improving understanding of near term barrier island evolution through multi decadal assessment of morphologic change abstract observed morphodynamic changes over multiple decades were coupled with storm driven run up characteristics at fire island new york to explore the influence of wave processes relative to the impacts of other coastal change drivers on the near term evolution of the barrier island historical topography was generated from digital stereo photogrammetry and compared with more recent lidar surveys to quantify near term decadal morphodynamic changes to the beach and primary dune system between the years 1969 1999 and 2009 notably increased profile volumes were observed along the entirety of the island in 1999 and likely provide the eolian source for the steady dune crest progradation observed over the relatively quiescent decade that followed persistent patterns of erosion and accretion over 10 30 and 40 year intervals are attributable to variations in island morphology human activity and variations in offshore bathymetry and island orientation that influence the wave energy reaching the coast areas of documented long term historical inlet formation and extensive bayside marsh development show substantial landward translation of the dune beach profile over the near term period of this study correlations among areas predicted to overwash observed elevation changes of the dune crestline and observed instances of overwash in undeveloped segments of the barrier island verify that overwash locations can be accurately predicted in undeveloped segments of coast in fact an assessment of 2012 aerial imagery collected after hurricane sandy confirms that overwash occurred at the majority of near term locations persistently predicted to overwash in addition to the storm wave climate factors related to variations within the geologic framework which in turn influence island orientation offshore slope and sediment supply impact island behavior on near term timescales

geomorphic and stratigraphic analysis of fire island new york abstract barrier islands along the east coast of the united states are believed to be migrating landward in response to sea level rise modes and rates of displacement of fire island along the south shore of long island n y were investigated through geomorphic and stratigraphic analyses inlet processes are principally responsible for bayshore sediment accretion and hence landward displacement while overwash has contributed to increasing the island s elevation portions of marsh areas covered by washover deposits were often raised above the tidal level permitting colonization by barrier flat vegetation photographic analysis showed that only the 1938 hurricane resulted in bayshore accretion by washover a small amount at one locality most of the bayside marshes formed on relict flood tidal delta shoals former inlet sites are characterized by typical geomorphic features including relict inlet ridges indentation of the bay shoreline wide marsh plains and relict flood tidal delta islands in the bay historical records and relict inlet features indicate that as much as 85 of the area has been affected by inlet activity the geomorphic and vegetative data supported by the stratigraphic interpretations showed that the western section of fire island n y is migrating landward more slowly than the eastern section of the barrier chain this trend is probably due to hurricane tracks and to an increased sediment supply to the western part barrier migration is occurring continuously over geologic time but considered on a short term basis displacement is sporadic and related to inlet processes over the past 1000 years fire island has experienced shoreface erosion as well as bayshore erosion and submergence

a mathematical model of spit growth and barrier elongation application to fire island inlet usa and badreveln spit sweden a mathematical model of spit growth and barrier elongation adjacent to an inlet of arbitrary width supplied by sediment coming from longshore sediment transport was developed based on the spit growth model proposed by kraus 1999 the fundamental governing equation is the conservation equation for sand where the width of the spit is assumed constant during growth the portion of the longshore sediment transport feeding the spit has been estimated based on the ratio between the depth of the inlet channel and the depth of active longshore transport sediment transport from the channel due to the inlet flow as well as other sinks of sand e g dredging are taken into account measured data on spit elongation at fire island inlet united states and at badreveln spit sweden were used to validate the model the simulated results agree well with the measured data at both study sites where spit growth at fire island was restricted by the inlet flow and the growth at badreveln spit was unrestricted the model calculation for fire island inlet indicates that the dredging to maintain channel navigation is the major reason for the stable period observed from 1954 to 1994 at the fire island barrier the average annual net longshore transport rate at the eastern side of the fire island inlet obtained in this study was about 220 000 m 3 yr of which approximately 165 000 m 3 yr 75 of the net longshore transport is deposited in the inlet feeding the spit growth whereas the remaining portion 25 is bypassed downdrift through the ebb shoal complex c 2011 elsevier ltd all rights reserved less

accelerated relative sea level rise and rapid coastal erosion testing a causal relationship for the louisiana barrier islands abstract the role of relative sea level rise as a cause for the rapid erosion of louisiana s barrier island coast is investigated through a numerical implementation of a modified bruun rule that accounts for the low percentage of sand sized sediment in the eroding louisiana shoreface shore normal profiles from 150 km of coastline west of the mississippi delta are derived from bathymetric surveys conducted during the 1880s 1930s and 1980s an rms difference criterion is employed to test whether an equilibrium profile form is maintained between survey years only about half the studied profiles meet the equilibrium criterion this represents a significant limitation on the potential applicability of the bruun rule the profiles meeting the equilibrium criterion along with measured rates of relative sea level rise are used to hindcast shoreline retreat rates at 37 locations within the study area modeled and observed shoreline retreat rates show no significant correlation thus in terms of the bruun approach relative sea level rise has no power for hindcasting and presumably forecasting rates of coastal erosion for the louisiana barrier islands

self potential variations with time and their relation to hydrogeologic and meteorological parameters a systematic investigation of self potentials sp shows that they vary considerably with time to study the influencing parameters repeated measurements were conducted every 14 days over a period of a year and a half along fixed profiles which extended over different lithological units an analysis of the recorded sp suggests decomposition into three components of different wavelengths variations of the sp with wavelengths in the 0 1 1 m range and amplitudes of up to 150 mv are thought to be induced by vegetation the mean amplitudes change with a one year period and there is a rough correlation with the soil temperature a long wavelength component wavelengths meters and some tens of meters amplitudes some 10 mv is attributed to changes of the underground lithology the long wavelength sp and its pronounced variation with time are assumed to be caused by water movements in layers of different permeability a morphology dependent trend of the sp values which has been much disputed in the literatu

streaming potential measurements 1 properties of the electrical double layer from crushed rock samples the potential has been inferred from streaming potential measurements with crushed rock samples as a function of ph and electrolyte concentration for various salts the value obtained for crushed fontainebleau sandstone at ph 5 7 and a kcl solution with a resistivity of 400 m is 40 5 mv where the error is dominated by sample to sample variations the sensitivity of the potential to the electrolyte resistivity for kcl is given experimentally by f 0 23 0 014 where f is the electrolyte resistivity the point of zero charge pzc is observed for ph 2 5 0 1 and the potential is positive for ph pzc for ph 5 the variations of the potential with ph can be approximated by ph 5 7 1 0 068 0 004 ph 5 7 for f 100 m the potential has been observed to be sensitive to the valence of the ions and is approximately reduced by the charge of the cation unless specific adsorption takes place like in the case of al 3 the experimental results are well accounted for by a three layer numerical model of the electrical double layer and the parameters of this model can be evaluated from the experimental data the sensitivity of the potential to the rock minerals has also been studied the potential obtained for granitic rocks is comparable to that obtained for fontainebleau sandstone but can be reduced by a factor of 2 4 for sandstones containing significant fractions of carbonates or clay to take into account the effect of the chemical composition of the electrolyte a chemical efficiency is defined as the ratio of the potential to the potential measured for kcl this chemical efficiency is measured to be 80 for typical groundwater but can be as low as 40 for a water with a high dissolved carbonate content the set of empirical laws derived from our measurements can be used to assess the magnitude of the streaming potentials expected in natural geophysical systems

sediment management at sandy hook nj an interaction of science and public policy abstract a century of human manipulation of sediment transport and sediment supply at sandy hook spit has generated an evolving suite of geomorphological responses and shoreline management approaches at this public coastal resource eventually a major erosion problem was created in a portion of the gateway national recreation area knows as the critical zone a location immediately downdrift of the end of a lengthy seawall in the last three decades the management approach was to apply beach nourishment to replace the eroded volumes projects emplacing from 20 000 m 3 to 1 7 million m 3 of sand in the critical zone attempted to counter the erosional trend however evolving park policy sought to identify alternatives to the massive emplacements of sand from offshore sources starting in 1997 detailed topographical surveys were begun to track sediment budget in the eroding critical zone and subsequently at gunnison beach a site of sediment accumulation a new management philosophy of smaller scale restoration of sediment supply in the critical zone has emerged at present the gunnison beach area on sandy hook is being monitored to determine its potential for sediment backpassing to the critical zone as a means to balance its local sediment budget create a relatively consistent topography and maintain the recreational resources

