Permo‐Triassic development from Ireland to Norway: basin architecture and regional controls

Abstract

Extensive occurrences of Permo‐Triassic strata are preserved along the Northwest European Atlantic margin. Seismic reflection and well data are used to describe large‐scale Permo‐Triassic basin geometries along a swath of the continental shelf more than 2000 km long extending from the Irish to the mid‐Norwegian sectors. Successions in the Celtic Sea, the flanks of the Irish Rockall Basin, basins west and north of Scotland, and the Trøndelag and Horda platforms west of Norway are described. The large‐scale Permo‐Triassic depositional geometries commonly represent erosional remnants of larger basins modified by later rifting episodes, uplift, inversion and continental breakup. However, the interpreted geometries reveal spatial and temporal differences in rifting style. The basins developed above a complex mosaic of petrologically heterogeneous crustal terranes with inherited crustal fabrics, which had a significant impact on the depositional basin geometries. Small Permian basins with growth faulting developed in the southern Celtic Sea region. Extensive, uniformly thick Triassic strata are characteristic of the wide rift basins in the southeastern Rockall Basin and northwest of the Solan Bank High. Thick, fault‐controlled basins developed in the Horda and Trøndelag platform regions. The main controls on Permo‐Triassic basin architecture are (a) crustal thickness and composition, which determined the development of narrow or wide rift basin geometries, (b) inherited Variscan, Caledonian and Precambrian basement structures and (c) pre‐rift palaeotopography. Copyright © 2009 John Wiley & Sons, Ltd.

Kinematic Evolution of the Southern North Atlantic: Implications for the Formation of Hyperextended Rift Systems

“…Crustal thickness maps and profile extractions from these maps highlight clearly the location of this structural marker. Even if most of the extension and thinning occur between the two conjugate necking lines, the southern North Atlantic experienced extensional deformation since Late Carboniferous‐Permian time (Stolfova & Shannon, ). Although the amount of extension is difficult to quantify accurately, we consider that it falls within the error bars/uncertainties of our model.…”

“…The Mesozoic evolution of the southern North Atlantic is highly debated; however, there is a general agreement on the plate configuration at the Triassic‐Jurassic boundary and at the first magnetic anomaly after the Cretaceous normal polarity superchron C34, which is Campanian in age (83 Ma) (Barnett‐Moore, Müller, et al, ; Vissers & Meijer, , ). Widespread diffuse Permo‐Triassic extensional events occurred in the southern North Atlantic realm, but the associated extension is limited (Leleu & Hartley, ; Stolfova & Shannon, ); therefore, we approximate the Triassic‐Jurassic boundary restoration as the full fit.…”

“…Most of the models (Jammes et al, ; Olivet, ; Sibuet, ; Vissers & Meijer, ) agree on the closure of the southern North Atlantic and on the initial Triassic plate configuration. Strictly speaking, the Triassic‐Jurassic boundary does not correspond to the onset of extensional deformation because Triassic rift basins are widespread across the central and North Atlantic realm (e.g., Jeanne d'Arc Basin, Celtic Sea, Lusitanian Basin) (see Leleu & Hartley, ; Rasmussen et al, ; Stolfova & Shannon, ; Tankard et al, ). Although the Triassic extension phase created sedimentary basins (see Leleu et al, , for a review), the overall related crustal extension is ill constrained but seems relatively limited considering the present‐day crustal thickness beneath the sedimentary basins that are not significantly reactivated during Jurassic to Cretaceous time (e.g., Celtic Sea and Western Aproaches, Figure ).…”

The beginning of the Buntsandstein cycle (Early–Middle Triassic) in the Catalan Ranges, NE Spain: Sedimentary and palaeogeographic implications

“…15 shows the aeolian dune field distribution during the Smithian-Spathian in Iberia and adjacent areas of the western Tethys, and the palaeogeographical configuration of the Catalan and neighbouring basins at that time. Aeolian dune fields were common between 10°and 30°N latitudes (McKie and Williams, 2009;Stolfová and Shannon, 2009;McKie, 2011;McKie and Shannon, 2011;Tyrrell et al, 2012), however they were disappearing southwards, towards the low Southern Hemisphere latitudes (Woods, 2005), where fluvial systems were better developed. This gradual change was also controlled by the existing topography.…”

Structural inheritance in the North Atlantic

“…Furthermore, the shelf is transected by NW-trending continental lineaments/transfer zones (Figure 9) (Rumph et al 1993;Kimbell et al 2005a;Stoker et al 2017). Some of these lineaments link to faults onshore Ireland (e.g., SHL), others are associated with COB offsets of the Hatton-Rockall shelf (e.g., SHL, ADL) or are correlated with sedimentary basins (e.g., ADL, WTL, JF), and some may have guided magmatic intrusions or be related to oceanic fractures or accommodation zones in the Iceland Basin (e.g., CL) (Kimbell et al 2005a;Naylor and Shannon 2005;Štolfová and Shannon 2009).…”