Clemenceau, the prime minister of France in the final stages of World War I, is reported to have said, “War is much too serious a thing to be left to the military”. Along these lines, one might say that “Climate change is much too serious to be left to climate scientists”. The point being that the views of technical specialists may be very important when a nation’s future is at stake, but that a purely technical perspective is too limited to decide on the best course of action. Leaving the issue of climate change, or war for that matter, solely to politicians is not wise either. Far too much is at stake for humanity as a whole to either accept uncritically or, alternatively, reject out-of-hand the doomsday message in Al Gore’s An inconvenient truth. This movie presents a dramatic view of the potential impact of climate change on our environment and hence human society.

Acquiring conventional 3 km towed streamer data along a 2D profile in the North of Shetland (UK) enables us to use the local Radon-attributes within the context of depth processing methodology for accurate delineation of volcanic units and imaging beneath high-velocity layers. The objective is to map the radially-dipping structure of the Erlend pluton and to investigate the potential existence of relatively soft Cretaceous sediments underneath volcanic units. Success in the Erlend Volcano study requires strict attention to the separation between different groups of events. The crucial point is the generalized discrete Radon transform formulated in terms of local wavefront (dip and curvature) characteristics. This transform is utilized during pre-CMP processing and migration to minimize event-coupling artefacts. These artefacts represent cross-talk energy between various wave modes and include the unwanted part of the wavefield. We show how to produce detailed subsurface images within the region of interest (exploration prospect only) by applying the closely tied processes of prestack event enhancement and separation, well-driven time processing for velocity model building, and final event-based prestack depth imaging. Results show enhanced structural detail and good continuity of principal volcanic units and deeper reflections, suggesting a faulted 0.6 – 0.9 km thick layer of Cretaceous sediments in the proximity of well 209/09-1. Our interpretation complements existing low-resolution geophysical models inferred from gravity and wide-angle seismic data alone.

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

This special issue contains the papers presented during the 2004 DEUQUA meeting. The papers provide an overview of recently carried out Quaternary geological studies on different aspects of the river Rhine system. The introductory paper follows the pathway of the Rhine downstream from its source in the Swiss Alps to the delta in the Netherlands. Along this route geological and geographical factors determine the regional subdivisions of the river: the Alps, the Upper Rhine Graben, the Rhenish Massif, and the Lower Rhine Embayment as part of the southern North Sea Basin. Each of these regions can be typified by a characteristic geological evolution.

New evidence from heavy-mineral analyses provides an improved lithostratigraphy and insight in the Quaternary evolution of the Rhine in the Upper Rhine Graben. The Plio-Pleistocene transition is determined by a palaeomagnetic study. The same paper emphasis on the impact of climate change on the composition of the magneto-mineralogy. Pollen analytical results show a complex interrelationship of a number of Middle Pleistocene interglacial periods in the northern part the Upper Rhine Graben. In the same area geomorphological analysis demonstrates a clear influence of tectonics on the preservation of fluvial terrace accumulations. A detailed pollen analytical study on the Late Glacial and Holocene development of the Rhine in the northern Upper Rhine Graben discusses the relation between vegetation cover and river behaviour. Finally, two papers from the Lower Rhine Embayment discuss a revised provenance based lithostratigraphy and its implications for understanding the fluvial history.

The Earth’ climate is a complex system consisting of the atmosphere, the ocean and the land surface. This system receives energy from the sun. Latitudinal variations in insolation and the rotation of the Earth lead to a complex turbulent geophysical flow which induces important transports of heat and mass. Part of the solar radiation is reflected, the rest is radiated as long wave radiation. The radiative balance is complicated by atmospheric water vapour and other trace gases, clouds, heat transport and other factors.

The Late Pleistocene Wijchen Member (WM) and its informal stratigraphic precursors have been recognized for decades in the Rhine-Meuse Valley of the Netherlands. Although the WM marks the top of the Kreftenheye Formation (KF) at the boundary between Pleistocene and Holocene lithofacies and provides a confining bed for the regional alluvial aquifer, significant issues remain regarding WM depositional environment and processes of sedimentation. Regional WM chronology suggests a time-transgressive, millennium scale response of the Rhine River to Lateglacial climate oscillations. This paper compares interpretations of sedimentation process, stratigraphic pattern, and paleoenvironmental significance to prevailing viewpoints on the WM mode of origin.

