tsunami observations in rivers from a perspective of tsunami interaction with tide and riverine flow the observations of the 2011 tohoku tsunami and the 2010 chilean tsunami in several rivers in japan and in the columbia river in the usa are analyzed for patterns of tsunami behavior in river environments tsunamis in rivers exhibit actions very different from those observed on an open coast but very similar among different rivers though the action scale in different rivers varies greatly we describe two tsunami effects in rivers as observed in field data first the river tide modulates the tsunami wave in a very specific way common to all rivers second a strong near field tsunami can cause significant prolonged water accumulation in lower river reaches both effects are inherent in tidal river environments and have been reproduced numerically in a simplified 1 d river using a non linear shallow water model with bottom friction the numerical experiments highlight the indispensable role of a tsunami s interaction with tide and riverine flow

validation and verification of a numerical model for tsunami propagation and runup a robust numerical model to simulate propagation and runup of tsunami waves in the framework of non linear shallow water theory is developed the numerical code adopts a staggered leapfrog finite difference scheme to solve the shallow water equations formulated for depth averaged water fluxes in spherical coordinates a temporal position of the shoreline is calculated using a free surface moving boundary algorithm for large scale problems the developed algorithm is efficiently parallelized employing a domain decomposition technique the developed numerical model is benchmarked in an exhaustive series of tests suggested by noaa we conducted analytical and laboratory benchmarking for the cases of solitary wave runup on simple beaches runup of a solitary wave on a conically shaped island and the runup in the monai valley okushiri island japan during the 1993 hokkaido nansei oki tsunami in all conducted tests the calculated numerical solution is within an accuracy recommended by noaa standards we summarize results of numerical benchmarking of the model its strengths and limits with regards to reproduction of fundamental features of coastal inundation and also illustrate some possible improvements

some tsunami characteristics deducible from tide records abstract after an initial 40 hour diffusion period the time decay of tsunami variance was found to be uniformly exponents for 28 events among eight pacific tide stations thew results essentially confirm munk s acoustic deny hypothesis except that the decay e folding time 22 h more nearly equated the ocean s normal mode transit time 21 h than munk s mean collision time 14 h relative tsunami energy obtained by extrapolating exponential decay back to t 0 was found to be similarly ranked among tsunamis at all stations and roughly proportional to seismic energy a total energy estimate for the tsunami of 9 march 1957 obtained by correcting the observed energy decay at wake island for instrument and island response provided normalized total energy estimates for all tsunamis that were consistent with independent estimates by kajiura and by aida similarities between power spectra computed from these time series suggests that station response is primarily linear normal mode forcing of the conti

dam to delta sediment inputs and storage in the lower trinity river texas livingston dam on the trinity river in se texas usa disrupts the transport of sediment to the lower trinity river and the trinity bay galveston bay estuary however a sediment budget of the lower basin shows that the effects of this disruption are undetectable in the lower river sediment trapped in lake livingston is partly offset by channel erosion downstream of the dam and by inputs from the lower basin most importantly however the lower coastal plain reaches of the trinity are characterized by extensive alluvial storage and are a bottleneck that buffers the bay from effects of upstream changes in sediment flux storage is so extensive that the upper trinity basin and the lowermost river reaches were essentially decoupled in the sense that very little upper basin sediment reached the lower river long before the dam was constructed whereas sediment storage in lake livingston is extensive alluvial storage on the trinity flood plain is even more extensive dam related sediment starvation effects are noted for about 52 km downstream and the sediment budget suggests that a majority of the sediment in this reach is likely derived from channel scour and bank erosion the capacious alluvial storage in the lower trinity not only limits flux to the bay but the large amount of remobilizable alluvium also allows the system to adjust to localized sediment shortages as illustrated in the dam to romayor reach internal adjustments within the lower trinity river valley thus buffer the bay from changes in sediment supply upstream

model analyses of the contribution of in channel processes to sediment concentration hysteresis loops summary sediment concentration sc water discharge q relations in rivers are typically governed by multiple and relatively complex processes due to hysteresis effects sediment discharges can differ for similar or equivalent water discharges which causes scatter in empirical datasets and may decrease the predictive power of sc rating curves such hysteresis effects must therefore be understood and accounted for to make dependable predictions for river system management the overall objectives of this study are to develop modelling approaches suitable for reproducing and predicting hysteresis effects at larger scales and to investigate the possible contribution of in channel processes erosion and deposition to sediment concentration hysteresis loops to investigate relevant field scale conditions we develop a one dimensional dynamic sediment transport model of the downstream tuul river northern mongolia investigating in channel processes along a 141 km stretch during a hydrological year the results show that the present modelling approach can reproduce both anti clockwise and clockwise hysteresis effects importantly in channel processes alone can cause considerable anti clockwise hysteresis effects without being reinforced by catchment processes such as hillslope erosion such specific contributions from in channel processes introduced data scatter into the sediment rating curves decreasing their r 2 values from unity to approximately 0 5 to 0 6 more generally possible changes in the number or magnitude of high flow events caused by climatic or other anthropogenic factors could influence total sediment deposition which was primarily found to occur during relatively short high flow events such potential changes also have important implications for the possible spreading of polluted sediments

variations in trace element geochemistry in the seine river basin based on floodplain deposits and bed sediments between 1990 and 1995 a series of bed sediment suspended sediment and fresh floodplain samples were collected within the seine river basin in france to evaluate variations in trace element geochemistry average background trace element levels for the basin were determined from the collection and subsequent analyses of bed sediment samples from small rural watersheds and from a prehistoric 5000 bp site in paris concentrations are relatively low and similar to those observed for fine grained bed sediments from unaffected areas in the united states and canada however the concentrations are somewhat higher than the reference levels presently adopted by french water authorities for areas north of the seine basin which have similar bedrock lithologies downstream trace element variations were monitored in 1994 and 1995 using fresh surficial floodplain samples that were collected either as dried deposits a few days after peak discharge or immediately after peak discharge under 30 cm of water chemical comparisons between fresh floodplain deposits and actual suspended sediments collected during flood events indicate that with some caveats the former can be used as surrogates for the latter the floodplain sediment chemical data indicate that within the seine basin from the relatively unaffected headwaters through heavily affected urban streams trace element concentrations vary by as much as three orders of magnitude these trace element changes appear to be the result of both increases in population as well as concomitant increases in industrial activity this article is a us government work and is in the public domain in the united states

