This paper integrates the sequence stratigraphic and tectonic data related to the Neogene geodynamic and palaeogeographic development of the African-Iberian plate boundary zone between Spain and Morocco. Though the dating of individual tectonostratigraphic sequences and their delimiting sequence boundaries varies in accuracy and precision, their apparent correlation strongly suggests contemporaneous development of the Betic and Rif basins. This may likely be attributed to regional changes of the overall compressional intra-plate stress field. This, in turn, was governed by coeval plate-kinematic changes related to the ongoing collisional convergence of Africa and Iberia. The Neogene succession is characterised by brief tectonic pulses that governed the sequence stratigraphic development of the Betic-Rif basins (NBR phases). It broadly correlates with the coeval sequences in the compressional foreland basins and extensional rift basins in front of the collisional Alpine and Pyrenean orogens (CRF phases). These regionally correlatable basinal deformation events indicate that stress-related episodic changes at the African-Iberian plate-boundary zone resulted in an essentially direct cause-and-effect relationship between the tectonostratigraphic evolution of Neogene basins in northern African (Morocco), southern Europe (Spain) and western Europe (France, Switzerland, Germany).

This paper presents the results of a detailed rock magnetic and magnetostratigraphic study of the Lower Oligocene Rupelian unit-stratotype. Notwithstanding the relatively low intensity of the natural remanent magnetisation and the diverse and often unstable behaviour during demagnetisation, close-spaced sampling and accurate polarity determinations allowed us to determine the magnetic polarity zonation. The recognition of the characteristic magnetic polarity and the correlation with the standard magnetobiochronologic time scale yields an accurate chronostratigraphic dating of the Boom Clay Formation. The boundary between the geomagnetic chrons C12n and C12r nearly coincides with the lithostratigraphic boundary between theTerhagen and Putte Members. Rock magnetic techniques point to magnetite and probably also iron sulphides as the main magnetic remanence carriers. These magnetic minerals could, however, not be identified with classical mineralogical techniques performed on magnetic extractions. The failure to detect them may be due to the low concentration of these minerals, the small grain size, and the close physical relation with pyrite.

The provenance of coarse-grained ice-rafted detritus has been studied, based on material collected from the SE Greenland margin. The sediment was sampled by a 1.5 m3 video-grab from 1256 m water depth. The fraction > 1cm was macroscopically investigated and a thin-section analysis was made. The results clearly show that East Greenland north of the Denmark Strait is the source region of the material sampled. The main provenance is from areas adjoining Kangerdlugssuaq Fjord, Blosseville Kyst, Scoresby Sund, Kong Oskar Fjord, and Kejser Franz Joseph Fjord. It can thus be demonstrated that significant ice-stream activity and iceberg calving occurred there. Present-day iceberg production is mainly concentrated to the Scoresby Sund, but the other areas apparently represent locations of larger ice-stream activity during periods prior to the Holocene.

More generally, it can be concluded that southerly surface-water flow similar to the present East Greenland Current must also have occurred prior to the Holocene. Although either North America (Canada) or Scandinavia - or both - are generally referred to as important regions for the provenance of ice-rafted detritus, we conclude that (East) Greenland may have been an important source for (late) glacial North Atlantic ice-rafted detritus production as well.