A flood basin in the Over Betuwe between the channel belts of the Neder Rijn and River Waal is investigated to characterize WM stratigraphy. The KF braided stream deposits (Kb) form a regionally extensive sandy to gravelly lithofacies. As Kb aggradation ceased, fluvial channels incised into local braid plain swales. The WM was deposited during episodes of fluvial activity as a suspended load mud drape across segments of the abandoned braid plain. The WM is a gray silty lithofacies that also contains local admixtures of sand. Explanations for the origin of the sand admixed into the mud include variability in hydrodynamic load across the flood plain, eolian mixing, and/or biogenic mixing. In the study area, eolian deposition of sand onto a wet flood plain surface is the most probable cause for the admixed sand fraction. Pedogenesis of the WM in the study area is limited to gleying under reduced wetland conditions and the development of organic rich vegetation horizons that formed on top of relatively unaltered fluvial strata. Similar reduced soil properties and limited pedogenic development occur downdip to the present coast, but updip of the study area, the WM is the parent material for poorly drained to well drained and oxidized profiles that range from Entisols to weakly expressed Alfisols.

The presence of pumice granules in Kb deposits of the study area indicate that channel belt deposition continued after the Laacher See volcanic eruption in Germany at ~12,900 cal yr. Deposition of the WM occurred episodically throughout the Lateglacial and terminated by the early Holocene. The time interval between the end of WM deposition and subsequent burial by flood basin peat reflects a duration of exposure of at least 3500 yrs. Since regional water table rise affected the area ~5000 cal yrs ago, the early Holocene water table must have been maintained by spring fed ground water sources from nearby ice pushed ridges.

Deposition of the WM is associated with transitional braided to meandering fluvial channels during times when the Rhine-Meuse Valley experienced a sensitive response to rapid climate change. The WM is regionally time transgressive and probably formed during flood plain transitions between permafrost and base-flow driven hydrologic regimes. Regional landscape dynamics suggest that WM deposition and subsequent preservation was driven by fluctuations of the southern limit of permafrost during Northern Hemisphere deglaciation.

In order to validate existing models of sedimentation in active sedimentary environments, detailed stratigraphic information is indispensable. Near-surface geophysical methods provide a means to acquire high-resolution images of the stratigraphic succession in the shallow subsurface. Land-based and marine methods have been tested in the Verdronken Land van Saeftinge. This intertidal flat area is cut by numerous tidal gullies, and high tidal amplitudes enable the application of different techniques at various water levels. Data acquisition focused on the upper 10 – 20 m of the active sediment bodies. Applied techniques include high-resolution seismic acquisition, geo-electrical methods (DC resistivity), electromagnetic techniques, CPT, and manual drilling. In general the acoustic methods allowed more reliable and detailed interpretation of the sedimentary structures than the electric/electromagnetic methods. The latter suffered from the effect of tidal action and salt-water intrusion, and their application on land proved very strenuous. CPT and shallow cores provided valuable ground-truth information. The results clearly indicate that no single technique can provide all the answers. Only an integrated use of (complementary) methods will allow getting a better grip on the sedimentary architecture and preservation potential in active estuarine sedimentary environments.

The River Rhine and its tributaries represent one of the largest drainage systems in Europe. Its prominence among other fluvial systems is due to the location of its headwaters within the central Swiss Alps, which were repeatedly glaciated during the Quaternary, and the concurrence of major parts of the River Rhine course with the European Cenozoic Rift System. Sediments of the Rhine have thus recorded both changes in climate and tectonic activity as well as sea level change in the lower part of the river course.

