Limestone Fossils

Location: Benburb

limestone-fossilsThere is an arched tunnel under the Ulster Canal at Benburb, where fossils are visible in the limestone rock face.  About 230m of strata belonging to the Tyrone Group are almost completely exposed in the valley of the River Blackwater at Benburb and can be divided into 4 lithostratigraphical formations which contain fossils of Asbian and Brigantian age. The deeply incised valley of the River Blackwater at Benburb extends from Milltown in the west to Benburb Bridge in the east. Rock is exposed in natural cliff sections at many points on both sides of the valley but quarrying operations, in particular on the south (Armagh) side of the valley, at and between Blackstokes Bridge (H8125 5185) and Benburb Bridge, reveal more extensive sections in the Maydown Limestone and Blackstokes Limestone formations, in particular.

Degradation and partial concealment of these quarries by new vegetation is prevalent but this problem has been counter balanced by recent renovation of the old Ulster Canal, near Milltown, in the process clearing some exposures. Fossils are abundant throughout the formation and include bivalves, bryozoa, echinoid and crinoidal debris and corals and brachiopods. The Lower Carboniferous sequence exposed at Benburb provides one of the most complete and highly fossiliferous successions of strata in south County Tyrone and County Armagh.  It is divided into four formations and constituent members.