The infill of an abandoned branch of the small river Vlootbeek, a tributary of the Meuse, revealed a record of the vegetation history from the Allerød to the Middle Ages, albeit with at least two hiatuses in its upper reach. Striking observations are the continuous presence of Pinus in a period long after this tree was absent elsewhere in the Dutch landscape, and the high percentages of Tilia pollen in the mid-Holocene. The former is explained by the sandy–gravelly subsoil in the valley of the Vlootbeek. The latter is ascribed to the short distance between the coring location and the plateau on which Tilia must have been the dominant tree. Anthropogenic influence is apparent from the Early Neolithic Linearbandkeramik farmers onwards.

Recent measurements of the chemical and isotopic composition of lunar samples indicate that the Moon's bulk composition shows great similarities with the composition of the silicate Earth. Moon formation models that attempt to explain these similarities make a wide variety of assumptions about the properties of the Earth prior to the formation of the Moon (the proto-Earth), and about the necessity and properties of an impactor colliding with the proto-Earth. This paper investigates the effects of the proto-Earth's mass, oblateness and internal core-mantle differentiation on its moment of inertia. The ratio of angular momentum and moment of inertia determines the stability of the proto-Earth and the binding energy, i.e. the energy needed to make the transition from an initial state in which the system is a rotating single body with a certain angular momentum to a final state with two bodies (Earth and Moon) with the same total angular momentum, redistributed between Earth and Moon. For the initial state two scenarios are being investigated: a homogeneous (undifferentiated) proto-Earth and a proto-Earth differentiated in a central metallic and an outer silicate shell; for both scenarios a range of oblateness values is investigated. Calculations indicate that a differentiated proto-Earth would become unstable at an angular momentum L that exceeds the total angular momentum of the present-day Earth–Moon system (L0) by factors of 2.5–2.9, with the precise maximum dependent on the proto-Earth's oblateness. Further limitations are imposed by the Roche limit and the logical condition that the separated Earth–Moon system should be formed outside the proto-Earth. This further limits the L values of the Earth–Moon system to a maximum of about L/L0 = 1.5, at a minimum oblateness (a/c ratio) of 1.2. These calculations provide boundary conditions for the main classes of Moon-forming models. Our results show that at the high values of L used in recent giant impact models (1.8 < L/L0 < 3.1), the proposed proto-Earths are unstable before (Cuk & Stewart, 2012) or immediately after (Canup, 2012) the impact, even at a high oblateness (the most favourable condition for stability). We conclude that the recent attempts to improve the classic giant impact hypothesis by studying systems with very high values of L are not supported by the boundary condition calculations in this work. In contrast, this work indicates that the nuclear explosion model for Moon formation (De Meijer et al., 2013) fulfills the boundary conditions and requires approximately one order of magnitude less energy than originally estimated. Hence in our view the nuclear explosion model is presently the model that best explains the formation of the Moon from predominantly terrestrial silicate material.

Topographic and morphologic models based on detailed Digital Elevation Models (DEM) of the Rur Graben, in particular a 33 km section of the Rurrand Fault, proved to be essential in preliminary investigations for the site selection of a trench for detailed paleoseismological investigations. The entire DEM in the 33 km Jülich-Düren area displayed as a color-shaded terrain map clearly illustrates the main features of the eastern border fault of the Rur Graben. As investigations concentrated on the 8x6 km Stetternich-Hambach section of the Rurrand fault, the use of contoured topographic, gray-shaded terrain and terrain slope maps helped delineate the main features of the surface fault expression. On the basis of topographic profiles constructed from the DEM, no fault scarp could be identified; however, the detailed surveying results from two geophysical profiles correlated well with the topographic data.

Two specimens of a pachydiscid ammonite, a fragmentary silicified phragmocone from the Kunrade Limestone facies at Kunrade (Schunck), and a partial external mould preserved in flint from the Nekum Member (both Maastricht Formation, Belemnitella junior Zone of authors) at the former Blom quarry (Berg en Terblijt), are identified as Pachydiscus (P.) noetlingi Kennedy, 1999, a species previously known only from the Upper Maastrichtian of Baluchistan (Pakistan). This new record underscores the proposal of incursions of Tethyan biota into the type area of the Maastrichtian Stage, previously documented for other groups, including echinoderms and bivalves, as well.

The spatial distribution of porosity and permeability of the Rupel Clay Member is of key importance to evaluate the spatial variation of its sealing capacity and groundwater flow condition. There are only a limited number of measured porosity and permeability data of the Rupel Clay Member in the onshore Netherlands and these data are restricted to shallow depths in the order of tens of metres below surface. Grain sizes measured by laser diffraction and SediGraph® in samples of the Rupel Clay Member taken from boreholes spread across the country were used to generate new porosity and permeability data for the Rupel Clay Member located at greater burial depth. Effective stress and clay content are important parameters in the applied grain-size based calculations of porosity and permeability.

