human impact and slope dynamics evolutionary trends in the monoclinal relief of adriatic area of central italy abstract the present work deals with a large area of the marche abruzzi monoclinal relief which is made up of a clayey sediment succession with sandy conglomeratic levels alternating at varying stratigraphic heights the east verging monocline was generated by an intense quaternary tectonic uplifting it differs approximately in the west east and in the southern directions forming three wide morphostructures the deep fluvial down cutting disjointed the monoclinal relief into a succession of high hills which give the area a typical cuesta morphology with fronts facing the western quadrants the present study aims at contributing to the knowledge of recent slope morphodynamics by analyzing the spatial distribution and state of activity of fast hydro erosion processes and superficial mass movements correlations are made between these phenomena and the morphotectonic and lithological features of the various sectors in the area with particular reference to agricultural land use the present research underlines how the badlands represent the most spectacular form of fast erosion whereas the landslide phenomena which affect the prevalently loamy clayey eluvial colluvial covers are the most widespread processes despite the distribution density and recent or current evolutionary trends are generally associated with different morphostructural features of the various sectors of the area they prove to be strictly controlled by agricultural exploitation and by the connected techniques and types of cultivation

rainfall runoff and sediment transport relations in a mesoscale mountainous catchment the river isabena ebro basin this paper examines the relations between rainfall runoff and suspended sediment transport in the isabena basin during a quasi average hydrological year the isabena is a mesoscale river basin that drains a mountainous area comprising patches of highly erodible materials badlands the paper includes an analysis of the different hydrological and sedimentary responses of the catchment to a similar rainfall thirty four floods were studied with a very variable response observed runoff coefficients ranged from 0 32 to 33 the sedimentary response was also highly variable with maximum suspended sediment concentrations ssc oscillating between 0 1 and 90 g l 1 and flood sediment loads varying from 27 to 54 000 t per hydrological event most sediment load was concentrated in spring when competent floods occur frequently pearson correlation matrix and backward stepwise multiple regression indicate that the hydrological response of the catchment is strongly correlated with total precipitation event duration and rainfall of the previous days very low correlation was observed with rainfall intensity the relation between rainfall and sediment transport followed the same trend sediment variables e g total load and ssc were significantly correlated with variables such as total rainfall and rainfall over the previous days although the significance level was lower in comparison with the runoff related variables there was again no correlation between sediment variables and rainfall intensity on going research in the area suggests that apart from rainfall factors such as sediment availability in the badlands and accumulation of sediment in the channels influences the river s sedimentary response the non linear hydrosedimentary response is reflected in the wide range of runoff coefficients and sediment loads that have been observed in response to similar amounts of precipitation

mixing of event and pre event water in a shallow entisol in sloping farmland based on isotopic and hydrometric measurements sw china

dendrogeomorphology in badlands methods case studies and prospects soil and vegetation are interacting factors controlling erosion soil degradation processes may affect the normal tree and shrub development and inversely vegetation can modulate the velocity and intensity of soil development or denudation a dendrogeomorphological approach can be used to study these interactions allowing to obtain a date and estimate mean or specific erosion rates this is especially useful in an unrecorded badlands and gullied environments where the scarce vegetation may be the only proxy available to quantify the different geomorphic processes which have occurred this paper provides a fundamental review of the dendrogeomorphological methodology applied to erosion measurement in badlands focusing on the response of the vegetation to the geomorphic processes this paper a describes the methodology developed to estimate erosion rates with exposed roots b shows new advances through case studies and finally c discusses future lines of research to reduce methodological uncertainties and for making dendrogeomorphology more widely applicable

analysis of the tsunami generated by the great 1977 sumba earthquake that occurred in indonesia abstract the great outer rise earthquake m w 8 3 occurred near the sunda trench indonesia on 19 august 1977 the earthquake has been previously studied using seismological data the earthquake generated a large tsunami that caused severe damage in sumbawa and sumba islands in indonesia the tsunami was also observed at tide gauges in australia we numerically computed a far field tsunami and we compared the observed tsunami waveforms on three tide gauges with the computed waveforms we also numerically computed the tsunami inundation and compared the observed tsunami run up of 8 m and tsunami inundation distance of 500 m in lunyuk on sumbawa island with the computed ones to explain the observed tsunami waveforms tsunami run up and tsunami inundation distance the slip amount is found to be 3 m on the assumed fault model with a fault length of 200 km and fault width of 70 km the rigidity is assumed to range between 6 0 and 6 8 10 10 n m 2 and the range of the total seismic moment is calculated to be between 2 5 and 2 9 10 21 n m m w 8 2 which is similar to those estimated by the previous seismological studies additionally we calculated the ratio between the observed tsunami run up and the computed maximum tsunami height along the coastline of lunyuk this ratio called the amplification factor may possibly be used to roughly estimate the tsunami run up from a tsunami numerical calculation result on a coarse grid system

estimate of tsunami source using optimized unit sources and including dispersion effects during tsunami propagation the 2012 haida gwaii earthquake we apply a genetic algorithm ga to find the optimized unit sources using dispersive tsunami synthetics to estimate the tsunami source of the 2012 haida gwaii earthquake the optimal number and distribution of unit sources gives the sea surface elevation similar to that from our previous slip distribution on a fault using tsunami data but different from that using seismic data the difference is possibly due to submarine mass failure in the source region dispersion effects during tsunami propagation reduce the maximum amplitudes by up to 20 of conventional linear long wave propagation model dispersion effects also increase tsunami travel time by approximately 1 min per 1 300 km on average the dispersion effects on amplitudes depend on the azimuth from the tsunami source reflecting the directivity of tsunami source while the effects on travel times depend only on the distance from the source

fault slip distribution of the 2014 iquique chile earthquake estimated from ocean wide tsunami waveforms and gps data we applied a new method to compute tsunami green s functions for slip inversion of the 1 april 2014 iquique earthquake using both near field and far field tsunami waveforms inclusion of the effects of the elastic loading of seafloor compressibility of seawater and the geopotential variation in the computed green s functions reproduced the tsunami traveltime delay relative to long wave simulation and allowed us to use far field records in tsunami waveform inversion multiple time window inversion was applied to tsunami waveforms iteratively until the result resembles the stable moment rate function from teleseismic inversion we also used gps data for a joint inversion of tsunami waveforms and coseismic crustal deformation the major slip region with a size of 100 km 40 km is located downdip the epicenter at depth 28 km regardless of assumed rupture velocities the total seismic moment estimated from the slip distribution is 1 24 1021 n m mw 8 0

