Belshaws Quarry ASSI

Belshaw’s Quarry is of importance because of its geology. It is one of a series of sites that describes the Clay-with-flints (CwF), a unique deposit whose exposure is mostly confined to the margins of the Antrim Plateau. Stratigraphically, at most localities, the deposit occurs between older white chalk of the Late Cretaceous Ulster White Limestone Formation (83 to 72 million years old) below, and lava flows of younger black basalt of the early Palaeogene Antrim Lava Group (63 to 60 million years old) above. The period of time within which the CwF formed spans about 10 million years of the Late Cretaceous and Early Palaeogene.