man s influence on the erosion and transport of sediment by asian rivers the yellow river huanghe example during the holocene sediment input from the yellow river to the yellow sea and adjacent areas has amounted to about 3000 km 3 detailed records from river gauging stations over the past 70 yrs together with estimates based on earlier historic records suggest that the river has contributed 2300 km 3 of sediment during the last 2300 yrs an average discharge of 1 km 3 yr 1 x 10 9 t yr prior to extensive agricultural use of the loess plateau in northern china beginning about 200 bc therefore the river s load must have been about 0 1 km 3 yr an order of magnitude lower than that at present a broad delta 20 m below sea level suggests that early holocene rates were higher than the pre agricultural average and therefore that middle holocene loads were low

comparison of sediment supply to san francisco bay from watersheds draining the bay area and the central valley of california article i nfo quantifying suspended sediment loads is important for managing the world s estuaries in the context of nav igation pollutant transport wetland restoration and coastal erosion to address these needs a comprehen sive analysis was completed on sediment supply to san francisco bay from fluvial sources suspended sediment optical backscatter velocity data near the head of the estuary and discharge data obtained from the output of a water balance model were used to generate continuous suspended sediment concentration records and compute loads to the bay from the large central valley watershed sediment loads from small tributary watersheds around the bay were determined using 235 station years of suspended sediment data from 38 watershed locations regression analysis and simple modeling over 16 years net annual suspended sediment load to the head of the estuary from its 154 000 km 2 central valley watershed varied from 0 13 to

human impact on land ocean sediment transfer by the world s rivers abstract land ocean transfer of sediment by rivers is a key pathway for material transfer on earth contemporary data on the sediment loads of rivers provide clear evidence of significant recent changes in the sediment fluxes of several rivers in response to human impact the key drivers of increased sediment loads include land clearance for agriculture and other facets of land surface disturbance including logging activity and mining although programmes for soil conservation and sediment control can result in reduced sediment loads the trapping of sediment by dams represents the dominant cause of reduced loads this influence is currently assuming increasing importance at the global scale any attempt to link these drivers to changes in the global land ocean sediment flux must take account of the aggregation and buffering effects that operate in larger basins which can cause damping and even removal of signals of increasing flux within the upstream basin and complicate the link between upstream and downstream response to human impact further work is required to provide a precise quantitative assessment of the human impact on global land ocean sediment fluxes and the net effect of increasing and decreasing fluxes particular attention must be paid to the temporal perspective and the variation of impact trajectories in different areas of the globe and for river basins of different sizes

world wide delivery of river sediment to the oceans new data and new estimates from old data show that rivers with large sediment loads annual discharges greater than about 15 times 10 6 tons contribute about 7 times 10 9 tons of suspended sediment to the ocean yearly extrapolating available data for all drainage basins the total suspended sediment delivered by all rivers to the oceans is about 13 5 times 10 9 tons annually bedload and flood discharges may account for an additional 1 2 times 10 9 tons about 70 of this total is derived from southern asia and the larger islands in the pacific and indian oceans where sediment yields are much greater than for other drainage basins

holocene environmental change and its impact on sediment dynamics in the eastern mediterranean abstract investigators have studied past environmental change in the eastern mediterranean region from a number of perspectives while climate reconstructions and palynological research have focused on forces that drive the geomorphologic system many researchers have attempted to use sediment archive studies to identify periods of change in sediment dynamics due to the large variability in environmental parameters and the variety of landscapes present in the eastern mediterranean region research has focused on sediment archives ranging from small colluvial sites to deltas of large rivers on the mediterranean coast as the cultural record for the region is extremely rich the main goal of palaeo environmental research in the eastern mediterranean has been to identify the relative importance of human impact on the landscape nevertheless sediment archives have significant limitations chronological control for many palaeo environmental records is highly uncertain and rates of landscape change are oftentimes difficult to assess most palaeo environmental research has been conducted on or near archeological sites where direct human impact may obscure the indirect impact on sediment dynamics through land use changes quantification and modeling of sediment dynamics in the eastern mediterranean environment offer one solution when erosion and sediment transport rate analyses are incorporated periods of relatively important change can be identified using multiple approaches the relative importance of the main driving forces climate and land use become distinguishable since field based data from the actual sediment archives remain vital an overview of numerous studies in the eastern mediterranean is provided in order to draw a general picture for different time periods and the relative scale of regional landscape development during the holocene a comparison of sediment dynamics with the record of driving forces indicates that while climate was the main driver of the geomorphic system during the early holocene at some point human impact became widespread and began to dictate sediment dynamics to a large extent from the byzantine period onward soil properties seem to play an increasingly important role as the hillslope soil reservoir in the eastern mediterranean was progressively depleted during the late holocene

the effects of hurricane irene and tropical storm lee on the bed sediment geochemistry of u s atlantic coastal rivers hurricane irene and tropical storm lee both of which made landfall in the u s between late august and early september 2011 generated record or near record water discharges in 41 coastal rivers between the north carolina south carolina border and the u s canadian border despite the discharge of substantial amounts of suspended sediment from many of these rivers as well as the probable influx of substantial amounts of eroded material from the surrounding basins the geochemical effects on the 63 m fractions of the bed sediments appear relatively limited 20 of the constituents determined 256 out of 1394 based on surface area measurements this lack of change occurred despite substantial alterations in both the grain size distribution and the composition of the bed sediments the sediment associated constituents which display both concentration increases and decreases include total sulfur ts hg ag total organic carbon toc total nitrogen tn zn se co cu pb as cr and total carbon tc as a group these constituents tend to be associated either with urbanization elevated population densities and or wastewater solid sludge the limited number of significant sediment associated chemical changes that were detected probably resulted from two potential processes 1 the flushing of in stream land use affected sediments that were replaced by baseline material more representative of local geology and or soils declining concentrations and or 2 the inclusion of more heavily affected material as a result of urban nonpoint source runoff and or releases from flooded treatment facilities increasing concentrations published 2013 this article is a u s government work and is in the public domain in the usa

the sediment delivery problem abstract the linking of on site rates of erosion and soil loss within a drainage basin to the sediment yield at the basin outlet and improved knowledge and representation of the associated processes of sediment delivery represent a major research need within the field of erosion and sedimentation and also an important scale problem in drainage basin studies this paper reviews the limitations of the sediment delivery ratio concept by considering the problems of temporal and spatial lumping and its blackbox nature some recent advances in our understanding of the sediment delivery system and its modelling are described and the lack of detailed empirical investigations is highlighted the significance of recent concern for the role of sediments in the transport of nutrients and contaminants to sediment delivery studies is introduced and the need for further work in this field is emphasised