protecting natural landforms and habitats by nourishing an eroding estuarine beach an important issue facing coastal managers is how natural coastal habitats can be protected against wave erosion by human action an assessment is made of attempts to protect a rare maritime forest on the bay side of a barrier island at fire island new york usa using artificial beach fill the sediment deficit is caused by human attempts to stabilize the island by restricting inlet formation overwash and dune migration and it is exacerbated by a nearby marina bulkhead a total of 1099 m3 of sand dredged from the navigation channel was placed near the bulkhead loss of fill was 5 54 7 87 m3 m 1 in the first 6 months the fill was gone 18 months after placement sediment moving out of the fill area caused almost 4 m of shoreline advance 40 m downdrift after 6 months gain of 3 28 m3 m 1 followed by retreat of about 5 m at that location over the next 12 months loss of 5 51 m3 m 1 these results reveal how small changes in volume of microtidal estuarine beaches can cause great shoreline displacement rates the amount of fill from maintenance dredging is insufficient to replenish erosion losses placing additional fill sediment on the bayside to create artificial washover fans can mimic natural landforms and overcome loss of sediment inputs caused by stabilizing the ocean shore mechanical placement may be preferable to natural processes which would deliver sediment across the island and through pre existing stable habitat eliminating some of the features that take long to form

new empirical relationships among magnitude rupture length rupture width rupture area and surface displacement source parameters for historical earthquakes worldwide are compiled to develop a series of empirical relationships among moment magnitude m surface rupture length subsurface rupture length downdip rupture width rupture area and maximum and average displacement per event the resulting data base is a significant update of previous compilations and includes the additional source parameters of seismic moment moment magnitude subsurface rupture length downdip rupture width and average surface displacement each source parameter is classified as reliable or unreliable based on our evaluation of the accuracy of individual values only the reliable source parameters are used in the final analyses in comparing source parameters we note the following trends 1 generally the length of rupture at the surface is equal to 75 of the subsurface rupture length however the ratio of surface rupture length to subsurface rupture length increases with magnitude 2 the average surface displacement per event is about one half the maximum surface displacement per event and 3 the average subsurface displacement on the fault plane is less than the maximum surface displacement but more than the average surface displacement thus for most earthquakes in this data base slip on the fault plane at seismogenic depths is manifested by similar displacements at the surface log linear regressions between earthquake magnitude and surface rupture length subsurface rupture length and rupture area are especially well correlated showing standard deviations of 0 25 to 0 35 magnitude units most relationships are not statistically different at a 95 significance level as a function of the style of faulting thus we consider the regressions for all slip types to be appropriate for most applications regressions between magnitude and displacement magnitude and rupture width and between displacement and rupture length are less well correlated and have larger standard deviation than regressions between magnitude and length or area the large number of data points in most of these regressions and their statistical stability suggest that they are unlikely to change significantly in response to additional data separating the data according to extensional and compressional tectonic environments neither provides statistically different results nor improves the statistical significance of the regressions regressions for cases in which earthquake magnitude is either the independent or the dependent parameter can be used to estimate maximum earthquake magnitudes both for surface faults and for subsurface seismic sources such as blind faults and to estimate the expected surface displacement along a fault for a given size earthquake

low energy sandy beaches in marine and estuarine environments a review this review was undertaken to identify locations where low energy beaches may occur and their diagnostic forms and process controls including waves tides and water levels examples are drawn from the sheltered coastline of western australia near perth and fetch limited estuarine environments on the northeast coast of the united states we suggest that the term low energy be used in locations where 1 non storm significant wave heights are minimal e g 0 25 m 2 significant wave heights during strong onshore winds are low e g 0 50 m 3 beachface widths are narrow e g 20 m in microtidal environments and 4 morphologic features include those inherited from higher energy events micro topographic features can persist in the swash zone of low energy beaches under non storm wave conditions there is little evidence of cyclic cross shore sediment exchange bars excepting transverse forms located seaward of low still water level do not appear to be part of the sediment exchange system with the foreshore developing a better definition of the term low energy requires understanding the occurrence and duration of morphological characteristics and the type magnitude and frequency of hydrodynamic controls that are responsible for these characteristics efforts also should be directed toward 1 discriminating between processes generated within basins in true fetch limited environments and processes generated outside basins that affect sheltered environments 2 identifying the relative contributions of tide and surge related water level fluctuations on low energy beach shape and 3 estimating thresholds for beach change

the summit hydrothermal system of stromboli new insights from self potential temperature co2 and fumarolic fluid measurements with structural and monitoring implications accurate and precisely located self potential sp temperature t and co2 measurements were carried out in the summit area of stromboli along 72 straight profiles sp data were acquired every metre and t data every 2 5 m co2 concentrations were acquired with the same density as t but only along seven profiles the high density of data and the diversity of the measured parameters allows us to study structures and phenomena at a scale rarely investigated the shallow summit hydrothermal activity pizzo fossa area is indicated by large positive sp t and co2 anomalies these anomalies are focused on crater faults suggesting that the fracture zones are more permeable than surrounding rocks at stromboli the analysis of the distribution of these linear anomalies coupled with the examination of the geologic photographic and topographic data has led us to propose a new structural interpretation of the summit of stromboli this newly defined structural framework comprises 1 a large pizzo circular crater about 350 m in diameter 2 a complex of two concealed craters nested within the pizzo crater the large and the small fossa craters thought to have formed during the eruption of the pizzo pyroclastites unit the small fossa crater is filled with highly impermeable material that totally impedes the upward flow of hydrothermal fluids and 3 the present complex of active craters on the floor of the fossa short wavelength sp lows are organized in drainage like networks diverging from the main thermal anomalies and converging toward the topographic low in the fossa area inside the small fossa crater they are interpreted as the subsurface downhill flow of water condensed above the thermal anomalies we suspect that water accumulates below the small fossa crater as a perched water body representing a high threat of strong phreatic and phreatomagmatic paroxysms t and co2 anomalies are highly correlated the two types of anomalies have very similar shapes but the sensitivity of co2 measurements seems higher for lowest hydrothermal flux above t anomalies a pronounced high frequency sp signal is observed isotopic analyses of the fluids show similar compositions between the gases rising through the faults of the pizzo and large fossa craters this suggests a common origin for gases emerging along different structural paths within the summit of stromboli a site was found along the large fossa crater fault where high gas flux and low air contamination made gas monitoring possible near the active vents using the alkaline bottle sampling technique

change in morphology and modern sediment thickness on the inner continental shelf offshore of fire island new york between 2011 and 2014 analysis of hurricane impact abstract seafloor mapping investigations conducted on the lower shoreface and inner continental shelf offshore of fire island new york in 2011 and 2014 the period encompassing the impacts of hurricanes irene and sandy provide an unprecedented perspective regarding regional inner continental shelf sediment dynamics during large storm events analyses of these studies demonstrate that storm induced erosion and sediment transport occurred throughout the study area in water depths up to 30 m acoustic backscatter patterns were observed to move from 1 m to 450 m with a mean of 20 m and movement tended to decrease with increasing water depth these patterns indicate that both of the primary inner continental shelf sedimentary features in the study area linear sorted bedforms offshore of eastern fire island and shoreface attached sand ridges offshore of central and western fire island migrated alongshore to the southwest the migration of the sorted bedforms represents the modification of an active ravinement surface and is thought to have liberated a significant volume of sediment comparison of isopach maps of sediment thickness show that the volume of modern sediment composing the lower shoreface and shoreface attached sand ridges decreased by 2 8 10 6 m 3 across the 73 km 2 of common seafloor mapped in both surveys however a similar analysis for the relatively calmer 15 yr period prior to 2011 revealed significant accretion this allows speculation that the shoreface attached sand ridges are maintained over decadal timescales via sediment supplied through erosion of pleistocene outwash and lower holocene transgressive channel fill deposits exposed on the inner continental shelf but that the sand ridges also periodically erode and move to the southwest during large storm events analyses show that significant storm induced erosion and sediment transport occurs far seaward of the 5 to 9 m depth of closure assumed for fire island where it is thought that an onshore directed sediment flux from the inner continental shelf to the littoral system is required to balance the coastal sediment budget it is also thought that the morphology of the shoreface attached sand ridges controls the persistent shape of the adjacent shoreline through modification of incident waves thus we suggest that the sediment dynamics of the inner continental shelf and both storm induced and anthropogenic modification of the field of shoreface attached sand ridges be considered in future coastal resiliency planning

