Vulkaneifel

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Ernstberg ( Erresberg , Erensberg ), highest mountain in the Vulkaneifel and an elevation of the Westeifel volcanoes
Eifel, u. a. with Vulkaneifel (diagonally in the middle right)

The Vulkaneifel is located in Rhineland-Palatinate and up to 699.8  m above sea level. NHN high region of the Eifel , which is characterized by its geological history and present , which is particularly linked to volcanism . The typical Eifel maars and numerous other testimonies to volcanic activities such as volcanic structures, lava flows and volcanic craters such as the caldera of the Laacher See are characteristic of their landscape . The Vulkaneifel, of which large parts are in the Vulkaneifel Nature Parkis still volcanically active today. A characteristic of this volcanic activity are escaping volcanic gases, such as in the Laacher See.

The Vulkaneifel region is not the same as the district of the same name, which was called the Daun district until a few years ago .

geography

location

The Wingertsbergwand gives an impression of the magnitude of the volcanic ash ejected during the eruption of the Laacher See volcano.

The Vulkaneifel extends from the Rhine to the Wittlich valley . It borders to the south and southwest of the southern Eifel , on the west by the Luxembourg and Belgian Ardennes and the north by the North Eifel with the High Fens . In the east, the Rhine forms the geographical border, volcanism does not cross it.

The Vulkaneifel is naturally divided into three parts:

The centers of the Vulkaneifel form the region around Daun, Ulmen and Manderscheid and the areas in the district of Mayen-Koblenz .

The entire Vulkaneifel extends over an area of ​​around 2000 km² and is inhabited by more than 200,000 people (as of 2007).

mountains

The volcanoes of the Eifel include - sorted by height in meters (m) above mean sea level (NHN), in the following arranged according to the time of volcanism:

→ See also: List of mountains and elevations in the Eifel

Volcanic landforms

Basalt columns in the Ettringer Lay

The landscape of the Vulkaneifel is shaped by the forms of young volcanism. Volcanic craters, mighty pumice and basalt deposits and maars create a varied landscape that impressively tells of the geologically very recent events.

The volcanic forms of the Eifel can be distinguished based on their age. The much older volcanic structures in the Hocheifel have already been severely eroded , while the younger volcanic structures in the West and East Eifel are often still well preserved. In particular, the soft tuff deposits from volcanic eruptions, which are very easily eroded, are still widespread here.

Most of the volcanic structures of the Hocheifel are isolated as isolated peaks or set up in rows on the more or less flat plateau. These crests have a circular or elliptical plan. In the center of the crests there are often club-shaped or disc-shaped basalt bodies surrounded by tufa layers. These are chimney fillings that have been released from erosion as hardness . The basalt, which penetrated into cinder cones or tuff blankets, formed columnar cooling structures ( lava columns ) during the slow solidification , the longitudinal axes of which are arranged perpendicular to the outer surfaces of the basalt deposits. Larger lava flows from the Hocheifel volcanoes are not known.

The more recent volcanic structures in the West and East Eifel consist mainly of cinder cones, the flanks of which are often broken in one or more places. The volcanoes often have several eruption centers that have merged into a complex volcanic building, and with their lava flows and ejecta almost completely cover the older subsoil. Many volcanoes have a central crater from which lava flows emanate. However, numerous volcanic vents no longer have a volcanic structure or crater and can only be traced using special geological and geophysical methods.

Starting from the central volcanic structures, lava flows have spread over several kilometers in the West and East Eifel. They often used existing valleys and blocked them, so that the stream or river had to find a new way. Examples of this can be found in the Nette valley or in the Ueß valley near Bad Bertrich .

Tephra layers in a quarry near Weibern in the Brohl valley

The tuff blankets of the Eastern Eifel are of great importance. As a result of repeated eruptions, the volcanoes have deposited several meters thick pyroclastic deposits over wide areas , which have mainly been preserved in the Neuwied Basin , but can also be found in remnants everywhere in the Eastern Eifel and in parts of the Westerwald. The pyroclastic flows of the volcanoes, like the lava flows, have filled entire valleys, for example in the Brohl valley north of the Laacher See, where the deposits are called trass .