a response function approach for rapid far field tsunami forecasting predicting tsunami impacts at remote coasts largely relies on tsunami en route measurements in an open ocean in this work these measurements are used to generate instant tsunami predictions in deep water and near the coast the predictions are generated as a response or a combination of responses to one or more tsunameters with each response obtained as a convolution of real time tsunameter measurements and a pre computed pulse response function prf practical implementation of this method requires tables of prfs in a 3d parameter space earthquake location tsunameter forecasted site examples of hindcasting the 2010 chilean and the 2011 tohoku oki tsunamis along the us west coast and beyond demonstrated high accuracy of the suggested technology in application to trans pacific seismically generated tsunamis

rates of flood plain sedimentation on the central amazon river field measurements of water and sediment discharge and floodplain topography numerical simulations of hydrology and landsat data on sediment concentrations were combined to estimate rates of transport and the fate of water and sediment in a 200 km reach of the central amazon river results from field data collected during the annual flood in july 1986 indicate that sediment was transported to the flood plain at rates ranging from 3 to 5 t d 1 m 1 with percentage deposition 80 yielding vertical rates of 0 8 to 1 6 cm day comparable rates were calculated from geographic information system overlays of numerically simulated specific water discharge and land sat derived sediment concentrations rates for july 31 1977 include 4 to 18 t d 1 m 1 of transport onto the flood plain and an average of 64 deposition at vertical rates from 0 4 to 3 3 cm d a 1 m higher flow on august 2 1989 yielded on average higher rates of transport onto the flood plain 8 to 15 t d 1 m 1 but lower percentage 46 deposition implying vertical rates between 0 3 and 2 9 cm d

predicting the saturated hydraulic conductivity of sand and gravel using effective diameter and void ratio this paper assesses methods to predict the saturated hydraulic conductivity k of clean sand and gravel currently in engineering the most widely used predictive methods are those of hazen and t

weathering and global denudation a negative correlation between sediment yield and weathering history as measured by the chemical alteration cia of the suspended sediment is observed for many of the world s major rivers and other regions of denudation the weathering history is a first order control on the sediment yield of such areas termed equilibrium denudation regions for other areas data scatter with either apparent increases or decreases of sediment yield for given cia values these areas are termed nonequilibrium denudation regions low sediment yields can be attributed to moderated erosion either natural or human induced and or the incorporation of unweathered glacial debris accelerated erosion resulting in high sediment yield is primarily human induced and results from cultivation and other land use each of these effects has a profound influence on global sediment discharge from the continents pre human suspended sediment discharge from the continents is estimated to be 12 6 times 10 15 g yr or about 0 6 the

geomorphic tectonic control of sediment discharge to the ocean the importance of small mountainous rivers analysis of data from 280 rivers discharging to the ocean indicates that sediment loads yields are a log linear function of basin area and maximum elevation of the river basin other factors controlling sediment discharge e g climate runoff appear to have secondary importance a notable exception is the influence of human activity climate and geology on the rivers draining southern asia and oceania sediment fluxes from small mountainous rivers many of which discharge directly onto active margins e g western south and north america and most high standing oceanic islands have been greatly underestimated in previous global sediment budgets perhaps by as much as a factor of three in contrast sediment fluxes to the ocean from large rivers nearly all of which discharge onto passive margins or marginal seas have been overestimated as some of the sediment load is subaerially sequestered in subsiding deltas before the proliferation of dam construction in the latter half of this century rivers

development testing and applications of site specific tsunami inundation models for real time forecasting 1 the study describes the development testing and applications of site specific tsunami inundation models forecast models for use in noaa s tsunami forecast and warning system the model development process includes sensitivity studies of tsunami wave characteristics in the nearshore and inundation for a range of model grid setups resolutions and parameters to demonstrate the process four forecast models in hawaii at hilo kahului honolulu and nawiliwili are described the models were validated with fourteen historical tsunamis and compared with numerical results from reference inundation models of higher resolution the accuracy of the modeled maximum wave height is greater than 80 when the observation is greater than 0 5 m when the observation is below 0 5 m the error is less than 0 3 m the error of the modeled arrival time of the first peak is within 3 of the travel time the developed forecast models were further applied to hazard assessment from simulated magnitude 7 5 8 2 8 7 and 9 3 tsunamis based on subduction zone earthquakes in the pacific the tsunami hazard assessment study indicates that use of a seismic magnitude alone for a tsunami source assessment is inadequate to achieve such accuracy for tsunami amplitude forecasts the forecast models apply local bathymetric and topographic information and utilize dynamic boundary conditions from the tsunami source function database to provide site and event specific coastal predictions only by combining a deep ocean assessment and reporting of tsunami constrained tsunami magnitude with site specific high resolution models can the forecasts completely cover the evolution of earthquake generated tsunami waves generation deep ocean propagation and coastal inundation wavelet analysis of the tsunami waves suggests the coastal tsunami frequency responses at different sites are dominated by the local bathymetry yet they can be partially related to the locations of the tsunami sources the study also demonstrates the nonlinearity between offshore and nearshore maximum wave amplitudes

fluvial sediment delivery to a coastal plain estuary in the atlantic drainage of the united states abstract drastic changes in sediment production in drainage basins can have significant impacts on sediment yield to estuaries however significant but less spectacular changes in fluvial sediment regimes have not greatly influenced sediment output of some rivers in the united states atlantic drainage the limited influence of moderate or incremental changes in fluvial sediment systems on estuarine sediment delivery may be attributable to the large proportion of eroded sediment which is stored within the basins and the transport limited nature of long term sediment yields a sediment budget for the pee dee river basin and waccamaw river winyah bay estuary of the carolinas shows that only a small proportion of gross eroded sediment within the basin about 4 reaches the estuary on an average annual basis because the system appears to be transport limited it is estimated that an 88 reduction in the quantity of eroded sediment reaching streams would be necessary to produce significant change in sediment yield to the estuary any increase in sediment production would not be reflected at all in the estuary unless it was accompanied by a corresponding increase in fluvial sediment conveyance capacity estuarine sedimentary records thus may not reflect some significant changes in fluvial sediment systems

