The availability of nearly 100 years of bathymetric measurements allows the analysis of the morphodynamic evolution of the Dutch Wadden Sea under rising sea level and increasing human constraint. The historically observed roll-over mechanisms of landward barrier and coastline retreat cannot be sustained naturally due to numerous erosion control measures that have fixed the tidal basin and barrier dimensions. Nevertheless, the large continuous sedimentation in the tidal basins (nearly 600 million m3), the retained inlets and the similar channel-shoal characteristics of the basins during the observation period indicate that the Wadden Sea is resilient to anthropogenic influence, and can import sediment volumes even larger than those needed to compensate the present rate of sea-level rise. The largest sedimentation occurs in the Western Wadden Sea, where the influence of human intervention is dominant. The large infilling rates in closed-off channels, and along the basin shoreline, rather than a gradual increase in channel flat heights, render it likely that this sedimentation is primarily a response to the closure of the Zuiderzee and not an adaptation to sea-level rise. Most of the sediments were supplied by the ebb-tidal deltas. It is, however, unlikely that the sediment volume needed to reach a new equilibrium morphology in the Western Wadden Sea can be delivered by the remaining ebb-tidal deltas alone.

Following a time of expansion of the oil industry, the period 1987-2012 and especially the second half of it reflects a diversification of exploration activities in the Netherlands. In addition to the ongoing discovery of classical hydrocarbon reservoirs, successful attempts have been made to explore deep geothermal energy. Shale gas and Coal Bed Methane received interest in the Netherlands too but so far no wells have been drilled in order to test the potential. Storage of gas and liquids has been introduced and salt mining more or less continued without many changes. In terms of drilling activity, the last 25 years show a decreasing trend and the discovered volumes are smaller. Testing of new play concepts was either successful (shallow gas) or not (Dinantian) and sometimes an unexpected discovery was made (Triassic Fat Sands). New techniques proved older fields to be exploitable again, e.g. redevelopment of the Schoonebeek Field. Therefore, despite a decline in number of wells drilled and reserves added, the diversification of use of the subsurface will guarantee ongoing exploration.

Evidence-based interpretations of fluvial evolution, and especially of river-terrace formation, have advanced significantly in recent decades, with a notable contribution made by activities of the Fluvial Archives Group. Well-dated river-terrace sequences provide frameworks for the understanding of landscape evolution, since they record valley-floor levels that were higher in the past, attributable, from their patterns of occurrence, to regional uplift. The role of climate fluctuation during the Quaternary is also paramount, since this has been an important driver of the varied fluvial activity that has given rise to the staircases of terraces that characterise the temperate latitudes. This approach is contrasted with a more theoretical methodology for using rivers as recorders of landscape evolution, again with an emphasis on uplift, based on the concept of the formation of knickpoints at particular base levels and their migration upstream. Although different timescales can be explored by the two methods, the concept of headward-migrating knickpoints implies a mechanism for incision that is difficult to reconcile with the formation of the broadly parallel river terraces that are observed in many systems. Knickpoints can frequently be observed to coincide with gorge reaches, where river valleys are constricted as a result of resistant bedrock and/or the effects of localised active crustal deformation. This raises the possibility that knickpoints have generally formed in response to factors of local geology rather than migrating from downstream.

Tidal channel networks, estuaries and ebb deltas are usually formed over a period longer than observations cover. Much is known about their characteristics and formation from linear stability analyses, numerical modelling and field observations. However, experiments are rare whilst these can provide data-rich descriptions of morphological evolution in fully controlled boundary and initial conditions. Our objective is to ascertain whether tidal basins can be formed in experiments, what the possible scale effects are, and whether morphological equilibrium of such systems exists.

We experimentally created tidal basins with simple channel networks and ebb deltas in a 1.2 by 1.2 m square basin with either a fixed or self-formed tidal inlet and initially flat sediment bed in the tidal basin raised above the bed of the sea. Rather than create tides by varying water level, we tilted the entire basin over the diagonal. The advantage of this novel method is that the bed surface slopes in downstream direction both during flood and ebb phases, resulting in significant transport and morphological change in the flood phase as well as the ebb phase. This overcomes the major problem of earlier experiments which were entirely ebb-dominated, and reduces the experiment time by an order of magnitude.

