pp. 335–404.
↑ ^a ^b ^c Hans Dieter Hilden: Geology of the Paffrather Kalkmulde In: Das Erbe des Erzes . Volume 3, The pits in the Paffrather Kalkmulde and Westphalia, Bergisch Gladbach 2006, ISBN 3-932326-49-0
^ Herbert Stahl (editor), Gerhard Geurts , Hans-Dieter Hilden, Herbert Ommer : Das Erbe des Erzes, Volume 3, The pits in the Paffrather Kalkmulde. Bergisch Gladbach 2006, ISBN 3-932326-49-0

[HNG-1] ↑ ^a ^b ^c ^d ^e ^f Handbook of the natural spatial structure of Germany: Sheet 108/109: Düsseldorf / Erkelenz (Karlheinz Paffen, Adolf Schüttler, Heinrich Müller-Miny) 1963; 55 p. And digital version of the corresponding map (PDF; 7.4 MB)

[jux-decheniana-2] Ulrich Jux: On the stratigraphic structure of the Devonian profile of Bergisch Gladbach (Rheinisches Schiefergebirge). In: Decheniana , Natural History Association of the Rhineland and Westphalia, Vol. 127: Heft 1/2, 1964, pp. 159-174.

[3] Hans Martin Weber: World-famous fish and crabs from the Devonian of the Strundet Valley in Bergisch Gladbach , in: Fundgeschichten - Archeology in North Rhine-Westphalia , Writings of the Bodendenkmalpflege in NRW, Volume 9, Ed. Thomas Otten, Römisch-Germanisches Museum der Stadt Köln and Verlag von Philipp Zabern, Mainz 2010, p. 24 ff. ISBN 978-3-8053-4204-9

[4] Franz Beuth : Juliae et montium subterranea sive fossilium variorum per utrumque ducatum hinc inde repertorum syntagma, in quo fingula breviter recensentur ac describuntur, quae quidem collecta hucusque servantur in museo Francisci Beuth , Düsseldorpii 1776

[5] Johann Samuel Schröter : Of the petrified Amonites and Terebratulites, especially of the Terebratulites in the Bergisch and in the Eifel , in: Abh. 2, Halle 1777, pp. 335–404.

[hilden-6] Hans Dieter Hilden: Geology of the Paffrather Kalkmulde In: Das Erbe des Erzes . Volume 3, The pits in the Paffrather Kalkmulde and Westphalia, Bergisch Gladbach 2006, ISBN 3-932326-49-0

[Bergbau-7] Herbert Stahl (editor), Gerhard Geurts , Hans-Dieter Hilden, Herbert Ommer : Das Erbe des Erzes, Volume 3, The pits in the Paffrather Kalkmulde. Bergisch Gladbach 2006, ISBN 3-932326-49-0