In the Netherlands, the bulk of the Miocene to lowest Pliocene sedimentary succession is currently assigned to a single lithostratigraphical unit, the Breda Formation. Although the formation was introduced over 40 years ago, the definition of its lower and upper boundaries is still problematic. Well-log correlations show that the improved lecto-stratotype for the Breda Formation in well Groote Heide partly overlaps with the additional reference section of the older Veldhoven Formation in the nearby well Broekhuizenvorst. The distinction between the Breda and the overlying Oosterhout Formation, which was mainly based on quantitative differences in glauconite and molluscs, gives rise to ongoing discussion, in particular due to the varying concentrations of glauconitic content that occur within both formations. In addition, the Breda Formation lacks a regional-scale stratigraphic framework which relates its various regionally to locally defined shallow marine to continental members. In order to resolve these issues, we performed renewed analyses of material from several archived cores. The results of archived and new dinocyst analyses were combined with lithological descriptions and wire-line log correlations of multiple wells, including the wells Groote Heide and Broekhuizenvorst. In this process, the updated dinocyst zonation of Munsterman & Brinkhuis (2004), recalibrated to the Geological Time Scale of Ogg et al. (2016), was used. To establish regionally consistent lithostratigraphic boundaries, additional data was used along a transect across the Roer Valley Graben running from its central part (well St-Michielsgestel-1) towards the southern rift shoulders (well Goirle-1). Along this transect, chronostratigraphic and lithostratigraphic analyses were integrated with well-log correlation and the analyses of seismic reflection data to constrain geometrical/structural relationships as well. The results led to the differentiation of two distinct seismic sequences distinguished by three recognisable unconformities: the Early Miocene Unconformity (EMU), the Mid-Miocene Unconformity (MMU) and the Late Miocene Unconformity (LMU). The major regional hiatus, referred to as the Mid-Miocene Unconformity, occurs intercalated within the present Breda Formation and compels subdivision of this unit into two formations, viz. the here newly established Groote Heide and the younger Diessen formations. Pending further studies, the former Breda Formation will be temporally raised in rank to the newly established Hilvarenbeek subgroup, which comprises both the Groote Heide and Diessen formations. Whereas these two sequences were already locally defined, a third sequence overlying the LMU represents two newly defined lithostratigraphical units, named the Goirle and the Tilburg members, positioned in this study at the base of the Oosterhout Formation. Besides their unique lithological characteristics, in seismic reflection profiles the Goirle and the Tilburg members stand out because of their distinct seismic facies. Use of an integrated, multidisciplinary and regional approach, an improved southern North Sea framework and more comprehensive lithostratigraphic subdivision of Neogene successions is proposed for the Netherlands, to make (cross-border) correlations more straightforward in the future.

The field of provenance analysis has seen a revival in the last decade as quantitative data-acquisition techniques continue to develop. In the 20th century, many heavy-mineral data were collected. These data were mostly used as qualitative indications for stratigraphy and provenance, and not incorporated in a quantitative provenance methodology. Even today, such data are mostly only used in classic data tables or cumulative heavy-mineral plots as a qualitative indication of variation. The main obstacle to rigorous statistical analysis is the compositional nature of these data which makes them unfit for standard multivariate statistics. To gain more information from legacy data, a straightforward workflow for quantitative analysis of compositional datasets is provided. First (1) a centred log-ratio transformation of the data is carried out to fix the constant-sum constraint and non-negativity of the compositional data. Next, (2) cluster analysis is followed by (3) principal component analysis and (4) bivariate log-ratio plots. Several (5) proxies for the effects of sorting and weathering are included to check the provenance significance of observed variations and finally a (6) spatial interpolation of a provenance proxy extracted from the dataset can be carried out. To test this methodology, available heavy-mineral data from the southern edge of the Miocene North Sea Basin are analysed. The results are compared with available information from literature and are used to gain improved insight into Miocene sediment input variations in the study area.

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Stratigraphic analysis of cored and geophysically logged boreholes in the Kasterlee-Geel-Retie-Mol-Dessel area of the Belgian Campine has established the presence of two lithostratigraphic units between the classical Diest and Mol Formations, geometrically related to the type Kasterlee Sand occurring west of the Kasterlee village and the study area. A lower ‘clayey Kasterlee’ unit, equivalent to the lithology occurring at the top of the Beerzel and Heist-op-den-Berg hills, systematically occurs to the east of the Kasterlee village. An overlying unit has a pale colour making it lithostratigraphically comparable to Mol Sand although its fine grain size, traces of glauconite and geometrical position have traditionally led stratigraphers to consider it as a lateral variety of the type Kasterlee Sand; it has been named the ‘lower Mol’ or ‘Kasterlee-sensu-Gulinck’ unit in this study. In the present analysis, the greenish glauconitic Kasterlee Sand in its hilly stratotype area evolves eastwards into the lower ‘clayey Kasterlee’ unit and possibly also into an overlying ‘lower Mol’ or ‘Kasterlee-sensu-Gulinck’ unit, although it is equally possible that the latter unit has an erosive contact and therefore is stratigraphically slightly younger than the type Kasterlee Sand west of the Kasterlee village. A lateral extension of this detailed stratigraphic succession into the faulted zone of east Limburg is proposed.

The stratigraphy, sedimentology and paleogeography of the lower and middle Miocene Berchem and Bolderberg Formations from northern Belgium have been extensively studied during the last decades, a.o. in the framework of doctoral research, as parts of subsurface mapping and interregional geological correlation initiatives by governmental organizations. The last formal stratigraphical revision on formation level, however, almost dates from two decades ago, notwithstanding the fact that a wealth of new data has become available. A compilation and assessment of the stratigraphical data of the lower and middle Miocene has been carried out and a refined stratigraphical framework—based on dinoflagellate cyst stratigraphy—is presented. Recommendations for the National Commission for Stratigraphy of Belgium are proposed. A new member, the Molenbeersel member, is proposed for the glauconite-bearing silts and fine sands in the upper part of the Bolderberg Formation in the Roer Valley Graben.