Orphan Basin, offshore Newfoundland, Canada: Structural and tectonic framework, petroleum systems and exploration potential

Structure and rifting evolution of the northern Newfoundland Basin from Erable multichannel seismic reflection profiles across the southeastern margin of Flemish Cap

“…For the Flemish Cap‐Galicia Bank conjugate margins in region IV, the apparent fundamental asymmetry in the amount of thinning experienced by the continental crust can be attributed to several factors. First, while Flemish Cap and Galicia Bank remained connected, much of the thinning on the Newfoundland side was taking place on the other side of Flemish Cap within the Flemish Pass and Orphan Basins as Flemish Cap was rotated out of those basins (Enachescu et al 2004a,b,c; Skogseid et al 2004; Sibuet et al 2007b). Second, the localization of breakup between Flemish Cap and Galicia Bank occurred closer to the margin of Flemish Cap resulting in the present day asymmetry.…”

Tectono-stratigraphic evolution and crustal architecture of the Orphan Basin during North Atlantic rifting

“…Alternatively, brittle extension in the Orphan Basin could be only partially preserved due to important crustal flexure, uplift, and erosion (Burov and Cloetingh 1997;Burov and Poliakov 2001). Well and seismic data presented above clearly indicate sub-aerial exposure and truncation of the syn-rift successions and tilted blocks (Enachescu et al 2004;Dafoe et al 2015). The existence of discontinuous pockets of Jurassic sediments in the West Orphan Basin might even be the remnants of a more extensive Jurassic or even Late Triassic Driscoll et al 1995;Lau et al 2006;Van Avendonk et al 2009) syn-rift basin that have been eroded during the ensuing rift phase.…”

“…Chian et al 2001;Welford and Hall 2007;Lau et al 2015). The East Orphan Basin appears to be older as it contains Jurassic syn-rift sediments, while the West Orphan Basin is younger as the first syn-rift sediments are assumed to be Lower Cretaceous (Enachescu et al 2004(Enachescu et al , 2005. Despite the strong crustal thinning that is observed underneath the East and West Orphan depocentres, the Aptian-Albian continental break-up between the Newfoundland and the Irish margins occurred immediately east of the Orphan Knoll and the Flemish Cap (Figs.…”

“…Although several contributions have examined the largescale structural and crustal architecture of the Orphan Basin (e.g. Enachescu et al 2004Enachescu et al , 2005Welford et al 2012;Watremez et al 2015;Lau et al 2015), only few tried to quantify its Mesozoic syn-rift history and the driving tectonic processes (Dafoe et al 2015;Gouiza et al 2015). In this contribution, (1) we examine the stratigraphic and tectonic evolution of the Orphan Basin using exploration wells and regional seismic lines, (2) we investigate its structural and crustal architectures to quantify amounts of crustal extension versus crustal thinning during rifting, and (3) we propose tectonic processes that can explain its tectonostratigraphic evolution.…”

Conjugate margins — An oversimplification of the complex southern North Atlantic rift and spreading system?

“…Despite the research focus on the margins of the southern North Atlantic, the mechanisms driving extensional deformation in the continental domains leading to the creation of new oceanic crust, and thus passive margins, remains a topic of considerable current research interest (Nirrengarten et al, 2018;Gouiza and Paton, 2019). Current areas of research in this area include, but are not limited to: 1) timing of spatially and temporally overlapping and interacting rifting events (Gouiza et al, 2015), 2) sediment distribution, provenance and facies (Tyrrell et al, 2007), 3) timing of structural development and its relationship with hydrocarbon prospectivity (Enachescu et al, 2004), 4) the role of pre-existing structures in controlling rift evolution and margin architecture (Doré et al, 1999), and 5) the causes and consequences of rift-and breakup-related magmatism (Keen et al, 2014;Peace et al, 2018c).…”