Geological structures and Late Quaternary stratigraphy of the shallow subsurface along the southernmost Danish North Sea coast have been investigated using seismic data and shallow boreholes. A large-scale glaciotectonic thrust complex has been mapped in an area of 15 km by 40 km in the Fanø Bugt area. The affected succession consists of Neogene and Quaternary sediments deformed down to a depth of 200 – 360 m. A kineto-stratigraphic correlation to onshore glaciotectonic deformation suggests that the deformation took place during a westward advance stage of the Late Saalian (Warthe) glaciation. The western limit of the glaciotectonic structures constitutes an N-S striking deformation front situated 35 km off the west coast. Based on the glacial stratigraphy outside the deformation front, it is suggested that the same ice advance that caused the glaciotectonic deformation, eroded the top of the thrust sheets, and subsequently deposited a lower unit of meltwater sediments and an upper heterogenous glacigenic unit. The upper glacigenic unit forms a bank about 30 km offshore. Between the bank and the shore, the surface of the Saalian glacial landscape forms a wide depression ca. 50 m below sea level. This basin has controlled deposition in the area since the late Saalian and is filled with sediments of late Saalian, Eemian, Weichselian and Holocene age. The base of the Holocene marine deposits is thus a flat erosional surface extending eastward several kilometres below the onshore coastal areas and the northern Wadden Sea. This surface was transgressed 8800 years ago. An inverted, in plan view T-shaped, Holocene sand accumulation approximately 25 km long, 30 km wide and 15 – 25 m thick is situated on top of this surface at Blåvands Huk. According to recent estimates by the Danish Coastal Protection Board some 2.5 million m3 sediments are supplied annually to the system from the north. In the last 3000 years, 25 km of the west coast and the associated shoreface slope have prograded ca. 3 km towards the west forming a barrier spit complex. Large aeolian dunes and cover sands now conceal the spit complex. Extending twenty km west of Blåvands Huk is a highly dynamic bank, the Inner Horns Rev, with active sand-accumulation on the slopes. The Inner Horns Rev bank has grown ca. 3.5 km westward during the last 800 years. The deposits seem to be sourced by the coastal longshore sand transport from the north. The Outer Horns Rev was previously assumed to be a Saalian terminal moraine. However, this investigation reveals that it is also mainly a Holocene marine accumulation landform, but sourced from the west. Other sand accumulations, which are situated 20 – 30 km west of the coast, are probably sourced from both the south and the west.

Modelling of surface and shallow subsurface data is getting more and more advanced and is demonstrated mostly for onshore (hydro)geological applications. Three-dimensional (3D) modelling techniques are used increasingly, and now include voxel modelling that often employs stochastic or probabilistic methods to assess model uncertainty. This paper presents an adapted methodological workflow for the 3D modelling of offshore sand deposits and aims at demonstrating the improvement of the estimations of lithological properties after incorporation of more geological layers in the modelling process. Importantly, this process is driven by new geological insight from the combined interpretation of seismic and borehole data. Applying 3D modelling techniques is challenging given that offshore environments may be heavily reworked through time, often leading to thin and discontinuous deposits. Since voxel and stochastic modelling allow in-depth analyses of a multitude of properties (and their associated uncertainties) that define a lithological layer, they are ideal for use in an aggregate resource exploitation context. The voxel model is now the backbone of a decision support system for long-term sand extraction on the Belgian Continental Shelf.

Despite increasing research into changes in the discharge of the River Meuse, estimates of the river’s sediment yield are less forthcoming. Three published studies (in 1883, 1982, and 1987) have estimated suspended sediment yield at the Belgian-Dutch border; the latter two studies surmise that this increased substantially between the late 19th and 20th Centuries. In this paper a more recent and longer time-series of observed discharge and suspended sediment data (1995 – 2005) is used to estimate mean annual suspended sediment yield (ca. 386,000 Mg.a−1), and the results of the previous studies are revisited. New insights suggest that those studies do not in themselves provide evidence of increased sediment yield: the higher estimates in the late 20th Century could equally be due to interannual variability or methodological differences. Furthermore, there has been no significant increase in rainfall erosivity between the late 19th and 20th Centuries, and the effect of land use change over that time would have been to cause a decrease in suspended sediment yield, rather than an increase.

This paper describes the landscape evolution of the Waasland Scheldt polders in the north of Belgium from the Late Glacial – early Holocene to the present time, and the effects of this changing landscape on the human settlement. The regional landscape evolution has been visualised in a series of palaeogeographical maps for successive time frames. Two different map series were produced: a series of Holocene palaeogeographical reconstructions (11,000–950 cal BP) based on geotechnical, geological and archaeological data, and a series of post-Medieval landscape reconstructions (16th- to 19th-century) based on historical maps, land registers and soil data. Additional palaeoenvironmental information from fossil pollen and plant remains allowed reconstruction of the vegetation and wetland changes, particularly for the middle to late Holocene. Peat growth was the main key to understanding the landscape evolution of the Waasland Scheldt polders. Whereas the landscape evolution during the Holocene was mainly sea-level driven, the transformation of the landscape during the last millennium was largely due to human interventions.

