The Distribution of Aptian Sandstones in the Central and Northern North Sea (Uk Sectors): A Lowstand Systems Tract “Play”

Abstract

This paper discusses the lithostratigraphy, bio stratigraphy and depositional sequence stratigraphy of the sandstones within the late Aptian Sola Formation in the Central and Northern North Sea (UK sector). The genesis and age of these sandstones are discussed and three depositional models are proposed. These sandstones have reservoir potential, and an exploration strategy is discussed in part two of this paper (referred to hereafter as Crittenden et al., in press). We interpret these sandstones to be the product of mass‐flow sedimentary processes initiated by a tectonically‐induced major fall in relative sea‐level during the late Aptian. Sediments, including sands, which accumulated on the shelfal and shelf/slope break areas of the North Sea during the early Aptian relative sea‐level high were subsequently reworked and eroded; together with the products of erosion of the bedrock geology, they were transported down‐slope into deeper‐water basinal depocentres during the late Aptian.

Tectonostratigraphic framework and depositional history of the Cretaceous–Danian succession of the Danish Central Graben (North Sea) – new light on a mature area

“…We support the interpretation of this regional sedimentation pattern as the result of an earliest late Aptian drop in relative sea level, which led to the isolation of intrashelf basins (restricted environments, faunal change), and the mobilization and deposition of coarse siliciclastics into the basinal lows (Crittenden et al 1997(Crittenden et al , 1998. A late Aptian, high-amplitude, long-lasting sea-level drop has also been documented in a number of sites in the Neotethys domain, such as the Arabian Plate (van Buchem et al 2010;Maurer et al 2013), Spain (Bover-Arnal et al 2014) and Siberia (Medvedev et al 2011).…”

“…Literature references -Danish sector: Larsen (1966), Jensen et al (1986) and this study; the UK: Deegan & Scull (1977), Johnson & Lott (1993) and Copestake et al (2003); Norway: Isaksen & Tonstad (1989) and the Ran sandstone Member: see e.g. Crittenden et al 1997Crittenden et al , 1998Ainsworth et al 2000;Copestake et al 2003). These sandstone deposits are locally associated with incised channel systems and non-deposition on the basin highs.…”

“…For the Lower Cretaceous of the North Sea Basin, a number of sequence schemes have been proposed over the years, most of which were established for a particular region (e.g. Crittenden et al 1997;Ineson et al 1997;Jeremiah 2000;Jeremiah et al 2010). Here we compare our subdivisions in tectonostratigraphic phases and sequences to the scheme proposed by Copestake et al (2003), which was intended to provide a framework for the Northern North Sea Basin, and the study by Jeremiah et al (2010), which deals with the southern, siliciclastic margin of the North Sea Basin in The Netherlands.…”

“…However, in the UK and Norwegian sectors, this play contains a number of oil fields in the Britannia, Captain, Kopervik and Ran sandstones (e.g. Crittenden et al 1997Crittenden et al , 1998 (Fig. 19).…”

Deep incision in an Aptian carbonate succession indicates major sea‐level fall in the Cretaceous

“…The transgressive infill of Depositional Sequence C is of latest Aptian age, such as the siliciclastic backfills observed in Qatar (Raven et al, 2010) and western Siberia (Medvedev et al, 2011). In addition, Late Aptian sea-level falls of up to tens of metres in magnitude have been recognized in Venezuela (Jacquin et al, 1993), the western Pacific guyots (R€ ohl & Ogg, 1998), the Adriatic Platform in Croatia (Husinec & Jelaska, 2006), the North Sea (Crittenden et al, 1997), Yemen (Morrison et al, 1997) and the Russian Platform (Sahagian et al, 1996;Zorian & Ruban, 2012). Palaeogeographic maps showing the location of sites with evidence of significant relative sea-level falls of Aptian age are found in Rameil et al (2012) and Maurer et al (2013).…”