climatic fluctuations reflected in the evolution of fluvial systems of central eastern europe 60 8 ka cal bp abstract in general the evolution of fluvial systems in central eastern europe reflects the main phases of climatic changes during the period of 60 8 ka cal bp registered in greenland ice cores and their isotopic 18 o curves the greenland isotope curve shows many more wiggles and stages than the fluvial record of the same time especially during the interpleniglacial phase in central eastern europe we observe several deviations from those climatic trends connected with different factors among which are the long distance of the region from the atlantic ocean and an increase in continentality at times this region was occupied by permafrost although the coexisting warm summers during a part of the studied period enabled the presence of a forest cover these factors together controlled the specific features of the fluvial regime and sediment load reflected in alternating trends to erosion or aggradation and from meandering to braiding the permafrost influenced snowmelt floods and tendency to braiding the dense vegetation with trees reduced the supply of sediments and stabilized the meandering channels very distinct changes occurred in the river valleys that drain the mountains where ceaseless fluctuations of vegetation vertical zones were present especially during the unstable interpleniglacial when the supply of load from the higher vegetation zones was increased this system controlled by the climate and plant vegetation was modified by other factors including tectonics wind activity during dry periods blocking of valleys by ice sheets meltwater supply and sea level fluctuations of two reservoirs

formation and persistence of mollisols on zeolitic deccan basalt of humid tropical india in contrast to generally observed non acidic and less weathered mollisols in temperate semi arid and humid climate acidic and fairly weathered mollisols on deccan basalt are observed in hills of central satpura range madhya pradesh and western india western ghats maharashtra under forest in the present tropical humid climatic conditions the detailed morphological chemical and mineralogical investigations of these mollisols of central and western india indicates that due to the presence of zeolites in the deccan basalt the transformation of smectite to kaolinite was prevented and the retention of adequate amount of smectite and continuous supply of calcium ions from zeolites made the formation of mollisols in forest even under tropical humid climate the formation and the persistence of these mollisols in association with acidic alfisols under sparse forest in the basaltic landscape of millions of years in central and western india demonstrates the primary importance of the quality of parent material rich in expanding clay mineral and bases in their formation this unique example thus expands the basic knowledge on the formation of mollisols in the humid tropical part of the world

the cenozoic evolution of the roer valley rift system integrated at a european scale the roer valley rift system rvrs is located between the west european rift and the north sea rift system during the cenozoic the rvrs was characterized by several periods of subsidence and inversion which are linked to the evolution of the adjacent rift systems combination of subsidence analysis and results from the analysis of thickness distributions and fault systems allows the determination of the cenozoic evolution and quantification of the subsidence during the early paleocene the rvrs was inverted laramide phase the backstripping method shows that the rvrs was subsequently mainly affected by two periods of subsidence during the late paleocene and the oligocene quaternary time intervals separated by an inversion phase during the late eocene during the oligocene and miocene periods the thickness of the sediments and the distribution of the active faults reveal a radical rotation of the direction of extension by about 70 80j counter clockwise integration of these results at a european scale indicates that the late paleocene subsidence was related to the evolution of the north sea basins whereas the oligocene quaternary subsidence is connected to the west european rift evolution the distribution of the inverted provinces also shows that the early paleocene inversion laramide phase has affected the whole european crust whereas the late eocene inversion was restricted to the southern north sea basins and the channel area finally comparison of these deformations in the european crust with the evolution of the alpine chain suggests that the formation of the alps has controlled the evolution of the european crust since the beginning of the cenozoic

long term fluvial archives in hungary response of the danube and tisza rivers to tectonic movements and climatic changes during the quaternary a review and new synthesis abstract the paper discusses the quaternary evolution of the danube and tisza rivers and their main tributaries in the context of evolution of the entire pannonian basin which is europe s largest intramontane basin within the alp carpathian orogen the palaeo drainage reconstruction of the pannonian basin for the pre quaternary period is outlined in connection with the gradual regression of lake pannon since the late miocene deltas of rivers that entered the basin from the northwest and northeast were gradually transformed into extended alluvial plains thus the earliest possible ancestor of the danube coming southeastwards from the alps could be as old as late miocene by the pliocene the whole lake pannon was infilled the former extensional basin formation was replaced by a compresional stress field which resulted in an uplift of the marginal flanks and late stage subsidence anomalies the increasing relief led to the formation of the quaternary drainage pattern the actively subsiding young basins were filled by fluvial sediments transported by the danube and tisza river systems from the uplifting mountains between the subsiding regions of the little and great plains the danube has formed an antecedent valley with terrace staircases between the uplifting sections of the transdanubian range and the north midmountains the formation of the terraces is attributed to periodic climate changes during the pleistocene combined with differences in the uplift rate the paper gives a complex overview of the classical chronology of the six terraces based on various data sources mostly dating of loess paleosol sequences travertines aeolian sand and tephra strata overlying the fluvial sediments complemented by scattered vertebrate faunal data and archaeological evidence directly from the terrace sediments the quaternary drainage pattern evolution of the great plain with a strong tectonic control is discussed in detail rivers originating from the uplifting marginal areas were drawn towards the subsiding depressions which served as local base level changes in subsidence rates in space and time throughout the quaternary resulted in the evolution of a complex drainage pattern a special emphasis is placed on the late pleistocene holocene development of the middle tisza region and the koros basin where the berettyo koros rivers form an eastern tributary system of the tisza river a comparative evaluation of these two areas is especially relevant as they provide insights into large scale late pleistocene avulsion of the tisza river osl dating complemented with inferred transport directions determined from heavy mineral analysis of fluvial sediments in the koros basin has revealed an ancient large meandering river system that can be identified with the palaeo tisza which was flowing along a tectonically controlled depression during the late pleniglacial successions in the middle tisza region have allowed differentiation between the older channels of the palaeo bodrog river and the sajo hernad alluvial fan and the younger meander belts of the new course of the tisza in the tisza system changes in river style braided to various scales of meandering show correspondence to millennial scale climate changes of the last 25 ka while in the koros basin the effects of tectonics are overprinted onto the regional climatic signals

spatio temporally variable response of fluvial systems to late pleistocene climate change a case study from central germany abstract the change of the earth s climate and anthropogenic forcing challenge catchment management as the deliberate use of the fluvial system s natural resources depends to some extent on the predictability of the system s variable sensitivity to external impacts the alluvial history of the wetter valley in central germany provides an example of the occurrence of a spatio temporally variable catchment sensitivity to the late pleistocene climate change empirical models that are based on sediment flux controls such as sediment supply transport capacity and gradient serve to explain differential floodplain construction during the early younger dryas the large scale basin upland morphology caused localised divergent cooling impacts and vegetation changes which generated reach scale variable sediment transport system states in the wetter valley the spatial arrangement of reach scale variable response is ascribed to the tectonically driven morphological configuration of the wetter catchment the crucial amplification of differential floodplain construction can be assigned to the spatially variable availability of a surplus of laacher see tephra particles in manner of a pulsed sediment input the ubiquitous tephra cover was previously deposited by the laacher see volcano event in the upper allerod thus the reach scale variable response during the early younger dryas can be deemed to have been climatically triggered but superimposed by an internally driven specific upstream catchment response the documented processes of late quaternary alluviation in the wetter valley imply the need for whole catchment approaches the latter are a prerequisite to reveal the occurrence and causalities of variable fluvial response in relation to external impacts that interact with internal morphological controls this is seen to be crucial to achieve an improved predictability of future environmental change in fluvial landscapes

late quaternary evolution of the feldbiss fault roer valley rift system the netherlands based on trenching and its potential relation to glacial unloading abstract the most important tectonic structure in the southern part of the netherlands is the roer valley rift system rvrs the main border fault zones of the rvrs the peel boundary and the feldbiss fault zones have been active during the quaternary and are still active today as indicated by the occurrence of earthquakes in this paper we present the results of a trench across the feldbiss fault part of the feldbiss fault zone this trench provided no evidence for earthquakes along this segment of the fault zone fluidization structures were not encountered a sudden increase in the average fault displacement rate was inferred for the period around 15 ka b p in a trench nearby across the geleen fault of the same fault zone the limited age control cannot exclude that such an acceleration also occurred at the feldbiss fault during the second half of the 1990 s several paleoseismological trenching studies have been carried out in the rvrs the compilation of the results of these studies reveals that the main border faults possibly experienced an increase in fault activity around 10 15 ka b p the timing of this increased activity and results from glacial rebound modelling indicate that glacial unloading of the crust can have triggered this increase in fault activity