Paleoseismological techniques have been used to investigate gravitational deformations at the Mortirolo Pass (Valtellina region, central Alps), in order to improve the knowledge on the activation mechanisms and the evolution of deep-seated gravitational slope movements. The deformation has been responsible for mass sliding towards the Valtellina depression through the activation of several-hundred-metre-long shear planes. Minor shear planes dipping towards the mountain played the role of antithetic structures. Four trenches were excavated across scarps representing the surficial expression of shear planes affecting the bedrock and Late Pleistocene-Holocene deposits. The excavations enabled to investigate the stratigraphy of Quaternary deposits and the geometry and kinematics of the shear planes affecting them. Radiocarbon analyses on organic material contained in sediments and paleosols enabled to define a succession of displacement events which occurred during the Late Pleistocene-Holocene. Collected data indicate the persistence of the activity until recent times (last movement related to 1810-1540 cal. BP). A sudden movement has been detected along one of the main shear surfaces (dipping towards the valley) with a vertical displacement of several metres. In contrast, numerous displacements (with lower vertical offset) have been detected along the antithetic shear planes. Different hypotheses have been proposed in the past to define the origin of huge gravitational movements (glacial retreat, uplift of the Alpine chain, fault activity). However, the Late Pleistocene cycles of glacial loading and unloading on the mountain slopes seem to be the most probable factors causing deep-seated gravitational movements in the investigated region. A recent dramatic landslide in an area adjacent to the investigated one (Mt. Zandila-Valpola) testifies to the paroxistic evolution of the large scale gravitational deformations. The densely inhabited Valtellina region is affected by a large number of gravitational structures similar to those of the Mortirolo area. In consideration of the possible effects of the paroxistic activation of these structures, detailed studies on the chronology and kinematics of the deformations through the application of paleoseismological techniques should therefore be encouraged.

The results from analyses of botanical remains (pollen, wood, charcoal, seeds) from several archaeological features excavated in Kluizen (northern Belgium) are presented. The region was largely uninhabited until the Iron Age and Roman period when a rural settlement was established, resulting in small-scale woodland clearance. The site was subsequently abandoned from c. AD 270 till the High Middle Ages. The results of the archaeological and archaeobotanical analyses provide information on changes in land use and resulting dynamics of woodland cover and composition between c.600 BC and AD 1200, with a spatial and temporal resolution unrivalled in northern Belgium. Especially the long period of woodland regeneration following abandonment of the site around AD 270, covering the Late Roman and Early Medieval period, could be reconstructed in detail. Abandoned fields were first covered with pioneer woodland (Salix, Corylus and Betula), then Quercus-dominated secondary forest and finally a late-successional forest with Fagus sylvatica, Carpinus betulus and Ilex aquifolium, an evolution that took over 300 years. The results also indicate that the observed increase of Fagus during the Early Middle Ages, which was never an important element in the woodland vegetation in northern Belgium before, was related to climatic changes rather than anthropogenic factors.

Previous locations of earthquakes induced by depletion of the Groningen gas field were not accurate enough to infer which faults in the reservoir are reactivated. A multiplet analysis is performed to identify clusters of earthquakes that have similar waveforms, representing repeating rupture on the same or nearby faults. The multiplet analysis is based on the cross-correlation of seismograms to assess the degree of similarity. Using data of a single station, six earthquake clusters within the limits of the Groningen field were identified for the period 2010 to mid-2014. Four of these clusters were suitable for a relocation method that is based on the difference in travel time between the P- and the S-wave. Events within a cluster can be relocated relative to a master event with improved accuracy by cross-correlating first arrivals. By choosing master events located with a new dense seismic network, the relocated events likely not only have better relative, but also improved absolute locations. For a few clusters with sufficient signal-to-noise detections, we show that the relocation method is successful in assigning clusters to specific faults at the reservoir level. Overall, about 90% of the events did not show clustering, despite choosing low correlation thresholds of 0.5 and 0.6. This suggests that different faults and/or fault segments with likely varying source mechanisms are active in reservoir sub-regions of a few square kilometres.

