Barns Batch Spinney () is a 0.06-

hectare The hectare (; SI symbol: ha) is a non-SI metric unit of area equal to a square with 100- metre sides (1 hm2), or 10,000 m2, and is primarily used in the measurement of land. There are 100 hectares in one square kilometre. An acre is ...

geological Site of Special Scientific Interest near the village of Dundry,

North Somerset North Somerset is a unitary district in Somerset, South West England. Whilst its area covers part of the ceremonial county of Somerset, it is administered independently of the non-metropolitan county. Its administrative headquarters is in the ...

, notified in 1987. The

English Nature English Nature was the United Kingdom government agency that promoted the conservation of wildlife, geology and wild places throughout England between 1990 and 2006. It was a non-departmental public body funded by the Department for Environmen ...

citation says that Barns Batch Spinney is important because of the exposures which it provides of the lower part of the classic Inferior Oolite

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

sequence of the Dundry area. It shows rocks lying stratigraphically below the Middle and Upper Inferior Oolite Limestones seen at Dundry Main Road South Quarry. The geology at this site provides a section spanning the division of the Middle Jurassic known as the

Aalenian The Aalenian () is a subdivision of the Middle Jurassic Epoch/Series of the geologic timescale that extends from about 174.1 Ma to about 170.3 Ma (million years ago). It was preceded by the Toarcian and succeeded by the Bajocian. Stratigraphi ...

and

Bajocian In the geologic timescale, the Bajocian is an age and stage in the Middle Jurassic. It lasted from approximately 170.3 Ma to around 168.3 Ma (million years ago). The Bajocian Age succeeds the Aalenian Age and precedes the Bathonian Age. Stra ...

Stages and a sequence of rocks placed in the subdivision known as the discites zone, named after the characteristic fossil ammonite

Hyperlioceras discites ''Hyperlioceras'' is an extinct genus of cephalopod included in the ammonitid family Graphoceratidae that lived during the Bajocian stage of the Middle Jurassic. The type species is ''Hyperlioceras discites'' (Waagen, 18567) Morphology The she ...

. This is one of the thickest sequences in Britain and may be used as the basis for defining these new subzones.

References

External links

Barns Batch Spinney from GCR database
{{Authority control Bath and North East Somerset Mendip Hills Sites of Special Scientific Interest in Avon Sites of Special Scientific Interest notified in 1987