interplay between climatic tectonic and anthropogenic forcing in the lower rhine graben the roer river the roer is a small river which drains the rhenish shield and confluences with the meuse river up to now the geological climatological biostratigraphical and pedological setting of the roer valley were not sufficiently integrated to disentangle the effects of external forcing factors on the roer river in this study we perform a detailed and integrated reconstruction of the fluvial morphology and palaeogeography of the roer river in order to determine responses to combined climatic tectonic and anthropogenic forcing factors the roer river has formed five terrace levels since the weichselian late pleniglacial fluvial planform of the roer river was predominantly climate controlled during the lateglacial and early holocene reach to reach variations in river terrace formation and fluvial planform change occur due to variations in tectonic setting subsurface geology base level fluctuations and the confluence with tributary systems differential subsidence by active faulting in the roer valley graben during the early lateglacial caused a preferential usage of the down tilt channels of the up to then double channel belt systems in the roer valley this preferred channel avulsion towards a fault zone leaving an underfit system on the up tilted side and the clustering of holocene roer channels along that fault zone meet the criteria for a lateral response of the roer river to a tectonic forcing anthropogenic influences in the form of deforestation and land use changes during the late holocene are responsible for the formation of a final terrace level and overbank sediments 2019 elsevier b v

neotectonics of the netherlands a review abstract earthquakes and vertical land movements inferred from geodetic levelling results demonstrate that the netherlands is situated on a tectonically active part of the earth s surface tectonic subsidence analyses of the sedimentary records in the basins and the history of tectonic uplift inferred from meuse river terraces show that the current tectonic activity is part of a deformation phase which began in the late early miocene which we take as the start of the neotectonic period the neotectonic faulting mode is normal slip this is in accordance with the present day orientation of the maximum horizontal stress and the vertical orientation of the maximum stress however the neotectonic fault zones are reactivated variscan or older wrench faults these faults have been reactivated repeatedly during the mesozoic and cenozoic in normal and wrenching modes and therefore represent fundamental crustal weakness zones as a result the surficial neotectonic fault pattern resembles the inherited wrenching fault pattern although the faulting mode is normal slip this is illustrated for the area where normal faults have displaced the meuse fluvial terrace system in the southeastern part of the netherlands the neotectonic vertical motions in and around the roer valley rift system have affected the courses of the rhine and meuse rivers from pliocene times until the present in addition a fluvial terrace staircase developed along the meuse river in response to the uplift of the ardennes rhenish massif and its foreland for example near maastricht furthermore small fault scarps are present along segments of the bounding fault zones of the roer valley graben the peel boundary fault zone and the feldbiss fault zone in other parts of the netherlands the neotectonic vertical motions have no direct expression in the morphology examples of possible indirect control on the morphology in these areas occur in glacial landscapes the zuiderzee basin and the coastal zone

buried dark soil horizons and archaeological features in the neolithic settlement region of the lower rhine area nw germany formation geochemistry and chronostratigraphy abstract the properties and age of buried humic and clay rich dark soil remains bht horizons and pits at archaeological excavations in the lower rhine basin nw germany were investigated these bht features were formerly described as a component of luvic phaeozems and as relics of chernozemic soils field observations challenge this interpretation the bht horizons in the lower rhine basin occur in a patchy distribution independent of relief position and climatic condition and they are mostly connected with artefact free but human made pits off site features consisting of the same bht material the presence of charred organic matter pyrogenic carbon and its radiocarbon ages suggested that these bht horizons are not relics of naturally formed soils but rather archaeological features pyrogenic carbon produced during agricultural burning practices e g slash and burn in the younger to end neolithic 4400 2200 bc led to the characteristic dark colouring of the soil material previously it was generally presumed that the parent material of those dark soils is pleistocene loess new irsl and osl ages around 6 4 4 3 ka indicate that the bht horizons in the lower rhine basin formed in colluvial sediments which also date to the younger to end neolithic thus the history of human induced soil erosion in the lower rhine area started more than 1000 years earlier than assumed before it was most likely connected to neolithic burning practices slash and burn which subsequently triggered soil erosion and then influenced the formation of dark anthrosols by eluviation and illuviation of the partly charred dark humic material these anthrosols are an example of strong human impact on soil forming processes since the onset of agriculture

the relation between climate and river processes landforms and deposits during the quaternary abstract the extent to which river processes and morphology are dependent on climate is an old question when looking at large time scales climatic cyclicity seems to coincide with alternating events in fluvial development however the shorter the time scales at which fluvial development is considered the more it is difficult to find a close correspondence with climate evolution ultimately it appears that the response time of river processes to climatic change may restrict the sensitivity of the fluvial systems to adapt to short climatic oscillations the impact of climate on fluvial systems is largely transferred to these systems by the climate determined soil cohesion and peak discharges the latter factors are especially related to vegetation cover and permafrost conditions finally a number of basin characteristics are discussed that demonstrate that fluvial systems are not completely controlled by climate

investigation of the clay minerals composition of soils derived from basalt parent materials in the early miocene to early pleistocene on the arabian shield using multiple techniques implications for paleoclimatic conditions knowledge of clay minerals composition can be used to understand paleoenvironmental and or paleoclimatic conditions particularly for soils derived from volcanic parent materials that were subjected to diverse climatic conditions during pedogenesis in this study the clay minerals composition in soils developed from basaltic parent materials during the cenozoic mostly during the early miocene to early pleistocene in the harrats region of the arabian shield in saudi arabia were investigated forty seven clay samples were examined using selective dissolution analyses x ray diffraction xrd thermogravimetric analysis tg fourier transform infrared spectroscopy atr ft ir scanning electron microscopy sem and transmission electron microscopy tem to obtain a better understanding of the clay minerals developed in basaltic parent materials particularly under a dry hot environment the xrd results revealed that the clay mineralogy was dominated by smectite kaolin kaolinite halloysite and interstratified vermiculite chlorite vm ch with mica pseudo chlorite palygorskite and ca zeolites as minor components the tem provided strong evidence for the presence of allophane and imogolite which is in line with numerous previous studies on soils formed from basaltic parent materials the existence of poorly crystalline minerals in these soils was strongly supported by the selective dissolution analysis results the combined influence of paleoclimates and parent material is evidenced in the clay minerals in the studied soils the formation of smectite vm ch and chlorite minerals in the harrats soils could be attributed to the simultaneous effect of temperate paleoclimates that dominated the pliocene and the wet transition periods that occurred through the pleistocene into the mid holocene while the minor palygorskite and ca zeolites could be related to the dry conditions that started in the late holocene and persist to the present day additional studies regarding the clay mineral assemblages in similar geoenvironmental settings are highly recommend and should account for paleoclimatic conditions to provide a better understanding of the relationship between clay minerals and paleoclimates

the cenozoic lower rhine basin rifting sedimentation and cyclic stratigraphy in the cenozoic the lower rhine basin formed as a rift at the southeastern terminus of the dutch german central graben while the rhenish massif was uplifted the study focusses on the marginal marine and fluvial fill of the lower rhine basin a basin model is developed support for this study was given by extensive industry outcrop and well data by new stratigraphical and sedimentological observations the ingression and subsequent regression of the cenozoic north sea is analysed using the concept of base level cyclicity as the geohistory of the basin was complex a subsidence curve is constructed furthermore an attempt is made to trace the simultaneous uplift of the rhenish massif

climate forcing of fluvial system development an evolution of ideas starting from traditional ideas on the climatic steering of fluvial system dynamics it appears that there are different kinds of climatic influences on system dynamics they vary from direct climatic forcing like peak precipitation to indirect like permafrost and partial forcing like vegetation vegetation or its absence and not directly climate is considered as the main cause of fluvial incision or deposition during temperate or cold periods however other external factors than climate and non climatic factors such as local basin characteristics like subsoil lithology and relief express their effects on the fluvial systems by their role in the energy balance of the river catchment finally internal factors in fluvial system evolution like thresholds and response time should not be neglected

the pliocene and quaternary fluvial archives of the rhine system abstract the river rhine is one of the few major fluvial systems that connect the areas of the alpine glaciers and scandinavian ice sheet and so provides a key for correlating the two glacial areas in northern and middle europe the fluvial sequences of the rhine valley include at least 11 pleistocene terraces in the lower rhine area 2 pliocene and 12 pleistocene terraces in the middle rhine area resulting in 15 different pliocene and pleistocene terraces based on the correlation between lower and middle rhine the formation of fluvial terraces is significantly influenced by climatic and tectonic processes the terrace staircases are a result of uplift in the middle rhine area and the southern part of the lower rhine area whereas subsidence in the northern part of the lower rhine area resulted in buried stacked sequences magnetostratigraphic data provide chronological constraints for the terrace deposits in the lower rhine embayment and middle rhine region the matuyama brunhes boundary is a reliable marker horizon for the upper terrace fluvial deposits exposed in the karlich clay pit in the middle rhine area the first appearance of volcanic heavy mineral grains in the terrace sediments in loess and soils can be correlated from the middle rhine area through the lower rhine embayment to the netherlands the first occurrence of nordic components in terrace sediments of the lower rhine area is known from gravel on top of the kempen krefeld beds and so are younger than the holsteinian but older than the penultimate glaciation in the lower middle rhine area 40ar 39ar dating of tephra layers intercalated in the aeolian and fluvial sediments provide age constraints the upper pleistocene aeolian sediments overlying the terrace deposits have been dated by luminescence methods and the tephra from the laacher see eruption 12 860 bp is present in the younger lower terrace deposits