restoring sediment to compensate for human induced erosion of an estuarine shore abstract shoreline erosion is often exacerbated by reduction of sediment inputs because of interference with sediment transport by human structures we evaluate use of sediment dredged from a navigation channel to establish a feeder beach adjacent to a bulkhead as a solution for addressing erosion of landforms and habitats on sandy estuarine shores the objectives are to determine how beach volume position and shape within and downdrift of the fill area change and whether the volumes supplied by dredging match sediment losses caused by human actions the fill was placed along a 75 m length of shoreline adjacent to a marina in great south bay at fire island new york usa changes in beach shape and volume were determined from topographic surveys conducted before and after fill and at half year intervals for 18 months the quantity of fill was 1747 m3 maximum shoreline advance due to fill emplacement was 20 7 m the maximum volume placed at any transect was 28 6 m3 m 1 of shoreline length erosion of the fill occurred rapidly with landward migration of a conspicuous scarp the edge of the upland 18 months after the fill was placed was up to 4 6 m farther landward than prior to the fill movement of sediment alongshore downdrift of the fill occurred as wave like pulses extending the active foreshore bayward causing accretion of the inner low tide terrace burying saltmarsh peat outcrops on the foreshore and creating a higher and wider overwash platform over portions of the saltmarshes landforms downdrift of the fill area underwent successive stages including erosion pre nourishment accretion stability with throughput of sediment and then erosion beach nourishment compensates for human induced sediment losses the volume of sediment added from maintenance dredging can slow the rate of erosion but may not prevent long term shoreline retreat restoration and maintenance of coastal landforms and habitats to specific target states at a given location is difficult but augmenting longshore sediment inputs can allow those locations to undergo cycles of erosion and accretion creating a variety of landforms and habitats where only erosional forms existed previously alternatively nourishment could occur more frequently and in smaller volumes to reduce fluctuations in accretion erosion cycles

four year performance and associated controlling factors of several beach nourishment projects along three adjacent barrier islands west central florida usa abstract to quantify the performance of several beach nourishment projects on three adjacent barrier islands located in west central florida a total of 5200 beach and nearshore profiles spaced at 300 m were surveyed monthly to bi monthly from 2006 to 2010 beach nourishment performance at annual temporal and kilometer spatial scales within the microtidal low wave energy barrier island coast is most significantly influenced by the interruption of longshore sediment transport by complex tidal inlet processes the inlet processes directly influencing adjacent beach nourishment performance include longshore transport interruption resulting from divergence induced by wave refraction over an ebb tidal shoal flood tidal currents along the beach and total littoral blockage by structured inlets secondary factors controlling the nourishment performance include project length and width shoreline orientation and antecedent geology a morphologic indicator of a large longshore transport gradient within the study area is the absence of a nearshore sandbar these non barred beaches are characterized by persistent shoreline erosion the presence of a sandbar indicates the dominance of cross shore processes with bar migration in response to wave condition variations and a relatively stable shoreline the entirety of a barrier island system should be considered when evaluating the performance of a nourishment

burrowing inhibition by fine textured beach fill implications for recovery of beach ecosystems abstract beach nourishment is often considered the most environmentally sound method of maintaining eroding shorelines however the ecological consequences are poorly understood fill activities cause intense disturbance and high mortality and have the potential to alter the diversity abundance and distribution of intertidal macroinvertebrates for months to years ecological recovery following fill activities depends on successful recolonization and recruitment of the entire sandy intertidal community the use of incompatible sediments as fill material can strongly affect ecosystem recovery we hypothesized that burrowing inhibition of intertidal animals by incompatible fine fill sediments contributes to ecological impacts and limits recovery in beach ecosystems we experimentally investigated the influence of intertidal zone and burrowing mode on responses of beach invertebrates to altered sediment texture 28 38 fines and ultimately the potential for colonization and recovery of beaches disturbed by beach filling using experimental trials in fill material and natural beach sand we found that the mismatched fine fill sediments significantly inhibited burrowing of characteristic species from all intertidal zones including sand crabs clams polychaetes isopods and talitrid amphipods burrowing performance of all five species we tested was consistently reduced in the fill material and burrowing was completely inhibited for several species the threshold for burrowing inhibition by fine sediment content in middle and lower beach macroinvertebrates varied by species with highest sensitivity for the polychaete 4 fines below the usa regulatory limit of 10 fines followed by sand crabs and clams 20 fines these results suggest broader investigation of thresholds for burrowing inhibition in fine fill material is needed for beach animals burrowing inhibition caused by mismatched fill sediments exposes beach macroinvertebrates to stresses which could depress recruitment and survival at all intertidal zones our results suggest use of incompatible fine fill sediments from dredging projects creates unsuitable intertidal habitat that excludes burrowing macroinvertebrates and could delay beach ecosystem recovery through effects on beach invertebrates that are prey for shorebirds and fish the ecological impacts of filling with mismatched fine sediments could influence higher trophic levels and extend beyond the beach itself

origin evolution and distribution of shoreface sand ridges atlantic inner shelf u s a abstract a computer mapping system was employed to document the location of 259 shoreface attached and detached sand ridges in water although shoreface attached sand ridges appear to have several different modes of formation a two step process for the development of most shoreface attached and detached sand ridges along u s atlantic barrier island and cape coastlines is proposed 1 sand is deposited as ebb tidal deltas or river deltas along the lower shoreface and or inner continental shelf prior to or during transgression followed by 2 further transgression which reworks the deltaic sand bodies into linear sand ridges at the base of the shoreface by shelf processes the best developed shoreface sand ridge fields along the u s atlantic shelf lie adjacent to shorelines characterized by all of the following 1 transgression 2 mixed energy wave dominated barrier islands and 3 laterally migrating tidal inlet systems tidal inlet systems are natural sediment sinks that capture sand carried by longshore sediment transport ebb tidal delta deposits associated with these migrating tidal inlets provide the initial sand body for the development of shoreface attached sand ridges the oblique orientation and linear form of shoreface attached sand ridges appear to be a function of shoreline transgression lateral inlet migration and wave reworking of ebb tidal delta deposits concentrated along an ebb tidal delta retreat path shelf processes act as modifying agents in the evolution of sand ridges during and after ebb tidal delta deposition in general shoreface attached sand ridges are poorly developed or absent along eroding headlands spits and barrier island shorelines characterized by naturally stabilized tidal inlets these latter inlets and shoreline types are dominated or influenced by one or all of the following 1 antecedent topography 2 higher tidal ranges 3 larger tidal prisms 4 lower wave energies or 5 finer grain sizes the coupling of shoreline and shallow marine sedimentary processes during a transgression is critical to the origin evolution and distribution of shoreface sand ridges in the study area modern shoreface attached sand ridges are also known to occur in different coastal and shelf settings where large amounts of sediment were supplied to the shoreface and inner shelf during or immediately before transgression commonly observed vertical and lateral interrelationships of holocene shoreface attached sand ridges and tidal inlets or distributary channels have important ramifications for the development of shelf sandstone facies models in addition the geometric relationship documented in this study provides predictive petroleum and hard mineral exploration models of the spatial and temporal distribution of shoreface and shelf sand ridges

electrokinetic spontaneous polarization in porous media petrophysics and numerical modelling abstract the behaviour of streaming potential is directly related to movement of groundwater the responses for typical subsurface flows are modelled to investigate possibilities of spontaneous polarization sp when performing quantitative data interpretation the physical properties of geomaterials related to streaming potential are described a magnitude range of streaming current coefficient is assessed for geomaterials and found to be from 10 10 to 10 8 a pa m depending on water salinity and rock composition the electrical sources of sp caused by groundwater flow in saturated media are theoretically described it is shown that sp is completely defined by three types of electrical sources situated 1 on boundaries where water enters or quits porous media 2 in areas with transient regime and 3 on the boundaries of rocks with different properties hydraulic conductivity streaming current coefficients and electrical conductivity a 2d computer program based on the method of finite difference was created to provide numerical successive modelling of both groundwater flow and sp using sill s geophysics 48 1983 76 approach first the water heads are calculated then electrical sources of sp are obtained on the basis of the calculated heads and coefficient of streaming current finally the sp is obtained on the basis of calculated electrical sources and subsurface electrical conductivity numerical examples illustrating sp responses of infiltration of barrage with different electrical conductivity and of well pumping are discussed field data obtained at the site containing the dam between superficial artificial reservoir and the river are interpreted on the basis of numerical modelling the discussed method can be mainly used for additional calibration of groundwater flow models

