Review of hydrocarbon potential in East Denmark following 30 years of exploration activities

Abstract

Between 1993 and 2017, Denmark was one of the largest oil exporting countries in Europe having gained this position from its share in the highly prolific Danish Central Graben. However, outside the Central Graben few prospects have been adequately mapped, due to a lack of data in these socalled ‘white areas.’ As such, their potential for hydrocarbon accumulation remains uncertain. This paper presents an update of the prospect and play types in this area outside the Danish Central Graben, east of 6°15´E longitude (Fig. 1), based on results from the last 30 years of exploration activities. The paper is part of a resource assessment made by the Geological Survey of Denmark and Greenland (GEUS) to the Danish Energy Agency (Schovsbo & Jakobsen 2017) and is an update of a former review of the area made in 1987 (Thomsen et al. 1987). The succeeding exploration efforts have not changed the overall low expectation for the play types in the area. Here, we show that an uncertain resource is associated with both the Zechstein carbonate play in the North German Basin and the Upper Triassic – Lower Jurassic sandstone and lower Palaeozoic shale gas plays in northern Jylland. However, questions remain as to the source of hydrocarbons in the western offshore area. Specifically, we are unable to confirm (or refute) whether these structures are sourced via long-distance migration of hydrocarbons from the Danish Central Graben.

Graptolites as fossil geo-thermometers and source material of hydrocarbons: An overview of four decades of progress

“…25), representing only a minor part of the original huge deposition area that its maximum at the Lower Ordovician may have extended for more than 800 000 km 2 (Schovsbo et al, 2018). Thermogenic gas trapped in the Alum Shales has been explored in Denmark (Schovsbo and Jakobsen, 2019) and Sweden (Pool et al, 2012) (Table 4). In Denmark and Sweden, a considerable resource has been estimated by the U.S. Geological Survey (mean = 67 × 10 9 m 3 gas; Gautier et al, 2013) and by the European Geological Surveys (Zijp et al, 2017) to be present mostly in the Cambrian (Miaolingian) to Ordovician (Tremadocian) Alum Shale Formation.…”

Hydrocarbon generation modelling in the Permian and Triassic strata of the Polish Basin: implications for hydrocarbon potential assessment

“…Whereas, in the Paris Ba sin, the Up per Tri as sic car bon ate-clay de pos its can also be an ef fec tive source rock (Cornford, 1998). Mi gra tion in the North Sea Ba sin was rel a tively short, lim ited to drain age zones of local struc tures (Cornford, 1998;Pletsch et al, 2010;Petersen and Hertle, 2018;Schovsbo and Jakobsen, 2019).…”

“…This geo graph ical pat tern is due to the geo log i cal evolu tion of the SPB area. In par tic u lar, the ex tent of rift sys tems (e.g., the Cen tral Graben and as so ci ated Ju ras sic source rocks pres ent in a lim ited area), as well as tec tonic in ver sion, source-rock pres ence and charge tim ing in flu enced on the occur rence of oil and gas fields (Cornford, 1998;Pletsch et al, 2010;Petersen and Hertle, 2018;Schovsbo and Jakobsen, 2019;Underhill and Rich ard son, 2022). How ever, fur ther hydro car bon dis cov er ies in the Me so zoic strata, for ex am ple, in the Pol ish Ba sin and other less ex plored bas ins are still pos sible (e.g., Krzywiec et al, 2017a;Kilhams et al, 2018b;Kortekaas et al, 2018).…”