Ebb deltas formed in sand were entirely bedload dominated whereas the lightweight plastic sediment was intermittently suspended. Channels bifurcated during channel deepening and backward erosion to form a network of up to four orders. For initially dry tidal plains, the tidal prism increased as more sediment eroded from basin to ebb delta, so that evolution accelerated initially. The rate of change, the size of the channels and the final length of channels and delta were very sensitive to the tidal amplitude, tidal period and initial water depth in the basin. Most experiments with sand terminated with all sediment below the threshold for motion, whilst lightweight sediment remained mobile in the inlet region and firstorder channels, suggesting that sustained morphodynamics are feasible in experiments. We discuss how this novel experimental setup can be extended to produce tidal deltas, estuaries and other tidal systems and study their dynamics as a function of their forcing.

The Late Pleistocene surface paleohydrography of the New Jersey Pine Barrens consisted of a series of broad braided alluvial surfaces with meandering paleochannels. This drainage is best explained in terms of impermeable (i.e. frozen) substrate, high sediment load, variable or decreasing discharge, and eolian sedimentary dynamics. Evidence for eolian activity is provided by wind-abraded sand grains, coversand, dunes, ventifacts, deflation hollows and wind-polished boulders. In several places stream avulsion occurred due to channel infilling by locally-derived wind-blown sediment. The braided and meandering river systems that characterise the tundra and polar semi-desert lowlands of the Western Canadian Arctic are described as modern analogs.

A five years geological mapping project, in which the Netherlands Continental Shelf has been re-examined using all publicly available data, resulted in an important update of the existing dataset. The stratigraphy of over 400 wells has been re-interpreted. New depth and thickness grids, based mainly on the interpretation of 3D seismic data have been produced for the most important stratigraphic intervals from Permian Upper Rotliegend to Neogene. New reservoir grids describe the top, base and thickness of 30 (potential) reservoir units in the area. In addition, the uncertainty related to interpretation and further processing of the data has been assessed. This resulted in maps displaying the standard deviation for the depth of the main stratigraphic intervals. Based on these results and the data already available for the onshore area, an updated structural element map was made for the Netherlands.

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.

In the Weichselian, the Lower Rhine in the Dutch-German border region has used three courses, dissecting ice-marginal topography inherited from the Saalian. In the Late Weichselian, the three courses functioned simultaneously, with the central one gaining importance and the outer ones abandoning. This study aims to reconstruct the fluvial development and forcings that culminated in abandonment of the northern branch ‘Oude IJssel-Rhine’, at the time of the Lateglacial to Holocene transition. The fluvial architecture is studied using a cored transect over the full width of the valley, detailed cross-sections over palaeochannels and geomorphological analysis using digital elevation and borehole data. Biostratigraphy, radiocarbon dating and OSL dating provide a timeframe to reconstruct the temporal fluvial development. In its phase of abandonment, the fluvial evolution of the Oude IJssel-Rhine course is controlled by the ameliorating climate and related vegetation and discharge changes, besides by intrinsic (autogenic) fluvial behaviour such as the competition for discharge with the winning central branch and the vicinity of the Lippe tributary confluence. The rapid climate warming at the start of the Late Glacial resulted in flow contraction as the initial response. Other fluvial geomorphic adjustments followed, with some delay. An aggrading braided or transitional system persisted until the start of the Allerød, when channel patterns finally changed to meandering. Floodplain incision occurred at the Allerød - Younger Dryas transition and a multi-channel system developed fed by Rhine discharge. At the start of the Holocene, this system transformed into a small-scale, local meandering system, which was abandoned shortly after the start of the Holocene.

The final abandonment of the Oude IJssel-Rhine and Niers-Rhine courses can be attributed to deep incision of the Central Rhine course in the earliest Holocene and is considered to be controlled by flow contraction induced by climate and related vegetation and discharge changes.