The volcanic craters are often part of the volcanic structures . These round, bowl-shaped depressions were formed near or above the chimney of a volcanic eruption, either by the evacuation of the chimney by volcanic explosions or by the collapse of the cover layers of a magma chamber emptied by the eruption .

The Weinfelder or Totenmaar , one of the three Dauner Maars

The craters at a steam explosion originated, are crater lakes called. They are surrounded by a flat wall of volcanic ejecta. The youngest of them are only a little older than 11,000 years. Examples of Eifelmaars are the Weinfelder Maar , the Schalkenmehrener Maare or the Pulvermaar . The maars are not only a peculiar landscape form of the Vulkaneifel, but also a valuable archive of the landscape and climate history. In them offshore sediments from where the ashes were preserved animals and plants of other volcanic eruptions and the remains of which conclusions could be drawn on the then prevailing climate. Most of the maars are found in the outer regions of the volcanic West Eifel.

Of similar origin as the Maare existing in the volcanic Eifel are Diatreme . They lack crater walls and a lake, they are volcanic breakthrough tubes that go back to a single event. Examples can be found in the Virneburg area .

Crater shapes created by the collapse of a magma chamber are called caldera . They are usually much larger than the maars. Examples of calderas are the Laacher See, the Wehrer Kessel and the Riedener Kessel, which is largely covered by tuff covers .

Volcanic activity

The volcanism of the Eifel began 50 million years ago in the Tertiary and has continued into the geological present. He created numerous landscape-defining volcanic structures, lava flows and extensive ceilings of volcanic ejecta made of tuff and pumice, which have formed the basis of significant mining activities for the extraction of building materials since Roman times.

Causes of volcanism in the Eifel

Illustration of a plume

Some scientists assume that the cause of the Eifel volcanism is a so-called hotspot or plume , which is located deep below the Eifel. Some scientists point out that the distribution of volcanoes and their sequence do not correspond to that of a hotspot. It is undisputed that magma rises from the upper areas of the earth's mantle and either rises directly to the earth's surface or collects in a magma chamber that is still several tens of kilometers deep at the base of the earth's crust , from which magma rises at irregular intervals and causes volcanic eruptions .

By means of seismographic measurements it could be proven that under the Eifel there is a 1000 to 1400 ° C hot zone (plume) that is 200 ° C hotter than its immediate surroundings. Melting processes are associated with an increase in volume, which must be noticeable in the form of land uplifts. In fact, the Eifel has long been known as an uplift area. For 800,000 years, the uplift in the Rhenish slate mountains has accelerated to an average of 0.12 mm per year. But there are areas in the central Eifel that have since risen like a cathedral by up to 300 m, which corresponds to a rate of 0.35 mm per year.

Volcanism of the Hocheifel

The land crown near Bad Neuenahr , the remains of a tertiary volcano

The first volcanic eruptions took place in the early Tertiary , mainly in the Hocheifel, before the volcanic activity in the Siebengebirge and Westerwald . Particularly in an area stretching from north to south, about 30 km long between the places Ulmen and Adenau, almost exclusively basalts were mined, and to a lesser extent , andesites , latites and trachytes that emerged from the basalt through magmatic differentiation . Larger lava flows and blankets of volcanic ash as in the younger volcanic regions of the East and West Eifel are missing here. Outside of this volcanic center, further scattered occurrences of tertiary volcanoes are known, especially in the East Eifel, especially in the area of ​​the Laacher See and the Ahr . As it approaches the volcanic area of ​​the Siebengebirge, the frequency of occurrences increases again sharply. A systematic distribution of the total of around 350 deposits cannot be identified; the earth's crust was riddled with a shotgun by the rising magmas.