identifying the water source for subsurface flow with deuterium and oxygen 18 isotopes of soil water collected from tension lysimeters and cores the conventional identification of soil water with pre event water limits deep insights into the involvement of stationary and mobile soil water in subsurface hydrological processes in three tilled sloping field plots at a hilly area of southwestern china dominated by entisols soil water collected with a suction lysimeter was distinguished from the total soil water through an analysis of the stable isotopes deuterium and oxygen 18 differences in the depth profile of soil water before and after storm events were observed and used to examine how rainwater mixes with soil water and to identify the source contribution of different fractions of soil water in subsurface flow generation only water in the 0 10 cm soil layer was significantly affected by evaporation and infiltration water in the top 5 cm layer of the soil exhibited the lowest residence time because a storm can replace a substantial proportion of the pre event water soil water at the 10 20 cm depth showed the longest residence time as indicated by its high proportion of pre event water the isotopic signatures demonstrated that piston flow and preferential flow coexisted in this soil high antecedent soil water content and high rain intensity favor the formation of piston flow the water collected with the suction lysimeter represented the mobile fraction of the pre event water in the soil which effectively participates in the generation of subsurface flow newly infiltrated rainwater did not well mix with stationary pre event water in the soil the use of recent rainfall to represent mobile soil water may provide a practical solution for overcoming the negative effect of the spatial heterogeneity of the isotopic composition of soil water on hydrograph separation results bulk soil water and lysimeter water showed significant differences in isotopic composition under low soil water content or in the top soil layer stable isotopes in bulk and lysimeter soil water should be monitored synchronously to reveal the sources and pathways of soil water and their contributions to the generation of subsurface flow in the vadose zone c 2013 elsevier b v all rights reserved

space time variability of denudation rates at the catchment and hillslope scales on the tyrrhenian side of central italy studies on denudation rates can provide insight into the influence of climate change tectonics and human activities on landscape evolution research performed in central italy has shown considerable spatial variability of denudation rates in the major river basins these studies have focused mainly on the tyrrhenian side of the italian peninsula where plio pleistocene marine deposits filling nw se elongated sedimentary basins have been uplifted during the quaternary up to several hundreds of meters above present sea level small sub catchments developed on clays are affected by sharp and or rounded edged badlands i e calanchi and biancane representing denudation hot spots in the present day morphoclimatic framework in this paper we analyze the relationships between indirectly estimated denudation rates at the catchment scale and field monitoring data at the hillslope scale we attempt to better understand and quantify all hillslope processes that contribute to seasonal variability of denudation to help with predicting the net input from hot spots to the overall estimated sediment yield at the basin outlets at the hillslope scale we discuss in particular the variability of denudation rates at calanchi and biancane badlands as a function of their different morphoevolution

msi morphometric slope index for analyzing activation and evolution of calanchi in italy article i nfo the calanchi singular calanco are a typical example of italian badlands widespread in areas with hills of clay rich sediments and rocks they appear as a very dense and rapidly evolving drainage system characterized by an alternating pattern of narrow furrows and sharp crests the calanchi can be considered as small hydrographical basins characterized by two possible drainage patterns parallel and dendritic the two patterns show both linear and areal erosion processes in this study calanchi with dendritic drainage patterns were analyzed in three different areas representative of the italian peninsular atri in the abruzzi region mount ascensione in the marche region and orcia valley in the tuscany region for each calanchi the pre erosion topographic surface was reconstructed and the value of msi morphometric slope index was calculated for the surface the volume of eroded material was estimated by comparing the pre calanchi and present surfaces we assumed that slope morphometry influences the type of erosion processes and the efficacy of these processes with respect to the amount of eroded material is a func tion of their duration we deduced that calanchi inception was contemporaneous because the duration of the processes was common to all landforms and probably due to a common climate input moreover the relations among msi eroded volume and erosion processes indicate that over a long period areally distributed surface processes contribute more to total sediment yields than channel flows

parallel implementation of dispersive tsunami wave modeling with a nesting algorithm for the 2011 tohoku tsunami because of improvements in offshore tsunami observation technology dispersion phenomena during tsunami propagation have often been observed in recent tsunamis for example the 2004 indian ocean and 2011 tohoku tsunamis the dispersive propagation of tsunamis can be simulated by use of the boussinesq model but the model demands many computational resources however rapid progress has been made in parallel computing technology in this study we investigated a parallelized approach for dispersive tsunami wave modeling our new parallel software solves the nonlinear boussinesq dispersive equations in spherical coordinates a variable nested algorithm was used to increase spatial resolution in the target region the software can also be used to predict tsunami inundation on land we used the dispersive tsunami model to simulate the 2011 tohoku earthquake on the supercomputer k good agreement was apparent between the dispersive wave model results and the tsunami waveforms observed offshore the finest bathymetric grid interval was 2 9 arcsec approx 5 m along longitude and latitude lines use of this grid simulated tsunami soliton fission near the sendai coast incorporating the three dimensional shape of buildings and structures led to improved modeling of tsunami inundation

the role of the hillside in determining the morphometric characteristics of calanchi the example of adriatic central italy abstract a typical example of badlands in the italian peninsula is the calanchi plural of calanco which may be defined as rapidly evolving very dense and hierarchical drainage systems whose genesis is controlled by mineralogical characteristics the granulometric composition of local lithotypes structural conditions hillside gradient and climate in this work some of the morphometric characteristics of the hillside were compared on a statistical basis with those of the drainage network of the calanchi for two large sample areas in adriatic central italy it was possible to demonstrate how the hillside environment strongly affects the activation of the process and the characteristics of the calanchi depending on their morphometric morphometric characteristics in particular the length inclination ratio of the hillside conditions the hydrographic pattern of the calanco system

thirty years of studies on badlands from physical to vegetational approaches a succinct review the scientific subjects addressed in the research into badlands since the publication of bryan and yair s book bryan r b and yair a editors 1982 badland geomorphology and piping geo books norwich 408 pp are briefly analysed with a steadily increasing number of papers per year attention to some aspects such as runoff generation piping and the role of lithology and soils varied whereas the percentage of studies on erosion rates increased steadily over time vegetation was not a subject of research in early papers as most of the papers dealing with vegetation were rather descriptive and published in local or limited diffusion media which contrasts with the present situation when about 40 of papers published in international journals about badlands address some aspect of vegetation however the growth in the attention paid to vegetation and erosion rates was not linked to any increase in papers dealing with badland reclamation badlands are now seen as a group of systems with some common features but diverse dynamics depending mainly on climatic and lithological drivers more attention should be paid in the future to investigating the evolution of these landforms over time mostly through modelling studies whereas emerging technologies foster detailed analyses that were not possible formerly although some badland areas determine on and off site environmental issues others are spots of landscape diversity that merit protection rather than reclamation

