Geology of Ireland Geology of Ireland The geology of Ireland consists of the study of the rock formations in Ireland. The island contains rocks from every age from Proterozoic to Holocene and a large variety of different rock types is represented. The basalt columns of the Giant's Causeway together with geologically significant sections of the adjacent coast have been declared a World Heritage Site. The geological detail follows the major events in Ireland's past based on the geological timescale. The oldest known Irish rock is about 1.7 billion years old and is found on Inishtrahull Island off the north coast of Ulster. Outcrops
Geological history of the Precordillera terrane range)—literally "pre-mountain range"—and applied usually to the Andes. The Precordillera is in western Argentina and can be traced by the thrust-fold belt. It is about 200 km wide, and stretches 800 km from latitude 29°S to 33°S in western Argentina, with its south end in Mendoza, through San Juan, to La Rioja in the north. The northern and southern boundaries are not precisely defined. In terms of geological regions, the northeastern boundary connects to the western Pampeanas and the Famatina ranges, and the eastern margin connects to the frontal cordillera then the Chilenia Terrace. The Early-Cambrian to Ordovician deposits of