climate related river activity at the weichselian holocene transition a comparative study of the warta and maas rivers huvial systems from the dutch and polish lowlands are compared for their evolution during the weichselian deglaciation period in both regions the pleniglacial braided river pattern changed to a meandering pattern in the beginning of the lateglacial several transitional stages between braided and high sinuosity meandering systems have been recognized a difference in fluvial activity is found during the younger dryas when the maas transformed to a braided pattern while the warta maintained its meandering pattern phases of erosion and aggradation are more or less synchronous in the different river basins but their intensity may differ greatly the major characteristics of the fluvial systems are obviously a response to the general climatic evolution and related to changes in vegetation the regional differences are of minor importance and can be explained by site specific factors threshold values within the latter factors define the changes in river dynamics

sensitivity of west and central european river systems to environmental changes during the holocene a review abstract sediment deposition in floodplains is an essential part of the sediment dynamics of a catchment these sediment dynamics can vary largely on a holocene time scale under the influence of driving forces such as land use and climatic variations in this paper we review the holocene floodplain sediment deposition history of rivers in west and central europe with special attention to the influence of climate and land use variability during the early holocene preboreal to atlantic period most floodplains were rather stable with limited floodplain aggradation after this initial phase of relative stability sedimentation rates increase during the middle and late holocene with often the most important deposition phase during the last 1000 to 2000 a the start of the increase in sedimentation varies spatially with an earlier start in the west france germany then in the east poland belarus ukraine while there are also local differences between regions which are settled early e g loess regions compared to later settled regions the sedimentation history of most floodplains can be linked to the local land use history while influence of climatic variations on floodplain aggradation is often reported to be of minor importance processes related to bedload are often reported to be more influenced by climatic events relationships between the driving forces and the sediment history are mainly based on synchronicity and there is seldom proof for a direct causal relationship future research should focus on a system based approach integrating the floodplain deposition in the entire sediment dynamics which includes also erosion colluvial deposition and export main research questions that need further attention include integration of system based concepts like landscape connectivity and buffering effects and also the assessment of the individual contribution of land use changes and climatologic variations on the sediment dynamics detailed sediment budget studies combined with modeling studies can make an important contribution to the understanding of floodplain sediment dynamics

late pleistocene evolution of the rhine meuse system in the southern north sea basin imprints of climate change sea level oscillation and glacio isostacy high resolution continuous core material geophysical measurements and hundreds of archived core descriptions enabled to identify 13 late pleistocene rhine meuse sedimentary units in the infill of the southern part of the north sea basin the netherlands northwestern europe this sediment record and a large set of optical stimulated luminescence dates 14c dates and biostratigraphical data allowed to establish detailed relationships between climate change sea level oscillation glaciation history and the sedimentary development of the rhine fluvial system during the last glacial cycle marine isotope stages 5e 2 eemian weichselian a well preserved eemian sediment record was encountered as the infill of a late saalian mis6 subglacial basin part of this record reflects groundwater rise controlled fine grained sedimentation as a result of postglacial early eemian sea level rise it shows strong analogy to developments known from the holocene rhine meuse delta outside of the glacial depressions near coastal deposits are only fragmentarily preserved the early glacial rhine sediment record is dominated by organic debris and peat layers marking landscape stability and low fluvial activity part of this record may have been formed under near coastal conditions significant amounts of reworked marine biomarkers in the lag deposits of early pleniglacial mis4 fluvial systems indicate that this period is characterized by extensive reworking of older mis5 near coastal sediments despite the marked early pleniglacial climatic cooling input of new sediment from the drainage basin was relatively low a feature that is related to the presence of regolith protective relic soil complexes in the basin during the early middle pleniglacial a major rhine avulsion indicates the system was in an aggrading mode and that sediment supply into the lower reaches of the rhine had strongly increased this increase in sediment supply coincided with the timing of major climate cooling that occurred from 50 to 45 ka onwards the increase in sediment supply is related to final breakup of the soil complexes in the drainage basin after 24 ka a strong input of coarse grained gravelly sediments was observed which indicates a strong increase in physical weathering processes and periglacial controlled supply of bedload sediment in the catchment a time delay between climate change 30 ka and channel belt aggradation 24 ka is explained as a result of transport path length between source and sink and or effects of higher continental runoff rates after 22 ka the late middle pleniglacial late pleniglacial and lateglacial rhine meuse record testifies for strong influence of glacio isostatic controlled differential upwarping of the study area glacio isostatic controlled forebulge upwarping and lateral valley tilting is shown to have deflected rhine meuse channel belts after 35 ka glacio isostatic upwarping is seen as the main cause for strong incision during the first phase of the late pleniglacial 30 24 ka at later stage glacio isostatic controlled incision was overruled due to high climate controlled sediment input from the catchment and probably initial glacio isostatic subsidence migration of channel belts towards the direction of the former centre of glacio isostatic uplift indicates that glacio isostacy influenced rhine meuse paleogeography until far into the lateglacial 2007 elsevier ltd all rights reserved

the origin and tectonic significance of asymmetrical meander belts in the hebgen lake area of sw montana the madison and south fork rivers occupy the northeast sides of their respective meander belts the form of the abandoned meander loops within these asymmetric meander belts indicates that they were produced by gradual northeast migration of the active channels this progressive migration can be related to tectonic tilting produced by regional extensional faulting at a high angle to the original channel belt axis which ran down a gently sloping outwash cone asymmetric channel sandstone bodies in the rock record can be recognized by the preferred dip of successive lateral accretion units in meander loops together with soft sediment deformation facies and thickness variations they may indicate tectonic deformation of the sedimentary surface

an osl dated middle and late quaternary sedimentary record in the roer valley graben southeastern netherlands abstract well dated terrestrial sedimentary sequences are important to evaluate the influence of quaternary climate change on continental landscape evolution the roer valley graben southeastern netherlands contains a 35 m thick sedimentary record of middle and late quaternary fluvial aeolian and organic deposits sediment provenance depositional processes and the continuity and timing of deposition were reconstructed sedimentary and geochemical data reveal a change from a fluvial depositional environment to a dominance of aeolian deposits this change may be related to increased tectonic uplift and the onset of large scale volcanism in the ardennes eifel region between 800 and 500 ka the main source of aeolian sediments are quaternary rhine deposits that crop out to the northwest of the study area sedimentation and preservation in the roer valley graben took place under humid surface conditions these conditions occurred 1 in a periglacial climate with permafrost 2 at the transition from a warm temperate to a cool climate dates from two internally consistent quartz optically stimulated luminescence osl age series in the roer valley graben correspond well with the ages of related terrace deposits in the orbitally tuned meuse river terrace flight the osl dates confirm the presence of organic deposits reflecting marine oxygen isotope stage mis 9 or 11 and mis 5e this long terrestrial sequence thus provides input for the fragmentary middle pleistocene record of northwestern europe and forms a possible link between the glacial history of northern europe and the long lake and loess records of eastern and southern europe

fluvial incision and channel downcutting as a response to late glacial and early holocene climate change the lower reach of the river meuse maas the netherlands detailed fieldwork and new extensive 14c dating of residual channel infillings provide data for the reconstruction of the late glacial channel downcutting and incision history of the venlo boxmeer lower reach of the river meuse maas in the southern netherlands within a period of 500 1300 yr after late glacial climatic amelioration the meuse responded to increased discharges and decreased sediment supply by adjusting the width depth ratio of its channels two main phases of channel downcutting are followed by two main phases of floodplain lowering and narrowing indicating net floodplain degradation by the fluvial system as a non linear response to late glacial and early holocene climate change some 1300 yr after initial late glacial warming channels downcut rapidly during the early bolling 13 3 12 5 kyr bp and adopted a high sinuosity meandering style channel downcutting paused around 11 9 kyr bp possibly in response to rising groundwater levels and or the older dryas cooling event between 11 9 and 11 3 kyr bp a new floodplain was formed then lateral erosion took place and initiated a first phase of 2 6 m floodplain lowering during the late allerod gradual climate deterioration during the allerod progressively broke up soils and vegetation cover from 11 3 to 10 9 kyr bp the meuse gradually adjusted to an increased ratio of sediment supply over transport capacity through higher width depth ratios main channels became shallower and adopted a low sinuosity pattern finally culminating in a braided river system during the younger dryas the final holocene warming resulted within 500 yr in renewed rapid channel downcutting by a single low sinuosity channel during the early preboreal followed by a second phase of 1 8 2 8 m floodplain lowering copyright 1999 john wiley sons ltd

