St. Dunstan's Well Catchment () is a

Site of Special Scientific Interest A Site of Special Scientific Interest (SSSI) in Great Britain, or an Area of Special Scientific Interest (ASSI) in the Isle of Man and Northern Ireland, is a conservation designation denoting a protected area in the United Kingdom and Isle ...

, covering near

Stoke St Michael Stoke St Michael is a village and civil parish on the Mendip Hills north east of Shepton Mallet, and west of Frome, in the county of Somerset, England. History Since the 14th century the village has also been known as Stoke Lane, although t ...

in the

Mendip Hills The Mendip Hills (commonly called the Mendips) is a range of limestone hills to the south of Bristol and Bath, Somerset, Bath in Somerset, England. Running from Weston-super-Mare and the Bristol Channel in the west to the River Frome, Somerset ...

Somerset Somerset ( , ), Archaism, archaically Somersetshire ( , , ) is a Ceremonial counties of England, ceremonial county in South West England. It is bordered by the Bristol Channel, Gloucestershire, and Bristol to the north, Wiltshire to the east ...

, England. The site was notified in 1967. It is of both geological and biological significance. Formerly known as Stoke St Michael Slocker, it contains nine SSSI units consisting of rock and

calcareous grassland Calcareous grassland (or alkaline grassland) is an ecosystem associated with thin basic soil, such as that on chalk and limestone downland. There are large areas of calcareous grassland in northwestern Europe, particularly areas of southern Engla ...

Geological

St Dunstan's Well Catchment area contains a series of spectacularly-decorated caves which in total extend to about of mapped passage. The caves at Fairy Cave Quarry were formed mainly by the erosive action of water flowing beneath the water-table at considerable pressure (so called '

phreatic ''Phreatic'' is a term used in hydrology to refer to aquifers, in speleology to refer to cave passages, and in volcanology to refer to a type of volcanic eruption. Hydrology The term phreatic (the word originates from the Greek , meaning "well" ...

' development), but as the water table has fallen many of the caves now lie well above it and the system now contains a variety of cave formations (

stalagmite A stalagmite (, ; ; ) is a type of rock formation that rises from the floor of a cave due to the accumulation of material deposited on the floor from ceiling drippings. Stalagmites are typically composed of calcium carbonate, but may consist ...

stalactites A stalactite (, ; , ) is a mineral formation that hangs from the ceiling of caves, hot springs, or man-made structures such as bridges and mines. Any material that is soluble and that can be deposited as a colloid, or is in suspension, or is ca ...

and

calcite Calcite is a Carbonate minerals, carbonate mineral and the most stable Polymorphism (materials science), polymorph of calcium carbonate (CaCO3). It is a very common mineral, particularly as a component of limestone. Calcite defines hardness 3 on ...

curtains) which in their extent and preservation are amongst the best in Britain. Shatter Cave and Withyhill Cave are generally considered to be amongst the finest decorated caves in Britain in terms of their sheer abundance of pure white and translucent calcite deposits.

Biological

An area of nationally rare species-rich unimproved calcareous grassland of the Sheep's-fescue-Meadow Oat-grass type occurs in the field to the east of Stoke Lane Quarry. Small numbers of

greater horseshoe bat The greater horseshoe bat (''Rhinolophus ferrumequinum'') is an Insectivore, insectivorous bat of the genus ''Rhinolophus''. Its distribution covers Europe, Northern Africa, Central Asia and Eastern Asia. It is the largest of the horseshoe bats i ...

(''Rhinolophus ferrumequinum''),

lesser horseshoe bat The lesser horseshoe bat (''Rhinolophus hipposideros'') is a type of small European and North African insectivorous bat, related to its larger cousin, the greater horseshoe bat. As with all horseshoe bats, the species gets its name from its dist ...

(''Rhinolophus hipposideros'') and

Natterer's bat Natterer's bat (''Myotis nattereri'') is a European Vespertilionidae, vespertilionid bat with pale wings. It has brown fur tending to greyish-white on its underside. It is found across most of the continent of Europe, parts of the Near East and No ...

(''Myotis nattereri'') hibernate in the cave system.

References

{{SSSIs Somerset biological Caves of the Mendip Hills Sites of Special Scientific Interest in Somerset Geology of Somerset