sediment transport due to extreme events the hudson river estuary after tropical storms irene and lee 1 tropical storms irene and lee in 2011 produced intense precipitation and flooding in the u s northeast including the hudson river watershed sediment input to the hudson river was approximately 2 7 megaton about 5 times the long term annual average rather than the common assumption that sediment is predominantly trapped in the estuary observations and model results indicate that approximately two thirds of the new sediment remained trapped in the tidal freshwater river more than 1 month after the storms and only about one fifth of the new sediment reached the saline estuary high sediment concentrations were observed in the estuary but the model results suggest that this was predominantly due to remobilization of bed sediment spatially localized deposits of new and remobilized sediment were consistent with longer term depositional records the results indicate that tidal rivers can intercept at least temporarily delivery of terrigenous sediment to the marine environment during major flow events

a chronology of natural and anthropogenic influences on coastal sedimentation new zealand 14c and 137cs chronologies of sediment accumulation were obtained from five sediment cores taken from wellington harbour new zealand a 10 000 year chronology records the holocene transgression european colonisation and variations in the general sediment accumulation rate caused by earthquake uplift and anthropogenic activity rates vary from a high of 60 to a low of 0 1 mm a 1 in general rates increased at the beginning of the holocene marine transgression but by 5000 yr bp they reached a stable level harbour wide these rates remained stable until the second half of the 19th century when deforestation by european settlers caused order of magnitude increases in sediment accumulation in the past 40 80 years rates have increased again as a result of urban growth and river channel management although the effects are less pervasive harbour wide influences can be placed in two categories natural and anthropogenic the latter being recent contributions to a sedimentary regime dominated by the holocene marine transgression sediment accumulation rates indicate that two major earthquake uplift events had only a local effect on harbour sediments anthropogenic influences are considered to be more significant sedimentologically than earthquake activity

estimating the in situ porosity of sandy soils sampled in boreholes abstract this paper deals with sandy aquifers it explains how to use parameters of borehole samples and data of mechanical tests performed in boreholes to assess the in situ values of porosity the concepts of maximum and minimum void ratios emax and emin are presented with the results of studies trying to predict their values predictive equations are proposed to link the values of emax and emin to that of the coefficient of uniformity cu of the grain size distribution curve and the roundness factor rf of solid particles once the values of emax and emin have been estimated those of the in situ void ratio e and porosity n can be assessed from the data of in situ mechanical tests for example split spoon tests an example evaluation is presented for an unconfined sand aquifer which was investigated using boreholes field tests laboratory tests slug tests in monitoring wells and a long term pumping test

erosion thresholds and suspended sediment yields waipaoa river basin new zealand characteristics of the suspended sediment load in the waipaoa river new zealand and in two of its tributaries mangatu and te arai rivers are examined for evidence of different dominant erosion processes in the basins upstream different shapes of the suspended sediment concentration water discharge relations lead to differences in long term average yield event yield magnitude frequency relations and relative importance of large flows and rare events in the mangatu river frequent runoff events 2 1 are relatively more important to the long term yield 11 540 t km yr half of the long term average load is transported by events with return periods less than 1 year and there is little evidence of an erosion threshold limitation on sediment supply this is consistent with the predominance in the mangatu basin of hillslope erosion processes that involve scour by surface and channelized runoff particularly gully erosion this contrasts with the te arai river where sediment concentration tends to be much lower at low and moderate flows frequent runoff events transport less of the long term yield 4600 t km 2 yr than do rarer large magnitude flood events event sediment yields are an order of magnitude lower during events with subannual return periods and half of the long term average load is transported during events with a return period of 2 years some of these characteristics appear to result in part from two populations of runoff events in the te arai basin nonetheless they are consistent with field evidence that most of the sediment supplied to the te arai stream network is generated by shallow landslides which are activated once a rainfall threshold is exceeded

runup of solitary waves on a circular island this is a study of the interactions of solitary waves climbing up a circular island a series of large scale laboratory experiments with waves of different incident height to depth ratios and different crest lengths is described detailed two dimensional run up height measurements and time histories of surface elevations around the island are presented a numerical model based on the two dimensional shallow water wave equations including runup calculations was developed numerical model predictions agreed very well with the laboratory data and the model was used to study wave trapping and the effect of slope under certain conditions enhanced runup and wave trapping on the lee side of the island were observed suggesting a possible explanation for the devastation reported by field surveys in babi island off flores indonesia and in okushiri island japan

carbon burial in soil sediments from holocene agricultural erosion central europe 1 natural and human induced erosion supplies high amounts of soil organic carbon oc to terrestrial drainage networks yet oc fluxes in rivers were considered in global budgets only recently modern estimates of annual carbon burial in inland river sediments of 0 6 gt c or 22 of c transferred from terrestrial ecosystems to river channels consider only lakes and reservoirs and disregard any long term carbon burial in hillslope or floodplain sediments here we present the first assessment of sediment bound oc storage in central europe from a synthesis of 1500 holocene hillslope and floodplain sedimentary archives we show that sediment storage increases with drainage basin size due to more extensive floodplains in larger river basins however hillslopes retain hitherto unrecognized high amounts of eroded soils at the scale of large river basins such that average agricultural erosion rates during the holocene would have been at least twice as high as reported previously this anthropogenic hillslope sediment storage exceeds floodplain storage in drainage basins 105 km2 challenging the notion that floodplains are the dominant sedimentary sinks in terms of carbon burial oc concentrations in floodplains exceed those on hillslopes and net oc accumulation rates in floodplains 0 7 0 2 g c m 2a 1 surpass those on hillslopes 0 4 0 1 g c m 2a 1 over the last 7500 years we conclude that carbon burial in floodplains and on hillslopes in central europe exceeds terrestrial carbon storage in lakes and reservoirs by at least 2 orders of magnitude and should thus be considered in continental carbon budgets

rivers in the anthropocene the u s perspective abstract during the past 50 yr the number and variety of papers written by u s fluvial geomorphologists that examine human alterations of rivers has accelerated substantially from an initial focus primarily on how human induced changes in land cover influence sediment yield and river dynamics the literature has expanded to emphasize the effects of flow regulation channel engineering removal of large wood and beavers and changing climate these multiple human influences are now widely recognized to have resulted in global scale cumulative effects including significantly altered fluxes of water sediment nitrogen and carbon and complete transformation of river networks across much of the planet one outgrowth of this recognition is the increasing involvement of geomorphologists in diverse forms of river restoration a form of river management that thus far has largely been dominated by engineers acknowledging the ubiquity of human alteration of rivers implies that i investigators cannot assume that even the most remote and seemingly pristine river segment has not been affected at least indirectly by people ii the use of reference conditions requires careful consideration with respect to what reference sites indicate about past conditions as well as their relevance for the future iii detailed geomorphic understanding of the nature and timing of past human alterations of rivers is likely to be critical to effective restoration and iv each scientist must decide how to engage within the context of research and advocacy with the issues of ecosystem degradation and loss of river form and function

