bluuebunny/crossref_metadata_2025_split huggingface dataset:
The groundwater quality of Aruba, Bonaire and Curaçao: a hydrogeochemical study
Authors: van Sambeek M.H.G. , Eggenkamp H.G.M. , Vissers M.J.M. 
Published: April 2016

AbstractThe Groundwater resources on the Caribbean Islands of Aruba, Bonaire and Curaçao are limited and of poor quality. The groundwater of the islands is brackish, due to both seawater mixing and the semi-arid climate of the islands. Two hundred and thirty water samples were collected to relate chemical variations in the groundwater of the three islands to the underlying differences in geology, and to define the natural versus anthropogenic influences. Both the chemical and isotopic (δ180, δD, and δ37Cl) compositions of samples were determined.Several geochemical processes are recognised in the chemistry of the groundwater samples. The most important processes are calcite dissolution, cation exchange, silicate weathering and potassium fixation. In (sub)urban areas anthropogenic influences affect the groundwater quality: high nitrate concentrations were measured. Infiltrating domestic and agricultural (waste)water replenishes the aquifer, and has a desalinization effect on the groundwater quality. This phenomenon is primarily seen on Curaçao, the most populated island.Oxygen and hydrogen isotopie compositions of groundwaters from Curaçao and Bonaire show that the samples are either meteoric water, or are affected by evaporation or seawater mixing. No distinction could be made between the last two processes. Only a few samples were measured for the Cl-isotope composition; all showed that no physical processes have taken place.
Aruba - a geochemical baseline study
Authors: van den Oever F. 
Published: April 2016

AbstractA stream-sediment survey was carried out for the island of Aruba. Concentrations in stream sediments represent the abundance of chemical elements in the drainage basins. A geochemical atlas was created from the collected data and natural background values were established. Cluster analysis and pattern recognition techniques were used to gain a better understanding of the data set.Two cluster models were selected to study the various geochemical controls on the sediments and to establish a spatial basis of environmental-quality settings for the development of future environmental policies. The first cluster model was suitable to recognise in some detail the reflection of the geology on the geochemistry of the stream sediments. The second, coarser cluster model stressed the importance to distinguish between the two main lithological units of the island when instituting natural background values. Not one uniform value per element is valid, but the value depends on the lithology.
The semi-arid environment of Curaçao: a geochemical soil survey
Authors: de Vries A.J. 
Published: April 2016

AbstractA geochemical soil survey was carried out on the island of Curaçao in October 1992 as part of an overall geochemical characterisation of the three Leeward islands of the Netherlands Antilles. The aim of this soil survey was to provide systematic geochemical data of the rural soils of Curaçao for characterisation, geochemical mapping and environmental application. A total of 122 samples was collected from the topsoils (upper 0.1 m) within a rectangular grid (2 km2). All samples were sieved to a grain size of < 2 mm and analysed for 24 elements by ICP-AES, after decomposition with hot aqua regia. A small, selected set of soil samples was subjected to a more extensive study of soil properties.It appears from statistical data interpretation of the chemical compositions with techniques like non-linear mapping and cluster analysis that the topsoils of Curaçao can be divided into six homogeneous groups (soil types) with contrasting chemical signatures. Labelled according to their dominant geology, soil process or most striking characteristic, these soil types are defined as follows: sandy limestone soil type, Midden Curaçao soil type, arid/calcareous soil type, basalt West soil type, agriculture-influenced soil type, and the basalt East soil type.Geochemical contour maps were made that provide a basis for environmental issues on the island. Finally, background levels (baseline data) were derived from the chemical soil composition of several elements, taking into consideration the correlation with the Fe or Al content of these soils. The defined baselines can be used to establish background values for future soil surveys.
Abiotic landscape and vegetation patterns in the Netherlands during the Weichselian Late Glacial
Authors: Hoek W.Z. 
Published: April 2016