The River Rhine is composed of different subdivisions characterised by distinct geographical and geological settings. Vorder-and Hinterrhein in the headwaters are inner-alpine rivers frequently influenced in their course by tectonic lines and the blockage of valley floors by the deposits of mass movements. The Alpenrhein is located in a main Alpine valley that drains into a large foreland basin, the Bodensee (Lake Constance). The Hochrhein flows out of the lake following the Jura Mountains in a western direction. All these areas display a series of geological features such as moraine ridges and outwash plains, which directly reflect Quaternary glaciations of the Alps. The Oberrhein (Upper Rhine) Valley, as a graben structure, is part of the rifting system that started to develop during the middle Tertiary. The northern end of the graben is represented by the triple junction of the Mainz Basin, which is mainly characterised by the remains of marine transgressions that occurred during the initial rifting phase. The Rhine continues following the western branch of the tectonic system by passing through the Rhenish Massif. Uplift in this so-called Mittelrhein (Middle Rhine) area is well documented by a flight of late Tertiary to Quaternary river terraces. This region is also characterised by young volcanic activity as found, for example, in the Eifel volcanic field. The Niederheinische Bucht (Lower Rhine Embayment), especially the Roer Valley Rift System, represents the northern continuation of the rifting system. This area is characterised by differential uplift in the southern and subsidence in the northern part of the basin, which continues into the Netherlands. Here, the main stream of the River Rhine is separated into different branches developing an active delta at the coast of the North Sea. When the North Sea Basin was covered by ice during the Elsterian, Saalian and probably also the Weichselian glaciation and global sea level was low, the Rhine continued its course through the English Channel and flowed into the North Atlantic off Brittany.

The locality of Langenboom (eastern Noord-Brabant, the Netherlands), also known as Mill, is famous for its Neogene molluscs, shark teeth, teleost remains, birds and marine mammals. The stratigraphic context of the fossils, which have been collected from sand suppletions, was hitherto poorly understood. Here we report on a section which has been sampled by divers in the adjacent flooded sandpit ‘De Kuilen’ from which the Langenboom sands have been extracted. The studied section covers part of the marine Miocene Breda Formation and Pliocene Oosterhout Formation, and is topped by fluvial Quaternary deposits of presumably the Beegden Formation. The Breda Formation (15 – 18 m below lake surface) in this section is, based on organic walled dinoflagellate cysts, of an early-middle Tortonian age. The Oosterhout Formation (7 – 15 m below lake surface) comprises two depositional sequences, the lower of which (12 – 15 m below lake surface) presumably is the source of most Langenboom fossils. Combined dinoflagellate cyst and benthic mollusc indicators point to an early Zanclean - early Piacenzian age for this lower cycle. Its basal transgressive lag and (to lesser extent) top comprise reworked Tortonian taxa as well, Dinoflagellate cysts and a single benthic mollusc point to a Piacenzian age for the upper Oosterhout Formation sequence (7 – 12 m below lake surface).

The Paleocene-Eocene Thermal Maximum (PETM), ~55.5 Myr ago, was a geologically brief (~170 kyr) episode of globally elevated temperatures, which occurred superimposed on the long-term late Paleocene and early Eocene warming trend (Fig. 1). It was marked by a 5 – 8° C warming in both low and high-latitude regions, a perturbation of the hydrological cycle and major biotic response on land and in the oceans, including radiations, extinctions and migrations (see overviews in Bowen et al., 2006; Sluijs et al., 2007a).

Geochemical studies on Upper Carboniferous marine bands showed that marked enrichment in redox-sensitive trace elements (uranium (U), vanadium (V), molybdenum (Mo)) mostly occur if they contain Goniatites. Goniatites indicate deposition in relatively distal and deep marine environments. In contrast, Westphalian marine bands found in the Netherlands predominantly show a Lingula facies, indicating deposition in a nearshore environment. These Lingula marine bands are mostly lacking significant trace element enrichments. The aim of this paper is to explain the mechanisms causing the differences in geochemical characteristics between distal (Goniatites facies) and proximal (Lingula facies) marine bands. Geochemical analyses (total organic carbon (TOC), sulfur (S), major and trace elements) were carried out on a selection of these marine bands. Furthermore, a comparison was made with some lacustrine bands which broadly show the same sedimentary development as the Lingula marine bands. The results show that the Lingula marine bands, in contrast to the Goniatites and lacustrine bands, are characterised by low organic carbon contents (1 – 2 wt.%). A relatively high input of siliciclastics probably prevented the accumulation of organic-rich layers (dilution effect). In turn, low organic carbon contents most likely prevented the effective scavenging of trace elements. Although the lacustrine bands are characterised by high TOC contents, here the limited availability of trace elements in fresh water forms the best explanation for low trace metal enrichments. Since marine bands form stratigraphically important horizons in the Upper Carboniferous, many attempts have been made to recognise marine bands using well logs (gamma-ray). The results from this study show that using gamma-ray devices (detecting U-enrichments), only marine bands in a Goniatites facies are clearly recognised while Lingula marine bands are not detected.

