La Mansonnière cave
Encyclopedia
La Mansonnière cave is a chalk
cave
in northern France
. It was discovered in 1977.
printed by La MJC de l'Aigle and was reported to the French Federation of Speleology at the St Etienne de Rouvray Conference.
in south eastern Orne county, Normandy
. It lies in a disused chalk
mine used at the time as a mushroom farm
. The entrances were walled up, but permission was obtained to gain entry to the labyrinth
, referred to by the mushroom
workers as 'clay pockets'. It was clear that extensive digging could link up the truncated sections to lengthen the cave from 140 metres to more than one kilometre, making it one of the longest chalk caves. The tunnels are about 1.5 metres high but are extensively choked with sediment
.
later renamed the cave and engaged in extensive digging, removing much of the valuable varve
deposits which the SCRPLA had hoped to preserve for study by professional soil scientists
. The SCRPLA produced a study of the cave which has since been added to by other groups. The cave suffered considerable vandalism
when the mushroom farm ceased activity, but has since been re-gated. The cave is not related to any current hydrogeological
system. There are very extensive (30 km) active karst
systems under the nearby Pays d'Ouche
district although extensive exploration by the SCRPLA has not managed to penetrate any of these. However, they have located detailed descriptions of at least one cave explored by the Paris
ian water authorities in the nineteenth century. For more information on Chalk karst, the works of the great pioneer speleologist
A.E.Martel should be consulted.
Chalk
Chalk is a soft, white, porous sedimentary rock, a form of limestone composed of the mineral calcite. Calcite is calcium carbonate or CaCO3. It forms under reasonably deep marine conditions from the gradual accumulation of minute calcite plates shed from micro-organisms called coccolithophores....
cave
Cave
A cave or cavern is a natural underground space large enough for a human to enter. The term applies to natural cavities some part of which is in total darkness. The word cave also includes smaller spaces like rock shelters, sea caves, and grottos.Speleology is the science of exploration and study...
in northern France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
. It was discovered in 1977.
Discovery
La Mansonnière cave was discovered by the Speleo Club du Rond Point de L'Aigle (SCRPLA) in 1977. The discovery was published in the bulletinBulletin
Bulletin can refer to:Periodicals * The Bulletin, a now defunct Australian magazine* The Bulletin , an alternative weekly published in Montgomery County, Texas, United States...
printed by La MJC de l'Aigle and was reported to the French Federation of Speleology at the St Etienne de Rouvray Conference.
Origins
The Cave was originally called "La Grotte de Bellou sur Huisne", after the name of the local communeCommune
Commune may refer to:In society:* Commune, a human community in which resources are shared* Commune , a township or municipality* One of the Communes of France* An Italian Comune...
in south eastern Orne county, Normandy
Normandy
Normandy is a geographical region corresponding to the former Duchy of Normandy. It is in France.The continental territory covers 30,627 km² and forms the preponderant part of Normandy and roughly 5% of the territory of France. It is divided for administrative purposes into two régions:...
. It lies in a disused chalk
Chalk
Chalk is a soft, white, porous sedimentary rock, a form of limestone composed of the mineral calcite. Calcite is calcium carbonate or CaCO3. It forms under reasonably deep marine conditions from the gradual accumulation of minute calcite plates shed from micro-organisms called coccolithophores....
mine used at the time as a mushroom farm
Fungiculture
Fungiculture is the process of producing food, medicine, and other products by the cultivation of mushrooms and other fungi.The word is also commonly used to refer to the practice of cultivating fungi by leafcutter ants, termites, ambrosia beetles, and marsh periwinkles.- Introduction :Mushrooms...
. The entrances were walled up, but permission was obtained to gain entry to the labyrinth
Labyrinth
In Greek mythology, the Labyrinth was an elaborate structure designed and built by the legendary artificer Daedalus for King Minos of Crete at Knossos...
, referred to by the mushroom
Mushroom
A mushroom is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground on soil or on its food source. The standard for the name "mushroom" is the cultivated white button mushroom, Agaricus bisporus; hence the word "mushroom" is most often applied to those fungi that...
workers as 'clay pockets'. It was clear that extensive digging could link up the truncated sections to lengthen the cave from 140 metres to more than one kilometre, making it one of the longest chalk caves. The tunnels are about 1.5 metres high but are extensively choked with sediment
Sediment
Sediment is naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of fluids such as wind, water, or ice, and/or by the force of gravity acting on the particle itself....
.
Exploration
French caversCaving
Caving—also occasionally known as spelunking in the United States and potholing in the United Kingdom—is the recreational pastime of exploring wild cave systems...
later renamed the cave and engaged in extensive digging, removing much of the valuable varve
Varve
A varve is an annual layer of sediment or sedimentary rock.The word 'varve' is derived from the Swedish word varv whose meanings and connotations include 'revolution', 'in layers', and 'circle'. The term first appeared as Hvarfig lera on the first map produced by the Geological Survey of Sweden in...
deposits which the SCRPLA had hoped to preserve for study by professional soil scientists
Soil science
Soil science is the study of soil as a natural resource on the surface of the earth including soil formation, classification and mapping; physical, chemical, biological, and fertility properties of soils; and these properties in relation to the use and management of soils.Sometimes terms which...
. The SCRPLA produced a study of the cave which has since been added to by other groups. The cave suffered considerable vandalism
Vandalism
Vandalism is the behaviour attributed originally to the Vandals, by the Romans, in respect of culture: ruthless destruction or spoiling of anything beautiful or venerable...
when the mushroom farm ceased activity, but has since been re-gated. The cave is not related to any current hydrogeological
Hydrogeology
Hydrogeology is the area of geology that deals with the distribution and movement of groundwater in the soil and rocks of the Earth's crust, . The term geohydrology is often used interchangeably...
system. There are very extensive (30 km) active karst
Karst topography
Karst topography is a geologic formation shaped by the dissolution of a layer or layers of soluble bedrock, usually carbonate rock such as limestone or dolomite, but has also been documented for weathering resistant rocks like quartzite given the right conditions.Due to subterranean drainage, there...
systems under the nearby Pays d'Ouche
Pays d'Ouche
The Pays d'Ouche is an historical and geographical region in Normandy. It extends from the southwest of Évreux up to Bernay and Beaumont-le-Roger as a northern limit, and down to L'Aigle and to Gacé in the south....
district although extensive exploration by the SCRPLA has not managed to penetrate any of these. However, they have located detailed descriptions of at least one cave explored by the Paris
Paris
Paris is the capital and largest city in France, situated on the river Seine, in northern France, at the heart of the Île-de-France region...
ian water authorities in the nineteenth century. For more information on Chalk karst, the works of the great pioneer speleologist
Speleology
Speleology is the scientific study of caves and other karst features, their make-up, structure, physical properties, history, life forms, and the processes by which they form and change over time...
A.E.Martel should be consulted.