The Zechstein salt in the Dutch part of the North Sea Basin played a key role in the generation of successful petroleum plays. This is not only because of its sealing capacity, but also because the salt occurs in structures that provide lateral and vertical traps. The structural styles of areas with thick salt and those with none- or thin salt are completely different during phases of extensional or compressional tectonics. This indicates that, indirectly, the depositional thickness of the main Zechstein salt is essential in regulating the loci of the Dutch petroleum systems. In this paper we aim at quantifying current ideas on the relationship between 1) depositional salt thicknesses; 2) structural style of the main structural elements identified in the Dutch subsurface; 3) timing of deformation; and 4) thickness of the overburden. By finalisation of TNO's subsurface mapping program (see Kombrink et al., this issue), several data products are available that allow evaluation of these relationships. The depositional thickness of the salt was estimated using iterative smoothing of the present day thickness, the results of which account both for regional thickness variations and volume preservation (99%). Fault-distribution analysis shows that faults are only able to penetrate salt with a depositional thickness of <300 m, a transition that demarcates the division between thin- and thick-skinned salt tectonics. In the southern offshore where the salt is thin or absent, the overburden shows the same fault pattern throughout the stratigraphic sequence. In the northern realm, where salt is thicker than 300 m, the salt layer acted as decollement and sub- and supra salt strain are dissimilar. A strong genetic and temporal relationship exists between periods of regional tectonism, halokinetic intensity and thickness distribution of the Zechstein overburden. This relationship is further proven by burial history analysis across two selected profiles in the northern offshore. The analysis focuses on the vertical distribution of the salt by taking into account the depositional and erosional history of the salt overburden, without a-priori defined periods of salt flow. The results corroborate the notion that platforms and highs experienced less extension during the major phases of Jurassic rifting and further suggest that the absence of a thick Jurassic overburden precludes major salt flow during this tectonic phase. Main salt flow was triggered during the Sub-Hercynian and later phases of compression resulting in salt pillow geometries. In the basinal areas, where the Jurassic succession is thickest, salt diapirs and walls formed that are almost exclusively linked to major subsalt faults. Main salt flow occurred during Late Kimmerian rifting, whereas some minor structuration occurred during Sub-Hercynian inversion.

Investigation of landforms on the eastern margin of the East Anglian Fenland basin has demonstrated that they represent a series of glaciofluvial delta-fan and related sediment accumulations (the Skertchly Line) deposited at the margin of an ice-lobe that entered the depression. This ‘Tottenhill glaciation’ dated to ca 160 ka, or the late Wolstonian (= late Saalian) Stage, is equivalent to that during the Netherlands' Drenthe Substage (Marine Isotope Stage 6). Of these landform complexes, an additional site at Shouldham Thorpe, previously nominated as the stratotype for deposits linked to a pre-Anglian Stage, Midlands'-derived Ingham/‘Bytham river’, has now been studied. Examination of the internal structure and form of the feature, using ground-penetrating radar (GPR), supported by section logging, borehole records, local landscape morphology and previous description, together indicate that the deposits rest on an eroded surface of Lowestoft Formation diamicton (Anglian Stage) and must therefore be of post-, rather than pre-Anglian age. The investigations indicate that the Shouldham deposits were laid down as a glacio-marginal subaerial (‘terminoglacial’) fan at the ice-front. In common with other sequences in the Skertchly Line complexes, deposition at Shouldham Thorpe was accompanied by minor ice-front movement, this fan potentially being deposited before retreat to the Tottenhill locality. The implications of the results are discussed.

This paper presents and discusses the distribution of fluid and leak-off pressure data from the subsurface of onshore and offshore Netherlands in relation to causes of formation fluid overpressure and the permeability framework. The observed fluid pressure conditions demonstrate a clear regional difference between the southern and the north and north-eastern part of the study area. In the southern area, formation fluid pressures are close to normal and well below measured leak-off pressures. In the north, formation fluids are overpressured and may locally even approach the measured leak-off pressures. The regional differences in fluid overpressure can, in large part, be explained by differences in geologic framework and burial history. In the south, relatively low rates of sedimentary loading and the presence of relatively permeable sedimentary units have led to the currently observed normally pressured conditions. In the northern area, relatively rapid Neogene sediment loading plays an important role in explaining the observed overpressure distributions in Cenozoic mudstones, Cretaceous Chalk and Rijnland groups, and probably also in Jurassic units. The permeability framework of the northern and north-eastern area is significantly affected by Zechstein and Triassic salt deposits and structures. These units are characterised by very low permeability and severely restrict fluid flow and pressure dissipation. This has created hydraulically restricted compartments with high overpressures (for example overpressures exceeding 30 MPa in the Lower Germanic Trias Group in the Terschelling Basin and Dutch Central Graben).