We report here a large mosasaur skull, preserved three-dimensionally in a concretion recovered from Ziebach County, South Dakota, USA. This fossil represents the first articulated mosasaur skull from the Trail City Member of the Fox Hills Formation and the first definitive occurrence of Mosasaurus hoffmanni Mantell, 1829 from that area and the northernmost occurrence in the Western Interior Seaway, greatly extending the paleobiogeographic range of this taxon. The age of this specimen is determined to be between 68.3 and 67.6 Ma based on the associated invertebrate fauna. Although previous authors have suggested synonomy of the North American Mosasaurus maximus Cope, 1869 and the European M. hoffmanni, this is the most comprehensive analysis to date and is based on comparisons with Mosasaurus specimens recovered across the Northern Hemisphere, allowing an emended diagnosis of the species M. hoffmanni. Minor differences are considered individual variation or to reflect ontogenetic stage, including slender dentaries in some individuals, range of development of the C-shaped notch of the coronoid and differences in the shape of the supratemporal fenestra.

Humankind has been interested in space throughout the ages and studies of the universe and our own solar system have been ongoing since the first observations of celestial bodies. In the current era space exploration has provided in situ data for the different bodies in our solar system. To fully comprehend the underlying processes occurring in these bodies, missions and telescope observations are, however, not sufficient and additional modelling studies, both numerical and analogue, are necessary. In this paper we present a new facility specifically designed to experimentally study organic compounds under simulated planetary (sub)surface conditions on rocky bodies in our solar system: PALLAS, the Planetary Analogues Laboratory for Light, Atmosphere, and Surface Simulations. We give an overview of planetary conditions that can be simulated in this facility and that are known to affect organic compounds: radiation, atmospheric composition, temperature and surface composition.

The morpho-genetic evolution of the upper Aller valley (Weser basin, North Germany) was reconstructed using geological and géomorphologie data integrated within a numerical process model framework (FLUVER-2). The current relief was shaped by Pre-Elsterian fluvial processes, Elsterian and Saalian ice sheets, followed by Weichselian fluvial processes. Structural analysis based on subsurface data and morphological interpretations were used to reconstruct uplift/subsidence rates. A detailed analysis led to the hypothesis that we are dealing with either a NNW-SSE or a WSW-ENE oriented compression leading to uplift in the upper Aller valley. It is also hypothesised that the NNW-SSE compression might have caused strike-slip deformation leading to differential block movement and tilt. Two different uplift rate scenarios were reconstructed and used as a variable parameter in numerical modelling scenarios simulating the Late Quaternary longitudinal dynamics of the Aller. Each different scenario was run for 150.000 years and calibrated to the actual setting. The resulting model settings were consequently evaluated for their plausibility and validity. Subsequently, regional semi-3D simulations of valley development were made to test the two tectonic stress hypotheses. Differential tectonic uplift and regional tilt seems to have played an important role in shaping the current valley morphology in the upper Aller. Unfortunately, due to the uncertainties involved, we were unable to discriminate between the two postulated tectonic stress scenarios.

Since so little is still known of the marine prehistoric environment, present management actions tend to be guided by the gathering of disparate sets of data obtained as part of regulatory practice and/or from opportunistic finds that are not necessarily specifically targeted towards archaeology. Our view is that we need to develop a clearly defined set of questions about the marine prehistoric cultural resource to enable the design of targeted scientific research, as part of both the regulatory process and marine management generally. In this paper we argue that it is crucial to understand both natural and anthropogenic context, and this necessarily includes work on the Quaternary geology. Furthermore, we argue for a greater regulatory emphasis on identifying and initiating what we should do (for the long term) rather than what we can and are doing (for the short term) to identify the best means to manage the prehistoric marine environment.