self potential monitoring for hydrologic investigations in urban covered karst terrain abstractin the covered karst of west central florida usa sinkholes sandy collapse conduits provide locally concentrated recharge to underlying aquifers for water management it would be beneficial to understand the rates at which collapse conduits recharge an underlying aquifer self potential sp monitoring has promise as a noninvasive relatively low cost method for assessing temporal variability in flow previous studies suggested that negative sp anomalies over collapse conduits correspond to downward flowing groundwater however before sp surveys can be reliable indicators of conduit flow sp from et soil conductivity changes redox electrode effects and cultural noise must be better understood a year of continuous sp monitoring with two grids of approximately 15 pb pbcl kcl nonpolarizing electrodes each was combined with high resolution ground penetrating radar surveys and intermittent water table monitoring over two small covered karst conduits in tampa florida usa although variations

from gullies to mountain belts a review of sediment budgets at various scales this paper reviews the state of the art in the concept as well as in the application of sediment budgets in sedimentary research sediments are a product of mass dispersal at the earth surface and take part in global cycles sediment budgets aim at quantifying this mass transfer based on the principle of mass conservation and are the key to determine ancient fluxes of solid matter at the earth surface this involves fundamental questions about the interplay of uplift climate and denudation in mountain belts and transfer of sediments from the continents to the oceans as well as applied issues such as soil and gully erosion reservoir siltation and coastal protection first after introducing basic concepts relevant scales and methodologies the different components of quaternary routing systems from erosion in headwaters river systems glacial and paraglacial systems lakes deltas estuaries coasts shelves epicontinental seas and deep sea fans are discussed in terms of their sediment budget most suitable are sedimentologically closed or semi closed depositional environments e g alluvial fans lakes deltas and deep sea fans in a second step the dynamics of passive active and collisional tectonic settings and sediment budgets in related sedimentary basins are explored and new concepts of sediment portioning at large geodynamic scales are introduced ancient routing systems are more or less incomplete and may be intensively fragmented or destroyed in active tectonic settings in terms of sedimentary basin types rifts intracontinental and epicontinental settings are preferred objects of sediment budgets because of their persistence and relatively simple overall sedimentary architecture however closing basins such as foreland forearc retroarc piggy back and wedge top basins may provide excellent snapshots of orogenic sediment fluxes in a third step the large long lived routing systems of the amazon the ganges brahmaputra and the rhine are reviewed for each system estimates of either sediment volumes mass or sediment fluxes of continental and marine subsystems have been compiled in order to receive a complete routing in terms of mass conservation for specific time periods since the late glacial maximum as well as the cenozoic following lessons can be taken from these case studies i depositional centers and fluxes show strong shifts in space and time and call for caution when simply looking at subsystems ii the response times of these large systems are within the milankovich time interval thus lower than predicted from diffusion models iii cyclic routing of sediments in continental basins is much more dominated by climate human control than by eustacy and iv at long time scales ultimate sinks win over intermittent storage it is concluded from this review that the quantitative understanding of global sediment cycling over historic and geologic time and its response to allogenic forcing is still in its infancy and further research is needed towards a holistic view of sediment routing systems at various temporal and spatial scales and their coupling with global biogeochemical cycles this includes i to better determine response times of large routing systems by linking quaternary with cenozoic sediment budgets and continental with marine sub systems ii to combine advanced provenance techniques with sediment budgets in order to reconstruct ancient systems iii to study sediment partitioning at the basin scale iv to reconcile continental supply dominated sequence stratigraphy with the eustatic dominated marine concept and iv to account for non actualism of ancient systems with respect to their erosion and transport mode in particular during glaciations and pronounced arid intervals glacial and eolian sediment routing may cross over hydrologic boundaries of drainage basins thus challenging the principle of mass conservation

active tectonics and earthquake potential of the myanmar region this paper describes geomorphologic evidence for the principal neotectonic features of myanmar and its immediate surroundings we combine this evidence with published structural geodetic and seismic data to present an overview of the active tectonic architecture of the region and its seismic potential three tectonic systems accommodate oblique collision of the indian plate with southeast asia and extrusion of asian territory around the eastern syntaxis of the himalayan mountain range subduction and collision associated with the sunda megathrust beneath and within the indoburman range and naga hills accommodate most of the shortening across the transpressional plate boundary the sagaing fault system is the predominant locus of dextral motion associated with the northward translation of india left lateral faults of the northern shan plateau northern laos thailand and southern china facilitate extrusion of rocks around the eastern syntaxis of the himalaya all of these systems have produced major earthquakes within recorded history and continue to present major seismic hazards in the region

slip vectors and stretching of the sumatran fore arc slip vectors from thrust earthquakes at the java trench southwest of sumatra demonstrate that the sumatran fore arc is not a single rigid plate that is translated to the northwest by oblique plate convergence instead they indicate arc parallel stretching of the fore arc at a uniform strain rate of 3 4 x 10 8 yr the northwestward motion of the fore arc relative to the upper plate southeast asia increases from near zero at the sunda strait to 45 60 mm yr in northwest sumatra and should result in variable slip rates on the sumatran fault

investigation of groundwater flow in karst areas using component separation of natural potential measurements the natural electrical potential np method also known as self potential spontaneous potential and streaming potential sp has been used to locate areas of groundwater flow in karst terrane np is the naturally occurring voltage at the ground surface resulting from ambient electrical currents within the earth the measurement of np can be used to characterize groundwater flow in karst terrane because electrical potential gradients are generated by the horizontal flow of water along fractures or conduits and the vertical infiltration of water into fractures or shafts np data from a site on the mitchell plain of southern indiana usa revealed that np data can be decomposed into three components topographic effect residual np and noise at this site np was inversely proportional to elevation but the correlation varied with time the topographic correction factor varied from 2 5 to 1 2 mv m np change per unit elevation increase with an average linear correlation coefficient r of 0 95 because the site slopes toward an adjacent creek that is the local groundwater discharge zone one possible explanation for this effect is a streaming potential mechanism generated by groundwater movement toward the creek the residual np data revealed three negative anomalies at the survey area two of them coincide with sinkholes a part of the third anomaly is coincident with a small valley and concentrated infiltration does occur at this elevation in other valleys at the site as evidenced by the existence of sinkholes however the dispersed low magnitude nature of the third anomaly does not prove the existence of concentrated groundwater recharge activity

modification of the quaternary stratigraphic framework of the inner continental shelf by holocene marine transgression an example offshore of fire island new york abstract the inner continental shelf off fire island new york was mapped in 2011 using interferometric sonar and high resolution chirp seismic reflection systems the area mapped is approximately 50 km long by 8 km wide extending from moriches inlet to fire island inlet in water depths ranging from 8 to 32 m the morphology of this inner continental shelf region and modern sediment distribution patterns are determined by erosion of pleistocene glaciofluvial sediments during the ongoing holocene marine transgression much of the shelf is thus an actively forming ravinement surface remnants of a pleistocene outwash lobe define a submerged headland offshore of central fire island east of the submerged headland relatively older pleistocene outwash is exposed over much of the inner continental shelf and covered by asymmetric sorted bedforms interpreted to indicate erosion and westward transport of reworked sediment erosion of the eastern flank of the submerged pleistocene headland over the last 8000 years yielded an abundance of modern sand that was transported westward and reworked into a field of shoreface attached ridges offshore of western fire island west of the submerged headland erosion of pleistocene outwash continues in troughs between the sand ridges resulting in modification of the lower shoreface comparison of the modern sand ridge morphology with the morphology of the underlying ravinement surface suggests that the sand ridges have moved a minimum of 1000 m westward since formation comparison of modern sediment thickness mapped in 1996 1997 and 2011 allows speculation that the nearshore shoreface sedimentary deposit has gained sediment at the expense of deflation of the sand ridges