travel times in the vadose zone variability in space and time water travel times reflect hydrological processes yet we know little about how travel times in the unsaturated zone vary with time using the soil physical model hydrus 1d we derived time variable travel time distributions for 35 study sites within the attert catchment in luxembourg while all sites experience similar climatic forcing they differ with regard to soil types 16 cambisols 12 arenosols and 7 stagnosols and the vegetation cover 29 forest and 6 grassland we estimated site specific water flow and transport parameters by fitting the model simulations to observed soil moisture time series and depth profiles of pore water stable isotopes with the calibrated model we tracked the water parcels introduced with each rainfall event over a period of several years our results show that the median travel time of water from the soil surface to depths down to 200 cm is mainly driven by the subsequent rainfall amounts the median time until precipitation is taken up by roots is governed by the seasonality of evapotranspiration rates the ratio between the amount of water that leaves the soil profile by on the one hand and evaporation and transpiration on the other hand also shows an annual cycle this time variable response due to climatic forcing is furthermore visible in the multimodal nature of the site specific master transit time distribution representing the flow averaged probability density for rainwater to become recharge the spatial variability of travel times is mainly driven by soil texture and structure with significant longer travel times for the clayey stagnosols than for the loamy to sandy cambisols and arenosols

effects of land use changes on badland erosion in clayey drainage basins radicofani central italy abstract hillslopes of the radicofani area in the upper valley of the orcia river southern tuscany region italy consist mainly of early pliocene clayey sediments and are widely affected by frequent badland erosion reforestation with frugal conifers has been carried out in the area over the last 50 years the goal of the present study is to evaluate the impact of reforestation and land use change on erosion rates in nine small drainage basins through a multidisciplinary approach geological geomorphological hydrological and land use characteristics were analyzed by a diachronic confrontation between pre reforestation 1954 and post reforestation 2007 situations aerial photo interpretation and processing in gis allowed us to quantify changes in areas affected by badland erosion land use and variations in erosion rates moreover dendrometric data were gathered from 18 circular sample plots in forest stands of 40 years old this allowed us to evaluate both the adaptability of different forest species to the clayey substrate and reforestation fragmentation the differences between the pre and post reforestation situations led to increases in arable land and forest areas and considerable decreases in erosion rates and badland areas however no significant correlation between the erosion rates and the forest area emerged due to the excessive fragmentation of reforestation cores and relatively small reforested surfaces land reclamation seems to have played a more important role in reducing erosion in the clayey substrate the integrated method presented here is an important tool useful to understand the morphological dynamics of badlands in relation to forest vegetation and for land planning and management

detachment and infiltration variations as consequence of regolith development in a pyrenean badland system the araguas experimental catchment has been monitored to study badland dynamics in the central pyrenees previous studies of weathering processes within the catchment reported strong regolith dynamics associated with seasonal variations in the temperature and moisture regimes a preliminary analysis of hydrological response and suspended sediment transport data recorded at a gauging station also demonstrated seasonal trends the main objective of the present study is to understand the effect of regolith dynamics on sediment detachment and infiltration processes based on field studies using simulated rainfall the experiment design was based on seasonal differences in the physical conditions of surface regolith and the general trends of hydro sedimentological responses rainfall simulations were conducted on small plots using a pressure nozzle similar experimental rainfall conditions were set for all plots rainfall intensity around 45 mm h 1 the results showed strong variations in the infiltration and detachment responses closely associated with the regolith conditions and crusting development infiltration showed seasonal differences in time lag and intensity average infiltration rates ranged from very low 2 05 mm h 1 to moderated high values 44 04 mm h 1 associated to regolith development conditions maximum sediment concentration as an indicator of particles produced by detachment also ranged from moderate 3 g l 1 to extreme values 145 g l 1 mean and minimum infiltration rates showed negative correlations with initial moisture content sediment concentration showed a positive correlation with time lag ponding and sealing time and a negative correlation with initial moisture in terms of seasonal trends infiltration and erosion responses were relatively stable during spring and autumn whereas wide variations were recorded in infiltration rates and sediment detachment during summer and winter as a general conclusion the obtained results indicate that seasonal differences in detachment and infiltration depend on the nature of regolith development copyright 2009 john wiley sons ltd

badland dynamics in the central pyrenees temporal and spatial patterns of weathering processes the genesis and development of badlands is controlled by bedrock lithology topography and climate the development of badlands in the central spanish pyrenees is favoured by the presence of marls and a climate with a marked seasonality the combination of these factors results in active hydrosedimentological processes the aim of the present work was to study the dynamics of badlands in the central pyrenees with a focus on the temporal and spatial patterns of the dominant weathering processes the study area was a small mountain catchment and we focussed on the continuous observation of a number of physical parameters that control regolith development and weathering processes samples collected from different depths at sites with different aspects enabled temporal comparisons of the factors involved in the development of surface regolith that can be considered as indicators of the weathering of the marls these indicators were then related to environmental variables moisture and temperature atterberg limits were established and related to moisture content to explain slope dynamics and related processes finally analyses of carbonate content were performed in the laboratory the results validate the employed methodology supporting our description of weathering processes the established chronological sequence and the relation of these processes to climatic and topographic parameters the results obtained since january 2004 show that the chosen indicators are sensitive to seasonal dynamics variations in temperature and water supply and slope aspect the development and dynamics of regolith on north facing slopes is more active than that on south facing slopes freeze thaw is the main weathering process on north facing slopes while south facing slopes are dominated by the development of crusts associated with wetting drying processes washing effects and lower temperatures upon north facing slopes mean that the dissolution of carbonates is more pronounced in such areas compared with south facing slopes especially within the upper layers of the regolith copyright 2006 john wiley sons ltd