The Gelderse IJssel is the third major distributary of the Rhine in the Netherlands and diverts on average ~15% of the Rhine discharge northward. Historic trading cities are located on the Gelderse IJssel and flourished in the late Middle Ages. Little is known about this river in the early Middle Ages and before, and there is considerable debate on the age and origin of the Gelderse IJssel as a Rhine distributary. A small river draining the surrounding Pleistocene uplands must have been present in the IJssel valley during most of the Holocene, but very diverse opinions exist as to when this local river became connected to the Rhine system (and thereby to a vast hinterland), and whether this was human induced or a natural process. We collected new AMS radiocarbon evidence on the timing of beginning overbank sedimentation along the lower reach of the Gelderse IJssel. Our data indicate onset of overbank sedimentation at about 950 AD in this reach. We attribute this environmental change to the establishment of a connection between the precursor of the IJssel and the Rhine system by avulsion. Analysis of previous conventional radiocarbon dates from the upper IJssel floodplain yields that this avulsion may have started ~600 AD. Our results contradict earlier suppositions, based on interpretation of archaeological data and historical accounts, that the Gelderse IJssel is much older and originated as a canal, dug under supervision of the Roman general Drusus.

Solar activity, as manifested by its many equatorial as well as high-latitude components of short-term variability is regulated by the Sun’s dynamo. This constitutes an intricate interplay between the solar toroidal and poloidal magnetic field components. The dynamo originates in the tachocline, which is a thin layer situated about 200,000 km beneath the solar surface. The dynamo is a non-linear system with deterministic chaotic elements, hence in principle unpredictable. Yet there are regularities in the past behaviour, such as the Grand Maxima (example: the recent high maximum of the 2nd half of the 20th century) the Grand Minima (e.g. the Maunder Minimum between 1650 and 1710) and the Regular Oscillations such as those between 1730 and 1923. Their occurrences are described by a phase diagram in which a specific point can be identified: the Transition Point. This diagram plays an essential role in determining the future solar activity. Guided by its quasi-regularities and by recent measurements of the solar magnetic fields we find that the Sun is presently undergoing a transition between the past Grand Maximum and a forthcoming period of Regular Oscillations. We forecast that this latter period will start in a few years and will continue for at least one Gleissberg cycle and that the next solar maximum (expected for 2014) will be low (Rmax ~ 68).

We discuss the heliospheric drivers of Sun-climate interaction and find that the low-latitude magnetic regions contribute most to tropospheric temperatures but that also the influence of the - so far always neglected - polar activity is significant. Subtraction of these components from the observed temperatures of the past 400 years shows a residual series of relative peaks and dips in the temperature. These tops and lows last for periods of the order of the Gleissberg cycle. One of these is the recent period of global warming, which, from this point of view, is not an exceptional period.

We describe the occurrence in the Netherlands of three teeth of Mimomys hajnackensis (Arvicolidae, Rodentia) from three separate boreholes extending into matine deposits of the Maassluis Formation. These marine Pliocene/Early Pleistocene deposits at depth are overlain by, and interdigitate eastwards with, the freshwater deposits of the Waalre and Peize Formations (formerly known in part as the Tegelen Formation). Teeth identified as M. hajnackensis have not previously been described from the Netherlands although similar material has been reported from Pliocene deposits in Germany at Frechen and Hambach close to the Dutch border. The material described here comes from boreholes at the Polder de Biesbosch near Dordrecht, Diepenveen and Deventer. To our knowledge, these finds represent the oldest described rodent fossils from the Netherlands, corresponding to an absolute age of 2.9 to 3.3 Ma on the basis of comparison with other European localities, implying that the remains are reworked from older deposits.

The Pliocene and Quaternary unconsolidated sediments of the Upper Rhine Graben (URG) were petrographically analysed in numerous high quality drill cores. The heavy mineral composition of the Graben sediments was compared to those from the Graben margins. In addition, the sedimentary lithofacies were investigated. The chronological classification of the sedimentary successions was established by the interpretation of sporadic palaeontological and palaeomagnetic data.