weathering of basaltic pebbles in a red soil from sardinia a microsite approach for the identification of secondary mineral phases abstract mineral weathering microsites in a basalt rock derived soil were investigated in the mediterranean environment of south western sardinia an in situ approach frequently used for saprolites and rock investigations was employed to examine the weathering microsites of a soil system this study compared clay phases that formed from the weathering of mineral bearing rock pebbles and soil crystal chemical composition with the goal of evaluating the evolutionary trends of the secondary minerals micromorphological mineralogical xrd and ft ir analyses and microscopic sem eds analyses were carried out on i plagioclase enstatite and glassy features weathered volcanic glass microsystems in rock pebbles embedded in the soil ii clay coatings microsystem connecting the soil rock environment and iii the soil itself eds data were plotted on phase diagrams to evaluate developmental and evolutionary trends of the weathered products the weathering of enstatite and volcanic glass resulted in primarily fe bearing montmorillonites while a mixture of fe bearing smectite and kaolinite developed from plagioclases our results indicated formation of secondary phases in open microsystems where transfers of elements among primary minerals and glass occur by slow diffusion along the network of inter mineral micropores cracks that developed inside the soil rock pebbles acted as direct connections between microsystems and the soil environment clay and fe mn coatings deposited in the cracks are an indication of clay migration the mineralogy of these clay coatings was similar to that of the soil matrix and the fine clays since it is likely that the clay migration processes remain active in guspini soils the further mineralogical similarities of clay coatings and soil fine clays suggest that the transformation of fe smectites into k s mlms occurs in the clay phases during transport prior to deposition into the soil environment indeed the similar mineralogy of the in situ analysed soil matrix and fine clays the youngest soil fraction is interpreted as due to same soil processes suggesting stable environmental conditions in the guspini area

last glacial interglacial cycle in the evolution of river valleys in southern and central poland abstract the last glacial interglacial cycle is represented usually by several cuts and fills which have formed 2 3 terrace steps from the last cold stage and by two or more fills of lateglacial holocene age their number depends on the size of the river valley and the position in the longitudinal profile the sequence of changes reflects shorter stadial interstadial climatic fluctuations generally aggradation dominates during the cooler phases of the vistulian and during the interpleniglacial the most distinct erosional phases occurred during the change from a more oceanic to a more continental climate before the maximum extension of the ice sheet 25 20 ka bp and during the upper pleniglacial lateglacial transition 15 13 ka bp the second phase coincides with the rapid downcutting in the lower course of the main vistula valley which had been blocked earlier by the scandinavian ice sheet in the holocene aggradation prevailed accelerated by anthropogenic soil erosion it was only in the mountain foreland that shorter lived hydrological changes resulted in well expressed several cuts and fills

late glacial sedimentological and morphological changes in a lowland river in response to climatic change the maas southern netherlands the late pleniglacial and late glacial maas valley south of nijmegen contains four terraces three river systems are described based on the morphology of channel scars on these terrace surfaces and by sediment characteristics the river maas reacted to climatic warming at the start of the weichselian late glacial by changing its river system slowly from a braided system to a transitional phase between braiding and meandering and finally to a highly sinuous meandering system the maas reacted rapidly to the younger dryas climate deterioration by again establishing a braiding system at the onset of the holocene the river changed abruptly to a meandering river without a transitional phase the triggering factor for change in the maas river pattern is almost certainly the changing climate in the late glacial gradient lines on the terrace surfaces show that tectonic activity did not modify the morphology of the channels a division of the terraces is shown the morphological sedimentological and petrographical characteristics are presented and the linking of changing fluvial patterns with climatic changes or tectonic movements is discussed 1997 john wiley sons ltd

splitting rivers at their seams bifurcations and avulsion river bifurcations are critical but poorly understood elements of many geomorphological systems they are integralelements of alluvial fans braided rivers fluvial lowland plains and deltas and control the partitioning of water and sediment throughthese systems bifurcations are commonly unstable but their lifespan varies greatly in braided rivers bars and channels migrate splitand merge at annual or shorter timescales thereby creating and abandoning bifurcations this behaviour has been studied mainly bygeomorphologists and fluid dynamicists bifurcations also exist during avulsion the process of a river changing course on afloodplain or in a delta which may take 102 103years and has been studied mainly by sedimentologists this review synthesizesour current understanding of bifurcations and brings together insights from different research communities and different environmen tal settings we consider the causes and initiation of bifurcations and avulsion the physical mechanisms controlling bifurcation andavulsion evolution mathematical and numerical modelling of these processes and the possibility of stable bifurcations we end thereview with some open questions copyright 2012 john wiley sons ltd

fluvial history of the northern upper rhine river southwestern germany during the lateglacial and holocene times abstract three time slices were focused on reconstruction of the lateglacial and holocene landscape evolution in the northern upper rhine rift valley the fluvial history of the northern upper rhine river during the last 15 000 years is characterised by repeated rapid changes of fluvial morphodynamics and sedimentation conditions in consequence the floodplain of the rhine river may be subdivided into three different meander generations which differ mainly on morphological lithological and pedogenetical criteria using complementary dating techniques pollen irsl ams 14c a detailed chronology was obtained for the floodplain sediments e g overbank deposits peat bogs aeolian dune sands of the rhine river and its tributary the neckar river bergstrasen necker while the latter became completely abandoned during the younger dryas period the rhine river probably started meandering at the onset of the allerod period and most likely continued its meandering pattern since the lateglacial the change from the oldest meander generation to the older meander generation occurred during the late phase of the atlantic period however the timing of the onset of the younger meander generation is not known in detail at present probably it started to develop in the late subboreal period or at the transition from the subboreal to the subatlantic period

avulsion the relative roles of autogenic and allogenic processes abstract avulsion the abandonment of all or part of a channel belt in favor of a new course is controlled by both autogenic intrabasinal and allogenic extrabasinal processes however their relative roles are not known well the rhine meuse delta is without doubt the best studied delta regarding holocene avulsion processes based on studies of this delta an overview is given of 1 allogenic and autogenic processes influencing different aspects of avulsion 2 the relative importance of these processes in time and space and 3 observations that can be used to differentiate autogenic and allogenic causes of avulsion the following avulsion parameters are quantified and their allogenic and or autogenic nature are discussed period of activity of channel belts period between beginning and end of overbank sedimentation by the river channel interavulsion period time period between successive avulsions of a channel belt avulsion frequency number of avulsions per time interval in a given area and avulsion location in the rhine meuse delta the period of activity of the holocene channel belts varies considerably but shows no significant trend over time whereas extrabasinal factors climate base level and tectonics changed this suggests that this parameter is mainly autogenic controlled the average interavulsion period increased from 8000 cal yr bp to 2800 cal yr bp and decreased since then significant fluctuations occurred on a shorter time scale a maximum variability in the interavulsion period occurred between 3200 and 1800 cal yr bp this was a time when large channel belts gradually came into existence during this period the avulsion frequency also reached a maximum the long term increasing trend in interavulsion period is related to the decreasing rate of sea level rise the decreasing interavulsion period since 2800 cal yr bp can be explained by increased discharge and sedimentation resulting in an increase in the number of avulsions seven avulsion sequences as predicted by the mackey and bridge mackey s d bridge j s 1995 three dimensional model of alluvial stratigraphy theory and application journal of sedimentary research b65 1 pp 7 31 model may be recorded in the holocene dataset of the rhine meuse suggesting a periodicity of 500 600 yr each avulsion sequence coincides with a peak in the avulsion frequency the periodicity of 500 yr in the avulsion frequency is proposed to be autogenic however there is also a long term trend in the avulsion frequency that can be related to sea level rise and after 3000 14c yr bp to climate change and human influence avulsion locations are not randomly distributed over the delta and are related to the allogenic factors relative sea level rise local tectonics and changes in discharge and sediment load