Modelling of the shallow subsurface of the Dutch Wadden Sea is merely based on lithological information extracted from a limited amount of core samples. In order to improve the subsurface model and to provide a better basis for engineering purposes, seismic data have recently been acquired, processed and interpreted. This study focuses on the interpretation of seismic data in a pilot area in the southwestern part of the Dutch Wadden Sea near the Afsluitdijk. In order to acquire a maximum detail of subsurface information in a time-efficient way, multiple types of seismic systems were deployed simultaneously in a ‘one-sweep-survey’, providing information over depth ranges up to 60 m subsurface depth. Data from three seismic systems are presented; a chirp system, a boomer and sparker source in combination with hydrophone streamers. Geological interpretation of the seismic data was made by identifying seismic facies units and subsequently correlating them to geological cross-sections, running parallel to the Afsluitdijk. Geological cross-sections were derived from the existing geological and hydrogeological model and from relatively densely spaced borehole information. Six key reflectors were identified on the seismic data along the Dutch Afsluitdijk that make up four seismic facies units. Results of seismic profiles show good recognition of internal structures in especially Holocene sediments. A clay plug and a shallowing of a channel at the eastern side of the pilot area were interpreted as channel infills resulting from the rather sudden dominance by newer tidal channels to the west, probably coinciding with the opening of the Marsdiep channel. The channel wall deposits observed were interpreted as a turning of the drainage channel after closure of the IJsselmeer. Strong reflections of deeper levels (>15 m below Dutch vertical datum, i.e. N.A.P.) were interpreted as clay/sand interfaces in the Middle-Pleistocene Urk Formation and were more continuous than previously thought. It is concluded that high resolution seismics add valuable information yielding improved understanding of the sedimentary structure of the shallow subsurface, which in turn can be useful for near future engineering works along the Afsluitdijk.

Subsurface temperature is a key parameter for geothermal energy prospection in sedimentary basins. Here, we present the results of a 3D temperature modelling using a thermal-tectonic forward modelling method, calibrated with subsurface temperature measurements in the Netherlands. The first step involves the generation of a coherent dataset of temperature values for the calibration of the model. In the Netherlands, most of the available measurements (98.8%) are BHT measurements and therefore need to be corrected from the thermal perturbation created during drilling. The remaining 1.2% is composed of DST measurements, which closely resemble the formation temperature (i.e., ±5 °C). The resulting dataset, after correction, gives a total number of 1293 values in 454 wells. Included in this dataset are 412 highly reliable values corrected with the Instantaneous Cylinder Source (ICS) method and 829 values of a lower reliability corrected with the AAPG method. In addition to the corrected values, 52 DST values in 26 wells are available from the Dutch subsurface. The average thermal gradient of this whole dataset is 31.3 °C/km with a surface temperature of 10.1 °C. The second step in the modelling process was the generation of a 3D forward model that focuses on calculating the temperature distribution of the sedimentary basin fill, taking into account the basin evolution of the past 20 Myrs and thermal properties and processes of the whole lithosphere. From the 3D thermal model, we extracted 2D cross sections across well locations to compare model temperatures with calibration data. Furthermore, we present vertical profiles, isodepth maps and temperature projection on geological layers, to discuss the relationship between temperature and geology. Anomalies in this relationship can have several causes and include: 1) the extreme thermal conductivity and complex geometry of the Zechstein salt; 2) enhanced radiogenic heat production of the upper crust due to magmatic intrusions. In addition, our model supports earlier findings that shallow hydrothermal convection in highly permeable sediments can effectively lower thermal conductivity and temperatures in shallow sediments.

An equilibrium dune-erosion model is used every six years to assess the capability of the most seaward dune row on the Dutch Wadden islands to withstand a storm with a 1 in 10,000 probability for a given year. The present-day model is the culmination of numerous laboratory experiments with an initial cross-shore profile based on the central Netherlands coast. Large parts of the dune coast of the Wadden islands have substantially different dune and cross-shore profile characteristics than found along this central coast, related to the presence of tidal channels, ebb-tidal deltas, beach-plains and strong coastal curvature. This complicated coastal setting implies that the predictions of the dune-erosion model are sometimes doubtful; accordingly, a shift towards a process-based dune-erosion model has been proposed. A number of research findings based on recent laboratory and field studies highlight only few of the many challenges that need to be faced in order to develop and test such a model. Observations of turbulence beneath breaking waves indicate the need to include breaking-wave effects in sand transport equations, while current knowledge of infragravity waves, one of the main sand transporting mechanisms during severe storm conditions, is strongly challenged by laboratory and field observations on gently sloping beaches that are so typical of the Wadden islands. We argue that in-situ and remote-sensing field observations, laboratory experiments and numerical models need to be the pillars of Earth Scientific research in the Wadden Sea area to construct a meaningful process-based dune-erosion tool.