Within the Pliocene sediments, two distinguishable heavy mineral assemblages indicate different source areas of the Graben fill. At first, a heavy mineral assemblage of stable minerals (turmaline, zircon and anatase) indicates a contribution of debris supplied from Buntsandstein areas at the Graben margins. Secondly, a mixed association of stable minerals in combination with unstable (garnet, hornblende, less epidote) and distinct rare minerals (e.g. monazite, xenotime) can be traced back to debris derived from the crystalline rocks of the southern Graben margins (Black Forest, Vosges). The distribution of sediments with this mixed heavy mineral assemblage proves the fluvial sediment transport from south to north and therefore the course of the Pliocene proto-Rhine along the Graben.

The correlation between the Quaternary sediment successions in the south and the north of the Graben is problematic due to their variable thicknesses as well as their changing lithofacies.

In the southern URG, the Quaternary strata could be subdivided into the older Breisgau Formation and the younger Neuenburg Formation based on characteristic lithofacies. Within this succession, the lower part of the Breisgau Formation (lower Breisgau beds) can be distinguished by noticeable lower contents of hornblende, which probably reflects the effects of weathering and solution of these unstable minerals due to repeated discontinuities during the sediment accumulation. The sediments of the upper part of the Breisgau Formation (upper Breisgau beds) and of the Neuenburg Formation contain a heavy mineral assemblage of garnet, epidote and hornblende, which is typical for Rhine deposits with Alpine contribution. This probably unaffected composition indicates a more unvaried and rapid accumulation of predominantly Alpine debris. In the northern URG, the Quaternary strata are subdivided into three aquifers and intercalated fine-grained horizons. Here, the Quaternary sediments can be petrographically classified into Rhine deposits (garnet, epidote and hornblende) and local accumulations contributed from the Graben margins (turmaline, zircon and anatase) without contemporaneous influence of the Rhine. The analytical results obtained from several drill cores in the northern URG provide evidence for the spatial and temporal variability of the course of the Rhine during the Quaternary.

Biostratigraphical re-analysis of palaeobotanical data from the De Lutte-06 well clarifies an earlier controversy regarding the stratigraphical interpretation of this well based on palaeobotanical and palynological analysis. Previous biostratigraphical studies suggested an early Westphalian D age for the major part of the De Lutte formation, with only at the topmost part of the well remnants of presumable but unconfirmed Stephanian deposits. New identifications of palaeobotanical samples illustrate the presence of plant macrofossil assemblages in the De Lutte Formation characteristic for the latest Westphalian D to the Stephanian B-C. These new palaeobotanical insights, therefore, confirm a younger age for the De Lutte Formation and are more in line with the earlier palynological observations from the De Lutte-06 well that suggested that the recovered palynofloras resembled typical Stephanian associations.

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

Recent carried out core drillings in the Ludwigshafen/Speyer area permit an improved stratigrahical differentiation of the Plio-Pleistocene deposits in the northern Upper Rhine Graben. Lithofacies analysis, pollen analysis, heavy mineral analysis, and palaeomagnetical results, lead to a subdivision of ‘Kieslager’ (gravel-layers) and ‘Zwischenhorizonte’ (interlayers). In the scope of geological mapping near Mannheim and Speyer, the genesis and the stratigraphic position of Middle and Late Pleistocene fluvial terraces was re-assessed (‘Frankenthaler Terrasse’). The terrace has a complex composition, marking two phases of accretion followed by abandonment: a first phase took place in (Elsterian? to) Saalian times, the second phase during the Weichselian. Tectonism further complicates the sequence, in particular in the area between Ludwigshafen and Speyer, which is the SW rim of the ‘Heidelberger Loch’-structure. In this area ‘terraces’ occur they are the result of faulting rather than fluvial dissection alone.

Determining sea-level change caused by continental ice mass variations is a far more complicated matter than one might think. Even if effects like induced changes in ocean currents or thermal expansion of ocean water are neglected, melt water does not redistribute uniformly and homogeneously over the world’s oceans. If land ice melts, the gravity field of the earth changes due to the redistribution of the ice and melt water masses.