geologic framework influences on the geomorphology of an anthropogenically modified barrier island assessment of dune beach changes at fire island new york antecedent geology plays a crucial role in determining the inner shelf nearshore and onshore geomorphology observed in coastal systems however the influence of the geologic framework on a system is difficult to extract when evaluating responses to changes due to storms and anthropogenic modifications and few studies have quantified the potential for these influences in dune beach environments this study evaluates topographic change to the dune beach system at fire island new york over a ten year period 1998 2008 at two sites representing eastern and western reaches of the island where morphology has been shown to vary the sites are situated along swaths of coast eroding differentially and where the inner shelf geologic framework differs substantially fewer large storms occurred in the first half of the study period compared with the later part of the study period which includes several severe and prolonged extratropical storms additionally a major beach replenishment project was conducted at one of the study sites topographic data from lidar and rtk gps surveys are used to construct high resolution 3d surfaces which are used to determine volumetric change and to extract 2d alongshore features and profiles for analysis the study sites help to further characterize morphologic differences between eastern and western reaches of the island the western site displays higher sand volumes lower dunes and a lower gradient profile slope when compared with the eastern site in addition to these fundamental morphologic differences the two sites also differ significantly in their response to coastal storms and in the fact that their replenishment histories are different the replenished areas show reduced vulnerability to storms through minimal volume loss and shoreline accretion that should be considered when evaluating the response of replenished areas to episodic events we propose that site specific differences evident throughout the study period can be linked to alongshore variations in the framework geology of the system anthropogenic modifications may have intensified differences already inherent in the system

imaging the geometry of cimandiri fault zone based on 2d audio magnetotelluric amt model in nyalindung sukabumi indonesia we present an interpretation of newly acquired audio magnetotelluric data to reveal the subsurface geometry of cimandiri fault zone one of the major active faults in the western part of java the line section is 25 km long in a nearly north south direction across the axes of cfz with 24 stations of 750 1200 m spacing intervals the 2d amt inversion model shows two conductive zones in the southern part that may be associated to the miocene rocks of the southern mountains and a conductive zone in the northern part that is likely to be associated with gunung walat fold belt the subsurface structures of the southern mountains are dominated by south dipping thrusts that may uplift the shallow marine sediments shallow seismicity occurred around cfz indicating the activity of these blind thrusts

a mesoscale sediment budget for long island new york abstract a sediment budget encompassing the 140 km shoreline from montauk point to fire island inlet new york derived longshore transport rates for 25 coastal cells using comparative surveys the study area along the south shore of long island a generally straight coast of mainland and barrier island beaches includes the eroding headland at montauk point three jettied inlets two groin fields and three barrier beaches bridging between small scale quantitative surveys and large scale regional geology the sediment budget provides a mesoscale view and quantitative estimates of key coastal processes in the area results integrate changes between the foredunes and lower foreshore to the estimated depth of closure 9 to 12 m below mean sea level for a 24 5 year period 1955 1979 beach fills and losses to washovers and breach channels are incorporated in the analysis the results confirm net westerly transport and provide the first evidence that shoaling in fire island inlet long estimated to be 400 000 m 3 yr is due primarily to cannibalization of the immediate updrift compartments particularly erosion of the foreshore below mean low water this lowers estimates of longshore transport rates along most of the study area compared with previous estimates the offshore source attributed by others to account for fire island s stability appears to be trailing ebb shoals lagging behind inlet migration jettied inlets in the central study area intercept some longshore transport but since stabilization circa 1955 have been ebb dominant preserving the littoral budget seaward of the strandline littoral losses to the lagoons by inlets or washovers were insignificant over the period however breach channels if not closed soon after storms were found to offset years of ebb dominance in jettied inlets by depositing major flood deltas beach fills had measurable and positive effect on the sediment budget along the western half of the study area through the early 1970s the volume of beach fills since 1975 has diminished to about 10 of the earlier rate a field of 15 groins in the central study area is shown to trap 100 of the longshore transport and produce a local drift reversal rates of accretion within the groin cells and erosion along the downdrift compartment dwarf the average rates of change for the majority of littoral compartments in the study area

tectonic geomorphology of the san andreas fault zone from high resolution topography an example from the cholame segment abstract high resolution topographic data along fault zones are important aids in the delineation of recently active breaks a 15 km long portion of the south central san andreas fault saf along the southern cholame segment contains well preserved tectonic landforms such as benches troughs scarps and aligned ridges that indicate recurring earthquake slip recently acquired lidar topographic data along the entire southern saf b4 project have shot densities of 3 4 m 2 computed from the lidar returns digital elevation models dems of 0 25 to 0 5 m resolution using local binning with inverse distance weighting and 0 8 m or larger search radii depict the tectonic landforms at paleoseismic sites well enough to assess them confidently mapping of recently active breaks using a lidar only based approach compares well with aerial photographic and field based methods the fault zone varies in width from meters to nearly 1 km and is comprised of numerous en echelon meter to kilometer length overlapping sub parallel fault surfaces bounding differentially moving blocks that elongate parallel to the saf the semantic variations of what constitutes active and the importance of secondary traces influence the breadth and complexity of the resulting fault trace maps

neotectonics of the sumatran fault indonesia the 1900 km long trench parallel sumatran fault accommodates a significant amount of the right lateral component of oblique convergence between the eurasian and indian australian plates from 10 n to 7 s our detailed map of the fault compiled from topographic maps and stereographic aerial photographs shows that unlike many other great strike slip faults the sumatran fault is highly segmented cross strike width of step overs between the 19 major subaerial segments is commonly many kilometers the influence of these step overs on historical seismic source dimensions suggests that the dimensions of future events will also be influenced by fault geometry geomorphic offsets along the fault range as high as 20 km and may represent the total offset across the fault if this is so other structures must have accommodated much of the dextral component of oblique convergence during the past few million years our analysis of stretching of the forearc region near the southern tip of sumatra constrains the combined dextral slip on the sumatran and mentawai faults to be no more than 100 km in the past few million years the shape and location of the sumatran fault and the active volcanic arc are highly correlated with the shape and character of the underlying subducting oceanic lithosphere nonetheless active volcanic centers of the sumatran volcanic arc have not influenced noticeably the geometry of the active sumatran fault on the basis of its geologic history and pattern of deformation we divide the sumatran plate margin into northern central and southern domains we support previous proposals that the geometry and character of the subducting investigator fracture zone are affecting the shape and evolution of the sumatran fault system within the central domain the southern domain is the most regular the sumatran fault there comprises six right stepping segments this pattern indicates that the overall trend of the fault deviates 4 clockwise from the slip vector between the two blocks it separates the regularity of this section and its association with the portion of the subduction zone that generated the giant m w 9 earthquake of 1833 suggest that a geometrically simple subducting slab results in both simple strike slip faulting and unusually large subduction earthquakes

implications of the diffuse deformation of the indian ocean lithosphere for slip partitioning of oblique plate convergence in sumatra oblique plate convergence between indian ocean lithosphere and continental crust of the sunda plate is distributed between subduction on the sunda megathrust and upper plate strike slip faulting on the sumatran fault zone in a classic example of slip partitioning over the last decade a destructive series of great earthquakes has brought renewed attention to the mechanical properties of these faults and the intervening forearc crustal block while observations of forearc deformation over the earthquake cycle indicate that the forearc crust is fundamentally elastic the spatial pattern of slip vector azimuths for earthquakes sourced by rupture of the sunda megathrust is strongly inconsistent with relative motion of two rigid plates permanent and distributed deformation therefore occurs in either the downgoing lithospheric slab or the overriding forearc crust previous studies have inferred from geodetic velocities and geological slip rates of the sumatran fault that the forearc crust is undergoing rapid trench parallel stretching using new geological slip rates for the sumatran fault and an updated decadal gps velocity field of sumatra and the forearc islands we instead show that permanent deformation within the forearc sliver is minor and that the sumatran fault is a plate boundary strike slip fault the kinematic data are best explained by diffuse deformation within the oceanic lithosphere of the wharton basin which accommodates convergence between the indian and australian plates and has recently produced several large earthquakes well offshore of sumatra the slip partitioning system in sumatra is fundamentally linked with the mechanical properties of the subducting oceanic lithosphere