vertic features in a soil catena developed on eocene marls in the inner depression of the central spanish pyrenees scientific interest in marls has expanded in recent years especially in regard to erosion rates weathering processes and stabilization of the resulting sediments however information regarding the properties and evolution of overlying soil is relatively scarce this work analyzes the relationship between mechanical properties and standard properties of soils developed on eocene marls in mountainous regions of the southern central spanish pyrenees it also examines whether these soils have the vertic features traditionally ascribed to them and how these features may vary along a catena the water holding capacity of the soils exhibits a typical catena related trend that increases progressively from low values in upper slope profiles to higher values for the middle slope and valley the soils have a high percentage of silt sized particles quartz and calcite are the main mineralogical components of the fine earth fraction illite represents the major component of the clay fraction the linear extensibility and atterberg limits are positively and significantly correlated to clay content low liquid limit usually less than 30 low soil aggregate stability lower than 25 in ap horizons and high subsidence values n 0 7 are likely factors in the high dispersivity and sliding risk observed for the soils these factors also explain the presence of buried soils and lithological discontinuities in lower slope profiles as well as the relatively limited degree of soil evolution despite a relatively humid climate low porosity mainly of vesicular type and a poor structure facilitate saturation in the wet season and lead to soil reduction processes especially within deep soil horizons along lower parts of hillslopes simulated wetting and freezing treatments were shown to fracture the unaltered marls into small fragments demonstrating the soil s susceptibility to physical weathering given moderate clay content absence of smectites and moderate soil extensibility cole 0 06 cm cm 1 in most horizons topsoil cracking in lower slope profiles is apparently caused by high rates of evaporation during the dry season the soils described here did not meet the requirements of vertic horizons but most meet the diagnostic criteria of having a protovertic horizon despite the absence of swelling and shrinking clays

two subevents across the japan trench during the 7 december 2012 off tohoku earthquake mw 7 3 inferred from offshore tsunami records a tsunamigenic earthquake with a moment magnitude of 7 3 occurred near the japan trench off tohoku northeast japan on 7 december 2012 operational seismic monitoring inferred that the earthquake was composed of doublet sources of comparable magnitudes the first event was reverse faulting and the second event which occurred 10 20 s later was normal faulting an associated tsunami was observed at offshore stations having an amplitude of 10 1 to 101 cm inverse modeling using the observed tsunami records reveals possible vertical seafloor deformations we can then constrain in terms of the source location that the tsunamigenic earthquake involves two subfaults across the japan trench one is the outer trench reverse faulting as the first event and the second is the inner trench normal faulting the present study shows that tsunami analysis with seismograph analyses effectively constrains the epicenter locations even in the case of complex earthquakes like doublets

linear and nonlinear computations of the 1992 nicaragua earthquake tsunami numerical computations of tsunamis are made for the 1992 nicaragua earthquake using different governing equations bottom frictional values and bathymetry data the results are compared with each other as well as with the observations both tide gauge records and runup heights comparison of the observed and computed tsunami waveforms indicates that the use of detailed bathymetry data with a small grid size is more effective than to include nonlinear terms in tsunami computation linear computation overestimates the amplitude for the later phase than the first arrival particularly when the amplitude becomes large the computed amplitudes along the coast from nonlinear computation are much smaller than the observed tsunami runup heights the average ratio or the amplification factor is estimated to be 3 in the present case when the grid size of 1 minute is used the factor however may depend on the grid size for the computation

relationships between suspended sediment concentrations and discharge in two small research basins in a mountainous mediterranean area vallcebre eastern pyrenees abstract the relationships between suspended sediment concentrations and discharge were studied at the can vila 0 56 km2 and ca l isard 1 32 km2 sub basins of the vallcebre research area eastern pyrenees during a period of 5 years that included 67 events of diverse magnitude abandoned agricultural fields and forests are the main land use in the can vila basin whereas the ca l isard basin is mainly forested though there are also some heavily eroded landscapes badlands the most frequent events were of a single discharge peak although double and multiple peaked events were also recorded clockwise positive hysteretic loops occurred in both catchments mainly during the wet seasons when precipitation was of moderate intensity average of 18 mm h 1 and baseflow before the event was rather high average for ca l isard 8 1 l s 1 km 2 and for can vila 11 76 l s 1 km 2 the bulk of stream discharge came from saturated areas whereas sediments came mainly from the stream channels counter clockwise negative hysteretic loops were much more frequent in the ca l isard basin mainly in summer when rainfall intensity was high average of 32 5 mm h 1 and baseflow was low average for ca l isard 0 94 l s 1 km 2 and for can vila 0 73 l s 1 km 2 most of the water and sediment came from the badlands eight shaped loops occurred in transition periods mainly in the ca l isard basin

deep sea observations and modeling of the 2004 sumatra tsunami in drake passage 1 the 2004 sumatra tsunami was clearly recorded by two uk bottom pressure gauges dpn and dps deployed in drake passage between south america and antarctica these open ocean records were examined to estimate characteristics of the tsunami waves and to compare the results of numerical simulations with the observations maximum wave heights measured at these gauges were 4 9 cm at dpn and 7 4 cm at dps the travel times from the source area were 19 h 46 min and 19 h 39 min respectively consistent with the times obtained from the nearby coastal tide gauges the numerical model described well the frequency content amplitudes and general structure of the observed waves with only small time shifts probably related to wave dispersion effects the shifts were 15 min for dpn and 10 min for dps with the modeled waves leading the observations in each case further inspection of the simulated and observed records revealed that the identified tsunami waves are related to the second main train of waves propagating by the energy conserving route along the mid ocean ridges while the first train of waves travelling by the fastest route across the ocean remained unrecognizable in the observed dps and dpn records and undetectable in the records of coastal tide gauges because of their insignificant amplitudes compared to the background variability

lithological properties and weathering response on badland hillslopes rills and rill networks are important geomorphological features in clay rich badland areas rill network geometry varies with climate and topography but the lithological properties are also critical rill systems on mudrock and sandstone in alberta badlands were studied to examine progressive changes in material properties as smectite rich mudrocks and sandstones undergo weathering and the impact of seasonal changes in precipitation patterns three plots with well developed rill systems on each unit were examined in may 2001 and 2003 geometric properties were determined along a dense grid and surface and subsurface samples were analyzed for texture crust structure sem mineralogical composition xrd content of major elements xrf aggregate stability and moisture content the rill width depth ratio decreased from 2001 to 2003 on mudrock rill networks the popcorn crust found in 2001 changed to a thin dense crust in 2003 2001 materials had higher na and ca concentrations and the 2003 materials have higher al k concentrations unweathered mudrock shards were subjected to incremental weathering in controlled laboratory conditions depending on moisture input different crust types developed on materials after 10 wetting drying cycles material responded to different amounts of precipitation by alteration from swelling to dispersion

