Structural inheritance in the North Atlantic

• Published in: Earth-Science Reviews
• Main Authors: Schiffer, Christian, Doré, Anthony G., Foulger, Gillian R., Franke, Dieter, Geoffroy, Laurent, Gernigon, Laurent, Holdsworth, Bob, Kusznir, Nick, Lundin, Erik, Mccaffrey, Ken, Peace, Alexander L., Petersen, Kenni D., Phillips, Thomas B., Stephenson, Randell, Stoker, Martyn S., Welford, J. Kim
• Other Authors: Laboratoire Géosciences Océan (LGO), Université de Bretagne Sud (UBS)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2020
• Subjects: CNAR; Circum-North Atlantic Region; COB; Continent Ocean Boundary; COT; Continent Ocean Transition; GGF; Great Glen Fault; GIFR; Greenland-Iceland-Faroe Ridge; GIR; Greenland-Iceland Ridge; HBF; Highland Boundary Fault; HFZ; Hardangerfjord Fault Zone; HVLC/HVLCB; High velocity lower crust/ High velocity lower crustal body; IFR; Iceland-Faroe Ridge; JMMC; Jan Mayen Microplate Complex; Moho; Mohorovičić Discontinuity/Crust-Mantle boundary; MTTC; Møre-Trøndelag Fault Complex; NAIP; North Atlantic Igneous Province; SDR; Seaward Dipping Reflector; TZ; Tornquist Zone; TIB; Trans-Scandinavian Igneous Belt; WBF; Walls Boundary Fault; [SDU]Sciences of the Universe [physics]; Greenland; Jan Mayen; Norway; Svalbard; Iceland; North Atlantic; North Norway
• Online Access: https://hal-insu.archives-ouvertes.fr/insu-03685641; https://doi.org/10.1016/j.earscirev.2019.102975

International audience The North Atlantic, extending from the Charlie Gibbs Fracture Zone to the north Norway-Greenland-Svalbard margins, is regarded as both a classic case of structural inheritance and an exemplar for the Wilson-cycle concept. This paper examines different aspects of structural inheritance in the Circum-North Atlantic region: 1) as a function of rejuvenation from lithospheric to crustal scales, and 2) in terms of sequential rifting and opening of the ocean and its margins, including a series of failed rift systems. We summarise and evaluate the role of fundamental lithospheric structures such as mantle fabric and composition, lower crustal inhomogeneities, orogenic belts, and major strike-slip faults during breakup. We relate these to the development and shaping of the NE Atlantic rifted margins, localisation of magmatism, and microcontinent release. We show that, although inheritance is common on multiple scales, the Wilson Cycle is at best an imperfect model for the Circum-North Atlantic region. Observations from the NE Atlantic suggest depth dependency in inheritance (surface, crust, mantle) with selective rejuvenation depending on time-scales, stress field orientations and thermal regime. Specifically, post-Caledonian reactivation to form the North Atlantic rift systems essentially followed pre-existing orogenic crustal structures, while eventual breakup reflected a change in stress field and exploitation of a deeper-seated, lithospheric-scale shear fabrics. We infer that, although collapse of an orogenic belt and eventual transition to a new ocean does occur, it is by no means inevitable.