AbstractThe Late Glacial landscape of the Netherlands was a landscape with changing geomorphology and vegetation. Glacial, eolian and fluvial processes in the time before the Late Glacial initially had formed the main landscape types that still existed during the Late Glacial. In these landscape types, geomorphological processes persisted, particularly during intervals when the vegetation cover was discontinuous. Vegetation development initiated soil formation and stabilised the substratum. On the other hand, the abiotic landscape influenced vegetation development, and particularly vegetation patterns.The Late Glacial vegetation patterns, changing in time, have been reconstructed on the basis of a palynological database containing the data from over 250 pollen diagrams from the Netherlands. Patterns of vegetation and abiotic landscape appear to compare to each other in many instances, indicating the close interrelationship between vegetation and the abiotic landscape.
Rifting processes in NW-Germany and the German North Sea Sector
Authors: Kockel F. 
Published: April 2016

AbstractSince the beginning of the development of the North German Basin in Stephanien to Early Rotliegend times, rifting played a major role. Nearly all structures in NW-Germany and the German North Sea - (more than 800) - salt diapirs, grabens, inverted grabens and inversion structures - are genetically related to rifting. Today, the rifting periods are well dated. We find signs of dilatation at all times except from the Late Aptian to the end of the Turonian. To the contrary, the period of the Coniacian and Santonian, lasting only five million years was a time of compression, transpression, crustal shortening and inversion. Rifting activities decreased notably after inversion in Late Cretaceous times. Tertiary movements concentrated on a limited number of major, long existing lineaments. Seismically today NW-Germany and the German North Sea sector is one of the quietest regions in Central Europe.
Characterisation and correlation of Tertiary seismostratigraphic units in the Roer Valley Graben
Authors: Verbeek J.W. , de Leeuw C.S. , Parker N. , Wong Th.E. 
Published: April 2016

AbstractWithin the Cenozoic sedimentary section of the Roer Valley Graben ten seismostratigraphic units have been identified. They are closely related to the lithological framework which makes it possible to recognize diem also on well logs in this region. The Lower Tertiary seismic units, representing mainly marine sediments, have a uniform development mat can be correlated over large distances into the German part of the Roer Valley Graben. The marine to continental Upper Tertiary and Quaternary seismic units display a more complex development due to lateral facies changes (including prograding delta systems) and rift tectonics.
Facies interpretation from well logs applied to the Tertiary Lower Rhine Basin fill
Authors: Klett M. , Eichhorst F. , Schäfer A. 
Published: April 2016

AbstractThe Cenozoic fill of the Lower Rhine Basin is investigated with data from industry wells and open-cast mines on lignite coal. The geophysical logs of digitised well data are used to calculate lithofacies logs with a newly developed technique. The lithofacies logs allow the interpretation of shallow marine and continental environments in a sequence stratigraphie approach. In addition, base level analysis with both the lithofacies logs and the geophysical logs provide a stratigraphical frame for environment interpretation, modelling, and simulation.
Biostratigraphy and paleoecology of continental Tertiary vertebrate faunas in the Lower Rhine Embayment (NW-Germany)
Authors: Mörs Th. 
Published: April 2016

AbstractThis paper discusses the faunal content, the mammal biostratigraphy, and the environmental ecology of three important continental Tertiary vertebrate faunas from the Lower Rhine Embayment. The sites investigated are Rott (MP 30, Late Oligocene), Hambach 6C (MN 5, Middle Miocene), Frechen and Hambach 11 (both MN 16, Late Pliocene). Comparative analysis of the entire faunas shows the assemblages to exhibit many conformities in their general composition, presumably resulting from their preference for wet lowlands. It appears that very similar environmental conditions for vertebrates reoccurred during at least 20 Ma although the sites are located in a tectonically active region with high subsidence rates. Differences in the faunal composition are partly due to local differences in the depositional environment of the sites: lake deposits at the margin of the embayment (Rott), coal swamp and estuarine conditions in the centre of the embayment (Hambach 6C), and flood plain environments with small rivulets (Frechen and Hambach 11). The composition of the faunal assemblages (diversity and taxonomy) also documents faunal turnovers with extinctions and immigrations (Oligocene/Miocene and postMiddle Miocene), as a result of changing climate conditions.Additional vertebrate faunal data were retrieved from two new assemblages collected from younger strata at the Hambach mine (Hambach 11C and 14). They are important for the understanding of the Plio-Pleistocene transition in the southern part of the Lower Rhine Embayment and for correlating depositional sequences in the Dutch/German borderland.
Facies and paleogeography of the Tertiary of the Lower Rhine Basin - sedimentary versus climatic control
Authors: Utescher T. , Mosbrugger V. , Ashraf A.R. 
Published: April 2016