the october 28 2012 mw 7 8 haida gwaii underthrusting earthquake and tsunami slip partitioning along the queen charlotte fault transpressional plate boundary the pacific north american plate boundary is undergoing predominantly right lateral strike slip motion along the queen charlotte and fairweather transform faults the queen charlotte fault qcf hosted the largest historical earthquake in canada the 1949 m s 8 1 strike slip earthquake which ruptured from offshore northern haida gwaii several hundred kilometers northwestward on january 5 2013 an m w 7 5 strike slip faulting event occurred near the northern end of the 1949 rupture zone along central and southern haida gwaii the relative plate motion has 20 oblique convergence across the left stepping plate boundary there had been uncertainty in how the compressional component of plate motion is accommodated the october 28 2012 m w 7 8 haida gwaii earthquake involved slightly 20 oblique thrust faulting on a shallow 18 5 northeast dipping fault plane with strike 320 parallel to the qcf consistent with prior inferences of pacific plate underthrusting beneath haida gwaii the rupture extended to shallow depth offshore of moresby island beneath a 25 30 km wide terrace of sediments that has accumulated in a wedge seaward of the qcf the shallow thrusting caused seafloor uplift that generated substantial localized tsunami run up and a modest far field tsunami that spread across the northern pacific prompting a tsunami warning beach closure and coastal evacuation in hawaii although ultimately tide gauges showed less than 0 8 m of water level increase the mainshock rupture appears to have spread with a 2 3 km s rupture velocity over a length of 150 km with slip averaging 3 3 m concentrated beneath the sedimentary wedge the event was followed by a substantial aftershock sequence in which almost all of the larger events involve distributed intraplate normal faulting extending 50 km oceanward from the qcf the highly oblique slip partitioning in southern haida gwaii is distinctive in that the local plate boundary parallel motion on the qcf may be accommodated either by infrequent large strike slip ruptures or by aseismic creep as seems to be the case for deeper oblique relative plate motion beneath haida gwaii while the sedimentary terrace accumulates plate boundary perpendicular compressional strain that releases in almost pure thrust faulting earthquakes seaward of the qcf

the groundwater resources and sustainable yield of cheju volcanic island korea hydrogeologic data of 455 water wells comprising geologic logs water qualities and aquifer test results are analyzed to determine hydrogeological characteristics water quality and sustainable yield of the groundwater resources of cheju volcanic island the groundwater of the island occurs in unconsolidated pyroclastic deposits and clinkers interbedded in highly jointed basaltic and andesitic rocks as high level basal and parabasal groundwater under unconfined conditions the total storage of groundwater is estimated at about 44 billion m3 the average transmissivity and specific yield of the aquifer are at about 0 34 m2 s 1 29300 m2 day 1 and 0 12 respectively the average annual precipitation is about 3 39 billion m3 of which 1 49 billion m3 equivalent to 44 0 of the total annual precipitation is recharged into aquifers with 0 638 billion m3 year 1 of runoff and 1 26 billion m3 year 1 of evapotranspiration based on a groundwater budget analysis the sustainable yield is estimated at about 0 62 billion m3 year 1 equivalent to 41 6 of annual recharge a low permeability marine sedimentary formation sehwari formation composed of loosely cemented sandy silt was recently found to be situated at 120 68 m below mean sea level if the said marine sediment is distributed as a basal formation of the freshwater zone of the island most of its groundwater will be of parabasal type so the marine sediment is one of the most important hydrogeological boundaries and groundwater occurrences in the area

understanding groundwater systems and their functioning through the study of stable water isotopes in a hard rock aquifer maheshwaram watershed india summary groundwater degradation through abstraction contamination etc shows a world wide increase and has been of growing concern for the past decades in this light the stable isotopes of the water molecule 18 o and 2 h from a hard rock aquifer in the maheshwaram watershed andhra pradesh india were studied this small watershed 53 km 2 underlain by granite is endorheic and representative of agricultural land use in india with more than 700 bore wells in use in such a watershed the effect of overpumping can be severe and the environmental effects of water abstraction and contamination are of vital importance a detailed and dynamic understanding of groundwater sources and flow paths in this watershed thus is a major issue for both researchers and water managers especially with regards to water quality as well as the delimitation of resources and long term sustainability to this end the input from monsoon precipitation was monitored over two cycles as well as measuring spatial and temporal variations in 18 o and 2 h in the groundwater and in precipitation individual recharge from the two monsoon periods was identified leading to identification of periods during which evaporation affects groundwater quality through a higher concentration of salts and stable isotopes in the return flow such evaporation is further affected by land use rice paddies having the strongest evapotranspiration

source of the july 2006 west java tsunami estimated from tide gauge records 1 the source of the west java tsunami of july 17 2006 which was generated during a large earthquake near the sunda trench is constrained by tsunami waveforms that were recorded on six tide gauges around the indian ocean the tsunami travel times poorly constrain the source area probably because shallow bathymetry near these gauges is not well known inversion of tsunami waveforms however reveals that the tsunami source was about 200 km long the largest slip about 2 5 m for instantaneous rupture model was located about 150 km east of the epicenter most of the slip occurred on shallow parts of the fault indicating that this earthquake shares the same characteristics with tsunami earthquakes which generate abnormally large tsunamis compared with ground shaking the slip distribution yields a total seismic moment of 7 0 1020 nm mw 7 8

soil genesis and evolution on calanchi badland like landform of central italy abstract calanchi are badland like erosional landforms common in the mediterranean region which form from accelerated erosion processes the calanchi slopes naked or differently vegetated can be considered as formed by different ecological tesserae originated by the mutual interaction of several factors such as erosion geomorphology microclimatic conditions vegetation ground cover and pedogenesis however information about pedogenesis is rather scarce mainly because the soils developing on calanchi slopes are incessantly disturbed by erosion processes to understand the role of soil evolution on landslide erosion we considered three land facets each one made up of four tesserae t1 to t4 which represented the different steps of soil and vegetal evolution of calanchi the soil of each tessera was described sampled by genetic horizons and the samples were characterized for their physical mineralogical and chemical properties field observations and laboratory data suggest that pedogenesis in the calanchi badlands may progress until a critical threshold indeed advanced plant colonization and solum development improve soil structure increase soil organic matter and favor redistribution of nutrients along the profile the improvement of structure at depth fosters water storage and clay dispersion through soil leaching and reduction of ionic strength of the soil solution making soil less stable depending on the slope gradient the soil weight acquired during rainfall events may trigger landsliding mudflows or collapses that rejuvenate the surface