In contrast to this, the distribution of the various types of rock, which differ in their quartz content, is systematic; it is ring-shaped with the most quartz-rich rocks in the center. This distribution speaks for the origin from a large magma chamber.

The Hocheifel volcanism died out at about the same time as that of the Siebengebirge about 15 to 20 million years ago.

Well-known tertiary volcanoes are the Arensberg near Hillesheim or the Dächelsberg near Oberbachem .

Volcanism in the West Eifel

Ulmener Maar , viewed from the Ulmener Burgen

In contrast to that of the Hocheifel, the volcanism of the West and East Eifel is much younger than that of the Siebengebirge and the Westerwald. It began in the West Eifel in the area of ​​Daun, Hillesheim and Gerolstein about 700,000 years ago and created a 50 km long chain of about 100 cinder cones and craters between Bad Bertrich and Ormont, running from northwest to southeast .

Examples of such volcanic structures are the Wartgesberg near Strohn , the Manderscheid volcanic group, the Radersberg near Dreis-Brück , the Steffelnkopf near Steffeln , or the Goldberg near Ormont as the northernmost volcano in the West Eifel.

The maars are particularly common in the West Eifel, especially in the outer areas of the volcanic field. Of the more than 50 maars, eight are still filled with water today. A further 80 former eruption centers have no crater or volcano and can only be detected using special methods. In the east, the volcanic field of the West Eifel merges into the older one of the Hocheifel. The Westeifel volcanoes have been the subject of lively research since the beginning of the 19th century, and the maars in particular have been thoroughly examined. The volcanic rocks of the West Eifel are very poor in quartz and belong to the rock types of phonolites , basanites , tephrites and above all the foidites . A special feature of the maars in particular are the rocks ejected when they erupt, the composition of which is similar to that of the earth's mantle, such as dunites , harzburgites and peridotites .

Maars were formed during the entire active period of the West Eifel. The most recent volcanic events in the West Eifel are the formation of the powder maar 20,000 years ago and the Ulmen maar around 11,000 years ago.

Volcanism in the Eastern Eifel

Angular discordance in obliquely layered tuffs of the East Eifel

In the Eastern Eifel, volcanism began around 500,000 years ago in the area of ​​today's Laacher See and expanded south to the Neuwied Basin, and to the east it crossed the Rhine. In the west, the volcanic area of ​​the Laacher See is relatively close to the easternmost foothills of the West Eifel volcanism, the Niveligsberg near Drees and the Booser Maaren. Due to the diverse volcanic manifestations and the special mineralogical composition of the rocks occurring here, the Osteifler volcanic area has been scientifically researched since the 18th century.

Three volcanic phases have been proven on the basis of the volcanic ejecta and the type of volcanic activity. In an early phase with a focus on the area of ​​the Riedener Kessel between Kempenich , Engeln, Rieden and Bell , tuffs and lavas with a basaltic and phonolithic composition were extracted. Then, in the longest of the three phases, numerous basalt volcanoes, cinder cones, tuff covers and kilometer-long lava flows were created. In the last phase, only tuffs were extracted, which settled as lapilli tuff or fine-grained trass , especially in the east of the volcanic area. This phase began in the area of ​​the Wehrer Kessel and came to a catastrophic conclusion with the eruption of the Laacher See volcano. The amount of basalt lavas , pumice and ash tuffs produced by the volcanoes was far greater here than in the West Eifel.

The people who lived in this area at the end of the last ice age about 13,000 years ago mostly stayed away from the volcanoes, as the rarity of archaeological finds in direct connection with volcanic evidence shows.

The eruption of the Laacher See volcano

The Laacher See in winter

→ Main article: Laacher See

The volcanism of the Eastern Eifel came to a temporary end with a massive volcanic eruption, which after the emptying of the magma chamber under the volcano led to the collapse of a caldera, in which today's Laacher See was formed. It was one of the last and most dramatic eruptions, found around 10,980-10,960 BC. BC, a little over 13,000 years ago.

