The gravity signature of Caledonian and Variscan tectonics in Ireland

Abstract A map of the vertical gradient of the Bouguer anomaly for Ireland has been produced and used to define crustal fabrics related to tectonic development. Several sets of linear features can be identified. Lineaments trending NE to NNE can be correlated with mapped Caledonian trending fault systems and shear zones and related to an overall Caledonian plate tectonic setting. Gravity trends in the south of Ireland are clearly aligned in an E-W (‘Variscan’) direction. Features which are resolved can be related to the known geological history of Ireland and placed in a regional context within the NE Atlantic and Europe using the marine free-air anomalies derived from satellite altimetry.