Geological, geomorphological and soil maps provide important information on the substrate as well as on the past and present physical landscape. For the intensely studied Netherlands coastal plain and Rhine–Meuse delta, many such map datasets have been compiled over the last two centuries. These mapping materials comprise older and younger legacy datasets, often fragmented over regions. They have been compiled within various research traditions and by various parties, involving geologists, soil scientists, geomorphologists and landscape archaeologists. The maps and datasets summarise overwhelming amounts of underlying data accumulated over the last few centuries, and are therefore valuable for reconstructing past landscapes.

Digital-infrastructure developments have enhanced possibilities for recombining existing and new data over the last few decades, e.g. through GIS solutions such as palaeogeographical base maps, from which multiple derived map products can be generated. Integration of thematic information from various source maps and underlying data is needed to use the accumulated data diversity to its full potential and to answer applied and fundamental scientific questions. Using diverse information to compile or update maps, however, requires awareness of legacy surveying strategies and the state of knowledge at the time the original data and maps were produced. This paper reviews the soil, geological and geomorphological mapping traditions. We evaluate their products, underlying data and the reasoning behind their compilation, focusing on their use in conventional and digital palaeogeographical mapping. This helps get the most out of large quantities of legacy and modern data, a major challenge for surface and substrate digital mapping in the big-data era.

In the context of the investigation of the sedimentary and structural evolution of the Cenozoic Lower Rhine Basin, the construction of a volume-balanced kinematic model of a small faulted domain with detailed spatial information on strata and fault geometry from a set of parallel geological sections is under development. A 3D geometry model is built that allows for relative movements of blocks at fault surfaces. Rouby’s method of restoration in the map plane is used to determine horizontal displacement fields. The 3D and 3D(t) geometry models are supported by the object-oriented geometry database tool GeoToolKit for storage and retrieval of selected parts of the model using queries referring to spatial and temporal criteria, while visualization is based on key frame technique.

Assemblages of brackish and marine diatoms have been examined from Upper Paleocene-Lower Eocene strata of the Belgian Basin (Knokke well) and the Dieppe-Hampshire Basin (Saint-Josse borehole and Ailly sections). The diatoms observed are invariably preserved in pyrite as internal moulds and their siliceous skeletons are completely replaced by pyrite by epigenesis. Three major diatom assemblages have been observed which can be used to approximate the position of the recently defined Paleocene-Eocene boundary (defined by the Carbon Isotope Excursion). This isotope excursion occurs just below the strong increase in the abundance of Fenestrella antiqua and in the vicinity of the abundance peak of Coscinodiscus morsianus var. moelleri. They also allow correlations of the lithostratigraphic units of the Belgian Basin with the formations of the Dieppe-Hampshire and central North Sea Basins. For instance, investigations of diatoms recorded in the Knokke Clay Member of the Knokke well indicate that this unit corresponds to the lower units of the ‘Sparnacian facies’ of the Dieppe-Hampshire Basin and to the Sele Formation of the North Sea Basin.

Over the past decade in the Netherlands, most operators have only developed a single doublet. The learning effect from these single events is suboptimal, and operators have only been capable of developing doublets in areas with relatively low exploration risk. This ‘stand-alone’ approach can be significantly improved by a collective approach to derisk regions with similar subsurface characteristics. Such a play-based portfolio approach, which is common in the oil and gas industry, can help to accelerate the development of the geothermal industry through unlocking resource potential in areas marked by high upfront geological risk, effectively helping reduce costs for the development. The basis of the methodology is to deploy new information to the play portfolio by trading off with the risk of the first wells, resulting in a strong geological risk reduction.

The added value of the portfolio approach is demonstrated for the Netherlands in this paper through a comparison with a ‘stand-alone’ development. In the stand-alone approach, each new project will be equally risky, and therefore relatively unprofitable. In the case of a portfolio approach, all experience about the play is used optimally for derisking. In case of success, subsequent projects will have a higher chance of being successful, due to the experience gained in previous projects. Even if a project fails, this may help in increasing the probability of success for subsequent projects. For plays that are initially considered too risky for the market to start developing, the value of information (VoI) of a play-based portfolio approach will help by derisking the play to such an extent that it becomes attractive for the market to develop, even at high initial risk. It can be demonstrated for several geothermal plays in the Netherlands that by adopting the portfolio approach, the probability of a play being developed becomes higher, the number of successfully developed projects increases and the average profitability of the project will also be higher. Five more advantages are: (1) continuous improvement by integrated project development, (2) cost reduction through synergy, efficiency and standardisation, (3) optimisation of the surface heat demand and infrastructure, (4) the possibility of structural research and development (R&D) and innovation, and (5) financing advantages. The advantages reinforce each other.