At this time, a major eruption occurred: volcanic cones in the area of ​​today's lake exploded, lava fragments and blown loose material ( bombs , lapilli, ashes ) formed up to 30 m high banded tuff, pumice and ash layers when they were deposited on the ring wall of the basin. At a distance of 15 km, near Neuwied am Rhein , these layers are still 6 m thick. Dust-fine material was transported in the upper atmosphere to Bornholm in the Baltic Sea and to northern Italy and can be detected as a dark strip in the corresponding soil horizons . At least two megatons of sulfur must have been transported into the stratosphere during the eruption .

Around 16 cubic kilometers of volcanic loose mass were ejected within a short time. This corresponds to about five times the flow rate of Vesuvius during its great eruption in 79 AD, which led to the fall of Pompeii . In the Eifel as well as on Vesuvius, pyroclastic currents caused the greatest devastation. From the Laacher volcano they mainly flowed into the Brohl valley, where they left deposits of porous rock up to 60 m high. The 50 m high Wingertsbergwand testifies to this. The eruption produced almost twice as much material as all 300 cinder cones in the East and West Eifel combined. How many people perished in the sparsely populated area is not known, however, remains of a human skeleton were found in the base layers of the Laacher-See-Bimstuffe at the foot of the Kettiger Höhe near Weißenthurm . According to current studies, the magma chamber under the Laacher See is filling up again, but the next eruption is not expected for several thousand years.

Future development

Volcanic phenomena that are still active today are the numerous gas leaks ( mofettes ), mineral springs and some cold water geysers . The last eruption of a volcano in the East Eifel was 13,000 years ago, in the West Eifel 11,000 years ago. But that doesn't mean that no further outbreaks are to be expected in the future.

In the Eastern Eifel, volcanism did not run smoothly, but rather episodically. A major Plinian eruption was followed by several smaller eruptions hundreds to thousands of years apart. Then there was a longer break of up to 150,000 years. There have been at least three such periods in the past 500,000 years. It is therefore possible that the Laacher See eruption initiated a new episode and that we will be able to observe the formation of new cinder cones or maars in the future. When that could be cannot be predicted.

Meaning of the Eifel volcanism

The catastrophic pumice eruption of the Laacher See volcano has not only caused destruction. The extensive coverage and thus conservation of the post-glacial landscape surface by the pumice layers of the “Laacher-See-Tephra” enables scientific research into the state of the Eifel region 13,000 years ago. In addition, the volcanism of the Eifel is of great importance for the Eifel's economy, the most important branches of the economy are the extraction of building materials and, to an ever greater extent, tourism. The variety of volcanic phenomena has also given rise to the designation of several geoparks and the establishment of several special museums.

Building materials industry

Tufa quarry in Ettringen

The former volcanism of the Eifel also has economic benefits. The pumice deposits that the Laacher See volcanoes deposited more than 10,000 years ago were already mined by the Romans for the extraction of mortar and building blocks in opencast mines and underground . The deposits led to the development of a pumice stone industry in the Middle Ages and later in the 19th century, which gained enormous importance in the 20th century in particular. Around 40 percent of all the building blocks used for the reconstruction of the Federal Republic after the Second World War came from the huge pumice area of ​​the Laacher volcano. The enormous importance of pumice processing goes back to the building inspector Ferdinand Nebel , who in 1845 developed a process to produce lightweight building blocks from ground pumice with the addition of milk of lime . The deposits are now largely exhausted, the mining is approaching the outbreak centers themselves, but where the quality of the raw material is deteriorating due to the increasing proportion of adjacent rock.