geomorphic agents versus vegetation spreading as causes of badland occurrence in a mediterranean subhumid mountainous area abstract previous evidence on the chief role of physical weathering on badland development in the vallcebre area south eastern pyrenees led to the study of the amounts of energy available for the main geomorphic agents and to analyze the results in the light of the patterns of vegetation cover and species distribution in order to explain both the occurrence of these badland forms and their preference for north facing shady hillslopes results showed that the weathering potential provided by freezing is about two orders of magnitude greater than rainfall kinetic energy and that the former strongly depends on hillslope aspect the study of vegetation demonstrated that vegetation is poorer in cover and species composition on shady hillslopes than on sunny ones spontaneous revegetation of these surfaces being restrained by cold thermal conditions rather than by water availability these results show that the occurrence of these badland areas depends on montane climatic attributes that control geomorphic and biological processes and that are different from those that promote the occurrence of badlands in dry mediterranean areas the preference for northern aspects provides evidence for these differences

numerical tsunami simulation including elastic loading and seawater density stratification systemic discrepancies between observed and modeled tsunami wave speeds were previously identified for two recent major tsunamis the 2010 maule and 2011 tohoku events to account for these discrepancies we developed a numerical tsunami propagation code solving the shallow water equation and including the effects of elastic loading of the seafloor by the tsunami as well as a linear density profile in the seawater column we show here that both effects are important to explain the commonly observed difference between observations and simulations we conclude that the density variation in the seawater column affects the wave speed without changing the waveform whereas the loading effect has an effect on the wave speed and the waveform showing a negative phase before the main arrival due to the depression of the seafloor surrounding the tsunami wave the combination of both effects is needed to achieve a better match between observations and simulations

the sediment budget of a highly dynamic mesoscale catchment the river isabena the paper presents the sediment budget of the isabena basin a highly dynamic 445 km2 catchment located in the central pyrenees that is patched by highly erodible areas i e badlands the budget for the period 2007 2009 is constructed following a methodology that allows the interpolation of intermittent measurements of suspended sediment concentrations and enables a subsequent calculation of sediment loads data allow specification of the contribution of each subbasin to the water and sediment yield in the catchment outlet mean annual sediment load was 235 000 t y 1 specific sediment yield reached 2000 t km 2 y 1 a value that indicates very high sedimentary activity especially in the case of villacarli and lascuarre subcatchments were most badlands are located the specific sediment yield obtained for the entire isabena is 527 t km 2 y 1 a high value for such a mesoscale basin results show that a small part of the area i e 1 controls most of the catchment s gross sediment contribution sediment delivery ratio ratio between sediment input from primary sources and basin export has been estimated at around 90 while in channel storage represents the 5 of the annual load on average the high connectivity between sediment sources i e badlands and transfer paths i e streamcourses exacerbates the influence of the local sediment production on the catchment s sediment yield a quite unusual fact for a basin of this scale

relationships between a new slope morphometric index and calanchi erosion in northern sicily italy the italian badlands or calanchi are common landforms in mediterranean areas including central and southern italy calanchi landforms may be compared to small hydrographic basins these landforms are characterised by dense hierarchical and rapidly evolving drainage systems carved into steep clayey slopes and by a sharply alternating pattern of furrows and narrow generally sharp crests this work presents a study of morphometric characteristics and a statistical analysis for two sites in northern sicily italy on outcrops of silty clay deposits affected by active erosion processes which give this area a typical calanchi landscape in particular factors closely linked to the characteristics of the hydrographic network and slope morphometry were considered and analysed the initial geometry of the slopes was reconstructed and statistically compared with that of the current calanchi slopes including the drainage network a new morphometric index morphometric slope index msi was defined to represent the initial slope geometry as a whole this index was found to be effective in defining the structure of hydrographic networks summarising the characteristics and type of slope evolution and quantifying the rate of soil erosion the rate was determined based on both linear gully erosion and areal landslides sheet and rill erosion morphogenetic processes and our analysis based on msi indicates the dominance of areal erosion msi could also be used for basins larger than calanchi to represent the characteristics of geomorphic processes

using h and o isotopic data for estimating the relative contributions of rainy and dry season precipitation to groundwater example from cheju island korea abstract a comparison of deuterium excess or d values of precipitation and groundwater at cheju island korea indicates that unlike in many temperate climates precipitation during the whole year contributes to groundwater recharge this in turn suggests that evapotranspiration effects are minimal consistent with the fact that the island contains highly permeable volcanic rocks overlain by thin soils this hypothesis is contrary to current water budget models that ascribe a significant role to evapotranspiration processes three coastal springs and several streams and ponds throughout the island have enriched 18 o and d values that plot off the local meteoric water line and have relatively high cl concentrations this relationship is suggestive of seawater mixing for the coastal springs and evaporation for the streams and ponds this database thus provides a useful means for evaluation of groundwater resources of the island

traveltime delay and initial phase reversal of distant tsunamis coupled with the self gravitating elastic earth systematic tsunami traveltime delays of up to 15 min relative to the numerically simulated long waves from the 2010 chilean and 2011 tohoku oki earthquakes were widely observed at deep ocean tsunamimeters enigmatic small negative phases appearing before the main peak were commonly found only at the trans oceanic locations the frequency dependence of the measured tsunami phase velocities shows reverse dispersions at long periods i e the tsunami speed becomes slower at periods beyond 1000 s this is consistent with the phase velocities of a tsunami mode coupled with a self gravitating elastic earth suggesting that the effects of compression and dilatation of seawater elastic tsunami loadings on a solid earth and the geopotential variations associated with the motion of mass during tsunami propagation are responsible for the traveltime delays and the initial negative phases simple 1 d tsunami propagation tests confirm that the reverse dispersion creates a small negative phase that precedes the main peak at large distances a new method to simulate tsunami waveforms on real ocean bathymetry that takes into account seawater compressibility the elasticity of the earth and geopotential perturbations has been developed by applying a phase correction to the simulated long waves the simulated waveforms in which phase corrections are applied for the dispersion effects accurately reproduce the observed waveforms including a small initial negative phase that appears at distant locations the traveltime difference between the observed and simulated waveforms has been decreased to less than 5 min and the waveform difference between them remarkably diminishes