calculating shoreline erosion potential using nearshore stratigraphy and sediment volume outer banks north carolina 1 despite the acknowledged influence of coastal geological framework on the behavior of beaches and barrier islands and a wealth of geological and bathymetric observations from the inner shelf quantitatively connecting those observations to shoreline behavior has been difficult nearshore geologic and morphologic variability described by recent research is not well represented by conventional geologic parameters such as mean grain size and shoreface slope used in most shoreline change models we propose that total nearshore sediment volume as calculated to a continuous seismic reflection surface provides a flexible and robust metric for use in the prediction of shoreline change this method of determining the volume of sediment in the nearshore accounts for three dimensional sandbar morphologies and heterogeneous seafloor sediments the decadal scale shoreline change rate for northeastern north carolina is significantly correlated to the volume of sediment in the nearshore when a geologically defined base is used in volume determinations suggesting that the shallow stratigraphic framework of transgressive coasts is an important influence on decadal shoreline behavior nearshore sediment volume was overestimated when an arbitrary depth constant baseline was used and was not correlated to decadal shoreline change this implies that a volume metric which accounts for both framework geology and variable seafloor morphology better represents the geologic character of the shoreface and may help to improve existing models of shoreline change an empirical model of regional shoreline erosion potential demonstrates the importance of incorporating nearshore sediment volume shallow framework geology and surface morphology when predicting seasonal to decadal shoreline evolution

characterization of slow slip rate faults in humid areas cimandiri fault zone indonesia in areas where regional tectonic strain is accommodated by broad zones of short and low slip rate faults geomorphic and paleoseismic characterization of faults is difficult because of poor surface expression and long earthquake recurrence intervals in humid areas faults can be buried by thick sediments or soils their geomorphic expression subdued and sometimes undetectable until the next earthquake in java active faults are diffused and their characterization is challenging among them is the ene striking cimandiri fault zone cumulative displacement produces prominent ene oriented ranges with the southeast side moving relatively upward and to the northeast the fault zone is expressed in the bedrock by numerous ne w and nw trending thrust and strike slip faults and folds however it is unclear which of these structures are active we performed a morphometric analysis of the fault zone using 30 m resolution shuttle radar topography mission digital elevation model srtm dem we constructed longitudinal profiles of 601 bedrock rivers along the up thrown ranges along the fault zone calculated the normalized channel steepness index ksn identified knickpoints and use their distribution to infer relative magnitudes of rock uplift and locate boundaries that may indicate active fault traces we compare the rock uplift distribution to surface displacement predicted by elastic dislocation model to determine the plausible fault kinematics the active cimandiri fault zone consists of six segments with predominant sense of reverse motion this geometric characterization implies a maximum earthquake magnitude along its 100 km length of m7 3 but its geometric complexity suggests greater segmentation and smaller events

noise reduction in long term self potential monitoring with travelling electrode referencing the long term monitoring of the electric self potential sp in geophysical systems is affected by electrode degradation and drift this error contribution can be reduced if the electrodes of measuring dipoles are referenced to the same accessory electrode moved in turn at each pole the benefit of this travelling electrode referencing scheme ter has been evaluated in a dedicated experiment performed from march 2000 to march 2001 at tribhuvan university nepal two prototype monitoring points separated by 55 m have been instrumented with pairs of lead lead chloride petiau electrodes installed in buckets filled with salted bentonite at a depth of 1 and 2 meters the electrical potential at 1 and 2 meters depth was also accessible from the surface by pipes filled with salted bentonite over one year the measurement error defined as the standard deviation of the difference between the measured potential and the true sp at a given time is estimated to be 5 mv this error value is reduced to less than 1 mv with ter after correction a smooth annual variation with amplitude of 10 to 15 mv is observed and is interpreted as streaming potentials associated with the monsoon and subsequent drying these results provide significant guidelines for precision long term sp monitoring in particular in tropical volcanic or tectonically active regions

1857 slip on the san andreas fault southeast of cholame california sieh and jahns 1984 forecasted that the next moderate parkfield earthquake might trigger a major earthquake along a fault segment greater than 30 km long southeast of cholame their forecast assumed 1 the slip was 3 4 m in 1857 and characteristic of the segment 2 a slip rate of 3 4 cm yr and 3 full strain release in earthquakes this study represents an independent measurement of channel offsets on 1 2400 scale low sun aerial photographs and by field investigation to estimate the amount of 1857 slip although rainfall is only moderate 30 cm yr few reliable offsets of less than 20 m persist here because cattle grazing and agricultural disking of soft sediments on the steep terrain greatly aggravate erosion reconstruction of offset geometry and size depends heavily on assumptions made about the post 1857 erosion most of the apparent 3 to 4 m offsets of sieh and jahns 1984 can also be measured as 2 to 3 m larger with equal or lower uncertainty the four offsets judged as most reliable range between 5 4 and 6 7 m and the 11 offsets of medium high reliability average 5 8 0 3 m data are too sparse and ambiguous to resolve details of the 1857 slip for this segment but it is distinctly less than the 9 m of the carrizo plain and more than the 3 4 m previously estimated further trenching may refine some measurements but probability calculations for a cholame segment earthquake must allow for large observer dependent uncertainty in the 1857 slip although the probability of an m 7 cholame event seems less than that suggested by a 3 5 m characteristic earthquake model it remains among the highest in the state

response of wave dominated and mixed energy barriers to storms wave dominated and mixed energy barriers are extremely dynamic landforms responding to processes operating over a spectrum of time scales ranging from daily to monthly fluctuations related to storm and post storm conditions to century to millennium scale evolution driven by relative sea level change two types of storms are of particular relevance warm core tropical and cold core extratropical cyclones both are responsible for generating very large waves highly energetic surf zone dynamics and sediment transport elevated inshore water levels and extensive morphological responses all cyclones are affected by climate change which governs their frequency intensity and tracks barrier storm response is primarily governed by maximum storm runup and barrier morphology as conceptualised in abby sallenger s storm impact scale model sallenger 2000 this model defines four storm impact regimes and includes erosive as well as accretionary responses on the erosion side the swash regime drives bar and berm flattening the collision regime is marked by dune scarping and beach lowe the overwash regime leads to dune scouring and channel incision and the inundation regime may result in barrier destruction on the deposition side storm berms and beach ridges may form and accrete in the swash and collision regimes localised vertical beach and barrier accretion are associated with the collision and overwash regimes and washover deposition takes place in the overwash and inundation regimes site specific factors play a key role in moderating the morphological response and include storm characteristics type duration and track longshore sediment supply upwelling downwelling currents coastal setting and inner shelf topography the response of a barrier to a tropical or extratropical cyclone can however not be considered in isolation and has to be appreciated in a longer temporal context involving morphological preconditioning due to antecedent wave and water level conditions additionally a simple process response approach of the cause and effect type is inappropriate and a more complex conceptual framework involving thresholds feedbacks resilience and vulnerability will need to be adopted a useful way to visualise and conceptualise more complex storm behaviours and the longer term vulnerability of barriers is the resilience trajectory which maps out the changes in barrier geometry elevation and width over various time scales from weeks to years or even longer and under varying forcing conditions including changes in storminess and sea level rise an increased understanding of barrier response to storms and sequences of storms is required to better quantify long term barrier response to climate change high resolution and comprehensive decadal records of barrier response to storms are a prerequisite to achieve this ambition linking site specific coastal settings hydrodynamic drivers and morphological responses and allowing the recognition of recovery and impact dominated phases the enhanced insights in barrier response to extreme events must then be incorporated into improved coastal response models to help predict the impacts of future climate change on wave dominated and mixed energy barriers around the world 2013 elsevier b v

