The role of structural inheritance in the development of high-displacement crustal faults in the necking domain of rifted margins: The Klakk Fault Complex, Frøya High, offshore mid-Norway

Supradetachment basins in necking domains of rifted margins: Insights from the Norwegian Sea

“…32 km long and 1.2 km thick at the MTFC (Figures 5-7). Muñoz-Barrera et al (2020) identify a good match between the geometry of the shear zone and the gravity anomaly map on the Frøya High. In the location of the supradetachment basin studied here, the gravity anomaly map shows a semi-elliptic geometry with values of 10-30 mGal between the Frøya and Gossa Highs (Figure 4b).…”

“…The MTFC began with sinistral transtensional movements during the Devonian (Braathen et al, 2000), and followed by reactivation with normal to dextral transtensional movements during the Triassic, Jurassic and Late Cretaceous-Cenozoic (Mørk & Johnsen, 2005;Mørk & Stiberg, 2003;Redfield et al, 2005;Sommaruga & Bøe, 2002). The high displacement of the segments that compose the Klakk FC and MTFC produced continental margin core complexes on the Gossa High and the north-western part of the central structural salient on the Frøya High (Muñoz-Barrera et al, 2020;.…”

“…Inheritance structures such as shear zones, faults and lithology controlled the evolution of the margin during the first two rift deformation phases, i.e., the "stretching" and "thinning" phases (sensu Peron-Pinvidic et al, 2013), in the Norwegian margin (e.g., Mjelde et al, 2009Mjelde et al, , 2013Muñoz-Barrera et al, 2020;Osmundsen et al, 2005Osmundsen et al, , 2021Péron-Pinvidic et al, 2020;Zastrozhnov et al, 2018). In this paper, we use the terms of stretching, thinning, hyperextension-exhumation phases defined by Péron-Pinvidic et al (2013).…”

Low‐Angle Normal Faults on the NW Shelf of Australia: Implications for Late Paleozoic Rifting

“…In this paper, we use the terminology of "proximal" and "necking" domains based on the change in crustal thickness, as defined by Peron-Pinvidic et al (2013) (Figure 1b). The proximal and necking domains are now recognised as key elements of continental margin architecture that relay extension from areas of limited stretching to areas of significant thinning as manifested by a rapid change in crustal thickness from 30 to 10 km (McClay & Hammerstein, 2020;Muñoz-Barrera et al, 2020Peron-Pinvidic et al, 2013).…”

“…These indicators are not observed on the seismic data, which, in contrast, exhibits a dome-shaped reflection package in the central domain. An alternative interpretation of the high-amplitude reflectors is that they may represent the continuation of the Mermaid fault at depth, which is commonly a mylonitic shear zone (Brogi et al, 2003(Brogi et al, , 2005Gans et al, 1985;Lister & Davis, 1989;Muñoz-Barrera et al, 2020;Phillips et al, 2016). The presence of a dome-shaped mylonitic shear zone below a low-angle normal fault on the Mermaid Nose iss highly suggestive of a metamorphic core complex (Whitney et al, 2013).…”