a new gis approach for reconstructing and mapping dynamic late holocene coastal plain palaeogeography the geomorphological development of holocene coastal plains around the world has been studied since the beginning of the twentieth century from various disciplines resulting in large amounts of data however the overwhelming quantities and heterogeneous nature of this data have caused the divided knowledge to remain inconsistent and fragmented to keep improving the understanding of coastal plain geomorphology and geology cataloguing of data and integration of knowledge are essential in this paper we present a gis that incorporates the accumulated data of the netherlands coastal plain and functions as a storage and integration tool for coastal plain mapped data the gis stores redigitised architectural elements beach barriers tidal channels intertidal flats supratidal flats and coastal fresh water peat from earlier mappings in separate map layers a coupled catalogue style database stores the dating information of these elements besides references to source studies and annotations regarding changed insights using scripts the system automatically establishes palaeogeographical maps for any chosen moment combining the above mapping and dating information in our approach we strip the information to architectural element level and we separate mapping from dating information serving the automatic generation of time slice maps it enables a workflow in which the maker can iteratively regenerate maps which speeds up fine tuning and thus the quality of palaeogeographical reconstruction the gis currently covers the late holocene coastal plain development of the netherlands this period witnessed widespread renewed flooding along the southern north sea coast coinciding with large scale reclamation and human occupation our gis method is generic and can be expanded and adapted to allow faster integrated processing of growing amounts of data for many coastal areas and other large urbanising lowlands around the world it allows maintaining actual data overview and facilitates new ways of analysis at national regional and local scales 2016 elsevier b v

late glacial fluvial response of the niers rhine western germany to climate and vegetation change the niers valley was part of the rhine system that came into existence during the maximum saalian glaciation and was abandoned at the end of the weichselian the aim of the study was to explain the late pleniglacial and late glacial fluvial dynamics and to explore the external forcing factors climate change tectonics and sea level the sedimentary units have been investigated by large scale coring transects and detailed cross sections over abandoned channels the temporal fluvial development has been reconstructed by means of geomorphological relationships pollen analysis and 14c dating the niers rhine experienced a channel pattern change from braided via a transformational phase to meandering in the early late glacial this change in fluvial style is explained by climate amelioration at the late pleniglacial to late glacial transition at ca 12 5 k 14c yr bp and climate related hydrological lithological and vegetation changes a delayed fluvial response of ca 400 14c yr transitional phase was established the channel transformations are not related to tectonic effects and sea level changes successive river systems have similar gradients of ca 35 40 cm km 1 a meandering river system dominated the allerod and younger dryas periods the threshold towards braiding was not crossed during the younger dryas but increased aeolian activity has been observed on the younger dryas point bars the final abandonment of the niers rhine was dated shortly after the younger dryas to holocene transition traces of laacher see pumice have been found in the niers valley indicating that the niers rhine was still in use during the younger dryas copyright 2005 john wiley sons ltd

patterns of alluvial rivers the pattern planform of a river can be considered at vastly different scales depending upon both the size of the river and the part of the fluvial system that is under consideration figure 1 for example in the broadest sense river patterns comprise a drainage network dendritic parallel trellis etc figure la the type of pattern is of interest to geomorphologists and geologists who interpret geologic conditions from aerial photographs at another scale a river reach which in figure lb is meandering is of interest to the geomorphologist who is interested in what that pattern reveals about river history and behavior and to the engineer who is charged with maintaining navigation and preventing major instability when a single meander is examined figure 1 c the hydraulics offtow the sediment transport and the potential for bank erosion are of concern in addition the sedimentologist is interested in the distribution of sediment within the bend bed forms within the channel figure ld and sedimentary structures figure ie which also establish a component of roughness for the hydraulic engineer finally the individual grains figure if provide geologic information on the sediment sources the nature of sediment loads and the feasibility of dredging for gravel there is an interaction of hydrology hydraulics geology and geomorphology at all scales which emphasizes the point that the fluvial system as a whole cannot be ignored even though only a component of the system is to be studied in this review only the patterns or planforms of alluvial rivers are discussed although it is apparent that the hydrologic and sediment yield characteristics of the drainage basin figure la as well as its geologic history cannot be ignored in the explanation of the pattern of any river

basalt weathering and pedogenesis across an environmental gradient in the southern cascade range california usa abstract basalt rocks occupy substantial land area and play a significant role in global weathering patterns and biogeochemical cycling the objective of this research was to quantify climatic controls of weathering and pedogenic processes on basalt derived soils across an environmental gradient on the western slope of the casacade range of california usa we hypothesized that climate controls mineral neogenesis with cool moist conditions favoring formation of short range order sro materials and warm dry conditions favoring smectite crystalline fe oxyhydroxides and kaolins four pedons were sampled across an elevation gradient 250 2500 m having large variation in mean annual soil temperature 5 17 c and mean annual precipitation 750 1350 mm the soil mineral assemblage was characterized by x ray diffraction selective dissolution total elemental analysis and light microscopy the degree of weathering and mineral assemblage exhibited a clear threshold at the permanent winter snowline 1200 m maximum soil development was noted just below the snowline with soils dominated by kaolinite and dehydrated halloysite crystalline fe oxyhydroxides 48 kg m 2 extensive loss of cations chemical index of alteration cia 95 and clay accumulation 447 kg m 2 in contrast the high elevation snow dominated pedons displayed less intense weathering e g cia

long term fluvial archives in nw france response of the seine and somme rivers to tectonic movements climatic variations and sea level changes the seine and the somme are the two main rivers flowing from northwestern france into the channel during the pleistocene cold stages both rivers were tributaries of the river manche which was exporting sediments into the central deeps of the channel the river seine has a very well developed terrace system recording incision that began at around 1 ma the same age is proposed for the beginning of the main incision in the somme valley on the basis of morphostratigraphy pedostratigraphy palaeontology palaeomagnetism and esr datings the uplift rate deduced from analysis of the seine and somme terrace systems is of 55 to 60 m ma since the end of the lower pleistocene the response of the two rivers to climatic variations uplift and sea level changes is complex and variable in the different parts of the river courses for example the evolution of the lower seine system is influenced by uplift and climate changes but dominated by sea level changes in the middle seine the system is beyond the impact of sea level variations and shows a very detailed response to climatic variations during the middle and upper pleistocene in a context of uplift the somme valley response appears to be more homogeneous especially in the middle valley where the terrace system shows a regular pattern in which incision occurs at the beginning of each glacial period against a general background of uplift nevertheless the lower somme valley and the palaeo somme in the channel area indicate some strong differences compared with the middle valley influence of sea level variations and probably differences in rates of tectonic uplift between the channel and the present continent the differences in the responses of the two river valleys during the pleistocene are related to differences in the size of the fluvial basins to the local tectonic characteristics to the geometry of the platform connected to the lower parts of the valleys and to the hydrodynamic characteristics of each river finally it is shown from these examples that the multidisciplinary study of pleistocene rivers is a very efficient tool for the investigation of neotectonic activity

modeling the response of the rhine meuse fluvial system to late pleistocene climate change abstract we use a landscape evolution model to infer the effect of late pleistocene climate change on the incision aggradation behaviour of the rhine meuse fluvial system we model the routing of runoff and sediment in the catchment in order to predict grainsize trends and the incision and aggradation behaviour in the downstream reach where we compare it to the sequence of events and grainsize characteristics inferred from borehole corings this sequence starts with an important incision taking place around the mis 3 to mis 2 climatic transition during the coldest part of mis 2 a coarse grained sedimentary unit is deposited that shows an upward increase in the sand gravel ratio the model experiments do not predict an incision at the mis 3 to mis 2 transition therefore the incision should be attributed to other causes most likely effects of glacio isostatic uplift however a relative upward increase in sand content of the sediments is predicted by the model this increase is the result of the difference in transport rates between sand and gravel starting from a homogeneous pre existing mis 3 deposit the gravel content in the active layer increases because the sand is removed quickly and transported further downstream whereas the gravel travels slowly and piles up with gravel originating from immediately upstream resulting in a net accumulation at a later stage sand originating from much further upstream progrades fan like over the gravelly deposits according to the record during the early late glacial warming part of mis 2 bolling allerod interstadial neither incision nor aggradation has taken place this is in accordance with modelling results which show that despite the reduction of sediment input due to re vegetation of hillslopes sufficient sediment remains available for fluvial transport in the channel network itself it takes several thousands of years before effects of sediment depletion in the catchment are noted downstream that is why we argue that the inferred incision at the late late glacial the start of the younger dryas in our downstream study area might reflect depletion effects related to the preceding early late glacial conditions in general our modelling results show that terraces along one large fluvial system are diachronic features in particular terrace surfaces are older upstream compared to downstream in addition complex responses to climate change are likely to occur in a large fluvial system like the rhine meuse and correlation of morphological features in the fluvial record to specific short term palaeo climatic events for example dansgaard oeschger events could be risky without consideration of catchment size characteristics and associated response times