the kinematics of crustal deformation in java from gps observations implications for fault slip partitioning abstract our understanding of seismic risk in java has been focused primarily on the subduction zone where the seismic records during the last century have shown the occurrence of a number of tsunami earthquakes however the potential of the existence of active crustal structures within the island of java itself is less well known historical archives show the occurrence of several devastating earthquake ruptures north of the volcanic arc in west java during the 18th and the 19th centuries suggesting the existence of active faults that need to be identified in order to guide seismic hazard assessment here we use geodetic constraints from the global positioning system gps to quantify the present day crustal deformation in java the gps velocities reveal a homogeneous counterclockwise rotation of the java block independent of sunda block consistent with a ne sw convergence between the australian plate and southeast asia continuous gps observations show a time dependent change in the linear rate of surface motion in west java which we interpret as an ongoing long term post seismic deformation following the 2006 m w 7 7 java earthquake we use an elastic block model in combination with a viscoelastic model to correct for this post seismic transient and derive the long term inter seismic velocity which we interpret as a combination of tectonic block motions and crustal faults strain related deformation there is a north south gradient in the resulting velocity field with a decrease in the magnitude towards the north across the kendeng thrust in the east and the baribis thrust in the west we suggest that the baribis thrust is active and accommodating a slow relative motion between java and the sunda block at about 5 0 2 mm yr we propose a kinematic model of convergence of the australian plate and the sunda block involving a slip partitioning between the java trench and a left lateral structure extending e w along java with most of the convergence being accommodated by the java megathrust and a much smaller parallel motion accommodated along the baribis 5 0 2 mm yr and kendeng 2 3 0 7 mm yr thrusts our study highlights a correlation between the geodetically inferred active faults and historical seismic catalogs emphasizing the importance of considering crustal fault activity within java in future seismic assessments

vegetation and climate change in west java indonesia during the last 135 000 years abstract sedimentological and palynological analyses of two sediment cores from the intramontane bandung basin java indonesia provide the first palaeoclimatic record for the indonesian region covering the last 135 000 years our data indicate anomalously dry conditions for the penultimate glacial and very warm and humid conditions during the last interglacial during the last glacial period fresh water swamp forests of the bandung plain were replaced by open swamp vegetation dominated by grasses and sedges indicating a change to considerably drier climatic conditions possibly as a consequence of lower sea levels at the onset of glacial conditions for the last glacial maximum temperatures 4 7 c lower than at present are recorded

scaling properties of estuarine beaches abstract estuarine beaches near large rivers are dynamic systems constantly shaped by tides waves and fluvial sediment inputs however little research has been done on the intrinsic characteristics of these geomorphic systems using eleven high resolution bathymetries our results show that human disturbance mingled with natural forcings have induced bathymetric changes in nanhui beach in the changjiang estuary china isobaths display a fractal geometry with a lower fractal dimension when tides smooth the bathymetry and a higher dimension when waves dominate rates of sediment accretion and erosion present a gaussian distribution driven by tidal and wave action episodic extreme wave forcing or frequent land reclamation is responsible for the intermittent adjustment of the estuarine beach bathymetry after these events the distribution of erosion and accretion becomes power law possibly indicating disequilibrium the fractal dimension of isobaths and the distribution of erosion and deposition rates can therefore be used as metrics to determine the dominant processes in estuarine beaches and whether the system is close to equilibrium or not

cross coupled flow modeling of coincident streaming and electrochemical potentials and application to subglacial self potential data 1 this study aims to demonstrate that self potential measurements can yield unique information about subglacial drainage conditions which has so far been doubtful at the bed of warm based glaciers arborescent and distributed drainage systems interact and streaming and electrochemical potentials coincide a key secondary aim of this study is therefore the development of a mathematical framework for the analysis of self potentials generated by such interacting flow systems we consider cross coupling between hydraulic electrical and chemical driving forces and apply the resulting model solution to self potential data recorded beneath haut glacier d arolla switzerland we find that 1 the streaming and electrochemical contributions to the total self potential signal can be separated mathematically 2 streaming potentials directly reflect the direction of water flow at the glacier bed 3 combination of streaming potentials with hydraulic conductivity estimates from slug tests allows estimation of in situ subglacial water flow velocities 4 the subglacial zeta potential calculated from estimated values of the streaming coupling coefficient is small 0 022 v due to systematic flushing of clay minerals from the channel area during the melt season and 5 uncertainties in exact electrode location in the borehole are unlikely to produce self potential noise self potential measurements may therefore yield unique information about subglacial drainage conditions and especially the direction and velocity of in situ subglacial water flow are difficult to obtain by other methods we further anticipate that our mathematical framework will be applicable to other areas of subsurface hydrology especially where spatially distributed seepage feeds preferential flow pathways

seismic history and seismotectonics of the sunda arc historic records of the last 300 years reveal two great interplate earthquakes 1833 mw 8 1861 mw 8 8 which ruptured major segments of the sumatra fore arc in western indonesia a significant percentage of interplate slip along this portion of the plate boundary appears to occur seismically the ends of these rupture zones are coincident with clusters of large ms 7 and moderate 6 ms 7 shocks and with heterogeneities in the plate interface as inferred from geologic and geophysical data the northern extent of the 1833 rupture zone is coincident with a group of moderate and large earthquakes a structural arch in the fore arc and a fracture zone on the subducted plate the southern portion is coincident with a very prominent cluster and the along strike extension of a sediment filled trough on the subducted plate prior to this study sumatra was characterized as relatively aseismic as inferred from the lack of great earthquakes in the instrumental record of this century java and the lesser sunda islands had major ms 6 earthquakes in the historic record but none are of the same magnitude as the great events near sumatra there is no clear evidence that shocks in the java fore arc were interplate events yet geophysical data indicate recent uplift of the trench slope break and a change in strike of the trench axis where the northernmost flank of the roo rise a prominent bathymetrie high appears to be interacting with the fore arc this feature was formed at a ridge crest and is more buoyant and thus more difficult to subduct than the surrounding seafloor there is no increase in seismicity associated with this tectonism however that may indicate a lack of contact between the crystalline portions of the plates at this time we infer that a majority of slip on the plate interface near java occurs aseismically the variation in occurrence of great interplate earthquakes along the sunda arc may be interpreted in terms of a model that attributes variation in interplate coupling to the age of the subducted lithosphere great interplate earthquakes occur near sumatra where the age of the youngest crust is 46 ma the characteristics of the sunda arc and analogies with pacific arcs imply that the entire length of sumatra has the potential to produce great thrust earthquakes its seismic potential should be considered high as there has been no recurrence of the great events of 1833 and 1861 in contrast no such events have been reported off java and the lesser sunda islands where the oldest crust is 152 ma the plate interface near java and the lesser sunda islands should be considered to have low seismic potential

teleseismic relocation and assessment of seismicity 1918 2005 in the region of the 2004 mw 9 0 sumatra andaman and 2005 mw 8 6 nias island great earthquakes the m w 9 0 2004 sumatra andaman islands and m w 8 6 nias island great earthquake sequences have generated over 5000 catalog reported earthquakes along 1700 km of the sumatra andaman and western sunda regions studies of prior regional seismicity have been limited to global catalog locations that often have poorly constrained epicenters and depths approximately 3650 teleseismically well recorded earthquakes occurring in this region during the period 1918 2005 are relocated with special attention to focal depth reduced uncertainties of epicenters and depths in the region on the order of 15 and 10 km respectively foster interpretation of focal mechanism data and provide additional details about the subducting indian and australian plates the revised earthquake dataset reveals a sharp delineation between aftershocks of the 2004 and 2005 earthquakes near simeulue island and a steepening in slab dip from south to north the downdip width of the aftershock zone of the 2004 m w 9 0 earthquake varies from 200 km at its northern end to 275 km at its southern end and events located between 35 and 70 km focal depth occur more frequently in the southernmost section of this aftershock zone outer rise and near trench normal and strike slip faulting earthquakes also increase in frequency following the 2004 and 2005 earthquakes earthquake swarms triggered along the andaman backarc spreading center both north of sumatra and near siberut island 100 km south of the nias island aftershock sequence illustrate the complex and variable nature of seismicity following these great earthquakes

fluid flow near reservoir lakes inferred from the spatial and temporal analysis of the electric potential electric self potential sp variations have been monitored continuously from 1995 to 1998 at 14 points on a ridge separating the roselend and la gittaz reservoir lakes in the french alps the lakes have level variations of at least 50 m over yearly cycles seasonal variations of sp associated with lake level variations are observed on five points of the array for three points located on the banks of the lakes a positive correlation to the lake level variations is observed with a maximal amplitude of about 180 mv corresponding to an average response of 2 4 mv per meter of water for two points located on the bottom of each lake the correlation is negative with a maximal magnitude of about 50 mv corresponding to an average response of 1 1 mv per meter of water two independent temporary electrical arrays located on the banks of each lake confirm these measurements and allow a better spatial characterization of the sources associated with the observed sp variations in particular near the roselend lake the electrical response to lake level variations is increasing for decreasing altitude the measured sp variations are proposed to result from the electrokinetic coupling associated with a vertical groundwater flow connecting a constant pore pressure source to the bottom of the lakes numerical modeling indicates that the spatial variation of the response and the nonlinear response observed at one point can be explained by leakage currents in the conductive lake water the values of the streaming potential coefficient spc measured in the laboratory with crushed rock samples from the site range from 14 to 50 mv 0 1 mpa for an electrolyte resistivity of 40 m and are compatible to first order with the magnitude of the observed seasonal sp variations a detailed quantitative electrokinetic modeling is currently limited mainly by the poor knowledge on the contribution of electrical leakage currents and the local variability of the spc this experiment indicates that spatial and temporal variations of the electric potential are promising tools to characterize and monitor shallow groundwater flow and provide practical data for the investigation of groundwater flow associated with volcanic or tectonic activity