did a submarine landslide contribute to the 2011 tohoku tsunami many studies have modeled the tohoku tsunami of march 11 2011 as being due entirely to slip on an earthquake fault but the following discrepancies suggest that further research is warranted 1 published models of tsunami propagation and coastal impact underpredict the observed runup heights of up to 40 m measured along the coast of the sanriku district in the northeast part of honshu island 2 published models cannot reproduce the timing and high frequency content of tsunami waves recorded at three nearshore buoys off sanriku nor the timing and dispersion properties of the waveforms at offshore dart buoy 21418 3 the rupture centroids obtained by tsunami inversions are biased about 60 km nne of that obtained by the global cmt project based on an analysis of seismic and geodetic data together with recorded tsunami waveforms we propose that while the primary source of the tsunami was the vertical displacement of the seafloor due to the earthquake an additional tsunami source is also required we infer the location of the proposed additional source based on an analysis of the travel times of higher frequency tsunami waves observed at nearshore buoys we further propose that the most likely additional tsunami source was a submarine mass failure smf i e a submarine landslide a comparison of pre and post tsunami bathymetric surveys reveals tens of meters of vertical seafloor movement at the proposed smf location and a slope stability analysis confirms that the horizontal acceleration from the earthquake was sufficient to trigger an smf forward modeling of the tsunami generated by a combination of the earthquake and the smf reproduces the recorded on near and offshore tsunami observations well particularly the high frequency component of the tsunami waves off sanriku which were not well simulated by previous models the conclusion that a significant part of the 2011 tohoku tsunami was generated by an smf source has important implications for estimates of tsunami hazard in the tohoku region as well as in other tectonically similar regions

tsunami waveform inversion for sea surface displacement following the 2011 tohoku earthquake importance of dispersion and source kinematics this paper considers the importance of model parameterization including dispersion source kinematics and source discretization in tsunami source inversion we implement single and multiple time window methods for dispersive and nondispersive wave propagation to estimate source models for the tsunami generated by the 2011 tohoku oki earthquake our source model is described by sea surface displacement instead of fault slip since sea surface displacement accounts for various tsunami generation mechanisms in addition to fault slip the results show that tsunami source models can strongly depend on such model choices particularly when high quality open ocean tsunami waveform data are available we carry out several synthetic inversion tests to validate the method and assess the impact of parameterization including dispersion and variable rupture velocity in data predictions on the inversion results although each of these effects has been considered separately in previous studies we show that it is important to consider them together in order to obtain more meaningful inversion results our results suggest that the discretization of the source the use of dispersive waves and accounting for source kinematics are all important factors in tsunami source inversion of large events such as the tohoku oki earthquake particularly when an extensive set of high quality tsunami waveform recordings are available for the tohoku event a dispersive model with variable rupture velocity results in a profound improvement in waveform fits that justify the higher source complexity and provide a more realistic source model

mapping badland areas using landsat tm etm satellite imagery and morphological data abstract soil erosion is the most influential component of land degradation for its strong impacts on both natural and agricultural environments in order to support effective intervention and recovery policies for eroded areas monitoring techniques should take into account the space time variability of the processes involved and make use of assessed mapping methodologies as baseline criteria for studying the dynamics of landform development when using multispectral data for mapping eroded areas low spectral separability is a significant limit in areas with complex features where soil materials are frequently remixed by surface runoff since multispectral satellite images are a valuable data source for multi temporal analyses of erosion processes at the medium scale we assessed how accurately a badland area can be identified from landsat tm and etm data a protocol for an optimal mapping was built up by testing the performance of different supervised algorithms and input layers spectral and morphological tests were carried out in a well known badland area of basilicata italy with an extension of 8000 ha results obtained from the use of spectral bands with and without thermal channel and principal components returned an overall accuracy ranging from 53 for classification on first three components to 72 for classification on all bands from tm with low values for the kappa coefficient 0 30 0 50 showing that the spectral information alone are insufficient to accurately identify badland areas in order to improve mapping we found that the integration of slopes and aspects derived from a digital elevation model dem can overcome problems inherent to the low separability of spectral signatures the use of morphological data was tested for different classification algorithms and integration approaches in discriminating badlands the better performing algorithm was mlc maximum likelihood classifier and the best results were obtained by integrating all seven bands including tir with slope and aspect maps as input within the classifier a 0 85 and k 0 75 for both the sensors we selected such parameters because they play an important role in characterising badlands of study area from a morphological perspective but the proposed approach is also conceptually simple and can be easily exported to other areas the obtained results support the hypothesis that the combined use of remote sensing imagery and auxiliary morphological data significantly improves the mapping of badlands over large areas with heterogeneous features thus providing a useful methodology for long term studies on soil erosion processes

temporal distribution of suspended sediment transport in a humid mediterranean badland area the araguas catchment central pyrenees abstract this paper analyses the temporal patterns of suspended sediment yield in the araguas catchment central spanish pyrenees a small experimental catchment with extensive badlands the catchment has been monitored since 2004 to study weathering erosion and hydrological and sediment responses to understand the superficial dynamics of a badland area in a relatively humid environment the development of badlands in the central spanish pyrenees is favoured by the presence of marls and a markedly seasonal climate the continuous observation of selected physical parameters and environmental variables enables us to establish seasonal patterns of weathering processes and identify those factors that control regolith development freeze thaw cycles in winter and wetting drying in spring summer are the main processes involved in regolith weathering thereby controlling slope development in combination with rainfall related erosion processes the 64 floods recorded during the study period december 2005 to january 2007 were used for a hydrosedimentological analysis the main observed features indicate that the araguas catchment reacts to all rainfall events resulting in steep rising and recession limbs on the hydrograph and a very short time lag floods show high suspended sediment concentrations and a heterogeneous temporal distribution related to seasonal variations in surface runoff production these differences increase the degree of complexity involved in studying sediment response suspended sediment concentration and transport mainly depend on rainfall volume maximum rainfall intensity peak flow and runoff occurrence finally the similarities among the obtained hydrographs sedigraphs and hyetographs in combination with the rapid response of most of the floods suggest a large contribution of overland flow derived mainly from infiltration excess runoff upon badland areas accordingly the significant correlations obtained between rainfall intensity and sediment concentration mainly during the dry season which suggest a single source area for both runoff and sediment also support the hypothesis of hortonian hydrological response within badland areas

lithology controls the regional distribution and morphological diversity of montane mediterranean badlands in the upper llobregat basin eastern pyrenees abstract badlands are pervasive in a wide range of environmental conditions across the mediterranean region including arid semiarid and humid environments on montane cold subhumid and humid mediterranean landscapes harsh thermal conditions on north facing hillslopes favour intense bedrock weathering by freezing and impose serious constraints on plant colonization the above are the customary arguments to explain the high abundance of montane badlands on north exposed shady aspects we studied the distribution and morphological diversity of badlands in the upper llobregat basin catalan pyrenees ne spain using remote sensing information high resolution orthophotos and complementary landsat 8 imagery digital elevation data and regional information on lithology badlands extend over about 200 ha in the upper llobregat basin and occur on two different parent materials swelling smectite rich continental garumnian lutites of late cretaceous age and nonswelling illitic marine eocene marls vegetation assessed by remote sensed vegetation greenness is less developed on north facing badland slopes however badland slope aspect distribution varies considerably with lithology while badlands on eocene marls show preferential distribution on north facing shady slopes badland occurrence on garumnian lutites does not reveal clear slope aspect anisotropy patterns lithology also affects slope gradient with badlands on eocene marls showing rougher topography 30 40 average slope angle than on garumnian lutites 20 30 badland morphological differences induced by lithology are discussed in terms of the greater weathering susceptibility and slope instability of the swelling smectite rich garumnian lutites than of the nonswelling eocene marls elevation which broadly controls annual precipitation and winter air temperature within the region shows no clear influence on badland distribution overall our results reveal lithology as the main factor controlling badland distribution and morphological diversity under the montane mediterranean conditions of the upper llobregat basin