apparent late quaternary fault slip rate increase in the southern lower rhine graben central europe in regions of low strain long earthquake recurrence intervals 104 106 yrs and erosive processes limit preservation of quaternary markers suitable for distinguishing whether faults slip at uniform or secularly varying rates the lower rhine graben in the border region of germany the netherlands and belgium provides a unique opportunity to explore quaternary slip rate variations in a region of low strain using the basal 2 29 0 29 ma and surface 700 80 ka contacts of the regionally extensive main terrace hauptterrasse deposited by the rhine and maas rivers these surfaces are vertically offset 3 140 m and 0 68 m respectively across individual fault strands within a distributed network of northwest trending slow slipping 80 of the sites record an apparent increase in slip rate for the more recent interval from 700 ka to present which corresponds to a period of increased uplift of the nearby rhenish massif and regional volcanism however the apparent increase in slip rate could result in part from erosion of the footwall surface below the main terrace leading to an apparent displacement that is smaller than the total vertical offset since the start of the quaternary prior work focused on characterization of these faults as seismic sources in the lower rhine graben has preferentially relied on the average fault slip rate constrained using the base of the main terrace we suggest that average fault slip rates calculated using the 700 ka main terrace surface are subjected to fewer uncertainties and sample a time interval that is more relevant for seismic hazard analysis electronic supplement 1 table of main terrace surface and basal contact offset measurements figure describing an unrealistic faulting scenario and a kml file with the fault trace mapping spanning the lower rhine graben 1 http www bssaonline org lookup suppl doi 10 1785 0120160197 dc1

cyclic sedimentation in tertiary lower rhine basin germany the liegendrucken of the brown coal open cast fortuna mine abstract in the lower rhine basin at the northwestern headlands of the schiefergebirge in western germany the oligocene miocene koln formation once was splendidly exposed in the former fortuna mine one of the open cast mines of the regional brown coal mining industry there a complex 60 m thick clastic marine shoreline succession was studied coastal marine sediments were formed along a high energy coast in the basal sediment fill of the basin due to repeated ingressions of the tertiary north sea a number of subtidal to supratidal coastal onlap cycles developed this study provides first knowledge about cyclic sedimentation in the tertiary of the lower rhine basin

fluvial responses to climate and sea level change a review and look forward summary fluvial landforms and deposits provide one of the most readily studied quaternary continental records and alluvial strata represent an important component in most ancient continental interior and continental margin successions moreover studies of the long term dynamics of fluvial systems and their responses to external or allogenic controls can play important roles in research concerning both global change and sequence stratigraphy as well as in studies of the dynamic interactions between tectonic activity and surface processes these themes were energized in the final decades of the twentieth century and may become increasingly important in the first decades of this millennium this review paper provides a historical perspective on the development of ideas in the fields of geomorphology quaternary geology vs sedimentary geology and then summarizes key processes that operate to produce alluvial stratigraphic records over time scales of 103 106 years of particular interest are changes in discharge regimes sediment supply and sediment storage en route from source terrains to sedimentary basins as well as changes in sea level and the concept of accommodation late quaternary stratigraphic records from the loire france mississippi usa colorado texas usa and rhine meuse the netherlands rivers are used to illustrate the influences of climate change on continental interior rivers as well as the influence of interacting climate and sea level change on continental margin systems the paper concludes with a look forward to a bright future for studies of fluvial response to climate and sea level change at present empirical field based research on fluvial response to climate and sea level change lags behind a the global change community s understanding of the magnitude and frequency of climate and sea level change b the sequence stratigraphic community s desire to interpret climate and especially sea level change as forcing mechanisms and c the modelling community s ability to generate numerical and physical models of surface processes and their stratigraphic results a major challenge for the future is to catch up which will require the development of more detailed and sophisticated quaternary stratigraphic sedimentological and geochronological frameworks in a variety of continental interior and continental margin settings there is a particular need for studies that seek to document fluvial responses to allogenic forcing over both shorter 102 103 years and longer 104 106 years time scales than has commonly been the case to date as well as in larger river systems from source to sink studies of quaternary systems in depositional basin settings are especially critical because they can provide realistic analogues for interpretation of the pre quaternary rock record

regional paleoprecipitation records from the late eocene and oligocene of north america abstract the marine 18o record indicates precipitous cooling or significant expansion of antarctic ice volume across the eocene oligocene epoch boundary at 33 7 ma this climatic step is also found in estimates of decreased paleoprecipitation from paleosols in oregon montana and nebraska but is only a part of a long term decline across the eocene oligocene transition rather than a sudden shift this suggests that climate was driven by a gradual process rather than a single perturbation paleoprecipitation levels stabilized during the oligocene coincident with a stabilization in 18o values possibly indicating a new climatic steady state

industrial mineral occurrences associated with cenozoic volcanic rocks of sardinia italy geological mineralogical geochemical features and genetic implications the most important industrial mineral im deposits associated with the cenozoic volcanics of sardinia include kaolin bentonite and zeolites though of less significance perlite and potassium feldspar are also important in local and national markets bentonite and to a lesser extent kaolin and perlite form economically viable deposits and zeolites appear as very important industrial mineral commodities for future economic development the market situation for potassium feldspar is still under evaluation for use in ceramics all these deposit types occur as alteration products of cenozoic volcanic rocks which were emplaced during three main volcanic cycles in the eocene ec 55 to 51 ma oligocene miocene omc 32 to 13 ma and pliocene pleistocene ppc 5 to 0 1 ma kaolin bentonite zeolites and potassium feldspar occur as alteration products of the omc volcanites perlite occurs as an alteration product of the ppc volcanites all deposits have generally derived from the alteration of the most acidic members of the cenozoic volcanic rocks rhyolites to rhyodacites but differences among the associated ore forming phenomena are recognized hydrothermal sensu stricto deuteric alteration and weathering are the most important processes involved in ore formation weathering although of minor importance can also contribute to enhance the alteration of the deposits formed by hydrothermal and deuteric processes the extent and type of occurrences are mainly controlled by the local geological and structural features and the environmental geochemical conditions kaolin occurs in three main districts at romana and tresnuraghes it is hosted within ignimbritic sequences while at serrenti furtei it is found in pyroclastic flows and ash flow tuffs kaolin formed by hydrothermal processes occurs in high sulfidation romana and serrenti furtei and low sulfidation tresnuraghes type epithermal systems the alteration is proximal to the feeder conduits and structural setting controls kaolin formation bentonite is widespread throughout sardinia deposits occur as stratiform mineral bodies in situ altered within poor welded pumice rich and ash rich layers and also as distal fall out deposits as lenticular bodies interlayered within the miocene sedimentary sequences the former originated by deuteric alteration and formation is mainly controlled by lithology whereas the second type originated by weathering which altered the volcanic ash lenses deposited in lacustrine and or fluvial deltaic environments

clay mineralogy and its relationship to soil solution composition in soils from different weathering environments of humid asia japan thailand and indonesia abstract we studied the relationship between the clay mineralogy of subsurface soils from 204 sites and their water extracts in upland soils of humid asia japan thailand and indonesia to understand their formation the clay minerals were identified by xrd and the kaolin minerals and gibbsite were quantified with dta their thermodynamic stability was related to the ion activity of soil water extracts in soils on mica free andesitic or mafic parent material kaolin minerals and smectite dominated in all regions among mica containing soils derived from felsic or sedimentary rocks mineralogical and soil solution compositions indicate that in thailand mica was stable at high ph 5 4 6 5 whereas in soils from japan and indonesia mica turned into hydroxy al interlayered vermiculite hiv or vermiculite at lower ph 4 3 5 5 in japanese soils hiv and gibbsite form under high activity of al oh species in contrast the low activity of al oh species in indonesian soils resulted in the dissolution of al hydroxides between 2 1 layers and gibbsite and the dominance of kaolin minerals and vermiculite we conclude that three factors play an important role for the clay mineralogy in humid asia the nature of parent material i e presence or absence of mica soil ph as affected by precipitation and evapotranspiration and activity of al oh species in soil solution reflecting soil age

