Geological evolution of the Chalk Group in the northern Dutch North Sea: inversion, sedimentation and redeposition

Abstract

In contrast to the Norwegian and Danish sectors, where significant hydrocarbon reserves were found in chalk reservoirs, limited studies exist analysing the chalk evolution in the Dutch part of the North Sea. To provide a better understanding of this evolution, a tectono-sedimentary study of the Late Cretaceous to Early Palaeogene Chalk Group in the northern Dutch North Sea was performed, facilitated by a relatively new 3D seismic survey. Integrating seismic and biostratigraphic well data, seven chronostratigraphic units were mapped, allowing a reconstruction of intra-chalk geological events.The southwestward thickening of the Turonian sequence is interpreted to result from tilting, and the absence of Coniacian and Santonian sediments in the western part of the study area is probably the result of non-deposition. Seismic truncations show evidence of a widespread inversion phase, the timing of which differs between the structural elements. It started at the end of the Campanian followed by a second pulse during the Maastrichtian, a new finding not reported before. After subsidence during the Maastrichtian and Danian, renewed inversion and erosion occurred at the end of the Danian. Halokinesis processes resulted in thickness variations of chalk units of different ages.In summary, variations in sedimentation patterns in the northern Dutch North Sea relate to the Sub-Hercynian inversion phase during the Campanian and Maastrichtian, the Laramide inversion phase at the end of the Danian, and halokinesis processes. Additionally, the Late Cretaceous sea floor was characterized by erosion through contour bottom currents at different scales and resedimentation by slope failures.

Multiple phase rifting and subsequent inversion in the West Netherlands Basin: implications for geothermal reservoir characterization

“…In fact, a local unconformity divides the upper from the central and lower portions of this megasequence, as illustrated in figures 3 and 4. This is consistent with regional constraints, indicating that the Subhercynian inversion ceased after the Campanian ( de Jager, 2003), whereafter deposition of the chalk of megasequence 3 continued for the entire Late Cretaceous (van Balen et al, 2000;van der Voet et al, 2019).…”

The occurrence of a palaeo‐lithification front in an overpressured basin (Chalk Group)—Timing from clumped isotopes and seismic stratigraphic analysis

“…Given that most of the Chalk Group in the North Sea share a similar lithological homogeneity, we speculate that this lithification front can be observed in seismic data in the Dutch, German, Norwegian and English sectors (e.g. Arfai et al, 2014; Gennaro et al, 2013; van der Molen et al, 2005; van der Voet et al, 2019). We speculate that this marker can also be seen on onshore seismic data where burial depths of the Chalk Group have been significant (Nielsen et al, 2011).…”

Depositional architecture of the Upper Cretaceous succession in central Poland (Grudziądz-Polik area) based on regional seismic data

“…A sys tem of Up per Cre ta ceous bas ins dom i nated by pe lagic car bon ates, such as chalk, "chalk-like" lime stone, gaize (carbon ate-si li ceous rock con tain ing de tri tal quartz and sponge spicules), and opoka (car bon ates con tain ing biogenic sil ica), is well-known over ex ten sive ar eas of the East Eu ro pean Craton and the West Eu ro pean Plat form (e.g., Ziegler, 1990;Voigt et al, 2008;Vejb³k et al, 2010;Mortimore, 2011;Torsvik and Cocks, 2016). In these bas ins, a pat tern of hor i zon tal lay ers with broadly layer-cake pat terns can be an tic i pated, for the most part; in many cases, how ever, the depositional ar chi tec ture of the Up per Cre ta ceous suc ces sion is more com plex due to regional Late Cre ta ceous ba sin in ver sion and as so ci ated re ac tiva tion of salt struc tures, which led to strati graphic pinch-outs, in ci sions, and lat eral thick ness changes (e.g., Ziegler, 1990;Vejb³k and Andersen, 2002;Esmerode et al, 2007;Surlyk and Lykke-Andersen, 2007;Krzywiec et al, 2009Krzywiec et al, , 2018aGennaro et al, 2013;Larsen et al, 2014;Arfai et al, 2016;Krzywiec and Stachowska, 2016;van der Voet et al, 2018;Hübscher et al, 2019).…”