Brimble Pit and Cross Swallet Basins
Encyclopedia
Brimble Pit and Cross Swallet Basins is a 154.3 hectare
(381.3 acre) geological Site of Special Scientific Interest between Wookey Hole
and Priddy
in the Mendip Hills
, Somerset
, notified in 1987.
The site covers the two adjacent karstic basins draining into Brimble Pit and Cross Swallet. These are the two best defined of the belt of large shallow closed depressions which account for the total topography
along the southern edge of the Mendip Hills. The Brimble Pit depression has a large old lake sediment floor now pitted with sinkholes, while the Cross Swallet Basin feeds to a single active sinkhole
around which are well preserved terraces of both rock and sediment
. Both depressions have marginal cols feeding to overflow channels now permanently dry. The site also contains important Pleistocene
/Quaternary mammal
remains within
sediments infilling former caverns exposed on the north east face of Westbury Quarry.
The swallet was excavated by William Stanton between 1991 & 1992 for spelaeological purposes. However, archaeological material was discovered, leading Stanton to separate the deposits he was removing and examine them for archaeological material, which included 42 sherds of Grooved Ware
pottery and a polished greenstone
axehead.
The area is included in the Cook's Fields Nature Reserve run by the Somerset Wildlife Trust
.
Hectare
The hectare is a metric unit of area defined as 10,000 square metres , and primarily used in the measurement of land. In 1795, when the metric system was introduced, the are was defined as being 100 square metres and the hectare was thus 100 ares or 1/100 km2...
(381.3 acre) geological Site of Special Scientific Interest between Wookey Hole
Wookey Hole
Wookey Hole Caves is a show cave and tourist attraction in the village of Wookey Hole on the southern edge of the Mendip Hills near Wells in Somerset, England.Wookey Hole cave was formed through erosion of the limestone hills by the River Axe...
and Priddy
Priddy
Priddy is a village in Somerset, England in the Mendip Hills, close to East Harptree and north-west of Wells. It is in the local government district of Mendip....
in the Mendip Hills
Mendip Hills
The Mendip Hills is a range of limestone hills to the south of Bristol and Bath in Somerset, England. Running east to west between Weston-super-Mare and Frome, the hills overlook the Somerset Levels to the south and the Avon Valley to the north...
, Somerset
Somerset
The ceremonial and non-metropolitan county of Somerset in South West England borders Bristol and Gloucestershire to the north, Wiltshire to the east, Dorset to the south-east, and Devon to the south-west. It is partly bounded to the north and west by the Bristol Channel and the estuary of the...
, notified in 1987.
The site covers the two adjacent karstic basins draining into Brimble Pit and Cross Swallet. These are the two best defined of the belt of large shallow closed depressions which account for the total topography
Topography
Topography is the study of Earth's surface shape and features or those ofplanets, moons, and asteroids...
along the southern edge of the Mendip Hills. The Brimble Pit depression has a large old lake sediment floor now pitted with sinkholes, while the Cross Swallet Basin feeds to a single active sinkhole
Sinkhole
A sinkhole, also known as a sink, shake hole, swallow hole, swallet, doline or cenote, is a natural depression or hole in the Earth's surface caused by karst processes — the chemical dissolution of carbonate rocks or suffosion processes for example in sandstone...
around which are well preserved terraces of both rock and 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....
. Both depressions have marginal cols feeding to overflow channels now permanently dry. The site also contains important Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....
/Quaternary mammal
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
remains within
sediments infilling former caverns exposed on the north east face of Westbury Quarry.
The swallet was excavated by William Stanton between 1991 & 1992 for spelaeological purposes. However, archaeological material was discovered, leading Stanton to separate the deposits he was removing and examine them for archaeological material, which included 42 sherds of Grooved Ware
Grooved ware
Grooved ware is the name given to a pottery style of the British Neolithic. Its manufacturers are sometimes known as the Grooved ware people. Unlike the later Beaker ware, Grooved culture was not an import from the continent but seems to have developed in Orkney, early in the 3rd millennium BC, but...
pottery and a polished greenstone
Greenstone (archaeology)
Greenstone is a common generic term for valuable, green-hued minerals and metamorphosed igneous rocks and stones, that were used in the fashioning of hardstone carvings such as jewelry, statuettes, ritual tools, and various other artefacts in early cultures...
axehead.
The area is included in the Cook's Fields Nature Reserve run by the Somerset Wildlife Trust
Somerset Wildlife Trust
Somerset Wildlife Trust is a wildlife trust covering the county of Somerset, England.The trust, which was established in 1964, aims to safeguard the county's wildlife and wild places for this and future generations and manages almost 80 nature reserves. Examples include Fyne Court, Westhay Moor,...
.