the impact of land use and climate change on late holocene and future suspended sediment yield of the meuse catchment abstract in this study we investigate the relative importance of changes in land use and climate on suspended sediment yield sy on millennial timescales in the meuse basin we use a spatially distributed soil erosion and sediment delivery model watem sedem to simulate sy in three time periods 4000 3000 bp minimal anthropogenic influence 1000 2000 ad includes land use and climate change and the 21st century changes in climate are based on climate model output ecbilt clio vecode for the 21st century the model is forced according to two emission scenarios of the intergovernmental panel on climate change ipcc namely the sres scenarios a2 and b1 these scenarios lie towards the higher and lower end of the full ipcc scenario range respectively for 4000 3000 bp the basin is assumed to be almost fully forested for 1000 2000 ad land use is reconstructed using corine data historical sources and land use modelling and for the 21st century land use is based on the european land use change project eururalis whilst rainfall erosivity increases by only 3 between 4000 3000 bp and 1000 2000 ad sy increases from ca 92 000 mg a 1 to ca 306 000 mg a 1 this model prediction is in agreement with the limited regional multi proxy data available our simulations show that almost all of this increase is due to the conversion of forest to agricultural land over the period 1000 1900 ad sy shows a significant increasing trend with a peak of ca 388 000 mg a 1 in the 19th century due to continuing deforestation in the 20th century reforestation and rapid urbanisation result in a decrease to ca 281 000 mg a 1 sensitivity analyses show that although land use change acts as the primary control on long term changes in sy the sensitivity of sy to changes in climate increases as the percentage of deforested land increases for the 21st century the results are highly sensitive to the scenarios used due to relatively large increases in rainfall erosivity sy increases by 12 compared to the 20th century according to scenario a2 or by 8 according to b1 however the associated land use change scenarios cause decreases in sy by 26 a2 and 46 b1 the net effect is thus a decrease of sy this study highlights the potentially significant efficacy of land use planning as a tool to mitigate the negative effects of soil erosion and sediment delivery to rivers

spatial variation of overbank aggradation rate and its influence on avulsion frequency river avulsions are commonly considered to be driven by the aggradation and growth of alluvial ridges and the associated increase in cross valley slope relative to either the down channel slope or the down valley slope the latter is termed the slope ratio in the present paper therefore spatial patterns of overbank aggradation rate over stratigraphically relevant time scales are critical in avulsion dominated models of alluvial architecture detailed evidence on centennial to millennial scale floodplain deposition has to date been largely unavailable new data on such long term overbank aggradation rates from the rhine meuse and mississippi deltas demonstrate that the rate of decrease of overbank deposition away from the channel belt is much larger than has been supposed hitherto and can be similar to observations for single overbank floods this leads to more rapid growth of alluvial ridges and more rapid increase in slope ratios potentially resulting in increased avulsion frequencies a revised input parameter for overbank aggradation rate was used in a three dimensional model of alluvial architecture to study its effect on avulsion frequency realistic patterns of avulsion and interavulsion periods 1000 years were simulated with input data from the holocene rhine river with avulsions occurring when the slope ratio is in the range 3 5 however caution should be practised with respect to uncritical use of these numbers in different settings evidence from the two study areas suggests that the avulsion threshold cannot be represented by one single value irrespective of whether critical slope ratios are used as in the present study or superelevation as has been proposed by other investigators

geomorphic and sedimentary response of rivers to tectonic deformation a brief review and critique of a tool for recognizing subtle epeirogenic deformation in modern and ancient settings abstract rivers are extremely sensitive to subtle changes in their grade caused by tectonic tilting as such recognition of tectonic tilting effects on rivers and their resultant sediments can be a useful tool for identifying the often cryptic warping associated with incipient and smaller scale epeirogenic deformation in both modern and ancient settings tectonic warping may result in either longitudinal parallel to floodplain orientation or lateral normal to floodplain orientation tilting of alluvial river profiles alluvial rivers may respond to deformation of longitudinal profile by 1 deflection around zones of uplift and into zones of subsidence 2 aggradation in backtilted and degradation in foretilted reaches 3 compensation of slope alteration by shifts in channel pattern 4 increase in frequency of overbank flooding for foretilted and decrease for backtilted reaches and 5 increased bedload grain size in foretilted reaches and decreased bedload grain size in backtilted reaches lateral tilting causes down tilt avulsion of streams where tilt rates are high and steady down tilt migration combing where tilt rates are lower each of the above effects may have profound impacts on lithofacies geometry and distribution that may potentially be preserved in the rock record fluvial sedimentary evidence for past tilting is traditionally based on the assumption that depositional features reminiscent of modern fluvial tectonic effects are evidence for past tectonic effects where it is closely associated with historically active structures or where non tectonic causes cannot be invoked however caution must be exercised when using these effects as criteria for past or current tectonic warping as these effects may be caused by non tectonic factors these non tectonic causes must be eliminated before tectonic interpretations are made

climatically controlled river terrace staircases a worldwide quaternary phenomenon a comparison of fluvial terrace sequences from around the world based on data collected as part of international geoscience programme igcp project no 449 has revealed significant patterns river terraces provide important records of uplift which is essential for their formation and of landscape evolution their cyclic formation however almost invariably seems to have been a response to climatic fluctuation sequences in the european core area of igcp 449 which has the longest and most extensive research history have been used as templates for worldwide comparison there is evidence for a global acceleration of uplift at the time of and perhaps in response to the mid pleistocene revolution when climatic fluctuation switched to 100 kyr milankovitch cycles terraces formed prior to this generally consist of wide aggradational sheets that probably each represent formation over several 41 kyr cycles subsequently river valleys became more steeply entrenched and terraces formed in response to the stronger 100 kyr climatic forcing in many cases at approximately one per cycle this paper uses the new data resource to explore differences between records in different climate zones between sequences with variable numbers of middle late pleistocene terraces and between systems in which the all important incision event has occurred in different parts of climatic cycles key records discussed include european examples from the rhine thames somme dniester dnieper don volga and aguas from asia the gediz turkey and orontes syria from north america the south platte and colorado from south africa the vaal and sundays from australia the shoalhaven and from south america the amazon paraguay and tributaries of the colorado and negro

axial river evolution in response to half graben faulting carson river nevada u s a abstract the holocene history of faulting and river channel movement for the carson valley nevada allows the tectonic alluvial interactions of an active half graben to be studied topographic surveys maps cores radiocarbon dates and paleohydrology are used to study the temporal and spatial patterns of carson river channel change the influence of faulting and associated ground tilting on channel movement is determined by comparing the pattern and timing of river movements with the published event history of the basin bounding fault inverse modeling of the fault history assuming rigid block motion suggests that surface gradients perpendicular to the channel and basin axis have progressively increased through the holocene from an initially horizontal surface the greater part of this movement occurred during and immediately after faulting channel avulsion in response to this increased tectonic ground tilting appears to be the most important factor controlling alluvial architecture although intrinsic fluvial processes and regional climate change may have triggered individual avulsions channel belts avulsed towards the fault onlap after each tectonic event during periods of tectonic quiescence they migrated away from the fault offlap taking the path of maximum overall gradient lag times between faulting and channel avulsion are very short instantaneous to hundreds of years the observed holocene history of the carson river is consistent with positions of channel belts predicted by half graben stratigraphic models and therefore this study provides the first confirmation that the underlying alluvial tectonic assumptions of these models are broadly correct

timescales climate and river development abstract in the long term glacial interglacial sequences river development follows general climatic evolution however at the scale of one cold warm cycle it appears that the geomorphological effect of river activity is best expressed at times of climatic change such periods of pronounced fluvial action last only a short time in more detail the internal evolution in a drainage basin after a climatic event results in a delayed response of the morphology and sedimentation pattern finally on the shortest timescale local thresholds may play a decisive role in the reactions of river systems it is concluded that the relation between fluvial development and climate is not a simple one but is fundamentally dependant on the timescale

spatial and temporal variations in river terrace formation preservation and morphology in the lower meuse valley the netherlands the lower meuse valley crosses the roer valley rift system and provides an outstanding example of well preserved late glacial and holocene river terraces the formation preservation and morphology of these terraces vary due to reach specific conditions a phenomenon that has been underappreciated in past studies a detailed palaeogeographic reconstruction of the terrace series over the full length of the lower meuse valley has been performed this reconstruction provides improved insight into successive morphological responses to combined climatic and tectonic external forcing as expressed and preserved in different ways along the river new field data and data obtained from past studies were integrated using a digital mapping method in gis results show that late glacial river terraces with diverse fluvial styles are best preserved in the lower meuse valley downstream sub reaches traversing the venlo block and peel block while holocene terrace remnants are well developed and preserved in the upstream sub reaches traversing the campine block and roer valley graben this reach to reach spatial variance in river terrace preservation and morphology can be ascribed to tectonically driven variations in river gradient and subsurface lithology and to river driven throughput of sediment supply