The calculation method was first tested on measured data of the Belgian Boom Clay. The test results showed good agreement between calculated permeability and measured hydraulic conductivity for depths exceeding 200m.

The spatial variation in lithology, heterogeneity and also burial depth of the Rupel Clay Member in the Netherlands are apparent in the variation of the calculated permeability. The samples from the north of the country consist almost entirely of muds and as a consequence show little lithology-related variation in permeability. The vertical variation in permeability in the more heterogeneous Rupel Clay Member in the southern and east-southeastern part of the country can reach several orders of magnitude due to increased permeability of the coarser-grained layers.

This paper presents new geological data from two terp excavations at Englum and Ezinge, in the Dutch province of Groningen, and compares them to similar data from the western part of Friesland, in particular from the terp of Wijnaldum-Tjitsma. This terp is situated at a salt marsh ridge of the same height and thickness as Englum and Ezinge, although habitation started 650 years later at Wijnaldum. The measured levels of the tidal-flat/salt-marsh boundary underneath these terps make it possible to reconstruct palaeo-Mean High Water (MHW) levels. These sea-level index points show that palaeo-MHW in the Groningen part of the Wadden Sea was at the upper limit of the range of palaeo-MHW that has been reconstructed for the Dutch Wadden Sea on the basis of data from its western part. The deviating levels indicate that there are differences between regions of the Wadden Sea; this has earlier been established for the German section of the Wadden Sea. In the eastern part of the Dutch Wadden Sea, MHW nowadays is considerably higher than in the western part of the Wadden Sea; the data suggest that this may have been the case already in the 1st millennium BC. Salt marsh levels under dated terp layers make it possible to establish the rate of sedimentation of the developing salt marsh, at 23–91 cm per century for the pioneer zone and low marsh. This rate of development slowed to 4–5 cm per century for the middle marsh and 3–4 cm per century for the high salt marsh.

A fragmentary and partially dissociated arm of an astropectinid starfish, assigned to the genus Astropecten Gray, 1840, is recorded from decalcified and limonitised, fine-grained sandstone concretions and slabs of late Miocene (Tortonian) age, collected from the former gravel and sand pit ‘de Hoogdonk’ near Liessel, province of Noord-Brabant. Added are two examples of the ichnofossil Asteriacites lumbricalis von Schlotheim, 1820, both preserved in convex hyporelief and co-occurring with other, indeterminate traces. Although astropectinids have been recorded previously from Miocene and Pliocene deposits in the Netherlands, the present is the first record of fossilised traces of starfish.

In the conservation of fragile fossil bone material, impregnation by solvent-borne consolidant is often required. Understanding the mode of penetration of consolidants into fossil bone is of crucial importance. It is governed by a variety of factors; neutron imaging is a powerful tool to monitor and visualise this penetration (non-destructively). The consolidation of a vertebrate fossil from the Maastrichtian of the southeast Netherlands was imaged at the High Flux Reactor facility at Petten, the Netherlands. The analysis shows current conservation practice to result in a sufficiently deep and isotropic penetration.

New petrographical and geochemical evidence of tourmalinite pebbles from two Lower and three Middle Devonian formations from Belgium is presented. Petrography, REE, transition metal and microprobe data of the studied rocks suggest it are (meta)sediment-derived tourmalinites formed by boron metasomatism (and hydrothermal brecciation) in an intrusive setting. Tourmaline mineralizations within eastern Avalonia are known in south-east Ireland, the English Lake District and East Anglia. Based on previously suggested relations between Early Palaeozoic igneous activity in last two mentioned regions and the Brabant Massif, it is presumed that the Brabant Massif also underwent granite-related tourmalinization and that this was the source of the studied pebbles. Petrologie differences between pebbles found in Middle Devonian formations and pebbles from Lower Devonian formations, suggest that fluid circulation occurred on a regional scale, possibly extending into the Stavelot massif.

The ‘Wadden Sea Archive of landscape evolution, climate change and settlement history’ project (WASA) focuses on the analysis of marine sediment archives from the East Frisian Wadden Sea region. It aims at understanding the formation of palaeolandscapes since the end of the last ice age. One part of the project studies the possible correlation and shift of archaeological settlement patterns, climate change and sea-level rise through time in order to derive archaeological expectancy maps. In this paper we present our findings for a quantifiable set of Stone Age sites in the area of the prehistorical Dornumer tidal basin, discussing them against the background of coastal environmental factors and the applied methodology of our modelling. To enable spatial analysis of these sites, we developed a palaeographic elevation model, which was subsequently flooded at 2000-year intervals between the Boreal and early Subboreal periods. Particular challenges are posed by the dynamics of marine transgression, the related changes in the natural environment and their spatial extent. As a result of our GIS-based approach, the model can be extended geographically and provides a basis for future research.

