We report the discovery of a new species of marine reptile, a mosasaur, from the Upper Cretaceous (Maastrichtian) of The Netherlands. Prognathodon saturator sp. nov. is represented by an almost complete skull and much of the postcranial skeleton, and is one of the largest mosasaurs discovered to date. The stout skull and extremely massive jaws are more powerfully built than in any other known mosasaur. Bite marks, the partial disarticulation and scattering of the skeleton, and the presence of associated teeth of Squalicorax and Plicatoscyllium suggest extensive scavenging by sharks.

The collection of extended and updated abstracts presented here resulted from a two-day workshop of the Collaborative Research Centre ‘Interactions between and Modelling of Continental Geo-Systems’ (SFB 350) held on 19th and 20th November, 1999 at the Rheinische Friedrich-Wilhelms-Universität Bonn. This workshop was entitled ‘Rift Tectonics and Syngenetic Sedimentation - the Cenozoic Lower Rhine Graben and Related Structures’. Its central topic was devoted to various approaches of understanding the evolution of a young graben structure, with the aim to trace the interaction of tectonics, sedimentation, facies development, burial history, and coherent structural behaviour by integration of geodetic, seismological, gravimetric, sedimentological, paleontological, and climatological data.

Fluvial 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.

Since 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.

The Pleistocene College Farm Silty Clay Member of the Creeting Formation at Great Blakenham, Suffolk, south-east England is shown to contain indigenous and recycled dinoflagellate cysts and other derived palynomorphs. The indigenous dinoflagellate cysts indicate a marine influence during deposition of the clay, whilst the other palynomorphs demonstrate derivation of sediment from a wide catchment of Carboniferous, Jurassic and Cretaceous bedrocks. It is argued, by comparison with palynological data from the Chillesford Clay Member of the Norwich Crag Formation some 25km to the east, that these sediments were eroded from western, south-central and south-eastern Britain, and transported by the early River Thames to its estuary, where they were redeposited at the western margin of the Crag Basin, during the Early Pleistocene Tiglian TC3 Substage. This interpretation refines earlier research which concluded the College Farm Silty Clay was deposited in a predominantly freshwater environment, such as a lagoon, without any direct access to the sea or major river.

The deep subsurface temperature data of the Roer Valley Graben have been re-analysed and combined with new temperature data from hydrocarbon exploration wells. The results show that the deep subsurface temperature distribution in the Roer Valley Graben is essentially the same as in the relatively stable high bordering the Roer Valley Graben to the southwest. Thus, the Cenozoic tectonic evolution of the Roer Valley Graben, which is characterized by uplift and denudation during the Late Eocene and subsidence due to rifting starting from Late Oligocene, has hardly affected the temperatures in the graben, which is probably due to the slow subsidence and sedimentation rates. In contrast to what is suggested on previously published temperature maps, the Roer Valley Graben is probably not a relatively cold area in the Netherlands.

Within 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.