A preliminary estimate of the geothermal potential of the Netherlands adopting the portfolio approach is between 90 and 275 Petajoules (PJ). For about 350 doublets being developed, producing about 70 PJ, the value of the advantage of the play-based portfolio approach is €2 billion for the three main plays: Rotliegend, Triassic and Jurassic/Cretaceous. The learning effects of synergy, efficiency and standardisation are expected to be significant.

Four recently collected tooth crowns of the rare latest Cretaceous (late Maastrichtian) durophagous mosasaur Carinodens belgicus are discussed; the first record from the Atlantic coast of North America (Maryland), and three additional in situ examples from the Maastrichtian type area in the southeast Netherlands and northeast Belgium. Also presented are an updated overview of the material recorded to date, and a discussion of the palaeobiogeographical and palaeoenvironmental distribution of the genus. Towards the end of the Cretaceous, Carinodens appears to have been successful in exploiting the margins of both the proto-Atlantic Ocean and the Tethyan Realm.

Bright white sands consisting almost exclusively of quartz (sometimes called ‘silver sands’) occur throughout the world; those in Europe commonly date from the late Paleogene and early Neogene. They have a clearly sedimentary origin, and they may have originated in various types of environments, but precise data are lacking because sedimentary research into these deposits (that have a high economic value) has been scarce. It is most likely that diagenetic processes are largely responsible for their exceptional appearance, but it is highly unlikely that all silver sands were subject to the same diagenetic conditions.

The precise origin of most of the silver sands is still enigmatic. In the case of the silver sands in the Dutch/German/Belgian border area, it appears that long-lasting in situ leaching by humic acids (resulting in an extremely low percentage of heavy minerals), in combination with differential cementation (and later partial dissolution of the cement), must be held responsible for the wide variety of the characteristics of these sands, including locally sharp boundaries with the underlying sands, lack of precipitates at the contact plane with the underlying sands, and the joint occurrence of strongly weathered and fresh specimens of the same heavy-mineral species.

A small faunule of fragmentary Hettangian (earliest Jurassic) psiloceratoid ammonites collected from dark-coloured, clay-rich sediments in a subrosion pipe at Quarry III of the Winterswijk quarry complex is described. The genera Alsatites, Saxoceras and Schlotheimia are determined by comparison to extensive literature on coeval, north German faunas. Taphonomic features are apparent indicating condensation and reworking. Despite this, the portion of the subrosion pipe sediment fill which yielded this material can be dated as middle to late Hettangian.

The presence of a magnesian vivianite (Fe2+)2.5(Mg,Mn,Ca)0.5(PO4)2·8H2O, has been identified in a soil sample from a Roman camp near Fort Vechten, The Netherlands, using a combination of Raman microscopy and scanning electron microscopy. An unsubstituted vivianite and baricite were characterised for comparative reasons. The split phosphate-stretching mode is recognised around 1115, 1062 and 1015 cm−1, while the corresponding bending modes are found around 591, 519, 471 and 422 cm−1. The substitution of Mg and Mn for Fe2+ in the crystal structure causes a shift towards higher wavenumbers compared to pure vivianite. As shown by the baričite sample substitution causes a broadening of the bands. The observed broadening however is larger than can be explained by substitution alone. The low intensity of the water bands, especially in the OH-stretching region between 2700 and 3700 cm−1 indicates that the magnesian vivianite is partially dehydrated, which explains the much larger broadening than the observed broadening caused by substitution of Mg and Mn in vivianite and baričite.