While climatic models of valley downcutting discuss the origin of terrace staircases in valleys of middle Europe within the frame of alternating cold and temperate periods of the Quaternary, other models, starting from a base level fall imposed by an initial tectonic signal, describe the response of the drainage network mainly as the propagation of an erosion wave from the place of base level fall (the margin of the uplifted region) toward the headwaters, the two types of model being rarely confronted. In the Ardennes (West Europe), cosmogenic 10Be and 26Al ages have recently been calculated for the abandonment of the Younger Main Terrace (YMT) level, a prominent feature at mid-height of the valleysides marking the starting point of the mid-Pleistocene phase of deep river incision in the massif. These ages show that the terrace has been abandoned diachronically as the result of a migrating erosion wave that started at 0.73 Ma in the Meuse catchment just north of the massif, soon entered the latter, and is still visible in the current long profiles of the Ardennian Ourthe tributaries as knickpoints disturbing their upper reaches. At first glance, these new findings are incompatible with the common belief that the terraces of the Ardennian rivers were generated by a climatically triggered stepwise general incision of the river profiles. However, several details of the terrace staircases (larger than average vertical spacing between the YMT and the next younger terrace, varying number of post-YMT terraces in trunk stream, tributaries and subtributaries) show that a combination of the climatic and tectonic models of river incision is able to satisfactorily account for all available data. The cosmogenic ages of the YMT also point out a particular behaviour of the migrating knickpoints, which apparently propagated on average more slowly in the main rivers than in the tributaries, in contradiction with the relation that makes knickpoint celerity depend directly on drainage area. We tentatively suggest a process accounting for such anomalies in migration rates.

This paper aims to provide a synthesis and update concerning the fluvial terraces of the rivers flowing from the Vosges Massif (Moselle and palaeo Upper-Moselle-Meuse, Meurthe, Sarre). The terraces of these rivers are especially well-developed in the marly depressions of the Eastern Paris Basin, justifying an extensive field mapping expedition. The main rivers exhibit terrace staircases with 8 to 13 stepped terrace steps within 100m of the present valley floor. The fluvial sediments mainly originate from the Vosges Massif (crystalline basement and Permo-Triassic sandstones and conglomerates). Another peculiarity of the study area is the presence of several palaeovalleys, typically related to fluvial capture events which occurred to the detriment of the River Meuse. Many palaeomeanders have also been recognised in the Paris Basin (Meuse catchment), and the Rhenish Massif (Moselle and Sarre valleys). Despite some similarities, palaeoenvironmental reconstructions provide evidence for the terrace staircases being distinct from one valley / section of valley to another. These differences are related to the morphostructural framework and to the climate forcing (presence/absence of glaciers in the upper catchment of the rivers). The chronological framework suggests that the terrace sequences and the main capture events may be older than previously thought.

Hydrogeological research in coastal areas has gained considerable attention over the last decades due to increasing stresses on fresh groundwater resources. Fundamental groundwater flow and solute transport analyses remain essential for a concise understanding of the governing processes that lead to salinisation of fresh groundwater resources. However, the challenge of modern research is the application and quantification of these processes in real world cases. In this context, deltaic areas are amongst the most difficult study areas as they often have a complex groundwater salinity distribution. The Wadden Sea area in the northern part of the Netherlands is an example of such an area.

We quantified salt water intrusion and salinisation of groundwater flow systems in two representative case studies in the Wadden Sea area, using the density dependent groundwater flow and transport code M0CDENS3D. The results indicate that sea-level rise and autonomous processes will cause severe salinisation in the future, especially in the low polder areas close to the sea. In addition, we show that enhanced land subsidence due to salt exploitation accelerates this process. Salinisation can be mitigated to some extent by raising surface water levels in polders and by creating saline groundwater collection areas that maintain a low controlled water level.