AbstractBased on recent studies, the impact of global sea-level and climate change on the paleogeographic and sedimentary evolution of the Tertiary of the Lower Rhine Basin is analysed. It is shown that major changes in global climate and sea-level, such as the high-stand during the Middle Miocene climate optimum, the extreme low-stands near the base of the Tortonian and within the Messinian, are clearly reflected in the sedimentary succession. Continental climate curves, as reconstructed from Tertiary macrofloras of the Lower Rhine Basin, can be correlated with the marine, long-term isotope record. As shown by the analyses, a warm and humid climate with mean annual temperatures above 13°C and mean annual precipitation not below 1000 mm, persisted throughout the Late Miocene to Early Pliocene. Continental, high-resolution, climate data show that Late Miocene alternations of lignites and elastics are rather caused by tectonic and sedimentary processes (such as the repeated migration of the river system) than by major climate changes.
Stratigraphy and paleoecology of the Late Pliocene and Early Pleistocene in the open-cast mine Hambach (Lower Rhine Basin)
Authors: Heumann G. , Litt Th. 
Published: April 2016

AbstractMore than 400 samples for paleobotanical and sedimentological investigations were collected from Late Pliocene and earliest Pleistocene beds in the open-cast lignite mine Hambach. They were analysed to obtain information about the paleoecology and paleoclimate of this time interval. The sedimentation type changed from a high-energy meandering fluvial system to floodplain, swamp and oxbow lake sedimentation. The typical Tertiary floral elements decreased with the onset of increasingly cooler climatic conditions and disappeared at the beginning of the Pleistocene to be substituted by a impoverished and coldadapted flora. These combined litho- and biostratigraphic investigations led to an improved and reproducible separation of Late Pliocene from Early Pleistocene deposits.
Recent movement pattern of the Lower Rhine Embayment from tilt, gravity and GPS data
Authors: Campbell J. , Kümpel H.-J. , Fabian M. , Fischer D. , Görres B. , Keysers Ch.J. , Lehmann K. 
Published: April 2016

AbstractAs part of the activities of the Collaborative Research Centre ‘SFB 350’, measurements of geodetic and geodynamic changes in the area of the Lower Rhine Embayment and the Rhenish Shield are being performed at different scales in space and time. Continuous borehole tilt measurements and repeated microgravimetric surveys yield information on the local stability of the ground and changes in horizontal gravity gradients that are both dominated by seasonal fluctuations. Results of more than seven years of regular GPS campaigns are discussed in terms of vertical and horizontal point motions. The most prominent motions are man-induced effects occurring in or near the browncoal mining areas, where groundwater withdrawal produces subsidence of up to 2.2 cm/y in the area under investigation. Horizontal and vertical motions at other GPS points are smaller by one order of magnitude and in most cases are only marginally detectable. The eastward motion of two points in the Bergisches Land and the westward motion of two points in the Eifel near the Belgian border may be interpreted as a result of the ongoing extension of the Cenozoic rift system in the western part of the Eurasian plate.
Kinematic subsidence modelling of the Lower Rhine Basin
Authors: Jentzsch T. , Siehl A. 
Published: April 2016

AbstractKinematic geological models can greatly enhance our understanding of the interaction and timing of processes involved in the formation of sedimentary basins. The prototype tool for the calculation and visualisation of such models presented here is aimed at studying subsidence rates and patterns at basin scale: A backstripping algorithm is applied to a geometrical 3D-model consisting of prismatic volumes, constructed from an initial set of stacked triangulated surfaces. As a result, we obtain a collection of palinspastically restored volumes for each timestep of basin evolution. The backstripped volumes of each layer are then arranged within a timescene, and the set of timescenes collected as a hierarchical timetree. By interpolating between succeeding key-frames, the subsidence history of the basin can be viewed as an interactive, continuous animation. The approach is illustrated using a high-resolution dataset from the German part of the Cenozoic Lower Rhine Basin.
Towards a balanced 3D kinematic model of a faulted domain - the Bergheim open pit mine, Lower Rhine Basin
Authors: Thomsen A. , Siehl A. 
Published: April 2016

