bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of salt tectonics and overburden in the generation of overpressure in the Dutch North Sea area
Authors: Nelskamp S. , Verweij J.M. , Witmans N.
Published: July 2016

In this paper we study the effects of timing of salt movement and mechanical compaction on the generation of overpressures in Mesozoic rocks. To that end we apply 2D basin modelling on two N-S trending cross sections in the Dutch Central Graben and Terschelling Basin, respectively. Several overpressuring scenarios were calculated by modifying the mechanical compaction of the sealing layer, the rate of sedimentation, and the timing of salt movement. Pressure and porosity measurements from several wells along the cross sections were used as calibration data. The results show that rapid sedimentation and early compaction of Pliocene to Quaternary mudstones explain most of the overpressures in the Cretaceous and Jurassic rocks. The modifications of the mechanical compaction of the Upper Cretaceous Chalk Group performed in this study could not explain the overpressure anomalies in the southern part of the Dutch Central Graben. Processes such as chemical compaction are probably more important in this respect. Overpressures in the Triassic are mainly controlled by the timing of salt movement and the closure of lateral seals. This study has lead to a better understanding of the processes that generate overpressures and those that are involved in their lateral distribution. The integration of modelling scenarios and information on the timing of seal formation enables to define new play concepts and is important for the assessment of possible drilling hazards as well.
Revision and update of the Callovian-Ryazanian Stratigraphic Nomenclature in the northern Dutch offshore, i.e. Central Graben Subgroup and Scruff Group
Authors: Munsterman D.K. , Verreussel R.M.C.H. , Mijnlieff H.F. , Witmans N. , Kerstholt-Boegehold S. , Abbink O.A.
Published: July 2016

Exploration in a mature basin requires a detailed classification and standardisation of rock stratigraphy to adequately comprehend the depositional history and prospect architecture. The pre-Quaternary Stratigraphic Nomenclature of the Netherlands compiled by Van Adrichem Boogaert & Kouwe in 1993 provided a consistent framework for use by the Dutch geological community. Over the past twenty years, new biostratigraphic techniques and continued exploration in the Netherlands have provided additional stratigraphic information. Based on this information the Late Jurassic lithostratigraphy in particular, shows significant inaccuracies. The Callovian-Ryazanian strata from the northern offshore of the Netherlands' territorial waters, termed the Central Graben Subgroup and Scruff Group, reveal a complex sedimentary history. The combination of non-marine to shallow marine lateral facies changes, repetitive log and facies characteristics in time, sea-level and climate change, salt tectonics and structural compartmentalisation hamper straightforward seismic interpretation and log correlation. Recognition of three genetic sequences by Abbink et al. in 2006 enabled an improved reconstruction of the geological history. Further improvements in refinement and reliability of the stratigraphy together with new information on the facies and ages of the successions and about the subsequent tectonostratigraphic development of the northern Dutch offshore area form the basis of the present revision. As a result, earlier lithostratigraphic models have been changed and new lithostratigraphic relationships and names are introduced in this paper.
Direct heat resource assessment and subsurface information systems for geothermal aquifers; the Dutch perspective
Authors: Kramers L. , van Wees J.-D. , Pluymaekers M.P.D. , Kronimus A. , Boxem T.
Published: July 2016

A resource assessment methodology has been developed to designate prospective high permeable clastic aquifers and to assess the amount of potential geothermal energy in the Netherlands. It builds from the wealth of deep subsurface data from oil and gas exploration and production which is publicly and digitally available. In the resource assessment various performance indicator maps have been produced for direct heat applications (greenhouse and spatial heating). These maps are based on detailed mapping of depth, thickness, porosity, permeability, temperature and transmissivity (methodology presented in other papers in this NJG issue). In the resource assessment analysis 14 lithostratigraphic units (clastic aquifers) have been considered, ranging in age from the Permian to the Cenozoic. Performance maps have been made which include a) the expected doublet power (MWth) to be retrieved; b) the number of houses or hectares that can be heated from one doublet; and c) a potential indicator map, which provides insight in subsurface suitability for specific applications from a techno-economic perspective. To obtain a nationwide overview of the resource potential in terms of recoverable geothermal energy, a progressive filtering approach was used from total heat content of the reservoirs (Heat In Place – HIP) via the heat that can potentially be recovered (Potential Recovery Heat – PRH) to energy maps taking into account a techno-economic performance evaluation (Recoverable Heat – RH). Results show that the HIP is approximately 820,000 PJ which is significantly more than previous estimates of around 90,000 PJ. This considerable increase in geothermal energy potential is the result of accurate geological mapping of key reservoir properties and the development of state-of-the-art techno-economic performance assessment tools that performs Monte Carlo simulation. Moreover, for the previous estimates boundary conditions were set with the aim to compare the geothermal potential between different EU countries (Rijkers & Van Doorn, 1997). Taking into account techno-economic aspects, the RH is in the order of 85,000 PJ. This is equivalent to ~70% of the ultimate recoverable gas of the Slochteren Gas field. In total over 400 maps have been created or used as input for the resource assessment. Together, they provide comprehensive information for geothermal energy development from various stakeholder perspectives. The maps can be interactively assessed in the web-based portal ThermoGIS (www.thermogis.nl). This application complements existing subsurface information systems available in the Netherlands and supports the geothermal community in assessing the feasibility of a geothermal system on a regional scale.
Morphodynamic development and sediment budget of the Dutch Wadden Sea over the last century
Authors: Elias E.P.L. , van der Spek A.J.F. , Wang Z.B. , de Ronde J.
Published: July 2016

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.
Climate-driven fluvial development and valley abandonment at the last glacial-interglacial transition (Oude IJssel-Rhine, Germany)
Authors: Janssens M.M. , Kasse C. , Bohncke S.J.P. , Greaves H. , K.M. Cohen  , Wallinga J. , Hoek W.Z.
Published: July 2016

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.
A novel methodological approach for thin-section description and its application to periglacially disturbed Pleistocene deposits from Danbury, Essex, UK
Authors: Leszczynska K. , Boreham J. , Boreham S.
Published: July 2016

Although micromorphological terminology has been evolving since 1960, there have been few attempts to create a systematic approach to the description of thin-sections which would serve as a guiding tool for inexperienced researchers, students, and all new to the field of micromorphology. In this paper we present a novel, decision tree based systematic approach for thin-section description. This new approach attempts to unify micromorphological descriptions of Quaternary deposits, regardless of the character of the deposit and the purpose of the analysis.

In this research project, named ‘Hidden Ice Worlds’, the micromorphology of an 8 m thick sequence of periglacially disturbed deposits from the Royal Oak Pit, Danbury hill, Essex, UK is described. This sequence is situated on the eastern side of Danbury hill, at c. 50 m OD. Based on micromorphological analyses, a new hypothesis for the evolution of this sequence is presented. Multiple phases of physical reworking associated with freezing and thawing of the deposit, subsequent to Elsterian (Anglian) glaciation (480-420 ka BP) is proposed as the main process responsible for the evolution of the sequence. As periglacially derived deposits are usually removed from such elevated locations on hill' slopes, inversion of the topography is proposed as a necessary factor for the formation and preservation of the sequence described in this atypical location.
3D modelling of the shallow subsurface of Zeeland, the Netherlands
Authors: Stafleu J. , Maljers D. , Gunnink J.L. , Menkovic A. , Busschers F.S.
Published: July 2016

The Geological Survey of the Netherlands aims at building a 3D geological voxel model of the upper 30 m of the subsurface of the Netherlands in order to provide a sound basis for subsurface related questions on, amongst others, groundwater extraction and management, land subsidence studies, aggregate resources and infrastructural issues. The Province of Zeeland (SW Netherlands, covering an area of approximately 70 by 75 km) was chosen as the starting point for this model due to an excellent dataset of 23,000 stratigraphically interpreted borehole descriptions.

The modelling procedure involved a number of steps. The first step is a geological schematisation of the borehole descriptions into units that have uniform sediment characteristics, using lithostratigraphical, lithofacies and lithological criteria. During the second modelling step, 2D bounding surfaces are constructed. These surfaces represent the top and base of the lithostratigraphical units and are used to place each voxel (100 by 100 by 0.5 metres) in the model within the correct lithostratigraphical unit. The lithological units in the borehole descriptions are used to perform a final 3D stochastic interpolation of lithofacies, lithology (clay, sand, peat) and if applicable, sand grain-size class within each lithostratigraphical unit. After this step, a three-dimensional geological model is obtained. The use of stochastic techniques such as Sequential Gaussian Simulation and Sequential Indicator Simulation, allowed us to compute probabilities for lithostratigraphy, lithofacies and lithology for each voxel, providing a measure of model uncertainty.

The procedures described above resulted in the first fully 3D regional-scale lithofacies model of the shallow subsurface in the Netherlands. The model provides important new insights on spatial connectivity of sediment units of, for example, sandy Holocene tidal channel systems. Our results represent a major step forward towards a fully 3D voxel model of the Netherlands.
NewNothosaurusskulls from the Lower Muschelkalk of the western Lower Saxony Basin (Winterswijk, the Netherlands) shed new light on the status ofNothosaurus winterswijkensis
Authors: Albers P.C.H.
Published: July 2016

Three nothosaur skulls from the Lower Muschelkalk (Lower Anisian) locality of Winterswijk, the Netherlands, were recently acquired by museum Twentse Welle (Enschede) and have thereby become available for scientific description. Thus, these skulls had been identified asNothosaurus winterswijkensis, but upon examination these skulls challenge the status of thisNothosaurus species. All diagnostic characters are somehow discredited, but the material can also not be unequivocably be considered asNothosaurus marchicus, which is the only other obvious candidate. As these fossils originate from the same strata as the type ofNothosaurus winterswijkensisand there is no reason to assume that the animals occupied different ecological niches they are more plausibly considered one species, andNothosaurus winterswijkensistherefore becomes a junior synonym ofNothosaurus marchicus. The diagnosis ofNothosaurus marchicusis enlarged to include all finds.
OSL dating of an inland dune along the lower River Scheldt near Aard (East Flanders, Belgium)
Authors: Bogemans F. , Vandenberghe D.
Published: July 2016

The chronostratigraphic position of aeolian dunes in East Flanders (Belgium) has been under debate for decades. Until now, the only available age information consisted of a limited number of radiocarbon dates, which provided indirect sediment deposition chronologies. This paper reports on the first direct determination, by quartz-based single-aliquot optically stimulated luminescence dating, of the time that dune sands were deposited along the Lower River Scheldt in Belgium. The sediments are dated at 12.0±0.9 ka (n = 5), which confirms that the time of inland dune formation in East Flanders dates from the Younger Dryas period and should not be constrained to the Holocene.
Comment on: Mid-Holocene water-level changes in the lower Rhine-Meuse delta (western Netherlands): implications for the reconstruction of relative mean sea-level rise, palaeoriver-gradients and coastal evolution by Van de Plassche et al. (2010)
Authors: Hijma M.P. , Cohen K.M.
Published: July 2016

In May 2009, Orson van de Plassche sadly passed away. In a paper of which parts, especially the discussion section, were written after his death, new data and a revision of an existing sea-level curve are presented for the Rotterdam area (Van de Plassche et al., 2010). This comment concerns two topics addressed in the discussion section: 1) connection of their revised Rotterdam relative sea-level curve for the period 7900-5300 cal yr BP (MSL-R2; Jelgersma, 1961; Van de Plassche, 1982; 1995; Berendsen et al., 2007; Van de Plassche et al., 2010) to the sea-level curve for the same area for the period 9000-7500 cal yr BP (MSL-R1; Hijma & Cohen, 2010); 2) The role of the river gradient on the calculation of the magnitude of a sea-level jump that occurred between 8450-8250 cal yr BP (Hijma & Cohen, 2010).
Reply to the comment by M.P. Hijma & K.M. Cohen on the paper by Van de Plassche et al. (2010)
Authors: Makaske B. , Hoek W.Z.
Published: July 2016

First of all, we want to stress that this reply to the comment by Hijma & Cohen on the paper by Van de Plassche et al. (2010) reflects our personal view and not necessarily the opinion of the first author of the paper under discussion, Orson van de Plassche. After a long career dedicated to sea-level research, Orson passed away on May 4, 2009, and left us with the Vlaardingen data set and his explicit wish to publish this material, which ultimately led to the Van de Plassche et al. (2010) paper. In the present paper we will: (1) give some background information on the Vlaardingen data set and the special circumstances under which the Van de Plassche et al. (2010) paper was written; (2) reply to the comment on the construction of our revised mean sea-level curve (MSL-R2); (3) reply to the comment on our suggestion that the palaeoriver-gradient might influence sea-level jump magnitude calculations.

The paper by Van de Plassche et al. (2010) is primarily based on the Vlaardingen data set that was collected by Orson van de Plassche in the mid-1980s, in a sequel to his PhD project (Van de Plassche, 1982). Soon after the start of the Vlaardingen project Orson became busily occupied with sea-level research in North America, leaving the Vlaardingen data set virtually unpublished (some data were published in Van de Plassche (1995)).
Palaeoecological study of a Weichselian wetland site in the Netherlands suggests a link with Dansgaard-Oeschger climate oscillation
Authors: van Geel B. , Bos J.A.A. , van Huissteden J. , Pals J.P. , Schatz H. , van Mourik J.M. , van Reenen G.B.A. , Wallinga J. , van der Plicht J.
Published: July 2016

Botanical microfossils, macroremains and oribatid mites of a Weichselian interstadial deposit in the central Netherlands point to a temporary, sub-arctic wetland in a treeless landscape. Radiocarbon dates and OSL dates show an age between ca. 54.6 and 46.6 ka cal BP. The vegetation succession, starting as a peat-forming wetland that developed into a lake, might well be linked with a Dansgaard-Oeschger climatic cycle. We suggest that during the rapid warming at the start of a D-O cycle, relatively low areas in the landscape became wetlands where peat was formed. During the more gradual temperature decline that followed, evaporation diminished; the wetlands became inundated and lake sediments were formed. During subsequent sub-arctic conditions the interstadial deposits were covered with wind-blown sand. Apart from changes in effective precipitation also the climate-related presence and absence of permafrost conditions may have played a role in the formation of the observed sedimentological sequence from sand to peat, through lacustrine sediment, with coversand on top. The Wageningen sequence may correspond with D-O event 12, 13 or 14. Some hitherto not recorded microfossils were described and illustrated.
Lower Cretaceous of the southern North Sea Basins: reservoir distribution within a sequence stratigraphic framework
Authors: Jeremiah J.M. , Duxbury S. , Rawson P.
Published: July 2016

Facies belts exhibit a back-stepping trend towards the London Brabant/ Rhenish Massif through the Early Cretaceous. The overall eustatic sea-level rise was punctuated by short-term tectonic events identified either as localised or North Sea wide in extent. The biostratigraphically constrained sequences have, for the first time, allowed a detailed calibration of tectonic and eustatic events on a North Sea scale. The most extensive database available to any North Sea Cretaceous study was available to the authors together with a comprehensive suite of new high-resolution biostratigraphy and sedimentology. This has allowed unique insights into provenance, depositional environment, extent of sequence stratigraphical events and the degree to which unconformities have been tectonically accentuated.
A striated, far travelled clast of rhyolitic tuff from Thames river deposits at Ardleigh, Essex, England: evidence for early Middle Pleistocene glaciation in the Thames catchment
Authors: Rose J. , Carney J.N. , Silva B.N. , Booth S.J.
Published: July 2016

This paper reports the discovery of an in-situ striated, far-travelled, oversized clast in the Ardleigh Gravels of the Kesgrave Sands and Gravels of the River Thames at Ardleigh, east of Colchester in Essex, eastern England. The morphology, petrography and geochemistry of the clast, and the sedimentology of the host deposit are described. The striations are interpreted, on the basis of their sub-parallelism and the shape and sub-roundedness of the clast, as glacial and the clast is provenanced to Ordovician rocks of the Llŷn and Snowdonia regions of North Wales. On the basis of clast frequency within the Colchester Formation gravels of the Kesgrave Sands and Gravels it is inferred that glaciers reached the Cotswold region of the Thames catchment. Floe-ice transport during spring flood is invoked for movement from the glaciated region to eastern England. The paper discusses the possible age of the glaciation and recognises that it is difficult to be more precise than a cold stage in the early Middle Pleistocene (MIS 18, 16 or 14). Attention is drawn to the possibility of glaciation associated with a diamicton in the region of the Cotswold Hills known as the Bruern Till, but stresses the need for new work on this deposit.
The interactions between Quaternary Geology and Archaeology
Authors: Hoek Wim Z.
Published: July 2016

This special issue focuses on the interactions between Quaternary Geology and Archaeology and results from the INQUA-NL Symposium: ‘Late Quaternary Climate Change: a Human Perspective’ held on April 14th2009, KNAW Trippenhuis, Amsterdam. The symposium was attended by over 125 scientists and students with interest in the fields of Quaternary Geology and Archaeology. The symposium was organized for the INQUA Netherlands commission (INQUA-NL) by Wim Hoek, Faculty of Geosciences, Utrecht University (UU), Henry Hooghiemstra, Faculty of Science, University of Amsterdam (UvA), and Jos Deeben, National Service for Cultural Heritage (RCE). The INQUA Netherlands commission (INQUA-NL) is the Netherlands' national representation in INQUA, the International Union for Quaternary Research (see furtherwww.geo.uu.nl/inqua-nl).

The Netherlands is a country made by humans, but before the large-scale impact of humans that formed the typical Dutch landscape, people inhabited our area and needed to be able to deal with natural disasters like climate change, river floods or sea-level change. In the field of archaeology, there is increasingly more space to include the environmental changes that partly determined the behaviour of prehistoric communities. The interactions between quaternary geology and archaeology are not only restricted to provide stratigraphical information during archaeological prospection or on exposures during excavations. Quaternary geology is increasingly applied to gain insight in the landscape development and environmental setting where people have lived in the past. Above this, predictive models can be improved by the interaction of archaeological and geological/palaeogeographical research (see also Deeben et al., 2010).
Middle Palaeolithic artefact migration due to periglacial processes; a geological investigation into near-surface occurrence of Palaeolithic artefacts (Limburg-Eastern Brabant coversand region, the Netherlands)
Authors: Deeben J. , Hiddink H. , Huisman D.J. , Müller A. , Schokker J. , Wallinga J.
Published: July 2016

The original distribution pattern of Middle-Palaeolithic artefacts may be affected by tectonic movement, sedimentation and periglacial processes. This is e.g. the case in the coversand area of Limburg and Eastern Brabant (NL), where the occurrence of numerous finds in a SW-NE trending zone across the Roer Valley Graben is considered enigmatic. In order to elucidate the processes affecting the spatial distribution and the chance of recovery of such artefacts, we investigated a site in Nederweert. At this site, several Middle-Palaeolithic artefacts had been recovered earlier from unexpectedly shallow depths. A test pit profile and grain size analyses revealed that the shallow sediments at this site have been affected by intense, multi-phase cryoturbation, which has deformed the sand and loam layers and partially mixed them thoroughly. As a result, optically stimulated luminescence dating of these sediments yielded widely scattered single-aliquot equivalent dose distributions. Using a Finite Mixture Model (FMM), it was estimated that cryoturbation caused mixing of sediments deposited between 12 and 50 ka with sediment grains deposited between 60-150 ka. The latter material is probably the original context of the Middle-Paleolithic artefacts. Apparently, cryoturbation and potentially other periglacial processes have transported artefacts closer to the surface. Based on these results, we suggest that the occurrence of Middle-Palaeolithic artefacts is caused by (1) the tectonically-induced spatial distribution of layers of this age and (2) periglacial processes having caused migration of artefacts towards the surface. Although periglacial processes may facilitate finding Middle Palaeolithic artefacts, they may severely disturb the original context to such an extent that Middle Palaeolithic sites can no longer be identified. The results of this study form a basis for improving the Indicative Map of Archaeological Values that is used to predict the presence of archaeological sites. The insights gained are also relevant to other areas where Middle-Palaeolithic sites are affected by periglacial processes.
A molluscan perspective on hydrological cycle dynamics in northwestern Europe
Authors: Versteegh E.A.A. , Vonhof H.B. , Troelstra S.R. , Kroon D.
Published: July 2016

Shell aragonite δ180 values of unionid freshwater mussels are applied as a proxy for past river discharges in the rivers Rhine and Meuse, using a set of nine shells from selected climatic intervals during the late Holocene. A single Meuse shell derives from the Subboreal and its δ180 values are similar to modern values. The Rhine specimens represent the Subboreal, the Roman Warm Period and the Medieval Warm Period (MWP). These shells also show averages and ranges of aragonite δ180 values similar to modern specimens. This indicates that environmental conditions such as Rhine river dynamics, Alpine meltwater input and drought severity during these intervals were similar to the 20th century. These shells do not record subtle centennial to millennial climatic variation due to their relatively short lifespan and the large inter-annual and intra-seasonal variation in environmental conditions. However, they are very suitable for studying seasonal to decadal scale climate variability. The two shells with the longest lifespan appear to show decadal scale variability in reconstructed water δ180 values during the MWP, possibly forced by the North Atlantic Oscillation (NAO), which is the dominant mode of variability influencing precipitation regimes over Europe.
Human presence in the central Netherlands during early MIS 6 (~170-190 Ka): evidence from early Middle Palaeolithic artefacts in ice-pushed Rhine-Meuse sediments
Authors: van Balen R.T. , Busschers F.S.
Published: July 2016

Part of the gravelly deposits of a combined Rhine-Meuse river of Middle Pleistocene age in the central Netherlands contains early Middle Palaeolithic artefacts. Although not in their original position, a significant part of these artefacts is hardly abraded, indicating limited fluvial transport. The artefacts have mainly been made from fluvial flint gravel boulders, originating from the Meuse catchment. Thus far, inferences for the age of the artefacts are based on the stratigraphic context and floral and faunal remains, which suggest a MIS 7 age. In this paper, OSL dating carried-out in the framework of a research aimed at the paleogeographical reconstruction of the Rhine-Meuse fluvial system in the central Netherlands and a review of published data are used to provide absolute age constraints for the artefact-bearing deposits. It is argued that the deposits were formed during the glacial phase directly preceding the Drenthe substage of the late Saalian (early MIS 6), and that at least a part of the artefacts has approximately the same age.
Climate-proofing the flood protection of the Netherlands
Authors: Vellinga P. , Marinova N. , van Loon-Steensma J.M.
Published: July 2016

Global sea level is rising at an increased rate since the late 19th century as a result of rising global mean temperatures. This rise is geographically non-uniform, with substantial spatial differences, and in the latest decade faster than expected. New evidence suggests that more rapid changes than indicated in the Fourth IPCC report take place in the two large continental ice sheets, Greenland and Antarctica. Consequently, the projected sea level rise threatens low-lying countries like the Netherlands. The process of ‘climate-proofing’ the flood protection system of the country offers, however, new opportunities for innovative solutions, providing not only higher flood protection, but also possibilities for multifunctional land-use.
A comparative analyses of microstructures from Late Jurassic diamictic units, near Helmsdale, northeast Scotland and a Pleistocene diamicton from near Milton, southern Ontario, Canada – a differential diagnostic method of sediment typing using micromorphology
Authors: Menzies J. , Whiteman C.
Published: July 2016

Micromorphology is used to examine and compare a Late Jurassic diamictite from northeast Scotland with a Pleistocene diamict from southern Ontario, Canada in order to test if a statistical difference between diamicts can be recognized and used to separate differing types of diamicts/diamictites. The diamictites from Scotland have been ascribed to various depositional agencies occurring in several distinctly differing terrestrial and marine palaeoenvironments. In contrast, the Pleistocene diamicton is regarded as a subglacial till. Both diamicts appear remarkably similar visually and contain many corresponding features such as macrostructures, and exotic and fractured subangular to subrounded clasts. Micromorphology is used to re-examine these diamicts/diamictites at the microscopic level to detect if the palaeoenvironments within which they were deposited can be ascertained. In this paper a quantitative assessment of microstructures using micromorphology is developed. Comparative statistical analyses of these diamicts, using micromorphological features, reveals that the Jurassic diamictites are non-glacigenic, non-terrestrial and most likely deposited within a marine environment as a result of subaquatic debris mass movement, while, in contrast, the Pleistocene diamicts were most likely subglacial tectomicts deposited beneath the active base of the Laurentide Ice Sheet.
A new species of Lyelliceras (Ammonoidea, Lyelliceratidae) from the Albian (Lower Cretaceous) of France
Authors: Kennedy W.J.
Published: July 2016

A new lyelliceratid, Lyelliceras escragnollensis sp. nov., is described from the condensed Albian of Escragnolles (Var) and La Balme de Rencurel (Isère), as well as from the upper Lower or lower Upper Albian of Maurepaire (Aube), in France. The new species is precisely dated on the basis of a previous record from the lower Middle Albian Lyelliceras lyelli Subzone of the Hoplites dentatus Zone at Courcelles (Aube). It is regarded as a short-lived descendant of Lyelliceras pseudolyelli, and is characterised as a compressed species of the genus in which the inner ventrolateral tubercles are weak and apparently absent on the early phragmocone whorls, the outer ventrolateral clavi feeble, offset to opposite across the venter, the siphonal clavi being more numerous than the outer ventrolateral.
The late Maastrichtian cancellothyridid brachiopodTerebratulina chrysalis(Von Schlotheim, 1813) from the type Maastrichtian (southern Limburg, the Netherlands) and elsewhere in Europe
Authors: Simon E.
Published: July 2016

A complete growth series ofTerebratulina chrysalis(Von Schlotheim, 1813) collected from its type area near Maastricht (the Netherlands) is described and illustrated, with fully adult and gerontic specimens included so as to increase current knowledge of this taxon. Most specimens collected from other European outcrops are juveniles which are similar to juveniles from the type area near Maastricht. However, adults collected from the latter area and those from lower Maastrichtian white chalk deposits in northern Europe are quite different. These differences can be explained by palaeoenvironmental conditions and taphonomic processes.
Ammonite faunas from condensed Cenomanian-Turonian sections (‘Tourtias’) in southern Belgium and northern France
Authors: Kennedy W.J. , Amédro F. , Robaszynski F. , Jagt J.W.M.
Published: July 2016

In southern Belgium (Mons Basin and Tournai region) and northern France (area between Lille, Valenciennes and Maubeuge), condensed sequences have been referred to as ‘tourtias’ since the start of the nineteenth century. These levels correspond to a succession of trangressive systems tracts and generally appear as dark green, glauconitic and microconglomeratic facies. They are distributed all along the base of the more important transgressive systems tracts of the Cenomanian and basal Turonian from the Boulonnais (northwest France) to the Mons Basin (southern Belgium), through the Artois and Douaisis. Their age can now be determined more accurately by identification of their ammonite content, as housed in museums such as the Institut royal des Sciences naturelles de Belgique (IRScNB, Brussels) and the Musée d'Histoire naturelle de Lille (MHNL). Here material from the IRScNB collections is described, illustrated and discussed; specimens contained in the MHNL collections were described in a previous paper.
Valley downcutting in the Ardennes (W Europe): Interplay between tectonically triggered regressive erosion and climatic cyclicity
Authors: Demoulin A. , Becker A. , Rixhon G. , Braucher R. , Bourlès D. , Siame L.
Published: July 2016

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), cosmogenic10Be and26Al 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.
Combining quantitative field and modelling approaches towards understanding landscape dynamics: an evolution of ideas spanning Jef Vandenberghe's research career
Authors: Verstraeten G.
Published: July 2016

Geomorphology as a scientific discipline has underwent major developments since the mid 20th century. From its original descriptive nature aiming to understand landscape evolution, it developed towards a more process-based oriented discipline. To a large extent this evolution followed a quantitative approach whereby modelling becomes more and more important. A schism between applied or engineering geomorphology and system-based geomorphology aiming at understanding landscape change emerges in the 1950-1960's. Only at the end of the 20thcentury – early 21stcentury, integration of quantitative field-based approaches on longer term issues of landscape evolution with numerical modelling emerges. This is particularly true for the Holocene for which the importance of human impact on geomorphic processes and landforms became acknowledged. With respect to landscape evolution on much longer timescales, the development of tectonic geomorphology becomes apparent. In this paper, some evolution of ideas and trends within geomorphology with respect to understanding landscape dynamics are summarised and put into the career perspective of Jef Vandenberghe.
Borderline radiocarbon
Authors: van der Plicht J.
Published: July 2016

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.
Response to docetaxel and cisplatin induction chemotherapy of locally advanced head and neck squamous cell carcinoma: a multicenter, non-comparative, open-label interventional pilot study
Authors: Noronha V , Goswami C , Patil S , Joshi A , Patil V M , Murthy V , Arya S , Juvekar S , Goud S , Prabhash K
Published: July 2016

Background:

Docetaxel, cisplatin plus 5-fluorouracil is an efficacious induction regimen but is more toxic than cisplatin plus 5-fluorouracil. This study aimed to determine whether docetaxel and cisplatin without 5-fluorouracil maintains efficacy while decreasing toxicity.

Methods:

A multicenter non-comparative pilot study of locally advanced squamous cell carcinoma of the head and neck was performed. Patients received primary therapy comprising three cycles of 75 mg/m2 docetaxel and 75 mg/m2 cisplatin followed by concurrent chemoradiotherapy. The primary endpoint was the response rate to the docetaxel and cisplatin induction regimen.

Results:

A total of 26 patients were enrolled: of these, 23 (88.5 per cent) received all three docetaxel and cisplatin cycles. Common grade 3–4 adverse events were febrile neutropenia (19.2 per cent of patients), diarrhoea (19.2 per cent) and non-neutropenic infection (15.4 per cent). The overall response rate to docetaxel and cisplatin induction chemotherapy was 65.4 per cent. A total of 23 patients (88.5 per cent) subsequently received chemoradiotherapy with a median radiotherapy dose of 70 Gy. The response rate to chemoradiotherapy was 73 per cent. At a median follow up of 44 months, the 3-year progression-free survival and overall survival rates were 62 per cent and 69 per cent, respectively.

Conclusion:

Docetaxel and cisplatin induction chemotherapy is a feasible induction regimen with comparable efficacy to docetaxel, cisplatin and 5-fluorouracil induction chemotherapy.
Holonomy Groups Of Hypersurfaces
Authors: Kobayashi Shoshichi
Published: July 2016

The restricted homogeneous holonomy group of an n–dimensional Riemannian manifold is a connected closed subgroup of the proper orthogonal group SO(n) [1]. In this note we shall prove that the restricted homogeneous holonomy group of an n-dimensional compact hypersurface in the Euclidean space is actually the proper orthogonal group SO(n) itself. This gives a necessary (of course, not sufficient) condition for the imbedding of an n-dimensional compact Riemannian manifold into the (n +1)–dimensional Euclidean space.
Induced Connections and Imbedded Riemannian Spaces
Authors: Kobayashi Shoshichi
Published: July 2016

Let P be a principal fibre bundle over M with group G and with projection π : P → M. By definition of a principal fibre bundle, G acts on P on the right. We shall denote this transformation law by ρ
On the Dimension of Modules and Algebras, IV: Dimension of Residue Rings of Hereditary Rings
Authors: Eilenberg Samuel , Nagao Hirosi , Nakayama Tadasi
Published: July 2016

A ring (with unit element) Λ is called semi-primary if it contains a nilpotent two-sided ideal N such that the residue ring Γ = Λ/N is semi-simple (i.e. l.gl.dim Γ = r.gl.dim Γ = 0). N is then the (Jacobson) radical of Λ. Auslander [1] has shown that if Λ is semi-primary then

The common value is denoted by gl. dim Λ. On the other hand, for any ring Λ the following conditions are equivalent : (a) 1. gl. dim Λ ≦ 1, (b) each left ideal in Λ is projective, (c) every submodule of a projective left Λ-module is projective. Rings satisfying conditions (a)-(c) are called hereditary. For integral domains the notions of “hereditary ring” and “Dedekind ring” coincide.
Infinitesimal Holonomy Groups of Bundle Connections
Authors: Ozeki Hideki
Published: July 2016

In Introduction In differential geometry of linear connections, A. Nijenhuis has introduced the concepts of local holonomy group and infinitesimal holonomy group and obtained many interesting results [6].

The purpose of the present note is to generalize his results to the case of connections in arbitrary principal fiber bundles with Lie structure groups. The concept of local holonomy group can be immediately generalized and has been already utilized by S. Kobayashi [4]. Our main results are Theorems 4 and 5 on infinitesimal holonomy groups. The proofs depend on a little sharpened form of a theorem of Ambrose-Singer [1]. In the case of linear connections, our infinitesimal holonomy group coincides with that of Nijenhuis, as we shall show in Section 6.
On Boundary Values of an Analytic Transformation of a Circle into a Riemann Surface
Authors: Ohtsuka Makoto
Published: July 2016

Let f(z) be a nonconstant analytic transformation of the unit circle U : ∣z∣ < 1 into a Riemann surface ℜ. As an extension of a classical theorem of F. and M. Riesz, the author proved in Theorem 3.4 of [2] that if the image of U is relatively compact in ℜ and has universal covering surface of hyperbolic type, and if, at every point of a set on ∣z∣ = 1 of positive inner linear measure, there terminates a curve along which f(z) has limit, then the set of such limits has positive inner logarithmic capacity. This theorem was followed by the first proposition in Kuramochi [1], which asserts that, if ℜ has a null boundary and the image of U excludes a set of positive logarithmic capacity on ℜ and if, at every point of a set E on ∣z∣ = 1, there terminates a curve along which f(z) has limit in the union of a set of inner logarithmic capacity zero on ℜ and the boundary components of ℜ then the inner linear measure of E is zero.
Umbilical points on surfaces in RN
Authors: Enomoto Kazuyuki
Published: July 2016

Let ϕ: M → RN be an isometric imbedding of a compact, connected surface M into a Euclidean space RN. ψ is said to be umbilical at a point p of M if all principal curvatures are equal for any normal direction. It is known that if the Euler characteristic of M is not zero and N = 3, then ψ is umbilical at some point on M. In this paper we study umbilical points of surfaces of higher codimension. In Theorem 1, we show that if M is homeomorphic to either a 2-sphere or a 2-dimensional projective space and if the normal connection of ψ is flat, then ψ is umbilical at some point on M. In Section 2, we consider a surface M whose Gaussian curvature is positive constant. If the surface is compact and N = 3, Liebmann’s theorem says that it must be a round sphere. However, if N ≥ 4, the surface is not rigid: For any isometric imbedding Φ of R3 into R4 Φ(S2(r)) is a compact surface of constant positive Gaussian curvature 1/r2. We use Theorem 1 to show that if the normal connection of ψ is flat and the length of the mean curvature vector of ψ is constant, then ψ(M) is a round sphere in some R3 ⊂ RN. When N = 4, our conditions on ψ is satisfied if the mean curvature vector is parallel with respect to the normal connection. Our theorem fails if the surface is not compact, while the corresponding theorem holds locally for a surface with parallel mean curvature vector (See Remark (i) in Section 3).
Homogeneous vector bundles and stability
Authors: Kobayashi Shoshichi
Published: July 2016

In [5, 6, 7] I introduced the concept of Einstein-Hermitian vector bundle. Let E be a holomorphic vector bundle of rank r over a complex manifold M. An Hermitian structure h in E can be expressed, in terms of a local holomorphic frame field s1, …, sr of E, by a positive-definite Hermitian matrix function (hij) defined by
Homotopy groups of pullbacks of varieties
Authors: Sommese Andrew John , Ven A. van de
Published: July 2016

In [2, § 9] there is a general result of Fulton and Lazarsfeld relating the homotopy groups of a subvariety of in a certain range of dimensions with those of its pullback under a holomorphic map in the corresponding range of dimensions. It is asked in [2, § 10] whether here is a corresponding result with replaced by a general rational homogeneous manifold, Y, and with the range of dimensions alluded to above shifted by the ampleness of the holomorphic tangent bundle of Y in the sense of [4]. In this paper we use the techniques of [4, 5, 6, 7] to answer this question in the affirmative.
Imaginary bicyclic biquadratic fields with the real quadratic subfield of class-number one
Authors: Yokoi Hideo
Published: July 2016

It has been proved by A. Baker [1] and H. M. Stark [7] that there exist exactly 9 imaginary quadratic fields of class-number one. On the other hand, G.F. Gauss has conjectured that there exist infinitely many real quadratic fields of class-number one, and the conjecture is now still unsolved.
Ternary quadratic forms and Brandt matrices
Authors: Schulze-Pillot Rainer
Published: July 2016

In a recent paper [9] the author showed (among other results) estimates on the asymptotic behaviour of the representation numbers of positive definite integral ternary quadratic forms, in particular, that for n in a fixed square class tZ2 and lattices L, K in the same spinor genus one has . The main tool utilized for the proof was the theory of modular forms of weight 3/2, especially Shimura’s lifting from the space of cusp forms of weight 3/2 to the space of modular forms of weight 2.