Shortly after the river Rhine enters the Netherlands, it bifurcates into three branches. A predefined, fixed discharge distribution over the bifurcation points is vital, since the dikes are designed with a predefined distribution in mind. Recent observations show that the discharge distribution that is anticipated at design discharge conditions differs from the predefined one. One of the goals of the national program Room for the River is therefore to restore the discharge distribution. To control the hydraulic processes during flood events, the construction of two adaptable spillways in the direct neighbourhood of the bifurcation points is proposed as a possible solution. The spillways are capable of maintaining the proper discharge distribution. They can also act as regulators during the construction phase of the flood managements plans of the project Room for the River. Hence, the discharge ratio and thus the water levels are such that the safety-standards are not violated. The morphological consequences are most probably very small, provided that strong erosion during flood events can be prevented and the autonomous bed degradation stays within reasonable limits.

The literature suggests that the Asquempont fault, a supposedly important reverse fault forming the limit between the Lower to lower Middle Cambrian and the Ordovician in the Sennette valley, is poorly understood. Nevertheless, this fault is commonly equated with a pronounced NW-SE-trending aeromagnetic lineament, the Asquempont lineament, and both the geometry of the Asquempont lineament and the supposed reverse movement of the Asquempont fault are used to develop large-scale tectonic models of the Brabant Massif. New outcrop observations in the Asquempont area, the “type locality” of the Asquempont fault, in combination with outcrop and borehole data from surrounding areas, show that the Asquempont fault is not an important reverse fault, but instead represents a pre-cleavage, low-angle extensional detachment. This detachment formed between the Caradoc and the timing of folding and cleavage development and is not related to the aeromagnetic Asquempont lineament. The Asquempont area also contains several relatively important, steep, post-cleavage normal faults. Apparently, these occur in a WNW-ESE-trending zone between Asquempont and Fauquez, extending westward over Quenast towards Bierghes. This zone coincides with the eastern part of the WNW-ESE-trending Nieuwpoort-Asquempont fault zone, for which, on the basis of indirect observations, previously a strike-slip movement has been proposed. Our outcrop observations question this presumed strike-slip movement. The Asquempont fault may be related to the progressive unroofing of the core of the Brabant Massif from the Silurian onwards. Possibly, other low-angle extensional detachments similar to the Asquempont fault occur in other parts of the massif. Possible candidates are the paraconformity-like contacts depicted on the most recent geological map of the Brabant Massif.

In this article we study the morphodynamics of the Slufter on the short-term (months) and long-term (years to decades). The Slufter is a small, shallow tidal inlet located on the island of Texel, the Netherlands. A narrow (tens of meters) channel connects the North Sea with a dune valley of 400 ha. This narrow channel is located in between a 400-700 m wide opening in the dunes. Approximately 80% of the basin of the Slufter is located above mean high water level and is flooded only during storms, when a threshold water level is exceeded.

Analysis of historical aerial photographs revealed that the inlet channel migrates about 100 m per year. In the 1970's it migrated to the south, while since 1980 it is migrating to the north. When the channel reached the dunes at the north side of the dune breach the channel was relocated to the south by man. The channel inside the backbarrier basin was less dynamic. It shows a gradual growth and southward migration of a meander on a decadal time scale.

The short-term dynamics of the Slufter were studied during a field campaign in 2008. The campaign aimed at identifying the dominant hydrodynamic processes and morphological change during fair weather conditions and during storm events. During fair weather flow velocities in the main inlet channel were 0.5-0.8 m/s at water depths of 0-1.5 m, slightly ebb-dominant and associated morphological change was small. When water levels were above critical levels during a storm period the hydrodynamics in the main channel drastically changed. The flow in the main channel was highly ebb dominant. Long ebb periods with typical flow velocities of 2 m/s were alternated by much shorter flood periods with typical velocities of 0.5-1 m/s. This resulted in a net outflow of water via the main channel, while we measured a net inflow of water at the beach plain. During the storm period in 2008 we measured a 10 m migration of the channel to the north.

We conclude that the Slufter is a storm-dominated tidal inlet system.

Spacio-temporal distribution patterns of North Sea Basin Early Oligocene (Rupelian) pteropoda (holoplanktonic gastropods: Mollusca, Gastropoda, Euthecosomata) are studied. These patterns indicate three short term invasions of a single pteropod species during the Rupelian. These invasions are indicated here as Clio blinkae Event, Praehyalocylis laxeannulata Event and Clio jacobae Event. The conspicuously short occurrences of the species, their abundances and some lithological features of the pteropod bearing strata lead to the conclusion that these plankton events are linked to sea level high-stands allowing currents from the worlds oceans to enter into the North Sea Basin.

