Abstract
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.
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.
Original language | English |
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Article number | 102975 |
Number of pages | 32 |
Journal | Earth Science Reviews |
Volume | 206 |
Early online date | 18 Oct 2019 |
DOIs | |
Publication status | Published - Jul 2020 |
Bibliographical note
Christian Schiffer’s Carlsberg Foundation postdoctoral fellowship was held at Durham University, where the series of North Atlantic workshops that led to this special ESR volume were planned and held. Thomas Phillip’s postdoctoral fellowship at Durham University is funded by the Leverhulme Foundation. Martyn Stoker gratefully acknowledges the award of Visiting Research Fellow at the Australian School of Petroleum. The authors thank all participants of the North Atlantic workshop series. Four anonymous reviewers and the handling editor are thanked for constructive and useful comments, and John Kipps (Equinor) for help with some of the figures.Keywords
- North Atlantic
- Wilson Cycle
- continental breakup
- lithosphere
- magmatism
- plate tectonics
- reactivation
- rifting
- structural inheritance
- INFLUENCE FAULT DEVELOPMENT
- OROGENIC EXTENSIONAL COLLAPSE
- PREEXISTING BASEMENT WEAKNESS
- SORGENFREI-TORNQUIST ZONE
- FAROE-SHETLAND BASIN
- SOUTHWESTERN BARENTS SEA
- CRUST-MANTLE TRANSITION
- EAST GREENLAND CALEDONIDES
- CONTINENT-CONTINENT COLLISION
- JAN-MAYEN MICROCONTINENT