AbstractIn the context of the investigation of the sedimentary and structural evolution of the Cenozoic Lower Rhine Basin, the construction of a volume-balanced kinematic model of a small faulted domain with detailed spatial information on strata and fault geometry from a set of parallel geological sections is under development. A 3D geometry model is built that allows for relative movements of blocks at fault surfaces. Rouby’s method of restoration in the map plane is used to determine horizontal displacement fields. The 3D and 3D(t) geometry models are supported by the object-oriented geometry database tool GeoToolKit for storage and retrieval of selected parts of the model using queries referring to spatial and temporal criteria, while visualization is based on key frame technique.
Global correlation of long Quaternary fluvial sequences: a review of baseline knowledge and possible methods and criteria for establishing a database
Authors: Bridgland D.R. , Maddy D. 
Published: April 2016

AbstractFluvial sequences, particularly major terrace staircases, represent potential archives of palaeoclimatic fluctuation during the Quaternary. Such sequences can span much if not all of the Quaternary and, provided that dating is possible, can serve as stratigraphical frameworks for correlation with evidence from other depositional environments. In particular, they can provide a terrestrial lithostratigraphical framework that can be correlated with the global marine oxygen isotope record. Fluvial lithos-tratigraphical frameworks also provide important contexts for records of faunal evolution and human occupation, the latter largely determined from the occurrence of artefacts in fluviatile sediments.This paper announces a new project within the International Geological Correlation Programme, devoted to fluvial sequences (IGCP 449 ‘Global Correlation of Late Cenozoic fluvial deposits’). It attempts to summarize existing baseline knowledge at the outset of the project and outlines the proposed methods and criteria for establishing a database of fluvial sequences.
Correlation of English and German Middle Pleistocene fluvial sequences based on mammalian biostratigraphy
Authors: Schreve D.C. , Bridgland D.R. 
Published: April 2016

AbstractIn this paper interglacial mammalian assemblages from key Middle Pleistocene fluvial sites in Germany are compared to Mammal Assemblage-Zones (MAZs) recently established in the post-Anglian/Elsterian sequence of the Lower Thames, U.K. It is believed that four separate interglacials are represented by the Lower Thames MAZs, correlated with oxygen isotope stages (OIS) 11, 9, 7 and substage 5e (although the last of these is Late Pleistocene). Nowhere in Germany can a full sequence of these interglacials be identified from mammalian evidence in a single terrace staircase, as is the case in the Lower Thames, although further research on the Wipper terraces at Bilzingsleben may identify such a sequence. It is also possible that the sequence of overlapping fluvial channels in the lignite mine at Schöningen will eventually produce a comparable mammalian story. Excellent correspondence has been recognized between the mammalian assemblages at Steinheim an der Murr and Bilzingsleben II and the Swanscombe MAZ from the Thames. These three sites are attributed to the Hoxnian/Holsteinian interglacial and are thought to correlate with OIS 11. Close comparison can also be made between the mammalian sequence from the celebrated travertine locality at Weimar-Ehringsdorf and two separate MAZs from Aveley, in the Thames, attributed to separate substages of OIS 7. An equivalent to the Purfleet MAZ of the Thames, which is believed to correlate with OIS 9, has yet to be identified in Germany.
Holocene fluvial response to climate change and human activities; Burgundy, France.
Authors: Straffin E.C. , Blum M.D. 
Published: April 2016