Within the multidisciplinary WASA project, 160 cores up to 5 m long have been obtained from the back-barrier area and off the coast of the East Frisian island of Norderney. Thirty-seven contained basal peats on top of Pleistocene sands of the former Geest and 10 of them also had intercalated peats. Based on 100 acclerator mass spectrometry (AMS) 14C dates and analyses of botanical as well as zoological remains from the peats, lagoonal sediments and the underlying sands, a variety of distinct habitats have been reconstructed. On the relatively steep slopes north of the present island, a swampy vegetation fringe several kilometres wide with carrs of alder (Alnus glutinosa) moved in front of the rising sea upwards of the Geest as it existed then until roughly 6 ka, when the sea level reached the current back-barrier region of Norderney at around −6 m NHN (German ordnance datum). From then on for nearly 4000 years a changing landscape with a mosaic of freshwater lakes and fens existed within this area. It was characterised by various stands of Cladium mariscus (fen sedge), alternating with brackish reed beds with Phragmites australis (common reed) and salt meadows with Aster tripolium (sea aster), Triglochin maritima (sea arrowgrass), Juncus gerardii (saltmarsh rush) as well as mudflats with Salicornia europaea (common glasswort). As far as shown by our cores, this highly diverse, and for humans potentially attractive landscape was at least some 4 km wide and followed the coast for about 10 km. Before the rising sea caused diversification of habitats, wet heath as well as dry and dusty sand areas existed. In the course of time, parts of the wet heath turned into raised Sphagnum bogs under an oceanic precipitation regime before this diverse landscape was drowned by the rising sea and finally covered by marine sediments, while the earlier sediments and peats were partly eroded and redeposited.

In an area east of Leuven (central Belgium), a buried sandy estuarine deposit of Oligocene age contains a dark colored organic layer of about 4 m thick. Our results suggests that the organic matter is an illuvial horizon, therefore warranting the hypothesis that the layer may qualify for a giant buried spodic horizon rather than a remainder of a Tertiary oil seepage as suggested by Van Riessen and Vandenberghe (1996). Of particular importance is the micro-morphological evidence, which reveals that the mainly monomorphous organic matter is present as ubiquitous coatings and concentrations around the quartz grains. These coatings show the for Podzols very typical polygonal cracked patterns. The geochemical signature (stable carbon isotope analysis) also gives strong indications for a continental origin of the organic carbon and therefore support the pedogenetic origin of the horizon. The paleopedological scene into which this soil has developed is inferred from the data.

A combination of geological and anthropogenic processes have rendered theU.S. Gulf Coast in general – and the Mississippi Delta in particular –extremely sensitive to coastal hazard. Thus, the Katrina disaster was not aquestion of ‘if’ but of ‘when’. This contribution outlines thegeo-environmental context of the Mississippi Delta that evolved during the20th century and set the stage for Hurricane Katrina’s devastation. Thisincludes a brief discussion of the processes responsible for coastal erosionand wetland loss, the proposed measures to combat these problems, and thepolicy decisions (or, rather, the lack thereof) made so far. A connection ismade with the 1953 storm surge that devastated the southwestern Netherlandsand had a profound impact on Dutch science and engineering by providing theimpetus for the widely known and highly praised Delta Plan, as well as forunprecedented studies of Holocene sea-level change. Whether a similar routewill be followed for the Gulf Coast is primarily dependent on the amount ofpolitical will. Results are presented of recent studies of crustal movementsin the Mississippi Delta that show surprising long-term stability of thePleistocene basement, evidence that could prove critical for decision makerswith regard to the rebuilding process. Finally, the neglect of theprecarious situation along the Gulf Coast by the federal government isviewed as a possible metaphor for current U.S. policies with respect toscience in general, and to global warming in particular.