This study presents an annually resolved dendrochronological reconstruction of hydrological impacts on the Roman and early-medieval landscape in the Low Countries of northwestern Europe. Around 600 hydrologically sensitive ring-width patterns, mostly oak (Quercus robur/petraea) as well as some ash (Fraxinus excelsior) and elm (Ulmus sp.), were selected from an initial dataset of >5000 and compiled into two chronologies that span the first millennium AD. Their content and (dis)similarities to established tree-ring chronologies from this and surrounding regions were used to assess their provenance, which in both cases is in the area where the majority of the wood was recovered. Instances of high groundwater levels and/or inundation were catalogued by identifying multi-year intervals of strongly reduced annual growth that occurred simultaneously throughout the research area. The resulting record contains 164 events dated between AD 1 and 1000, of which 21 have a recurrence frequency ≥50 years. One-third of the ≥50-yr events date between AD 185 and 282, making this the most flood-intense interval of the first millennium. The severest reconstructed impact of the first millennium dates to AD 602. A comparison to historically documented river floods/sea breaches and drought/heat spells shows that the predominant cause of the inferred impacts in the research area was river overflow. Synchronous inundation responses of oaks preserved in former bogs in Lower Saxony (NW Germany) indicate that half of the reconstructed events occurred on a supra-regional level, pointing to regional precipitation as a main forcing. River floods documented in written sources do not seem to have affected tree growth in Lower Saxony in a significant manner, indicating that the majority of documented floods most likely were caused by hydrological circumstances upstream of the catchments of the Rhine and/or Meuse. Reconstructed flood impacts during the Early Middle Ages coincide remarkably well with construction and repair of Rhine revetments at the early-medieval site of Leiderdorp-Plantage in the western Netherlands.

The majority of running geothermal plants worldwide are located in geological settings with convection- or advection-dominant heat transport. In Germany as in most regions in Europe, conduction is the dominating heat transport mechanism, with a resulting average geothermal gradient. The geothermal play type concept is a modern methodology to group geothermal resources according to their geological setting, and characteristic heat transport mechanisms. In particular, the quantity of heat transport is related to fluid flow in natural or engineered geothermal reservoirs. Hence, the permeability structure is a key element for geothermal play typing. Following the existing geothermal play type catalogue, four major geothermal play types can be identified for Germany: intracratonic basins, foreland basins and basement/crystalline rock provinces as conduction-dominated play types, and extensional terrains as the convection-dominated play type. The installed capacity of geothermal facilities sums up to 397.1 MWth by the end of 2018. District heating plants accounted for the largest portion, with about 337.0 MWth. The majority of these installations are located in the play type ‘foreland basin’, namely the Molasse Basin in southern Germany. The stratigraphic unit for geothermal use is the Upper Jurassic, also known as ‘Malm’ formation, a carbonate reservoir with high variability in porosity and permeability. Recently drilled wells in the southernmost Molasse Basin indicate the Upper Jurassic as a tight, fracture-controlled reservoir, not usable for conventional hydrothermal well doublets. Our new data compilation including the recently drilled deep geothermal well Geretsried reveals the relation of porosity and permeability to depth. The results suggest that obviously diagenetic processes control permeability with depth in carbonate rock, diminishing the predictability of reservoir porosity and permeability. The play type concept helps to delineate these property variations in play type levels because it is based on geological constraints, common for exploration geology. Following the general idea of play typing, the results from this play analysis can be transferred to geological analogues as carbonate rock play levels in varying depth.