Effects of flow in the lower continental crust have often been ignored in the geomorphological literature on the growth of topography during the Quaternary. However, the ability of the lower crust to flow in response to horizontal pressure gradients, caused by lateral variations in the depth of the base of the brittle upper crust, results in two mechanisms for the growth of topography, which can occur either separately or in combination. First, an increase in the rate of erosion in a region will result in a progressive reduction in the depth of the base of the brittle layer, which will drive inflow of lower crust to beneath the region, which will increase the crustal thickness and thus the altitude of the Earth’s surface. It is important to note that this mechanism can increase the mean altitude of the Earth’s surface, not just the altitude of summits formed of erosion-resistant rock or other features that are not eroding, which will rise faster than the surrounding eroding landscape. Second, repeated cyclic surface loading by ice sheets or fluctuations in global sea-level will cause net flow from areas of relatively cool lower crust to beneath areas of warmer crust. This process will thus usually result in net flow of lower crust from beneath offshore areas to beneath land areas, thinning the crust and increasing the bathymetry offshore but adding to the crustal thickness and so uplifting the land surface onshore. Although these two processes have different mechanisms, the time scale over which both operate is governed by the time required for heat diffusion, resulting from lower-crustal flow (which is concentrated near the Moho), to affect the position of the base of the brittle layer. As a result, the uplift responses for both processes can be very similar. This means that to resolve the physical cause of uplift at any locality requires knowledge of the regional conditions before uplift began, not just evidence (such as river terrace sequences) from during the course of uplift. This study illustrates the complexities and practical difficulties that can result from these issues, using case studies of localities that have been modelled in detail. It also points out that, although the ability to carry out quantitative calculations involving lower-crustal flow is new, the idea that such flow provides a general mechanism for the growdi of topography was first suggested in the early 19th century, but was later abandoned - apparently mistakenly. An early Middle Pleistocene increase in uplift rates is widely-recognised from river terrace records, and typically marks a transition from broad valleys in areas of low relief to narrower, more deeply incised gorges. It is suggested that the isostatic response to cyclic surface loading, caused by the growth and decay of continental ice sheets and the associated sea-level fluctuations, is the main cause of this change, following the increase in scale of ice sheet development from oxygen isotope stage 22 (~0.9 Ma) onwards. The less well resolved earlier increase in uplift rates, evident in some river terrace records at ~3 Ma, is more likely to result from the isostatic response to increased rates of erosion linked to the contemporaneous deterioration in climate.

The 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.

Long-term river terrace sequences reveal that many regions have uplifted by several hundred metres since the Middle Pliocene. They indeed provide evidence of a global increase in uplift rates in die Late Pliocene, followed by a calm period then a renewed increase around the Early-Middle Pleistocene boundary. It is suggested that this uplift pattern has resulted from thickening of the continental crust caused by flow in the lower crust which has been induced by cyclic surface loading caused by growth and decay of ice sheets and the associated global sea-level fluctuations. Observed uplift histories are modelled using a technique which incorporates increases in the strength of forcing of this process caused by step changes in the intensity of glaciations starting at~3.1,~2.5,~1.2, and~0.9 Ma.

Ground-penetrating radar data from a regular grid are used to study the internal structure and development of a 9-m high aeolian river dune in the Dutch Rhine-Meuse delta. The purpose of this investigation was to image the internal sedimentary structures to better understand the development of these aeolian river dunes. Three radar facies can be recognised in the GPR sections. Radar facies 1 has a maximum thickness of 5 to 6 m and is characterised by dipping, parallel reflections with a maximum length of at least 20 m. The reflections from perpendicular sections, analysed using closed-loop correlation in 3-D-interpretation software, form eastward dipping (14° maximum) surfaces. Radar facies 2 is one continuous, sub-horizontal reflection. This high amplitude reflection is most probably caused by a thin organic horizon. Radar facies 3 has a thickness of 3 to 4 m and is made up of sets of short, predominantly eastward to north-eastward dipping reflections separated by rather continuous, sub-horizontal reflections. The eastward dipping surfaces in radar facies 1 are foresets of a dune that was deposited by prevailing westerly winds in the Younger Dryas, the last cold period in the Pleistocene. During the Early Holocene, an increasing vegetation cover stabilised the dune and formed a thin organic horizon. Subsequent resumption of dune forming processes led to the formation of radar facies 3 on top of the vegetated Pleistocene dune. Sedimentation by small dunes, partly eroding each other, led to sets of cross-stratification separated by bounding surfaces. The results suggest a small change in palaeo wind direction.

This 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.

The Pleistocene development of the lower Severn valley is recorded in the fluvial sediments of the Mathon and Severn Valley Formations and their relationship to the glacigenic Wolston (Oxygen Isotope Stage 12), Ridgacre (OIS 6) and Stockport (OIS 2) Formations. The most complete stratigraphical record is that of the Severn Valley Formation, which post-dates the Anglian Wolston Formation and comprises a flight of river terraces, the highest of which is c.50 m above the present river. The terrace staircase indicates that the Severn has progressively incised its valley during the post-Anglian period. The terrace sediments are predominantly composed of fluvially deposited sands and gravels, largely the result of deposition in high-energy rivers under cold-climate conditions. Occasionally towards the base of these terrace deposits low-energy fluvial facies are preserved which contain faunal remains and yield geochronology which support their correlation with interglacial conditions. This simple stratigraphy supports a climate-driven model for the timing of terrace aggradation and incision, with the incision mode at its most effective during the cold-warm transitions and the aggradational mode at its most effective during warm-cold climate transitions. The chronology of terrace aggradation in the lower Severn seems to correspond with the Milankovitch lOOka climate cycles. The timing of incision events suggests that base level (eustatic sea-level) changes do not play a significant role i.e. incision occurs as sea-level is rising.