changes in sediment yield of the yellow river basin of china during the holocene this research reconstructs the changes in sediment yield of the yellow river based mainly on a large number of 14 c dates collected from the literature the total volume of sediment yield of the basin during the holocene is estimated to be 8 0 x 10 12 tons the annual sediment yield had an increasing trend over the holocene from 0 68 0 72 0 79 to 1 0 1 x 10 9 tons over each 2500 year period from the early holocene to the present the changes in sediment yield are ascribed to both natural and anthropogenic reasons in which the latter became important in the late holocene the mean rate of increase in natural sediment yield throughout the holocene is estimated to be about 0 027 x 10 6 ton year and the natural annual sediment yield is projected to be 0 95 x 10 9 tons at the present the increasing trend of natural sediment yield is reasoned to be the consequence of evolution of landforms enhanced by tectonic movement and climatic change in the loess plateau the principal sediment source of the river towards a condition favorable to soil erosion comparing the estimated annual natural sediment yield with the current annual sediment load of 1 6 x 10 9 tons of the river it is clear that human activities have augmented natural soil erosion by about 41 in the yellow river basin furthermore an estimate of the overall pattern of anthropogenic sediment yield shows an accelerated increasing trend which is approximately correspondent with that of population in the loess plateau area c 2002 elsevier science b v all rights reserved

shock capturing boussinesq type model for nearshore wave processes this paper describes the formulation and validation of a nearshore wave model for tropical coastal environment the governing boussinesq type equations include the conservative form of the nonlinear shallow water equations for shock capturing a riemann solver supplies the inter cell flux and bathymetry source term while a godunov type scheme integrates the evolution variables in time the model handles wave breaking through momentum conservation with energy dissipation based on an eddy viscosity concept the computed results show very good agreement with laboratory data for wave propagation over a submerged bar wave breaking and runup on plane beaches as well as wave transformation over fringing reefs the model accurately describes transition between supercritical and subcritical flows as well as development of dispersive waves in the processes

land water boundary treatment for a tsunami model with dimensional splitting the method of splitting tsunamis most model adapted by national oceanic and atmospheric administration noaa for tsunami forecasting operations is praised for its computational efficiency associated with the use of splitting technique it will be shown however that splitting the computations between x and y directions results in specific sensitivity to the treatment of land water boundary slight modification to the reflective boundary condition in most caused an appreciable difference in the results this is demonstrated with simulations of the tohoku 2011 tsunami from the source earthquake to monterey bay california and in southeast alaska followed by comparison with tide gage records in the first case the better representation of later waves reflected from the coasts by the modified model in a pacific wide simulation resulted in twice as long match between simulated and observed tsunami time histories at monterey gage in the second case the modified model was able to propagate the tsunami wave and approach gage records at locations within narrow channels juneau ketchikan to where most had difficulty propagating the wave the modification was extended to include inundation computation the resulting inundation algorithm cliffs has been tested with the complete set of noaa recommended benchmark problems focused on inundation the solutions are compared to the most solutions obtained with the version of the most model benchmarked for the national tsunami hazard mitigation program in 2011 in two tests cliffs and most results are very close and in another two tests the results are somewhat different very different regimes of generation disposal of water by cliffs and most inundation algorithms which supposedly affected the benchmarking results have been discussed

recent lake sedimentation in the middle and lower yangtze basin inferred from 137 cs and 210 pb measurements abstract the reduction of water storage capacity in the lakes of the yangtze basin was an important factor for the disastrous 1998 flooding this study attempted to quantify sedimentation and its role in the water storage reduction in the middle and lower reaches of the yangtze basin using the radionuclide of caesium 137 137cs and lead 210 210pb as tracers sixteen cores were taken from eight lakes including the two largest lakes in the region poyanghu and dongtinghu the two dating techniques were used in combination to quantify recent sediment accumulation rates and their changes over the last few decades the 137cs and 210pb measurements indicated higher sedimentation rates for dongtinghu which were consistent with observed severe reduction of water storage capacity the inferred sedimentation rates for the remaining lakes were lower and did not reflect the perceived rate of severe soil erosion upstream or the substantial water storage reduction the low sedimentation rates inferred for most lakes tentatively suggest that sediment deposition was not the primary reason for the observed reduction in water storage capacity nevertheless a clear increasing trend in sedimentation rates has been documented for most of the studied lakes over the past few decades sedimentation and its role in water storage reduction require further study due to the many problems associated with its quantification such as the post depositional redistribution of sediments and water exchanges between the yangtze river and the studied lakes

sediment budgets for a sediment laden river the lower wei river in the period 1960 1990 fluvial sediment delivery is the main form of sediment transfer from the land to the sea but this process is currently undergoing significant variations due to the alteration of catchment and base level controls related to climate change and human activities especially the widespread construction of dams using the lower wei river as an example and an integrated approach this study investigates the variation of fluvial sediment delivery as well as the connectivity under the effects of both controls based on hydrological records and channel cross section surveys sediment budgets were constructed for two periods 1960 1970 1970 1990 after the dam was closed in 1960 in the period 1960 1969 due to the elevated base level 327 2 1 62m caused by the dam the aggradation rate was 0 451x10 8 tyr 1 in the channel and 0 716x10 8 tyr 1 on the floodplain indicating that the positive lateral connectivity between these locations was enhanced as a consequence serious sediment storage resulted in a sediment delivery ratio sdr that was smaller than that occurring before 1960 in the period 1970 1990 sweeping soil and water conservation swc measures were implemented resulting in a reduction of the connectivity between the trunk and tributaries and a decrease of similar to 31 in the mean sediment input in addition together with the base level fluctuation in the range of 327 47 0 49m the annual variation in sediment storage was primarily dependent on the water sediment regime affected by the swc the negative lateral connectivity was enhanced between the channel and floodplain via bank erosion consequently the aggradation rate was reduced by 89 on the floodplain and by 96 in the channel sediment output continued to decrease primarily due to the swc practices and climate changes in this period whereas the sdr increased due to the enhanced longitudinal connectivity between the upstream and downstream copyright c 2014 john wiley sons ltd

