Published online by Cambridge University Press: 01 May 2009
Ooids and grapestones from some parts of the Corallian Beds (Oxfordian) contain encrustations of the foraminiferid Nubeculinella. Encrusted layers within ooids clearly reveal lengthy periods when the grains were stationary and not accreting carbonate laminae. It seems likely that during colonisation by the foraminiferids the ooids were immobilised beneath a subtidal algal mat and there are indications that the mats were sufficiently coherent to bind lumps of sediment together during disruption by burrowing organisms.