Inoceramid bivalve shells from outcrops of mid-Maastrichtian deep-water carbonate, hemipelagic beds in the Bay of Biscay exhibit post-depositional diagenetic alteration. New data from isotopic analysis (carbon and oxygen), together with observations of the inoceramid shells and carbonate host-rock using cathodoluminescence (CL) and scanning electron microscopy (SEM), confirm a lateral, westerly increase in the degree of diagenesis, without any substantial textural changes in the alternating dark and clear growth lines of the shell microstructure. Under CL, a bright yellowish to red colour is observed in the most diagenetically altered inoceramid samples. Non-luminescent areas are restricted to the central parts of the less altered shells. A detailed geochemical analysis by electron microprobe, along intrashell profiles of the non-luminescent and luminescent zones has revealed that Mg/Ca, Sr/Ca, Na/Ca, Fe/Ca and Mn/Ca ratios show oscillatory curves but behave differently. Fe/Ca, Mn/Ca and Na/Ca ratios are well correlated but usually show an opposite relationship when compared with the Mg/Ca and Sr/Ca ratios of both luminescent and non-luminescent shell areas. Our findings have palaeoenvironmental implications in that the geochemistry of the regular, alternating dark and clear growth lines seems to be related to the input of seasonally controlled phytodetritus to the basin floor.

The Groningen field is the largest onshore gas field in Europe. Continuous production since 1963 has led to induced seismicity starting in the early 1990s. Production measures aimed at lowering the level of seismicity have been implemented since 2014. In this paper we start from an empirical relationship between the cumulative number of seismic events and cumulative gas production. We show that a better way to analyse the data is to relate the ratio of activity rate over production rate versus the cumulative production, such that the model parameters and their uncertainty can be determined. This also allows us to make predictions including the confidence intervals.

Using this model, we first performed regression analysis based on the larger seismic catalogue which includes all recorded events with a magnitude of 1.3 and larger, because we consider this value to be the magnitude of completeness since 1995. We have also performed regression analysis based on a smaller seismic catalogue consisting of all events with a magnitude of 1.5 and larger. This was done in order to be able to compare our forecast with forecasts performed by others. Our prediction for 2016, based on the seismic catalogue of all events with a magnitude of M≥1.5 (using only the events recorded before 2016), was 16±8 events. By the end of 2016, 13 such events had been recorded.

We discuss a number of factors which may influence the predictive power of the derived relationship and which require further study. For instance, we consider the delay between production and earthquakes which increases with decreasing reservoir pressure. In addition, the effect of seasonal fluctuation in Groningen production should be considered. Future work can be done to include these effects in the empirical model. We also investigated the challenges related to the applicability of the analysis to sub-regions of the Groningen field.

We reanalysed the induced seismicity data from the Groningen gas reservoir. We used the well-maintained induced event catalogue of the KNMI. The distributions of seismic moments and interevent times show a power law behaviour over several decades, and we find that upon increasing the magnitude threshold, these distributions remained scale-invariant. Because of this scale-invariance, we can put a constraint on the average loading of the elastic energy within the reservoir, which upon reaching a critical value gives rise to the seismic events. We find that the elastic energy roughly increases proportional to time. We also propose a new machine learning approach for declustering the seismic events, separating correlated from independent events. We find that only few events are truly independent, i.e. exponentially distributed over time. There are also few aftershocks following an Omori-type power law. The bulk of events presents a Gamma distribution for interevent times. This gives us an indication that the rigidity in the reservoir is high, but whether this results in overall correlated events should be settled with physics-based arguments rather than statistical ones.

The size, shape and spatial position of lithofacies types (or facies architecture) in a tidal estuarine basin are complex and therefore difficult to model. The tidal currents in the basin concentrate sand-sized sediment in a branching pattern of tidal channels and fringing tidal flats. Away from the sandy tidal flats the sediment gradually changes to mud-dominated heterolithic deposits and clay. In this paper the facies analysis of a tidal estuarine basin, the Holocene Holland Tidal Basin (HHTB) is presented based on core data and Cone Penetration Tests (CPT). Four lithofacies associations are recognized: (1) tidal channel sand, (2) sand-dominated heterolithic inter-tidal flat, (3) mud-dominated heterolithic inter-channel and (4) fresh-water peat. The high data density allowed for the construction of a detailed facies architecture model in which the size, shape and spatial position of the tidal estuarine facies elements were established. The results can be used to improve the reservoir modelling in highly heterogeneous estuarine reservoir settings.