The BGS Lexicon of Named Rock Units — Result Details

Red Arch Formation

Computer Code: REDA Preferred Map Code: REDA
Status Code: Full
Age range: Early Triassic Epoch (TE) — Early Triassic Epoch (TE)
Lithological Description: Breccio-conglomerate, reddish pink, pebble to boulder sized angular to well rounded clasts of metamorphic lithologies, matrix supported, and sandstones, reddish orange, fine-to very coarse-grained; laminated reddish purple and green mudstones at top.
Definition of Lower Boundary: The highest unconformity recognised in the former Red Arch Formation in the coastal section south of Cushendall opposite the cliff caves at the Red Arch.
Definition of Upper Boundary: Conformable transition into sandstone-dominated succession of the Sherwood Sandstone Group.
Thickness: 0-166m (0-545ft)
Geographical Limits: Coastal sections in northeast Co Antrim between the Red Arch,south of Cushendall,the north side of Red Bay at Waterfoot and the north side of Glenariff.
Parent Unit: Sherwood Sandstone Group (SSG)
Previous Name(s): Red Arch Formation (REDA)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Reference Section  Commences at the highest unconformity recognised in the former Red Arch Formation in the coastal section south of Cushendall opposite the cliff caves at the Red Arch and extends from the north side of Red Bay at Waterfoot along the north side of Glenariff. Irish Grid 
Reference(s):
Simon, J B. 1984. Sedimentation of a small complex alluvial fan of possible Upper Old Red Sandstone age, Northeast County Antrim. Irish Journal of Earth Sciences 6, 109-119. 
Turner, P, Shelton, R, Ruffell, A and Pugh, J. 2000. Palaeomagnetic constraints on the age of the Red Arch Formation and associated sandstone dykes (Northern Ireland). Journal of the Geological Society, London, 157, 317-325. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable