bluuebunny/crossref_metadata_2025_split huggingface dataset:
A histological study of a femur ofPlagiosuchus, a Middle Triassic temnospondyl amphibian from southern Germany, using thin sections and micro-CT scanning
Authors: Konietzko-Meier D. , Schmitt A. 
Published: July 2016

AbstractThe histology of a femur ofPlagiosuchus, a Middle Triassic temnospondyl amphibian, is described on the basis of two supplementary methods: classic thin sectioning and micro-CT scanning. In addition, the effectiveness of high-resolution micro-CT scanning for histological analysis is assessed. A classic, mid-shaft thin section of the femur was prepared, but prior to slicing two micro-CT scans were made. One of these has an image stack of a total of 1,024 images in the horizontal plane and a slice thickness of 87.8 μm, so that the entire bone could be captured, while the second was at mid-shaft region only, yet with a higher resolution of 28.3 μm and an image stack of 787 images in the horizontal plane. The classic thin section shows a very small medullary region which is surrounded by a layer of endosteal bone. The thick cortex is highly porous with numerous large, mainly longitudinal, vascular canals arranged in layers. In the deepest cortex woven bone occurs and primary osteons had locally started to form (incipient fibro-lamellar bone), which gradually passes into parallel-fibred bone and more lamellar bone close to the outer surface. Remains of a Kastschenko line were identified, enabling a reconstruction of the entire growth record. Five Lines of Arrested Growth (LAG) could be counted. The micro-CT scan enabled observations of the ontogenetic growth stages and calculation of growth rate on the basis of a single specimen. The micro-CT scan permitted a reconstruction of the ontogenetic development and the exact deposition rate per annum. Moreover, at higher resolution the micro-CT scan revealed data on micro-anatomical characters, such as porosity and skeletochronology (growth mark count). In conclusion, micro-CT scans do provide an alternative in cases where thin sectioning of the original bone is not possible.
On the piscivorous behaviour of the Early Cretaceous amiiform neopterygian fishCalamopleurus cylindricusfrom the Santana Formation, northeast Brazil
Authors: Mulder E.W.A. 
Published: July 2016

AbstractA specimen of the Early Cretaceous amiiform fishCalamopleurus cylindricuswith stomach content is described from the Santana Formation, Brazil. The prey concerns a smaller conspecific individual. Until now, prey items documented forCalamopleurusalmost exclusively involved the aspidorhynchidVinctifer. On the basis of the present record it is suggested that the prey preference ofCalamopleuruswas less pronounced than previously assumed.
Dental macro- and microwear in Carinodens belgicus, a small mosasaur from the type Maastrichtian
Authors: Holwerda F.M. , Beatty B.L. , Schulp A.S. 
Published: July 2016

AbstractTeeth of the small durophagous mosasaur Carinodens belgicus are known from Maastrichtian Atlantic-Tethyan deposits worldwide. The peculiar dentition of Carinodens inspired debate and speculation on its dietary niche ever since its first description. In this contribution, we describe the macro- and microwear pattern in five well-preserved isolated teeth, allowing further and independent evaluation of aspects of feeding behaviour and diet. Macroscopically, wear is concentrated on the apex and mesiodistal sides. Microwear was mapped using Scanning Electron Microscopy at several magnifications and can be characterised as scratches and pits. Coarse scratches were found to be the most common and pits were found to be the least common feature. Scratch orientation is primarily along the mesiodistal plane or in the labiolingual plane with an angle of ~130°. These microwear features can be explained either by oral processing or passive abrasion by sediments or food. As scratch width only indicates the minimum width of the abrading particle, the material causing the wear here could have ranged from silica-based silts to larger abrasives. However, in this case, abrasion by sediments might not explain this wear because of the biocalcarenitic nature of the type Maastrichtian sediments; siliciclastics are virtually absent. Therefore it is more likely that hard food particles, such as benthic organisms with hard exoskeletons, caused the wear on the enamel of Carinodens, or Carinodens ventured out to more sandy areas to forage as well. The mesiodistal and labiolingual direction of the microwear scratches might suggest that Carinodens showed more complexity in the use of its teeth than simple grasping, and that a gripping and pulling motion during feeding similar to that employed by modern varanids may have been the cause.
New insights into the geological structure of the Netherlands; results of a detailed mapping project
Authors: Kombrink H. , Doornenbal J.C. , Duin E.J.T. , den Dulk M. , ten Veen J.H. , Witmans N. 
Published: July 2016

AbstractA five years geological mapping project, in which the Netherlands Continental Shelf has been re-examined using all publicly available data, resulted in an important update of the existing dataset. The stratigraphy of over 400 wells has been re-interpreted. New depth and thickness grids, based mainly on the interpretation of 3D seismic data have been produced for the most important stratigraphic intervals from Permian Upper Rotliegend to Neogene. New reservoir grids describe the top, base and thickness of 30 (potential) reservoir units in the area. In addition, the uncertainty related to interpretation and further processing of the data has been assessed. This resulted in maps displaying the standard deviation for the depth of the main stratigraphic intervals. Based on these results and the data already available for the onshore area, an updated structural element map was made for the Netherlands.
Reservoir characterisation of aquifers for direct heat production: Methodology and screening of the potential reservoirs for the Netherlands
Authors: Pluymaekers M.P.D. , Kramers L. , van Wees J.-D. , Kronimus A. , Nelskamp S. , Boxem T. , Bonté D. 
Published: July 2016

AbstractGeothermal low enthalpy heat in non-magmatic areas can be produced by pumping hot water from aquifers at large depth (>1 km). Key parameters for aquifer performance are temperature, depth, thickness and permeability. Geothermal exploration in the Netherlands can benefit considerably from the wealth of oil and gas data; in many cases hydrocarbon reservoirs form the lateral equivalent of geothermal aquifers. In the past decades subsurface oil and gas data have been used to develop 3D models of the subsurface structure. These models have been used as a starting point for the mapping of geothermal reservoir geometries and its properties. A workflow was developed to map aquifer properties on a regional scale. Transmissivity maps and underlying uncertainty have been obtained for 20 geothermal aquifers. Of particular importance is to take into account corrections for maximum burial depth and the assessment of uncertainties. The mapping of transmissivity and temperature shows favorable aquifer conditions in the northern part of the Netherlands (Rotliegend aquifers), while in the western and southern parts of the Netherlands aquifers of the Triassic and Upper Cretaceous / Jurassic have high prospectivity. Despite the high transmissivity of the Cenozoic aquifers, the limited depth and temperature reduce the prospective geothermal area significantly.The results show a considerable remaining uncertainty of transmissivity values, due to lack of data and heterogeneous spatial data distribution. In part these uncertainties may be significantly reduced by adding well test results and facies parameters for the map interpolation in future work. For underexplored areas this bears a significant risk, but it can also result in much higher flowrates than originally expected, representing an upside in project performance.
Towards a process-based model to predict dune erosion along the Dutch Wadden coast
Authors: Ruessink B.G. , Boers M. , van Geer P.F.C. , de Bakker A.T.M. , Pieterse A. , Grasso F. , de Winter R.C. 
Published: July 2016

AbstractAn equilibrium dune-erosion model is used every six years to assess the capability of the most seaward dune row on the Dutch Wadden islands to withstand a storm with a 1 in 10,000 probability for a given year. The present-day model is the culmination of numerous laboratory experiments with an initial cross-shore profile based on the central Netherlands coast. Large parts of the dune coast of the Wadden islands have substantially different dune and cross-shore profile characteristics than found along this central coast, related to the presence of tidal channels, ebb-tidal deltas, beach-plains and strong coastal curvature. This complicated coastal setting implies that the predictions of the dune-erosion model are sometimes doubtful; accordingly, a shift towards a process-based dune-erosion model has been proposed. A number of research findings based on recent laboratory and field studies highlight only few of the many challenges that need to be faced in order to develop and test such a model. Observations of turbulence beneath breaking waves indicate the need to include breaking-wave effects in sand transport equations, while current knowledge of infragravity waves, one of the main sand transporting mechanisms during severe storm conditions, is strongly challenged by laboratory and field observations on gently sloping beaches that are so typical of the Wadden islands. We argue that in-situ and remote-sensing field observations, laboratory experiments and numerical models need to be the pillars of Earth Scientific research in the Wadden Sea area to construct a meaningful process-based dune-erosion tool.
Stratigraphy of the upper Vijlen Member (Gulpen Formation; Maastrichtian) in northeast Belgium, the southeast Netherlands and the Aachen area (Germany), with special reference to belemnitellid cephalopods
Authors: Keutgen N. , Jagt J.W.M. , Felder P.J. , Jagt-Yazykova E.A. 
Published: July 2016

AbstractRecent studies have demonstrated the complex depositional history of the Vijlen Member (Gulpen Formation) in the Maastricht-Aachen-Liège area, on which synsedimentary tectonics had a profound impact, in conjunction with regressive and transgressive episodes, the oldest portion of this member being preserved only locally, within channel-like structures. Our reinterpretation of the Vijlen Member, here presented, is at variance with current belemnite stratigraphy. To account for incongruities, reworking of belemnites is here proposed as a typical feature during Vijlen Member deposition. A renewed study of belemnites on the basis of these new data suggests that intervals 4–6 of the Vijlen Member are of late Maastrichtian age. With respect to the mean values of populations ofBelemnitella juniorNowak andBelemnitella IwowensisNaidin, Vijlen Member intervals 4–5 are coeval with theSpyridoceramus tegulatus/Belemnitella juniorZone (sensu germanico), whereas at least the upper portion of interval 6 is correlatable with the basalTenuipteria argentea/Belemnitella juniorZone (sensu germanico). Although reworking of belemnites appears to have been a common feature, this cannot be properly substantiated without additional geochemical analyses of individual guards. For this reason, we refrain from proposing a biostratigraphic zonation of the Vijlen Member based on belemnites. Alternatively, scaphitid ammonites might be used to subdivide this member, because species such asAcanthoscaphites(Acanthoscaphites)tridens(Kner),A.(Euroscaphites)varians blaszkiewicziJagt, Kennedy & Machalski,Hoploscaphites constrictus(J. Sowerby),H. tenuistriatus(Kner) andHoploscaphitessp. have been recorded. The last-named taxon represents an interspecies hybrid between the North AmericanJeletzkytes dorfiLandman & Waage and an unidentified subspecies of the endemic European lineage ofH. constrictus, allowing correlation of the lower portion of Vijlen Member interval 6 with theHoploscaphites birkelundaeZone of the United States Western Interior.
The youngest Maastrichtian ‘true’ inoceramids from the Vijlen Member (Gulpen Formation) in northeast Belgium and the Aachen area (Germany)
Authors: Walaszczyk I. , Jagt J.W.M. , Keutgen N. 
Published: July 2016

AbstractThe youngest representatives of ‘true’ (= non-tegulated) inoceramid bivalves (Inoceramidae) are described from intervals 3-6 of the Vijlen Member (Gulpen Formation), of late early and early late Maastrichtian age, as exposed at quarries and temporary sections in northeast Belgium (CPL SA-Haccourt and CBR-Lixhe quarries) and the Aachen area (Germany), i.e. the extended type area of the Maastrichtian Stage. In total, twelve taxa are recognised from levels which are correlative with the Calcaire àBaculitesof Manche (France), as well as with the Tercis les Bains section in southwest France, the Wisła (Vistula) River sections (central Poland) and the Western Interior of the United States. Associated cephalopods allow a detailed correlation between biozones based on those groups and on inoceramid bivalves.
Geo(Im)pulse An unexpected fossil crinoid from the ‘Kor en Bot’ trawling trips on the Oosterschelde (Zeeland, the Netherlands)
Authors: Jagt J.W.M. , Reumer J.W.F. 
Published: July 2016

AbstractDuring 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.
From river valley to estuary: the evolution of the Rhine mouth in the early to middle Holocene (western Netherlands, Rhine-Meuse delta)
Authors: Hijma M.P. , Cohen K.M. , Hoffmann G. , Van der Spek A.J.F. , Stouthamer E. 
Published: July 2016

AbstractThe aim of this paper is to reconstruct the evolution of the early to middle Holocene Rhine-Meuse river mouths in the western Netherlands and to understand the observed spatial and temporal changes in facies. This is achieved by constructing three delta wide cross-sections using a newly accumulated database with thousands of core descriptions and cone penetration test results, together with a large set of pollen/diatom analyses and OSL/14C-dates. Most of the studied deposits accumulated in the fluvial-to-marine transition zone, a highly complex area due to the interaction of terrestrial and marine processes. Understanding how the facies change within this zone, is necessary to make correct palaeogeographic interpretations.We find a well preserved early to middle Holocene coastal prism resting on lowstand valley floors. Aggradation started after 9 ka cal BP as a result of rapid sea-level rise. Around 8 ka most parts of the study area were permanently flooded and under tidal influence. After 8 ka a bay-head delta was formed near Delft, meaning that little sand could reach the North Sea. Several subsequent avulsions resulted in a shift from the constantly retreating Rhine river mouth to the north. When after 6.5 ka the most northerly river course was formed (Oude Rijn), the central part of the palaeovalley was quickly transgressed and transformed into a large tidal basin. Shortly before 6 ka retrogradation of the coastline halted and tidal inlets began to close, marking the end of the early-middle Holocene transgression.This paper describes the transition from a fluvial valley to an estuary in unprecedented detail and enables more precise palaeo-reconstructions, evaluation of relative importance of fluvial and coastal processes in rapid transgressed river mouths, and more accurate sediment-budget calculations. The described and well illustrated (changes in) facies are coupled to lithogenetic units. This will aid detailed palaeogeographic interpretations from sedimentary successions, not only in the Netherlands, but also in other estuarine and deltaic regions.
Connecting the Chalk Group of the Campine Basin to the dinoflagellate cyst biostratigraphy of the Campanian to Danian in borehole Meer (northern Belgium)
Authors: Slimani H. , Louwye S. , Dusar M. , Lagrou D. 
Published: July 2016

AbstractA palynological study of the Chalk Group (Campanian-Danian) in the Meer borehole (northern Belgium), which penetrated the thickest succession known in the Campine Basin, has revealed diverse, well-preserved organic-walled dinoflagellate cyst assemblages. The succession contains numerous chronostratigraphically significant dinocyst events, which are based mainly on the highest consistent occurrences of index species. At least 35 bio-events have enabled a subdivision into nine intervals, at stage or substage level, within the Campanian to Danian interval, as based on comparison with coeval assemblages elsewhere in northwest Europe, inclusive of stratotypes of stages and stage boundaries. Bio-events allow correlation of the section studied with the CampanianExochosphaeridium? masureae, Areoligera coronataandSamlandia mayizones, the MaastrichtianPervosphaeridium tubuloaculeatum, Deflandrea galeataandHystrichostrogylon coninckiizones, and the DanianDamassadinium californicumZone. In addition, a correlation with other zonal schemes for the southern North Sea Basin and with conventional northwest European belemnite zones is presented. Comparisons with Boreal and Tethyan realms confirm that most bio-events may also be useful for interregional and global correlation. The Campanian-Danian dinocyst biostratigraphy of the Meer borehole is put alongside geophysical well logs and an ecozonation, in order to check the validity of lithostratigraphical correlations across the Campine Basin. This first, detailed correlation attempt shows that sensitivities to facies change associated with differences in accommodation space and sediment supply appear to be at the base of slight, yet consistent, shifts between the local lithological succession and the standard lithostratigraphical scheme of the Maastricht type area.
On the taphonomy of the late Maastrichtian (Late Cretaceous) marine turtle Allopleuron hofmanni
Authors: Janssen R. , van Baal R.R. , Schulp A.S. 
Published: July 2016

AbstractAn exhaustive screening of public collections containing remains of the latest Cretaceous (late Maastrichtian) marine turtle Allopleuron hofmanni (Gray, 1831) from the type area of the Maastrichtian Stage (southeast Netherlands, northeast Belgium) shows the available material to represent almost exclusively adult individuals. The various skeletal elements are not preserved in proportionally equal abundance, with portions of carapace, pectoral girdle, cranium and mandible overrepresented. These observations can be explained by population characteristics and taphonomic factors. During the late Maastrichtian, while hatchlings and juveniles in all likelihood lived and fed elsewhere, extensive seagrass meadows might have supported a population of only adult marine turtles.
Belemnite-based strontium, carbon and oxygen isotope stratigraphy of the type area of the Maastrichtian Stage
Authors: Vonhof H.B. , Jagt J.W.M. , Immenhauser A. , Smit J. , van den Berg Y.W. , Saher M. , Keutgen N. , Reijmer J.J.G. 
Published: July 2016

AbstractBelemnitellid cephalopods from the Maastrichtian stratotype area (southeast Netherlands) are shown to be comparatively well preserved. Although partial diagenetic alteration has been observed, micromilling techniques have permitted the extraction of pristine belemnite calcite, suitable for the reconstruction of strontium (Sr), oxygen (O) and carbon (C) isotope variation of Maastrichtian seawater. A distinct Sr isotope pattern in the Maastricht record can be matched stratigraphically with records from Hemmoor (northern Germany), El Kef (Tunisia) and ODP site 690 (Maud Rise, Antarctica), leading to a new chemostratigraphical age model for the Maastrichtian stratotype section. Our data improve currently applied strontium isotope stratigraphical reference curves by revealing an Sr isotope inflection pattern near the lower/upper Maastrichtian boundary that is a potentially diagnostic feature for intra-Maastrichtian stratigraphical correlation between distant sections. Belemnites further show significant stratigraphical oxygen isotope variation through the Maastrichtian. We interpret this variation to have resulted from palaeoceanographic reorganisations in the Atlantic Ocean during this time interval.
Unravelling the depositional environment of the Archaean Rajkharsawan conglomerate (Jharkhand, eastern India)
Authors: van Loon A.J. , Mazumder R. , De S. 
Published: July 2016

AbstractLarge conglomerate lenses occur in a fine-grained siliciclastic succession of the Singhbhum craton, eastern India. They overlie an Archaean orthogneiss, from which they are separated by a palaeosol. Neither the conglomerates nor the directly overlying rocks have been dated, but the conglomerate unit is assumed to have also an Archaean age. The conglomerate lenses occur within a succession of pelitic and mafic schists, and the depositional environment of this conglomerate/schist unit had not been clarified thus far. On the basis of a combination of the vertical and horizontal distribution of the conglomerates, their stratigraphic position and analysis of their sedimentological characteristics and the sedimentological context, it is concluded that the succession must have developed in a fluvial lowland environment where volcanic input contributed significantly to the sediment accumulation.
Multi-proxy analysis: a reflection on essence and potential pitfalls
Authors: Vandenberghe J. 
Published: July 2016

AbstractMulti-disciplinarity and multi-proxy approaches are necessary to understand the processes in complex earth systems. However, unlimited and uncontrolled multi-proxy-correlations may be risky. A number of case studies illustrate the potential pitfalls when the processes that drive the individual proxies have no common causal significance or dating is not precise enough. Crossing thresholds at different levels and delay times may also be factors that hamper direct correlations of proxies. Multi-proxy analysis of the intrinsic relationships between proxies in a system is the primary task before any correlation should be made.