zeolites in soil environments the limited occurrence of these minerals has resulted in a scant knowledge about their properties in the soils zelazny and calhoun 1977 as pointed out by the above authors the occurrence of natural zeolites in soils is rare and not well known and only about 75 papers have been published describing the occurrence of zeolites in soils these occurrences range from hot humid soils in india to cold arid soils in the dry valleys of antarctica most of these reports describe residual zeolite phases that have persisted from the parent material during soil formation however there are reports of zeolites that have formed in soil environments a variety of natural zeolites have been found in soils including analcime chabazite clinoptilolite gismondine laumontite mordenite natrolite phillipsite and stilbite over the past 25 years natural zeolites have been examined for a variety of agricultural and environmental applications because of their unique cation exchange adsorption and molecular sieving properties and their abundance in near surface sedimentary deposits natural zeolites have been used as soil conditioners slow release fertilizers carriers for insecticides and herbicides remediation agents in contaminated soils and dietary supple ments in animal nutrition ming and allen this volume pond 1995 these applications can result in direct or indirect incorporation of natural zeolites into soils if these minerals are to be used effectively in these applications it will be necessary to understand the long term stability and effects of zeolites in soils or soil like systems several reviews have been published on the occurrences and properties of zeolites in soils zelazny and calhoun 1977 ming and dixon 1987c ming and dixon 1988 ming and mumpton 1989 boettinger and graham 1995 this chapter provides an overview and update on the occurrence of zeolites in soils and briefly describes methodology used for identifying and characterizing zeolites

pseudo 3d imaging of a low slip rate active normal fault using shallow geophysical methods the geleen fault in the belgian maas river valley in a detailed site survey for paleoseismic trenching we applied shallow geophysical prospecting techniques including ground penetrating radar gpr electric resistivity tomography ert and resistivity mapping to identify locate and visualize in 3d the geleen fault an active normal fault bordering the roer valley graben in northeast belgium because of a low slip rate the geomorphic expression of this fault is very faint in the relatively young deposits of the maas river valley ert profiles show the fault as a broad near vertical anomaly characterized by sharp lateral resistivity contrasts with an associated vertical offset of sediment layers we observed offsets of 15 m and 5 m for the base and top respectively of a middle late pleistocene fluvial gravel layer shallow ert and gpr profiles indicate that younger sediments are also affected by faulting but the amount and sense of offset appear to be conflicting ert profiles show a near surface high resistivity layer with an apparent rever

late quaternary activity of the feldbiss fault zone roer valley rift system the netherlands based on displaced fluvial terrace fragments abstract the meuse river crosses the feldbiss fault zone one of the main border fault zones of the roer valley graben in the southern part of the netherlands uplift of the area south of the feldbiss fault zone forced the meuse river to incise and as a result a flight of terraces was formed faults of the feldbiss fault zone have displaced the middle and late pleistocene terrace deposits in this study an extensive geomorphological survey was carried out to locate the faults of the feldbiss fault zone and to determine the displacement history of terrace deposits the feldbiss fault zone is characterized by an average displacement rate of 0 041 0 047 mm a 1 during the late pleistocene individual faults show an average displacement rate ranging between 0 010 and 0 034 mm a 1 the spatial variation in displacement rates along the individual faults reveals a system of overstepping faults these normal faults developed by reactivation of paleozoic strike slip faults as fault displacements at the bases of the younger terrace deposits are apparently similar to the tops of the adjacent older terrace the age of these horizons is the same within thousands of years this implies that the model of terrace development by rapid fluvial incision followed by slow aggradation does apply for this area

characterization and quantification of active faulting in the roer valley rift system based on high precision digital elevation models the roer valley rift system rvrs is located in the northern prolongation of the upper rhine graben during the cenozoic the evolution of the rvrs was influenced by two different rift systems situated in the north and in the south the north sea rift system and the west european rift system respectively during the last decades moderate seismicity revealed the continuous activity of the graben border faults the peel boundary fault zone pbfz and the feldbiss fault zone ffz we use a high precision digital elevation model dem to characterize and quantify the present day deformation along these faults the fault pattern shows similarity to a strike slip structure however analysis of the dem reveals that the recent to quaternary formations and landforms affected by the fault activity are only vertically offset this suggests a pure normal faulting mode for the main border faults and a direction of extension perpendicular to the graben i e ne sw quantification of the offset dated markers allows the determination of the displacement rates along the fault segments in the southeastern part of the rvrs the vertical displacement rates inferred for the ffz and the southeastern pbfz range between 55 and 65 mm ky and around 65 mm ky respectively in contrast the displacement rates determined for the northwestern segment of the pbfz are around 200 mm ky we explain these differences between the northwestern and southeastern parts of the rvrs by the large scale geometry of the graben the rvrs being symmetric in the south east and asymmetric half graben in the north west the deformation is accommodated by two border faults ffz and the south eastern part of the pbfz in the south east and by only one fault in the north west the north western segment of the pbfz in addition the thickness of the neogene main depocentre in the northwestern half of the rvrs indicates a larger amount of extension in this part of the graben than in the south east the combination of the graben geometry and the amount of extension can explain the differences in the displacement rate

geological and geophysical evidence for large palaeo earthquakes with surface faulting in the roer graben northwest europe from the analysis of geological geodetic and geophysical data we provide clear evidence of seismogenic faults capable of producing large earthquakes in intraplate europe previous studies paulissen vandenberghe gullentops 1985 van den berg et al 1994 geluk et al 1994 have yielded some constraints on the rate of crustal deformation along the roer valley a graben structure crossing the netherlands belgium and germany and have allowed us to address the fundamental questions can intraplate earthquakes rupture the surface in this part of stable continental europe and if so what is their return period detailed palaeoseismic investigations have been carried out in belgium along a 10 km long fault scarp which is the morphological expression of the feldbiss fault the southwestern border fault of the roer graben camelbeeck meghraoui 1996 the scarp is multiple and the frontal fault scarp offsets young deposits and alluvial terraces field investigations using geological and geomorphological methodologies combined with geophysical prospecting provide evidence of holocene seismic surface faulting from 14c dating it is suggested that the last earthquake along the fault scarp occurred between 610 ad and 890 ad levelling profiles across the scarp suggest that it produced a vertical coseismic displacement of 0 5 1 m along the scarp if we suppose that the last surface faulting earthquake ruptured the whole seismogenic layer 17 km thickness over a minimum length 10 km corresponding to the length of the bree scarp with an average slip of 0 6 m its seismic moment was at least 3 1 1018 n m mw 6 3 for an average rigidity 3 1010 pa by estimating the offset of the main terrace of the maas river by slippage along the feldbiss fault we calculate the average late pleistocene vertical deformation rate as 0 08 0 04 mm yr 1 palaeoseismic information combining the trench and geomorphic observations suggests the occurrence of two surface faulting earthquakes during the last 20 kyr a third dates before 28 35 kyr bp then if the time distribution of earthquakes is uniform a return period of 12 5 ka and a vertical deformation rate of 0 06 0 04 mm yr 1 are inferred

human and climate impact on catchment development during the holocene geul river the netherlands interest in the holocene development of small to medium sized river catchments in western and central europe in relation to changes in land use and climate has increased over the past years in this study we reconstruct the holocene landscape development and fluvial dynamics of the geul river the netherlands and the main forcing mechanisms of environmental change field studies were carried out and we used osl and 14c dating methods to reconstruct the holocene valley development our study shows that 2 periods of deforestation during the roman period and the high middle ages led to severe soil erosion and increased floodplain sedimentation in the catchment of the geul river possibly combined with periods of increased wetness during the high middle ages alluvial fans have been active since the roman deforestation phase our results show that the geul catchment is highly sensitive to changes in land use

fluvial terrace formation in the northern upper rhine graben during the last 20 000 years as a result of allogenic controls and autogenic evolution abstract the northern upper rhine graben hosts a well preserved late weichselian and holocene fluvial terrace sequence terraces differ in elevation morphology and overbank sediment characteristics the purpose of this study was to determine the relative importance of allogenic controlling factors versus autogenic evolution on the successive formation of these terraces for a representative valley segment the gernsheim region results from previous research were integrated with newly obtained borehole data and digitized elevation maps to construct palaeogeographic maps and cross sections coarse grained channel deposits below terrace surfaces were dated using optically stimulated luminescence and fine grained abandoned channel fill deposits were dated using pollen stratigraphy and radiocarbon analysis initiation of terrace formation was caused by climatic change in the late pleniglacial after 20 ka but fluvial response was complex and slow and continued locally until the middle boreal 9 ka early to middle holocene 6 ka changes in fluvial style and associated overbank lithofacies are not necessarily controlled by climatic change as was previously proposed instead autogenic processes combined with river reach specific factors explain the observed terrace development continuous incision autogenic evolution and high preservation potential provide an alternative explanation for the presence of a terrace sequence in this subsiding area