The decline of domestic natural gas production, increasing dependency on gas imports and lagging development of renewable energy production may pose serious challenges to the current high standards of secure energy supply in the Netherlands. This paper examines synergy between hydrocarbon- and geothermal exploitation as a means to reinforce energy security. The Roden gas field is used as an example to demonstrate potential delay of water breakthrough in the gas well and a resulting increase of recovered gas (up to 19%), by positioning of a geothermal doublet in the water leg of the gas field. The reservoir simulations show that the total increase of gas production primarily depends on the amount of aquifer support. An optimal configuration of gas- and geothermal wells is key to maximise gas recovery and strongly depends on the distribution of reservoir properties. The study also reveals that this option can still be beneficial for gas fields in a late stage of production.

Net Present Value calculations show that the added value from the geothermal doublet on total gas production could lead to an early repayment of initial investments in the geothermal project, thereby reducing the overall financial risk. If no subsidies are taken into account, the additional profits can also be used to finance the geothermal project up to break-even level within 15 years. However, this comes with a cost as the additional profits from improved gas recovery are significantly reduced.

Until now hemispherical astylospongiid sponges were invariably referred to as Caryospongia juglans var. basiplana Rauff. Renewed investigations have now shown that part of the material should be assigned to a new genus and species, Tympanospongia vankempeni, which is characterised by a system of very irregular canals. These flat-based sponges originate from the Baltic region and occur in two assemblages of silicified Late Ordovician sponges known exclusively as erratics from The Netherlands and northern Germany. These fossils were transported by the River Eridanos, a former drainage system from the Baltic region that filled the North European Basin during the Miocene to Early Pleistocene. Specimens of Tympanospongia vankempeni gen. et sp. nov. also occur in the Upper Pleistocene of Gotland, Sweden. The new sponge described herein principally differs from other genera of the Astylospongiidae found frequently in the erratic sponge assemblages by its irregular system of apochetes which ramify and anastomose commonly.

During the 2007 ‘Kor en Bot’ collecting trip across the Oosterschelde (province of Zeeland, southwest Netherlands), on board trawler cutter ZZ10, a stem fragment of a fossil isocrinid was recognised amongst the contents of the nets pulled on deck. This specimen is here interpreted to be of Early Jurassic age and assignable to the genus Isocrinus. However, because only internodals are preserved in this pluricolumnal, specific identification cannot be but approximate (Isocrinus (Chladocrinus) cf. tuberculatus). In the absence of any outcrop of Jurassic deposits in Zeeland and adjacent Dutch and Belgian territory, the most likely explanation is that this crinoid represents erratic material transported by precursors of the present-day River Maas (Meuse). Between the Langres Plateau and Sedan (northeast France), this river cuts through several occurrences of Lower Jurassic strata from which the present isocrinid might have originated. A less likely explanation is that it stems from boulders used for coastal reinforcement or from a Roman limestone votive altarpiece put up at the temple complex for the goddess Nehalennia, formerly present at Colijnsplaat, near Domburg (Noord-Beveland, Zeeland). Transportation from either northwest France or the southern or eastern United Kingdom, where there are coastal exposures of Jurassic strata, via the North Sea, is another option which, however, is also considered less feasible in view of the good state of preservation of the crinoid.

Seismic hazard in low seismicity areas of Europe has traditionally been considered insignificant. However, in the light of the recently conducted paleoseismic studies along the Rhine Graben, a revision is required. Previously applied standard probabilistic seismic hazard assessment (PSHA) methods, using Poissonian approach for the earthquake occurrence, can now be substituted by renewal models where fault parameters such as the maximum magnitude, recurrence interval and the elapsed time since the last occurrence of a large earthquake, can be utilized. In this study, the application and the influence of the available paleoseismic data in the Lower Rhine Graben to seismic hazard analysis is demonstrated. The resulting hazard maps, when compared to the standard PSHA using Poissonian approach, indicate a more precise geographical distribution of the estimated seismic hazard levels. The influence of the paleoseismic data seem to be less important for return periods less than a 1000 years. Among the different input models, the highest values reach to 170 cm/sec2 for a 1000 year return period using a combination of Poissonian and renewal models.

Numerous archaeological investigations have been performed along the river Meuse in the Netherlands’ southeastern province of Limburg as part of the major ‘Maaswerken’ infrastructural project. To improve flood risk management and navigability, and for the purpose of gravel production and nature development, several areas of land covering a total of almost 2000 ha are being excavated to a great depth. In anticipation of this, archaeological research was performed for the purposes of recording and documenting archaeological remains in the most important areas and locations. From 1998 to 2015 the Cultural Heritage Agency of the Netherlands (Amersfoort) was in charge of the investigations, and acted as adviser to national public works agency Rijkswaterstaat.