a pore size distribution function based method for estimation of hydraulic properties of sandy soils abstract hydraulic property of soil is key information required for understanding the groundwater flow in the soil including saturated and unsaturated zone the water flow in soil is governed by the geometrical pore space characteristics of soil structure i e pore size distribution function even though the concept of pore size distribution function had been proposed decades ago the pore size distribution function is rarely used to estimate the hydraulic properties in engineering practice in practice the effective particle size i e d10 and void ratio e are commonly used for the estimation of saturated coefficient of permeability ks for sandy soils neither d10 nor e can accurately represent the geometrical pore space in soil with the development of unsaturated soil mechanics it is observed that the pore size distribution function can be expressed in another form which is named as soil water characteristic curve swcc in this study the coefficients of permeability of sandy soils were estimated using the concept of pore size distribution function or swcc the comparison between the estimated results using the proposed equation and the measured data from laboratory tests in nanyang technological university ntu showed that the proposed equation in this note provided good estimation of ks

predicting the terrestrial flux of sediment to the global ocean a planetary perspective a new model for predicting the long term flux of sediment from river basins to the coastal ocean is applied to a global data set of 340 river basins the model is based on relief basin area or averaged discharge and basin averaged temperature basinaveraged temperature is determined from basin location latitude longitude and the lapse rate across the basin relief hypsometric approximation the sediment flux model incorporates climate through basin temperature and hydrologic runoff solutions are provided for each of the major hemispheric climate regions polar temperate and tropic the model successfully predicts the pre anthropogenic flux of sediment to within the uncertainties associated with the global observations within a factor of two for 75 of rivers that range across five orders of magnitude in basin area and discharge most of the problem rivers are associated with low observational loads often smaller rivers where anthropogenic impacts are often magnified and temporal variability is high model predictions provide a baseline for researchers 1 to question the quality of observational data where available and disagreement is greatest 2 to examine a river basin for unusually large anthropogenic influences i e causes of erosion or causes of hinterland sediment retention and 3 to uncover secondary factors not addressed by our model lithology lakes the model provides a powerful tool to address the impact of paleo climate fluctuations warmer colder wetter drier on the impact of sediment flux to the coastal ocean d 2003 elsevier b v all rights reserved

laboratory experiments of tsunami runup on a circular island laboratory experiments of a 7 2 m diameter conical island were conducted to study three dimensional tsunami runup the 62 5 cm tall island had 1 on 4 side slopes and was positioned in the center of a 30 m wide by 25 m long flat bottom basin solitary waves with height to depth ratios ranging from 0 05 to 0 20 and source lengths ranging from 0 30 to 7 14 island diameters were tested in water depths of 32 and 42 cm twenty seven capacitance wave gages were used to measure surface wave elevations at incident and four radial transects on the island slope maximum vertical runup measurements were made at 20 locations around the perimeter of the island using rod and transit a new runup gage was located on the back or lee side of the island to record runup time series

terrestrial sedimentation and the carbon cycle coupling weathering and erosion to carbon burial this paper examines the linkages between the carbon cycle and sedimentary processes on land available data suggest that sedimentation on land can bury vast quantities of organic carbon roughly 1015 g c yr 1 to evaluate the relative roles of various classes of processes in the burial of carbon on land terrestrial sedimentation was modeled as a series of 864 scenarios each scenario represents a unique choice of intensities for seven classes of processes and two different global wetland distributions comparison was made with presumed preagricultural conditions the classes of processes were divided into two major component parts clastic sedimentation of soil derived carbon and organic sedimentation of autochthonous carbon for clastic sedimentation masses of sediment were considered for burial as reservoir sediment lake sediment and combined colluvium alluvium and aeolian deposits when the ensemble of models is examined the human induced burial of 0 6 1 5 1015 g yr 1 of carbon on land is entirely plausible this sink reaches its maximum strength between 30 and 50 n paddy lands stand out as a type of land use that warrants future study but the many faces of rice agriculture limit generalization in an extreme scenario paddy lands alone could be made to bury about 1 1015 g c yr 1 arguing that terrestrial sedimentation processes could be much of the sink for the so called missing carbon is reasonable such a hypothesis however requires major redesign of how the carbon cycle is modeled unlike ecosystem processes that are amenable to satellite monitoring and parallel modeling many aspects of terrestrial sedimentation are hidden from space

the runup of solitary waves this is a study of the runup of solitary waves on plane beaches an approximate theory is presented for non breaking waves and an asymptotic result is derived for the maximum runup of solitary waves a series of laboratory experiments is described to support the theory it is shown that the linear theory predicts the maximum runup satisfactorily and that the nonlinear theory describes the climb of solitary waves equally well different runup regimes are found to exist for the runup of breaking and non breaking waves a breaking criterion is derived for determining whether a solitary wave will break as it climbs up a sloping beach and a different criterion is shown to apply for determining whether a wave will break during rundown these results are used to explain some of the existing empirical runup relationships

estuarine sedimentary response to atlantic tropical cyclones abstract in late summer 2011 hurricane irene and tropical storm lee impacted virtually every coastal river and estuary along the u s north atlantic seaboard we investigated the sedimentary response of the delaware estuary to these tropical cyclones through coordinated observations of flow and suspended sediment transport from moored instrumentation hydrographic surveys and sediment coring on 27 28 august hurricane irene tracked offshore of the estuary and generated strong northwesterly winds and intense short lived rainfall and river runoff on 7 8 september the remnants of tropical storm lee tracked inland along the drainage basin and produced weaker winds but more widely distributed and longer lived rainfall and river runoff an estimated 1 4 0 6 10 6 metric tons of fluvial suspended sediment was delivered to the estuary in association with these storms record setting freshwater discharges generated by lee displaced the salt front 50 km seaward of its pre storm position yet the front and associated estuarine turbidity maximum were not flushed beyond the mouth convergent gravitational and tidal circulations effectively trapped suspended sediment delivered to and produced within the estuary during the storm period normal conditions of estuarine circulation and sediment flux rebounded about five days after the passage of irene but did not fully recover before the approach of lee and it was not until two weeks thereafter that the estuary recovered bed sedimentology and inventories of the radionuclide 7 be t 1 2 53 days revealed that the upper estuary floor scoured in places under storm enhanced bottom currents whereas the lower estuary remained depositional throughout the storm period sediment flux and coring observations indicate that estuary bed resuspension was the main source of suspended sediment transported in the estuary during irene and was a major source during lee along with fluvial sediment delivered from the drainage basin regardless of the source our observations make clear that the estuary is capable of trapping suspended sediment and preventing its escape to the coastal ocean during extreme oceanic storms

