Holwell Quarries

Site of Special Scientific Interest · 51.2026, -2.3919

Also within

Somerset County

Condition (Natural England)

Favourable (4)
UnitFeatureConditionArea (ha)Assessed
ST723448 Favourable 1.3 2021-11-18
ST724450 Favourable 1.3 2021-11-18
ST727449 Favourable 1.3 2021-11-18
ST727450 Favourable 1.3 2021-11-18

Geology & landscape

Geological Feature: Fissure · Geological Period: Jurassic, Triassic

Description

Area, 1.29 ha. 3.19 ac. Description Holwell Quarries represent an internationally important geological locality. A comprehensive assemblage of Triassic including Rhaetic, Lower Jurassic and Middle Jurassic fissure fillings are well displayed. The Rhaetic fissure fillings have yielded the richest assemblage of vertebrate faunas known from the British Triassic. The site is famous as the site where Moore in the 1860s and later Kuhne 1939, collected specimens of Rhaetic mammals; occurrences of the highest scientific interest. Other mammals as well as abundant fish remains from the site have yet to be described. Fissure deposits have also yielded 8 or 9 genera of Reptiles, a Crocodilian, a Placodont the first record in Britain of this sub order and the dinosaurs The codontosaurus and Palaeosaurus. The Lower Jurassic fissure fillings yield ammonites and brachiopods which are important in dating these remarkable deposits. Subsidiary interest is supplied by the three dimensional 'wadi fill' of Triassic age and the regionally important sub Inferior Oolite unconformity, both of which are very well exposed in the Holwell complex.