2D Basin modelling was used to evaluate the response of source rock maturation, and of petroleum expulsion, migration, accumulation and preservation to the evolution of the southern part of the inverted Broad Fourteens Basin. Modelling results show that the temperature, maturation and petroleum generation history as well as migration characteristics of both the Jurassic oil systems and the Carboniferous gas systems vary over short distances relative to the differences in burial history of the basin. Model results indicate that no major gas accumulations are preserved in the Slochteren Formation along the cross-section at present-day. Gas accumulations are predicted in sandstone-dominated Triassic units in the southern part of the section. Present-day oil accumulations predicted in the Vlieland Sandstone Formation sealed by the Vlieland Claystone Formation (in P9 and Q1 crestal structures) are in accordance with known oil accumulations. Additional oil accumulations are predicted in the sandstone-dominated Middle Werkendam Member, and in sandstones of the Delfland Subgroup.

The modelling offers an explanation for the different geochemical compositions of the accumulated oils in the P9 and Q1 areas. Modelling implies, that the oils in the Q1 oil field were sourced by remigrated oils expelled over time, from early mature to mature source rocks of the Posidonia Shale Formation. The biodegraded and water-washed nature of the Q1 oil is explained by the concentrated topography-induced groundwater flow through the Vlieland Sandstone Formation during the Late Cretaceous inversion of the basin. The oils accumulated in the P9 area were sourced from an early mature part of the Posidonia Shale Formation and were probably not affected by water washing and biodegradation because of post-inversion charging of the reservoir.

Radiocarbon dating of peat has its intrinsic problems. This is often caused by mobile organic fractions. For the Weichselian Pleniglacial, another methodological problem arises: the limit of the 14C dating method. This is discussed in terms of bulk (i.e. non-selected material, generally dated conventionally) vs AMS (i.e. selected botanical remains) dates, contamination, background and calibration, guided by a series of peat samples from the Belgian/Dutch border.

Turtle remains ascribed to the family Cheloniidae (Testudines, Cryptodira, Chelonioidea), collected from the lamarcki zone (Middle Turonian) at Wüllen (NW Germany) are described. The material consists of a right humerus, a scapula, a complete costalia, and costalia fragments of a single individual with the humerus indicating a primitive cheloniid of the ‘toxochelyid grade’. The present material, as well as previously recorded chelonioid humeri from the Cenomanian and Turonian of Germany illustrate a progressive diversification of chelonioids during the early Late Cretaceous.

This special issue of the Netherlands Journal of Geosciences / Geologie en Mijnbouw contains research papers offering important new insights into aspects of the occurrence of gas-production-induced seismicity in Groningen, the Netherlands. The issue is a ‘work in progress’ and provides a snapshot of our knowledge at the end of 2016, which is when most of the contributions were written.

In the aftermath of the Permo-Triassic mass extinction event, several reptile lineages radiated to form major components of marine faunas during the entire Mesozoic. The Lower Muschelkalk, which was deposited within a shallow inland sea in the Germanic Basin during the Middle Triassic, is one of the most important regions for understanding the early evolution of Mesozoic marine reptiles. Here, we present a new specimen from the Lower Muschelkalk of Winterswijk in the Netherlands, comprising an isolated left dentary that is morphologically distinct from any well-known Triassic vertebrate. We provide a detailed description of the jaw and the teeth using histological and micro-computed tomographic analyses. The anterior teeth are fang-like and curved, whereas the posterior teeth are wider and triangular-shaped. Tooth implantation is thecodont and teeth are ankylosed to the base of the alveolus. Replacement teeth are developed directly lingual to the functional teeth, starting with the formation of a resorption cavity on the dorsal surface of the alveolar margin. The replacement pattern cannot be observed in detail but is regular in the posterior part of the dentary with each tooth being alternated with an empty alveolus. The specimen can likely be assigned to Eosauropterygia based on its jaw morphology and dental morphology and replacement pattern, and it is remarkably similar to maxillae referred to the enigmatic Lamprosauroides goepperti from the Lower Muschelkalk of Poland. The dentary from Winterswijk lacks enlarged, ‘alveolarised’ crypts and corresponding distinct dental lamina foramina (DLFs) for the replacement teeth, a configuration that is typical of Sauropterygia, but which was likely not omnipresent in this clade. The specimen also exhibits loosely folded plicidentine at the roots of the teeth, likely representing the first identification of this feature in Sauropterygia.