AbstractAlluvial deposits of the Loire/Arroux trunk/tributary system record distinct, synchronous episodes of regional fluvial adjustment. Changes in facies and depositional style through time can be interpreted with a modern analogue model that relates vegetative cover/human influence with sediment supply, and modes of atmospheric circulation with the paths and styles of storms that drive variable discharge regimes across western Europe.Zonal atmospheric circulation results in a Mediterranean style climate over southern Burgundy, producing dry conditions punctuated by infrequent, large floods. Episodic overbank sedimentation and the burial of thin paleosols in sandy overbank facies is indicative of this style of fluvial activity, ca 1300 years BP. Humans may have increased the available volume of fine grained sediment at this times through increased agricultural activity along valley axes, however facies match that expected from a ‘flashy’ discharge regime.In contrast, meridional circulation patterns result in a maritime style climate over southern Burgundy, with the intrusion of storms, moist conditions and frequent, moderate magnitude discharges. Wide, deep channels, thick channel facies and thin overbank facies are indicative of this style of fluvial activity, recorded in deposits dating to ca 4050 to 3200 years BP. Strong meridional conditions and extreme climatic variability during the Little Ice Age resulted in very large discharges that straightened and widened channels, while scouring and obscuring older terraces (ca 500 years BP). Deposition over the last two centuries is related to increasingly zonal circulation and infrequent, large (over-bank) floods. Changes in fluvial dynamics over the last 300 years can be attributed primarily to climatic control, as there has been very little change in land-use over that period.
Young tectonic and halokinetic movements in the North-German-Basin: its effect on formation of modern rivers and surface morphology
Authors: Sirocko F. , Szeder T. , Seelos C. , Lehne R. , Rein B. , Schneider W.M. , Dimke M. 
Published: April 2016

AbstractField mapping of fluvial terraces, aerial photographs, ground penetrating radar and seismic data from gas and oil exploration were used at four different locations to detect young tectonic and halokinetic movements in the North-German-Basin.i) The course of the Rivers Weser and Aller follow precisely a shallow Tertiary graben on the northwestern flank of the Verden salt diapir. Recent local depressions and vegetation anomalies on the alluvial plain have the same orientation as the strike direction of the faults at subsurface depth. Apparently, the river follows tectonic lines, and thus the river sediments can be used for the interpretation of recent crustal movements.ii) The Wedehof diapir, in contrast, is topped by a local topographic high which follows exactly the shape of the underlying salt. Either the diapir formed an obstacle for the advance of the continental glaciers or one has to assume halokinetic uplift of more than 50 m during the post-Saalian Pleistocene. Either way, the Wedehof diapir shows control of the modern surface morphology by halokinesis.iii) The course of the river Hunte, in contrast, outside the area of salt diapirism, shows anomalies of incision and terrace width over a local updoming caused by tectonic inversion of distinct blocks in the basin. The confluence of several tributaries of the Hunte lies exactly over the updoming of Barnstorf. Thus, the rivers do not avoid the local high, but focus in this area, which is characterised by a graben on top of the domestructure, as visible in seismic profiles. Again, tectonism controls river development.iv) The last case study is from Lake Plön, where seismic profiles reveal that linear shorelines of the lake parallel the flanks of two local graben structures of Tertiary age. It is apparent that the Weichselian glaciers that formed the lake and the surrounding moraines interacted with the existing grabens.The Tertiary morphology in the North German basin was apparently draped by Quaternary glacial deposits, but rivers and lakes that dominate the topography of the modern landscape still reflect the geodynamic centers of Tertiary tectonism and halokinesis. Faults from the depth of the Tertiary penetrate the Quaternary strata and allow upward fluid migration, which becomes visible on aerial photographs as linear vegetation anomalies.
Geological processes and the management of groundwater resources in coastal areas
Authors: Kooi H. , Groen J. 
Published: April 2016

AbstractIn this contribution, a case is made for the significance of sedimentation and sea-level change for groundwater management of coastal areas. In groundwater practice these geological processes are rarely considered. The role of sediment loading in causing anomalous fluid pressures and flow fields in relatively shallow aquifer systems is discussed and illustrated via both case studies and generic modelling studies. The role of sea-level changes in controlling current salinity distributions is discussed likewise. Central in the discussion is the concept of memory of groundwater systems, which provides the basic reason why processes that were operative in the geological past are still of relevance today. It is argued and shown that awareness and knowledge of the influence of sediment loading and sea level change on current hydrological conditions can lead to improved characterization of the distribution of hydraulic parameters and of the distribution of water quality in coastal areas. This improved characterization, in turn, serves to enhance the validity of impact assessment studies for the long-term development and management of those areas.