tourism

There are nine holiday regions in the Vulkaneifel, some of which arose from voluntary amalgamations of various association communities. The municipalities of Daun , Ulmen and Wittlich-Land appear as GesundLand Vulkaneifel . The municipality of Gerolstein markets itself under the name of the Gerolsteiner Land holiday region . The Verbandsgemeinde Obere Kyll appears as the holiday region Obere Kyll and the Verbandsgemeinde Hillesheim as the holiday region Hillesheim . The municipalities of Mendig , Pellenz and the municipality of Brohltal have merged to form the Laacher See holiday region . The municipality Kelberg is known as holiday region Kelberg active and the municipality Vordereifel under holiday region Vordereifel . The Maifeld community can be found under the name Maifeld Holiday Region. In addition, there is the amalgamation of the association communities of Adenau , Brohltal, Kelberg and the association community of Vordereifel as the Nürburgring adventure region .

Tourism is an important economic factor in the Vulkaneifel. The focus is on volcanism, nature, hiking, cycling and health.

nature

The nature and untouched landscape, which still bear clear traces of the volcanic past, are two of the most important factors in the Vulkaneifel. It is now recognized that they serve as a therapeutic landscape and can contribute to salutogenesis , i.e. the development and maintenance of health.

hike

The Vulkaneifel has a well-developed and densely signposted network of hiking trails. In addition to the Eifelsteig and the Lieserpfad , the Vulkaneifel paths or the dream paths also criss-cross heights and valleys. The various local hiking trails are also laid out according to high quality criteria.

To go biking

Both cyclists and mountain bikers will find routes in the Vulkaneifel that are specially tailored to their needs. While paths such as the Maare-Mosel-Radweg , the Eifel Volcano-Rad-Route , the Kosmosradweg , the Mineralquellen-Route and the Eifel-Ardennen-Radweg are designed for a leisurely ride, ambitious athletes will find themselves in the Trail Park with its 750-kilometer route network and the Koulshore, in which driving techniques can be practiced.

health

In addition to the already existing natural resources such as fresh air, clear water and wooded surroundings, there are numerous medical facilities in the Vulkaneifel, many of them specializing in special fields. The cities of Daun and Manderscheid as well as Bad Bertrich are designated and recognized health resorts .

Geoparks and museums

The cold water geyser in Wallenborn , one of the sights of the German Volcano Road

There are two Geoparks in the Vulkaneifel : the Vulkaneifel Nature and Geopark , which is part of the UNESCO Global Geoparks , and the Laacher See National Geopark .

The Laacher See National Geopark encompasses the volcanic areas of the Eastern Eifel that extend as far as the Rhine. The visitor center of the volcano park in the district of Mayen-Koblenz is located between Plaidt and Saffig in the Rauschermühle . Attached to the center is the Rauscher Park in the Valley of the Nette, which deals with the volcanic history of the area and the use of the basalt lava deposits by the Romans. The volcano park comprises a network of four routes that connect a total of 26 stations. The German Volcano Museum Mendig - Lava Dome, opened in 2006, is also part of the volcano park . In the Meurin Trass mine near Kretz , the Meurin Roman mine provides an insight into the underground mining of the trass building material, which was already coveted by the Romans. The Terra Vulcania Museum in Mayen deals with the 7,000-year history of basalt mining and the volcanic raw material pumice is treated in the German pumice museum in Kaltenengers . Another attraction in the volcano park is the Andernach geyser , the world's highest cold water geyser.

The information center of the Brohltal / Laacher See volcano park, which was primarily designed around the eruption of the Laacher See volcano, is located in Niederzissen . Five hiking routes lead through the lower, middle and upper Brohl valley , around the Laacher See and through the Vinxtbachtal, a higher-level tour combines the highlights of all hiking routes and is designed for use by car or bike. The geological conditions are explained on large information boards along the routes. Part of the Brohltal / Laacher See volcano park is the geology adventure garden in Engeln and the museum island in Weibern , which deals with the tuff mining of the region, which was important in the past.

