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Evidence for Cenozoic tectonic deformation in SE Ireland and near offshore.

By M.J.M. Cunningham, W.E.A. Phillips and A.L. Densmore


An integrated study of topography, bathymetry, high-resolution aeromagnetic data, and structural observations demonstrates significant Cenozoic fault activity in SE Ireland. Tectonically generated knickpoints and reddened fault breccias along topographic escarpments that are underlain by greywacke bedrock and trend oblique to the regional Caledonian strike provide evidence for fault displacement. Near-offshore faults with similar geometry produce present-day bathymetric scarps and localized tectonic topography in the inverted Kish Bank Basin. The integration of offshore high resolution aeromagnetic data and structural interpretation of the Kish Bank Basin provides evidence for dextral transtension on NNW trending faults and sinistral transpression on ENE trending faults bounding a lower Paleozoic to Carboniferous basement block. These faults correlate onshore with previously recognized Caledonian faults producing topographic offsets and surface uplift. To the north, offshore structures can be traced onshore and cut exposures of the Caledonian Leinster Granite. Structural analysis of these outcrops indicates post-Variscan deformation. A major fault on the NW margin of the batholith cuts a major erosion surface developed on Carboniferous carbonate rocks, and nonmarine Miocene deposits are preserved above this surface. Fault kinematics provide evidence of two paleostress systems: (1) NW-SE σ1, subvertical σ2 and NE-SW σ3 followed by (2) a clockwise swing of σ1 to NNW-SSE. Timing of deformation in both stress systems is probably post-Oligocene age. The mechanism driving this deformation is likely ridge-push. Much is already known about Cenozoic tectonics and exhumation from offshore basins. This study shows that onshore Ireland has also been affected by significant tectonic activity and exhumation during the Cenozoic

Publisher: American Geophysical Union
Year: 2004
DOI identifier: 10.1029/2003TC001597
OAI identifier:

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  12. (1980). Major transverse and other linears in the Leinster Granite,
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  16. (1987). The Goban Spur exploration in a deep water frontier basin, in Petroleum Geology of North West Europe,
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  18. (1989). Thermal maturation levels in the Devonian and Carboniferous rocks in Ireland,
  19. (2001). Understanding Irish landscape evolution: Pollen assemblages from Neogene and Pleistocene palaeosurfaces in western Ireland,
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