Coaley Wood Quarries

Site of Special Scientific Interest · 51.6938, -2.3107

Condition (Natural England)

Favourable (1)
UnitFeatureConditionArea (ha)Assessed
ST786994 Favourable 4.96 2011-08-11

Geology & landscape

Geological Period: Jurassic · Rock Type: Sandstone

Description

Area, 4.85 ha. 12 ac. Description This has long been a famous geological site for the abundant fossils of Lower Jurassic age which occur here, in the stratum known as the 'Cephalopod bed'. One particular horizonis especially noted for the ammonites it contains, which are of great value in accurately dating the rocks. The ammonites found here indicate that the strata are of early striatulum Subzone age. The sunken lane cuttings provide valuable exposures of the underlying Cotswold Sand Formation. Within this formation, a thin, isolated sandstone layer contains what are elsewhere very rare ammonites, known as Haugia, which again give an accurate indication of the age of these rocks; in this case they belong to the variabilis subzone, slightly older than the Cephalopod bed.