an approximation of the sediment budget of the lower mississippi river prior to major human modification a sediment budget is constructed for the lower mississippi river prior to the introduction of most human modifications components of the budget are derived from historical data including mississippi river commission hydrographic survey maps for the period from 1877 to 1924 a quantitative estimate of major sediment sources sinks and storage locations in the lower mississippi valley suggest that the most important sediment source was from bank caving and that at least 50 per cent more sediment was deposited in short term channel storage than in longer term overbank storage the budget indicates that the proportion of sediment transported as bedload was significantly greater than previously estimated the magnitude and variability of these sediment budget components are discussed the results of the study suggest that prior to modifications the river was aggrading over much of its length

delivery of upper basin sediment to the lower neuse river north carolina u s a extensive storage of upper basin piedmont sediment and apparent low sediment supply to streams in lower basin coastal plain areas generates questions as to the source of alluvium in lower reaches of rivers of the u s atlantic drainage this was investigated on the neuse river north carolina using a mineralogical indicator of sediment source areas the utility of mica flakes for discriminating between piedmont and non piedmont sources of sediment in the lower coastal plain reaches of the neuse was established on the basis of an examination of the u s national soils database and of 26 soil surveys of the north carolina coastal plain from the neuse river estuary to 48 km upstream there are no mica flakes in floodplain soils or in river bank and channel shelf sediments mica flakes become more common upstream this suggests that a very small proportion of the sediment eroded in the piedmont portion of the watershed is delivered to the river mouth the small amounts which presumably do reach the lower coastal plain are so diluted by coastal plain derived alluvium that no piedmont origin can be discerned this demonstrates a dominantly coastal plain source and underscores the importance of storage and discontinuous transport in fluvial sediment systems more importantly results suggest that upper and lower basin sediment dynamics are not only non linearly related but may be virtually decoupled

event suspended sediment characteristics and the generation of hyperpycnal plumes at river mouths east coast continental margin north island new zealand abstract steepland rivers draining small coastal watersheds often have very high suspended sediment loads but the event characteristics of suspended sediment concentration and yield in this class of river is not well documented continuous monitoring at four sites in the waipaoa river basin new zealand demonstrates that during individual and composite events suspended sediment concentration versus water discharge relations typically show clockwise hysteresis and that event maximum concentration is poorly related to event peak discharge the signature of different erosion processes is also imprinted on the event yield magnitude frequency distributions gully dominated tributary basins produce relatively high yields at all frequencies reflecting greater sediment availability whereas in tributary basins where shallow landsliding is the dominant erosion process there is a steep increase in yields in relation to return period we estimate that flood discharges from the waipaoa river approach or exceed

sedimentary controls on modern sand grain coat formation abstract coated sand grains can influence reservoir quality evolution during sandstone diagenesis porosity can be reduced and fluid flow restricted where grain coats encroach into pore space conversely pore lining grain coats can restrict the growth of pore filling quartz cement in deeply buried sandstones and thus can result in unusually high porosity in deeply buried sandstones being able to predict the distribution of coated sand grains within petroleum reservoirs is thus important to help find good reservoir quality here we report a modern analogue study of 12 sediment cores from the anllons estuary galicia nw spain collected from a range of sub environments to help develop an understanding of the occurrence and distribution of coated grains the cores were described for grain size bioturbation and sedimentary structures and then sub sampled for electron and light microscopy laser granulometry and x ray diffraction analysis the anllons estuary is sand dominated with intertidal sand flats and saltmarsh environments at the margins there is a shallowing fining upwards trend in the estuary fill succession grain coats are present in nearly every sample analysed they are between 1 m and 100 m thick and typically lack internal organisation the extent of grain coat coverage can exceed 25 in some samples with coverage highest in the top 20 cm of cores samples from muddy intertidal flat and the muddy saltmarsh environments close to the margins of the estuary have the highest coat coverage mean coat coverage of 20 2 and 21 3 respectively the lowest mean coat coverage occurs in the sandy saltmarsh 10 4 beyond the upper tidal limit and sandy intertidal flat environments 8 4 close to the main estuary channel mean coat coverage correlates with the concentration of clay fraction the primary controls on the distribution of fine grained sediment and therefore grain coat distribution are primary sediment transport and deposition processes that concentrate the clay fraction in the sediment towards the margins of the estuary bioturbation and clay illuviation mechanical infiltration are secondary processes that may redistribute fine grained sediment and produce grain coats here we have shown that detrital grain coats are more likely in marginal environments of ancient estuary fills which are typically found in the fining upward part of progradational successions

goodbye hazen hello kozeny carman the century old hazen formula for predicting the permeability of sand is based only on the d10 particle size whereas the half century old kozeny carman formula is based on the entire particle size distribution the particle shape and the void ratio as a consequence the hazen formula is less accurate than the kozeny carman formula it is recommended that the former be retired and the latter be adopted

rates of continental erosion and mountain building the first objective of this work was to obtain values for the rates at which continental erosion can smooth out or remove the topographic expression produced by orogeny the dominant part is played by mechanical erosion which acts most strongly in regions of large topographic expression chemical erosion depends strongly on precipitation or runoff in individual river drainage basins but because most continents have very similar average rainfall chemical erosion is fairly uniform for continental sized areas and will succeed in planing down all continents to a level peneplain if given enough time the exception to this rule is australia which has a very low chemical erosion rate because of its dryness the time constants for mechanical and chemical erosion so obtained vary between about 30 and 300 my depending on the continent and the assumptions made mountain building occurs throughout the geological time scale but at a non uniform rate although there will not be a balance between erosion and mountain building over a short time scale due to the non uniform rate of mountain building the long term situation must be that the two phenomena should balance out it is shown that the freeboard of continents will respond to the long term balance between mountain building and erosion an expression has been derived for the average continental elevation in which the rate of mountain building depends on the rate of radiogenic heat production within the earth it is shown that relatively small changes in average elevation above sea level of a few hundred metres are predicted to have occurred since the beginning of the proterozoic as mountain building is predicted to decrease on average with time because of the reduction in internal heat generation and as erosion is dependent on the average elevation this average elevation will decrease slowly through time the opposite of what some workers have predicted a more complicated model of mountain building is then investigated in which one component of mountain building has a sinusoidal signal the oscillations in average elevation depend on the period of the sinusoid being smaller for shorter periods finally an average continental elevation is derived using a list of real orogenic events although this list of orogenies is incomplete there is some indication that the actual continental elevation as seen in the flooding history of the continents is similar to that derived in this paper

sediment load trends in the magdalena river basin 1980 2010 anthropogenic and climate induced causes abstract the colombian andes and its main river basin the magdalena have witnessed dramatic changes in land cover and further forest loss during the last three decades for the magdalena river human activities appear to have played a more prominent role compared to rainfall climate change to mobilize sediment however environmental authorities in colombia argue that climate change is the main trigger of erosion and floods experienced during the last decade here we present the first regional exercise addressing the following 1 what are the observed trends of sediment load in the northern andes during the last three decades and 2 are sediment load trends in agreement with tendencies in land use change and climate e g precipitation we perform mann kendall tests on sediment load series for 21 main tributary systems during the 1980 2010 period these gauging stations represent 77 of the whole magdalena basin area the last decade has been a period of increased pulses in sediment transport as seen by the statistical significant trends in load overall six subcatchments representing 55 of the analyzed magdalena basin area have witnessed increasing trends in sediment load also some major tributaries have experienced changes in their interannual mean sediment flux during the mid 1990s and 2005 further analysis of land cover change e g deforestation indicates that the basin has undergone considerable change forest cover decreased by 40 over the period of study while the area under agriculture and pasture cover agricultural lands 1 and 2 increased by 65 the highest peak of forest loss on record in the magdalena basin 5106 km2 or 24 of the combined deforestation in colombia occurred during the 2005 2010 period in contrast mann kendall tests on rainfall series for 61 stations reveal that precipitation shows no regional signs of increasing trends also increasing trends in sediment load match quite well with the marked increase in forest clearance during the 1990 2000 and 2005 2010 periods such signs of increasing sediment fluxes should not be attributed to climate change and rainfall variability alone as a whole the magdalena one of the top 10 rivers in terms of sediment delivery to the ocean 184 mt y 1 and its tributaries have experienced increasing trends in sediment load during the 1980 2010 period increases in close agreement with trends in land use change and deforestation during the last decade the magdalena river drainage basin has witnessed an increase in erosion rates of 34 from 550 t km 2 y 1 before 2000 to 710 t km 2 y 1 for the 2000 2010 period and the average sediment load for the whole basin increased to 44 mt y 1 for the same period similar to the global picture of human contribution to sediment generation the rate of anthropogenic soil erosion in the magdalena basin probably exceeds the rate of climate driven erosion by several orders of magnitude

sediment deposition and erosion during the extreme flood events in the middle and lower reaches of the yangtze river abstract floods often are accompanied by intensified soil erosion and thus high sediment supply from the catchment into the main channel of the river this paper examined the sediment processes especially deposition and erosion during the two extreme flood years in 1954 and 1998 in the middle and low reaches of the yangtze river the total amount of sediment supplied to the middle and lower reaches from yichang hankou and hankou datong was 1095 mt in 1954 and 855 9 mt in 1998 or 176 and 137 of the averaged 622 mt a from 1950 to 2006 a high deposition occurred in the floodplains lakes and channels along the section yichang hankou both in 1954 and 1998 the total deposition reached 635 mt and 499 mt in 1954 and 1998 or 138 and 124 of the sediment load measured at the datong station respectively however different processes in the downstream section hankou datong during the two flood events were found severe erosion 140 mt happened in 1954 but only a slight erosion occurred 22 mt in 1998 thus the floodplains and channels in the middle and lower reaches of the yangtze river play an important role in regulating sediment discharge during extreme flood events the heavy deposition in the middle reaches effectively reduced the amount of sediment discharged into the river mouth and thus acted as a major depocenter in the extreme flood year the results also suggested that the yichang hankou tended to shift from a depositional section to an erosional section whereas the hankou datong changed from an erosion dominated section to a deposition dominated section even before the three gorges reservoir infilling in 2003 it is anticipated that this tendency would be accelerated and the historical role of sediment regulation by the two reaches could eventually be changed due to the reduced sediment supply from the upper yangtze

estimating ancient sediment fluxes original phanerozoic sediment flux rates can be approximated by fitting an exponential decay curve to the observed massjage distribution of sediments then multiplying the ratio of the observed mass to the exponential decay curve mass by the zero age flux rate predicted by the exponential decay curve applied to the massjage distribution of existing phanerozoic sediments the reconstruction method indicates that original global sediment flux rates varied cyclically by a factor of up to three this implies significant changes in the rates of uplift and mountain building and global plate tectonic activity

direct energy estimation of the 2011 japan tsunami using deep ocean pressure measurements 1 we have developed a method to compute the total energy transmitted by tsunami waves to the case where the earthquake source is unknown by using deep ocean pressure measurements and numerical models tsunami source functions based on the first wave recorded at the two closest tsunameters deep ocean assessment and reporting of tsunamis dart our analysis suggests that the march 11 2011 tohoku oki tsunami generated off japan originated from a 300 400 km long and 100 km wide area and the total propagated energy is 3 1015j with 6 uncertainty measurements from 30 tsunameters and 32 coastal tide stations show excellent agreement with the forecasts obtained in real time our study indicates that the propagated energy and the source location are the most important source characteristics for predicting tsunami impacts interactions of tsunami waves with seafloor topography delay and redirect the energy flux posing hazards from delayed and amplified waves with long duration seafloor topography also gives its spectral imprint to tsunami waves travel time forecast errors are path specific and correlated to the major wave scatterers in the pacific numerical dissipation in the propagation modeling highlights the need of high resolution inundation models for accurate coastal predictions on the other hand it also can be used to account for physical dissipation to achieve efficiency our results provide guidelines for the earliest reliable tsunami forecast warnings of long duration tsunami waves signals and enhancement of the experimental tsunami forecast system we apply the method to quantify the energy of 15 past tsunamis independently from earthquake magnitudes the small tsunami to seismic radiation energy ratios and their variability 0 01 0 8 reinforce the importance of using deep ocean tsunami data the direct measures of tsunamis for estimates of tsunami energy and accurate forecasting

on the use of the kozeny carman equation to predict the hydraulic conductivity of soils the saturated hydraulic conductivity of a soil can be predicted using empirical relationships capillary models statistical models and hydraulic radius theories a well known relationship between permeability and the properties of pores was proposed by kozeny and later modified by carman the resulting equation is largely known as the kozeny carman kc equation although the two authors never published together in the geotechnical literature there is a large consensus that the kc equation applies to sands but not to clays this view however is supported only by partial demonstration this paper evaluates the background and the validity of the kc equation using laboratory permeability tests test results were taken from publications that provided all of the information needed to make a prediction void ratio and either the measured specific surface for cohesive soils or the gradation curve for noncohesive soils the paper shows how to estimate the specific surface of a noncohesive soil from its g