Structural Controls On Different Styles of Cenozoic Inversion in the Celtic Sea Basins, Offshore Ireland

Compressional structures developed as a result of Cenozoic inversion are well known along the north-western Atlantic passive margin but, despite their significance in North Atlantic petroleum systems, details of their mechanisms of formation remain unclear. In this study we provide examples of the style and characteristics of these inversion structures defined from regional 2D and 3D datasets within the Celtic Sea Basins in offshore Ireland. Two end-member styles of inversion are recognized: short-wavelength, elongate anticlines that occur predominantly at the margins of the Jurassic basins and long-wavelength, relatively equidimensional anticlines that occur at the centre of the basins. Based on the location and orientation of 53 inversion structures a relationship between the inversion structure type and i) basement structural fabrics, ii) basin depocentre distribution and iii) pre-inversion extensional fault orientation is established.