The archaeological research connected with the Maaswerken project differed from regular, site-based investigations in terms of the landscape archaeology perspective on which it was based. The research themes and principles associated with this perspective were published in several documents, including a scientific policy plan published in 2004, and presented in further detail in area programmes and project briefs. The policy plan assigned each project area to one of five value assessment categories, based on the intactness of the landscape and the archaeological potential for addressing the research questions. In areas of high landscape intactness and great archaeological potential (category 1) the Agency selected zones to be surveyed and assessed, and for archaeological excavation. Though most of the fieldwork, including specialist analysis, was performed in these zones, other category project areas have also been the subject of archaeological fieldwork, including borehole surveys, site-oriented research and watching briefs, but on a more incidental basis. Observations were also made in the river Meuse itself and in the river's winter bed.

The archaeological investigations resulted in a large number of standard reports of desk studies and fieldwork, including reports of specialist analyses. A considerable proportion of these refer to the large-scale investigations at Borgharen and Itteren to the north of Maastricht, and at Lomm and Well–Aijen to the north of Venlo. The results of the investigations suggest the archaeological record here is rich and varied, with a time depth of c. 11,500 years, and traces of occupation and land use ranging from the Early Mesolithic (Well–Aijen, Borgharen) to the Second World War (Lomm).

This paper reflects on almost 20 years of archaeological research in the project areas of the Maaswerken and on the principles and methods used in the field research. The common thread is the results of landscape and archaeological studies and the relationship between them. Examples are used to illustrate results that can be regarded as important from a national perspective, and in terms of archaeological heritage management.

In the Netherlands, mineral extraction by means of dredging or quarrying meets with considerable societal resistance. Land surface lowering prior to large land reconstruction projects may raise fewer objections. We have calculated the potential yields of sand and gravel from land surface lowering embedded in planned building and construction projects, and in nature, farmland and recreation area development. Our primary data sets were a compilation of spatial plans for the period 1995 – 2005 and about 95,000 borehole descriptions. Even if embedded consistently, land surface lowering would contribute modestly (up to 5.4 Mio m3/a) to the filling sand provision (annual demand 45 – 50 Mio m3/a).

For more than 120 years since the name Caprovis savinii was founded on the basis of a bovid horn core from the ‘Forest Bed’ at Overstrand (Norfolk, UK), only one other find has been assigned to this species. Recently, two horn cores and one horn core fragment of the species have been discovered at two sand and gravel sorting centres in the Netherlands. The bone-bearing sediments are exposed on the North Sea floor, just off the coast of Great Yarmouth (Norfolk, UK). By comparing fossil and extant taxa, a classification within the bovid tribe Antilopini is proposed. Based on the accompanying fauna from the specific dredging area and the litho- and chronostratigraphy at Overstrand, C. savinii is placed within the Early Pleistocene.

The presence of salt in dilatant normal faults may have a strong influence on fault mechanics in the Groningen field and on the related induced seismicity. At present, little is known of the structure of these fault zones. This study starts with the geological evolution of the Groningen area, where, during tectonic faulting, rock salt may have migrated downwards into dilatant faults. These fault zones therefore may contain inclusions of rock salt. Because of its rate-dependent mechanical properties, the presence of salt in a fault may introduce a loading-rate dependency into fault movement and affect the distribution of magnitudes of seismic events. We present a first-look study showing how these processes can be investigated using a combination of analogue and numerical modelling. Full scaling of the models and quantification of implications for induced seismicity in Groningen require further, more detailed studies: an understanding of fault zone structure in the Groningen field is required for improved predictions of induced seismicity. The analogue experiments are based on a simplified stratigraphy of the Groningen area, where it is generally thought that most of the Rotliegend faulting has taken place in the Jurassic, after deposition of the Zechstein. This suggests that, at the time of faulting, the sulphates were already transformed into brittle anhydrite. If these layers were sufficiently brittle to fault in a dilatant fashion, rock salt was able to flow downwards into the dilatant fractures. To test this hypothesis, we use sandbox experiments where we combine cohesive powder as analogue for brittle anhydrites and carbonates with viscous salt analogues to explore the developing fault geometry and the resulting distribution of salt in the faults. Using the observations from analogue models as input, numerical models investigate the stick-slip behaviour of fault zones containing ductile material qualitatively with the discrete element method (DEM). Results show that the DEM approach is suitable for modelling the seismicity of faults containing salt. The stick-slip motion of the fault becomes dependent on shear loading rate with a modification of the frequency–magnitude distribution of the generated seismic events.