longshore sediment transport and foreshore change in the swash zone of an estuarine beach abstract estuarine beaches often lack well developed surf zones incident waves break and convert directly to swash on the steep foreshore resulting in greater influence of the swash zone in generating longshore flows and sediment transport this study was conducted to evaluate longshore sediment transport in the swash zone of an eroding estuarine beach and relate transport rates to changes in beach position and volume downdrift of a shore perpendicular structure field data were gathered on a sandy beach on the bay side of fire island new york usa in a short fetch 12 15 km microtidal mean range 0 21 m environment wave and swash processes beach changes and sediment tracer and trapping experiments were conducted during strong onshore winds in march and april 2012 daily topographic surveys of the beach revealed pulses of sediment movement alongshore at small temporal daily and spatial 5 m scales the mid foreshore retreated 2 75 m from the beginning to the end of the 24 days of monitoring this retreat was associated with a loss of 2 1 m3 of sediment per meter of shoreline length the greatest amount of foreshore retreat during a single storm event was 1 27 m associated with a volume loss of 0 9 m3 of sediment per meter mean wind speed on that day was 11 3 m s 1 with a maximum of 18 2 m s 1 significant offshore wave height at the time of maximum wind speed was 0 30 m mean significant wave heights ranged from 0 12 to 0 26 m during the five times when trapping occurred resulting in mean longshore swash velocities of 0 08 to 0 23 m s 1 and transport rates ranging from 0 413 to 1 516 m3 h 1 the longshore sediment transport rates are similar to rates gathered under similar longshore current velocities on microtidal low energy beaches transport rates on beaches in sheltered environments can differ from rates calculated using existing formulas that may be more appropriate for high energy beaches where a greater proportion of sediment is transported in the surf zone than in the energetic swash zone under plunging breakers transport rates calculated from three existing formulae bagnold 1963 cerc 1984 kamphuis 2002 revealed that estimates from bagnold compared most favorably with measured rates because of direct measurements of longshore current velocities rates of erosion on beaches in short fetch environments can be high despite low wave energies because the low narrow beaches have little volume magnifying the importance of seemingly low rates of transport in the swash

self potential and ground temperature at merapi volcano prior to its crisis in the rainy season of 2000 2001 abstract rainwater infiltration into the active lava dome of merapi volcano central java has often been suggested as a triggering mechanism for partial dome collapse and subsequent eruptive behavior however the phenomenon has not been systematically investigated we use a multi parametric approach to study the interaction of the hydrologic and magmatic system near the lava dome prior to its crisis in early 2001 we describe the hardware concept for a continuous monitoring system for self potentials u sp and ground temperature t installed in august 2000 at the solfatara woro only 150 m from the active lava dome relating the data from this station to measurements of rainfall air pressure solfatara temperature and seismicity several effects can be distinguished a a long term correlation is observed between electrode temperature difference and sp with estimated coupling coefficients of 2 1 0 5 mv c b after individual rainfall events u t signatures show a typical pattern of positive charge accumulation at the hot electrodes near the fumarolic vents c an exceptional anti correlation between u and t is observed in january 2001 during a period of rapid dome growth prior to the collapse and eruptive crisis d wavelet analysis of sp reveals the sporadic occurrence of periodic fluctuations with a clear 12 h s2 component because of their amplitude of up to 100 mv km and their periodicity s2 but not 24 h or lunar 12 h 25 min these fluctuations are unlikely to be caused by natural magnetic field variation or by earth tides instead they do seem correlated but not in phase with atmospheric pressure changes we discuss effects a d in the framework of source mechanisms related to water lava interactions

earthquake geology of the lembang fault west java indonesia abstract the lembang fault is a major fault in western java that skirts the northern edge of bandung one of indonesia s largest cities just south of the active tangkuban perahu volcano although it has no recorded or historical large earthquakes the lembang fault shows obvious geomorphic evidence of recent activity and has long been thought to be active in this study we use geomorphic analysis to unequivocally establish that the fault has a dominantly sinistral sense of movement with a slip rate of 1 95 3 45 mm yr this proves that the fault is accommodating trench parallel slip resulted from a slight obliquity in plate convergence at the javatrench with a length of 29 km this suggests that the lembang fault could produce a mw 6 5 7 0 earthquake with a recurrence time of 170 670 years we also conducted paleoseismological trenching of the lembang fault and found evidence for at least 3 earthquakes in the 15th century 2300 60 bce and 19 620 19 140 bp the 2300 60 bce earthquake had a measurable vertical displacement of 40 cm which is consistence with a mw 6 5 earthquake this is the first mapping of a source of crustal earthquakes in java indonesia the world s most densely populated island in one of its most tectonically active areas the lembang fault and other faults in java are likely to pose substantial risk to not only bandung but many of java s major urban agglomerations

challenging assumptions of future coastal habitat development around the uk one habitat management requirement forced by 21st century relative sea level rise rslr will be the need to re comprehend the dimensions of long term transgressive behaviour of coastal systems being forced by such rslr fresh approaches to the conceptual modelling and subsequent implementation of new coastal and peri marine habitats will be required there is concern that existing approaches to forecasting coastal systems development and by implication their associated scarce coastal habitats over the next century depend on a certain premise of orderly spatial succession of habitats this assumption is shown to be questionable given the possible future rates of rslr magnitude of shoreline retreat and the lack of coastal sediment to maintain the protective morphologies to low energy coastal habitats of these issues sediment deficiency is regarded as one of the major problem for future habitat development examples of contemporary behaviour of uk coasts show evidence of coastal sediment starvation resulting from relatively stable rslr anthropogenic sealing of coastal sources and intercepted coastal sediment pathways which together force segmentation of coastal systems from these examples key principles are deduced which may prejudice the existence of future habitats accelerated future sediment demand due to rslr may not be met by supply and if short to medium term hold the line policies predominate long term strategies for managed realignment and habitat enhancement may prove impossible goals methods of contemporary sediment husbandry may help sustain some habitats in place but otherwise instead of integrated coastal organization managers may need to consider coastal breakdown segmentation and habitat reduction as the basis of 21st century coastal evolution and planning copyright 2006 john wiley sons ltd

neotectonic architecture of taiwan and its implications for future large earthquakes the disastrous effects of the 1999 chi chi earthquake in taiwan demonstrated an urgent need for better knowledge of the island s potential earthquake sources toward this end we have prepared a neotectonic map of taiwan the map and related cross sections are based upon structural and geomorphic expression of active faults and folds both in the field and on shaded relief maps prepared from a 40 m resolution digital elevation model augmented by geodetic and seismologic data the active tandem suturing and tandem disengagement of a volcanic arc and a continental sliver to and from the eurasian continental margin have created two neotectonic belts in taiwan in the southern part of the orogen both belts are in the final stage of consuming oceanic crust collision and suturing occur in the middle part of both belts and postcollisional collapse and extension dominate the island s northern and northeastern flanks both belts consist of several distinct neotectonic domains seven domains kaoping chiayi taichung miaoli hsinchu ilan and taipei constitute the western belt and four domains lutao lanyu taitung hualien and ryukyu make up the eastern belt each domain is defined by a distinct suite of active structures for example the chelungpu fault source of the 1999 earthquake and its western neighbor the changhua fault are the principal components of the taichung domain whereas both its neighboring domains the chiayi and miaoli domains are dominated by major blind faults in most of the domains the size of the principal active fault is large enough to produce future earthquakes with magnitudes in the mid 7 values