Conesby (Yorkshire East) Quarry

Site of Special Scientific Interest · 53.6220, -0.6363

Also within

Lincolnshire County

Condition (Natural England)

Unfavourable No Change (1)
UnitFeatureConditionArea (ha)Assessed
SE902147 Unfavourable No Change 0.92 2010-08-12

Geology & landscape

Geological Period: Quaternary · Rock Type: Ironstone, Mudstone

Description

Description This site is one of the last remaining exposures of Frodingham Ironstone and has yielded the richest known faunas from that unit. Bivalves are abundant and well preserved echinoderms also occur. Of particular international importance however, are the well preserved ammonite faunas indicating the Stellare and Denotatus subzones of the Upper Sinemurian. These faunas indicate several faunal 'Horizons' effectively sub zones including the blakei Horizon a key reference level for European Upper Sinemurian correlations. Conesby is one of the only two localities in Britain where this fauna is well documented. Sedimentologically and palaeoecologically, Conesby is important to research on the genesis of the economically important Frodingham Ironstone. Stratigraphically and taxonomically it is a key site for studies of European Sinemurian ammonite and bivalve faunas. Overlying the Frodingham Ironstone is a sequence of mudrocks of the Upper Sinemurian age, the Coleby Mudstone formation. These are in turn capped by wind blown sands of Pleistocene age Cover Sands.