Although climate change is significant in governing the timing of incision, the long-term incision of the River Severn appears to be driven by crustal uplift. A long-term incision rate of 0.15 m ka1, calculated using the base of the terrace deposits, is believed to closely equate with the long-term uplift rate. Superimposed on this long-term uplift are periods of complex terrace sequence development resulting from rapid incision during periods of glacio-isostatic rebound, with large incision events reflecting the rebound adjustment to late glacial stage isostatic depression. However, in no case in the Severn valley has glacial encroachment led to enhanced incision, suggesting that there has been no additional uplift resulting from isostatic compensation for glacial erosion.

On the basis of a multidisciplinary approach we have unraveled the palaeo-earthquake history of a trenched section across the Peel Boundary Fault. The area shows at present one of the largest contrasts in relative motion on both sides of the fault on the basis of repeated levelling. The geological record for the last 25 thousand years, recovered in the trench, shows evidence of two heavy earthquakes (moment magnitude between 6.0 and 6.6), that occurred in a relatively short timespan around 15 thousands years ago. A third less severe event occurred somewhere in the mid Holocene. The time interval between the two large events is in the order of 1500 years, an interval comparable to that between the last volcanic explosions in the nearby Eifel area. Both records together seem to suggest a relation between large-scale faulting and volcanic activity in the nearby Eifel area, but this interpretation is based on one trench only and should be tested by opening more trenches in the zone that is assumed to be affected by these large events.

Based 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.

Information about the morphology and alluvial sediments of the Dnieper Valley is reviewed. The Dnieper Valley originated in the Late Miocene. The Middle Dnieper Valley is an intercontinental alluvial basin and the Lower Dnieper Valley is a shallow canyon that ends with a delta. Identification of the alluvial dynamic facies (channel, overbank, abandoned channel) is crucial for stratigraphical analysis. The dynamic facies form regular sequences - alluvial suites that combine into series. Individual suites and series are characterized by their mode of occurrence, facies composition, lithological features and expression in the modern landscape. Their stratigraphie position is established with reference to index beds and palaeontological, geochrono-logical and archaeological research, allowing them to be correlated along the valley. Correlation between different parts of the Dnieper system uses a combination of facies and geomorphological analyses, whereas correlation with other river systems makes use of mammalian and molluscan biostratigraphy. Global events (marine regressions and glaciations) that brought about similar reactions in different fluvial systems can be also used for correlation.

The coversands along the Peel Boundary Fault in the Netherlands were investigated by a luminescence dating approach combining Infrared Optically Stimulated Luminescence (IRSL) and Thermoluminescence (TL) methods. At the Neer trench, ten samples were collected and investigated in order to set up an independent chronological framework for the deposition history of the fluvio-aeolian and aeolian sediments and hence the timing of Late Weichselian and Holocene earthquake events. Five sedimentary units could be distinguished by this chronological approach. The oldest fluvio-aeolian unit yielded a mean deposition age of 35.9±0.4 ka and is designated to correlate with the Middle Weichselian. An IRSL age estimate of 20.1 ±2.9 ka was determined for the sediment that most likely represents the Older Coversands I, and a mean luminescence age of 15.1±1.2 ka for deposits just below the Beuningen gravel bed. The aeolian sediment from above the Beuningen horizon yielded an IRSL age estimate of 9.4±1.0 ka. The youngest deposits from the colluvial wedge yielded <6.9±0.7 ka BP, and so an earthquake event was likely to occur during the Middle or Late Holocene, as evidenced by the luminescence age estimates.

More 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.

In 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.