Tectonic controls on Upper Jurassic to Lower Cretaceous reservoir architecture in the Jeanne d’Arc Basin, with some comparisons from the Porcupine and Moray Firth Basins

Abstract

Seismic, wireline log and core data from three geographically separate basins in the North Atlantic provide an understanding of the regional dynamics of the basin system, and quantify the sedimentary geometry response to a composite rift episode. The response to the Late Cimmerian rift episode in the Jeanne d’Arc, Porcupine and Moray Firth Basins is broadly comparable, with an initial episode of clastic reservoir facies deposition associated with active growth faulting. This was followed by a mid-rift period where subsidence outstripped sedimentation, resulting in organic-rich source rocks and culminating in a mappable maximum flooding surface. During the final phase of the rift episode, the decrease in subsidence rate resulted in the return of reservoir-quality clastics. The reservoir-scale response to the initial rifting is illustrated in cored sequences from the Jeanne d’Arc Basin. These indicate the development of axial and lateral sandy and conglomeratic braided fluvial and alluvial fan systems, with periods of muddy lacustrine deposition. Pedogenic surfaces offer much potential for detailed correlation and the analysis of sandbody geometry. The onset of anoxic conditions conducive to source rock deposition during the mid-rift phase of Late Cimmerian tectonism, and the preferential development of reservoir facies at the base and top of syn-rift sediment fill, are characteristics of considerable importance to exploration of the North Atlantic borderland rift basins.

Crustal thinning, mantle exhumation and serpentinization in the Porcupine Basin, offshore Ireland: evidence from wide-angle seismic data

“…1). Its present shape and major structure are generally thought to have formed during a major episode of lithospheric stretching in Jurassic times, with other, less pronounced rift episodes in the Permo-Triassic and Early Cretaceous (Shannon 1991;Tate 1993;Sinclair et al 1994;Shannon et al 1995). Inherited tectonic fabrics from Variscan, Caledonian and older orogenic cycles had a strong influence on the pattern and scale of Mesozoic sedimentary basin development in this part of the North Atlantic.…”

Comparison of lithosphere structure across the Orphan Basin–Flemish Cap and Irish Atlantic conjugate continental margins from constrained 3D gravity inversions

“…2), these basins appear to have formed through differential stretching of the crust, and exhumation of serpentinized mantle has been interpreted beneath both basins O'Reilly et al 1996O'Reilly et al , 2006Reston et al 2004). Although a few studies have attempted to compare and connect these and other structures and basins from the Irish margin across to the conjugate Newfoundland margin (Sinclair et al 1994;Shannon et al 1995), the main focus of previous bridging studies has been on the Goban Spur and its conjugate margin of Flemish Cap Peddy et al 1989;Horsefield et al 1994;Bullock & Minshull 2005).…”

Jurassic non-marine source rocks and oils of the Porcupine Basin and other North Atlantic margin basins

“…1) shares a similar Jurassic tectonic evolution and petroleum system to the Porcupine Basin (Sinclair et al 1994;Shannon et al 1995;Sinclair & Riley 1995: Williams et al 1999Fig. 3).…”

“…Where penetrated these formations are more oxidized, terrigenous-rich marginal facies which might improve in quality towards the basin centres, although von der Dick (1989) does not comment on the degree of marine or lacustrine geochemical signature in these formations. Shannon et al (1995), however, document a series of rhythmically laminated lacustrine shales from the Terra Nova Member, K-18 Shale, and Beothuk Member of the Jeanne d'Arc Formation, which appear to be very similar in nature to the algal lacustrine oil-prone shales of the Porcupine Basin. A possible early Tertiary contributor has also been speculated, although the lack of oleanane (a Tertiary age diagnostic biomarker) may preclude a Tertiary contributor (von der Dick 1989; von der Dick et al 1989;Fowler & Brooks 1990).…”

“…Porcupine Basin tectono-stratigraphy and petroleum systems summary, with comparative Jeanne d'Arc Basin stratigraphy (the latter taken fromShannon et al 1995).…”