The UNESCO Global Geopark Vulkaneifel, at the same time nature and Geopark Vulkaneifel, summarizes the volcanologically interesting areas of the West Eifel. Here are the Geopath Hillesheim the, volcano route as part of the Geo-Route Manderscheid and the volcano trail in Strohn three geological trails emerged. The Geopark covers large parts of the municipalities of Gerolstein , Daun , Kelberg, Ulmen and Wittlich-Land . In Daun, the Daun volcano museum is open to visitors, in Strohn the volcanic house offers interesting facts about the volcanism of the Eifel and in Manderscheid the maars are the focus of the Maar museum Manderscheid . Further museums with information on Eifel volcanism can be found in Hillesheim, Jünkerath and Gerolstein.

The geological features of the Vulkaneifel are also made accessible by the German Volcano Road . It touches 39 of the most important geological, cultural-historical and industrial-historical sights in the Vulkaneifel and in this way connects the two existing National GeoParks of the Eifel.

literature

Web links

Commons : Geopark Vulkanland Eifel  - Collection of images, videos and audio files

Individual evidence

  1. ↑ Map service of the landscape information system of the Rhineland-Palatinate nature conservation administration (LANIS map) ( notes )
  2. ↑ GeoViewer of the Federal Institute for Geosciences and Raw Materials ( information )
  3. ↑ Meyer 1986, p. 272 ​​f.
  4. ↑ Meyer 1986, p. 305 f.
  5. ↑ Meyer 1986, p. 308.
  6. ^ W. Meyer, J. Stets: Pleistocene to Recent tectonics in the Rhenish Massif.  ( 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. 2002. (PDF, English; 135 kB)@1@ 2Template: Dead Link / www.njgonline.nl  
  7. ↑ Meyer 1986, p. 267 f.
  8. ↑ Meyer 1986, pp. 305 ff.
  9. ↑ Schmincke 2009, p. 132.
  10. ↑ Frank G. Fetten: The powder maar and its volcanic origin. In: Heimatjahrbuch 2009. Vulkaneifel district, accessed on April 9, 2019 .
  11. ↑ Schmincke 2009, p. 25.
  12. ↑ Meyer 1986, p. 365 ff.
  13. Jump up ↑ M. Baales, O. Jöris, M. Street, F. Bittmann, B. Weninger, J. Wiethold: Impact of the Late Glacial Eruption of the Laacher See Volcano, Central Rhineland, Germany. In: Quaterny Research. 58, 2002, pp. 273-288.
  14. ↑ Meyer 1986, p. 431.
  15. ↑ Jürgen Kunow, Hans-Helmut Wagner (Ed.): Prehistory in the Rhineland. (= Yearbook of the Rhenish Association for Monument Preservation and Landscape Protection 2005). ISBN 3-88094-814-3 , p. 146.
  16. ↑ Unusually deep earthquakes indicate movements of magmatic fluids under the Laacher See. In: Communication from the State Office for Geology and Mining Rhineland-Palatinate. January 9, 2019, accessed January 11, 2019 .
  17. ↑ Lecture by Prof. H. U. Schmincke 2006 (PDF file; 227 kB), accessed June 13, 2011.
  18. ↑ Meyer 1986, p. 424.
  19. ↑ Make 2 out of 1: Nationaler GeoPark Vulkaneifel is divided into two Geoparks , from July 6, 2016, accessed on July 31, 2017, at nationale-geopark.de
  20. ↑ Homepage of the volcano park in the Mayen-Koblenz district. Retrieved January 12, 2008.
  21. ↑ Homepage of the Brohltal / Laacher See volcano park. Retrieved January 12, 2008.
  22. ↑ Vulkanpark information center. Retrieved May 26, 2019.
  23. ↑ Homepage of the German Volcano Road. ( Memento of the original from May 31, 2008 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. Retrieved January 12, 2008. @1@ 2Template: Webachiv / IABot / www.deutsche-vulkanstrasse.com

Coordinates: 50 ° 17 '  N , 7 ° 0'  E