tsunami waveform inversion including dispersive waves the 2004 earthquake off kii peninsula japan 1 long waves are often assumed to model tsunamis but the wavelength of the initial water height distribution produced by a large submarine earthquake particularly in the direction perpendicular to the fault strike is sometimes not much greater than the water depth the resulting tsunami may have a dispersive character that cannot be simulated based on a conventional long wave approximation the 2004 earthquake off kii peninsula m 7 4 on the southern coast of japan indeed produced a dispersive tsunami that was recorded at two stations located off shikoku for the foreshock m 7 1 on the contrary a dominant dispersive tsunami was not recognized at these stations because dispersive waves show strong directional dependence with respect to the fault strike the above difference indicates that the strikes of the main shock and the foreshock were different we conducted a tsunami waveform inversion analysis based on the dispersive tsunami equations to estimate the initial water height distribution of the main shock the estimated initial water height distribution overlapped with the aftershock region suggesting that the fault strike was perpendicular to the trough axis and the total displaced water volume was 1 7 2 0 109 m3 when we used the conventional long wave approximation the estimated initial water height distribution extended considerably from the aftershock area because artificial sources were needed outside the aftershock area to reproduce the observed dispersive waves

analysis of water movement through an unsaturated soil zone in jeju island korea using stable oxygen and hydrogen isotopes summary in order to analyze water movement through an unsaturated soil zone in jeju island korea temporal variations in the oxygen 18 and deuterium isotopes of precipitation and soil waters at three different depths were monitored for about one year the stable oxygen and hydrogen isotopic compositions of the soil waters are plotted between or near the two local meteoric water lines for summer and winter precipitation indicating that the soil waters were recharged from the year around precipitation and evaporation was negligible even during hot summer season in the study area mean residence times of the soil waters were then estimated from the 18o d and deuterium excess or d values of the precipitation and soil waters using two well mixed or exponential models em and one exponential piston flow model epm the regression results show that the combination of the exponential piston flow model and the d values of the precipitation and soil waters gives the most reasonable estimation of the mean residence times of the soil waters in the study area it suggests that the deuterium excess or d values can be used as a better parameter than the 18o or d values alone for estimating mean residence times of subsurface waters not only in korea but also in other northeast asian countries the estimated low moisture contents and hydraulic diffusivities of the soils at the three different depths also indicate that the boundary between the upper fine grained soil and the lower coarse grained soil may act as a capillary barrier and the soil waters probably flow slowly through micropores rather than rapidly through macropores in the unsaturated soil zone

mean recharge times and chemical modelling transfers from shallow groundwater to mineralized thermal waters at montrond les bains eastern massif central france summary a re appraisal of interactions between basinal waters and hydrothermal fluids within the silici clastic series of the intracontinental cenozoic forez basin is proposed using major element and isotope geochemistry together with thermodynamic models recharge processes and shallow sedimentary units in the forez basin were compared using major elements and isotopic data 87 sr 86 sr 18 o 2 h 13 c tritium and 14 c for waters sedimentary carbonates and hercynian basement rocks waters derived from late pleistocene to early holocene surface recharge followed by mixing and chemical evolution through percolation into deep groundwater horizons are investigated isotopic ratios and chemical speciation computed for deeper waters from 0 to 200 m depth indicate that mineralised waters were produced by initial surficial dissolution of calcite in calcareous mudstone providing its sr isotopic signature at about 200 m depth na h 3 o cation exchange with clayey sand rich levels provides additional ca na and oh contents for carbonate saturated water na h 3 o cation exchange can not contribute large na hco 3 concentrations geochemical changes such as increasing 13 c dic values observed from 200 to 500 m depth were modelled by addition of thermal water and geogenic co 2 in increasing proportions with depth 500 mbs thermodynamic calculations of mineral proportions indicate water rock interactions with primary minerals in the metamorphic basement and secondary minerals observed in the basin water temperature and its meteoric origin suggest a basin wide recharge system with water rock interaction driven by heat flow rather than through deep crustal fractures

dynamic evolution of badlands in the roglio basin tuscany italy abstract the roglio basin in the relatively arid central tuscany italy is characterised by the presence of 191 badlands that have developed on pliocene fine grained blue clays a morphometric analysis on the badlands has highlighted that these landforms formation and distribution are primarily related to the steepness of the hill flanks which favour runoff and gravitational processes along with favourable aspects typically the southern ones that experience a stronger solar induced daily thermal variation a detailed physico chemical analysis of the clayey material involved has also been carried out with the specific aim of testing whether this plays a role in the various stages of activity shown by the roglio basin badlands the results indicate that there are no significant differences in the physico chemical properties of an active vs an inactive dormant badland observation and field data however indicate that the dynamic of the roglio basin badlands is strongly controlled by the occurrence of earth flows and the velocity of sediment removal at the bottom of the badlands these two processes variously combined at different intensity in relationship to many local factors are likely to be the main responsible for the different stages of activity shown by the roglio basin badlands

a parametric study of tsunamis generated by submarine slides in the ormen lange storegga area off western norway tsunami generation by submarine slides have been a major concern in the risk assessment for the ormen lange gas field off western norway tsunamis are analysed with a numerical model supplemented by an analytical one both models show how slide extensions and slide dynamics influence the tsunamigenic potential for a large region several combinations of slide parameters were tested and the product of initial acceleration and the volume of the slide gave the best correlation with the maximum surface elevation for the near coastal domain

seasonal 18o variations and groundwater recharge for three landscape types in central pennsylvania usa seasonal 18 o variations in precipitation soil water snowmelt spring flow and stream baseflow were analyzed to characterize seasonal dynamics of groundwater recharge in three central pennsylvania catchments the catchments represented three common landscape types valley and ridge shale mahantango creek valley and ridge carbonate buffalo run and appalachian plateau sandstone benner run samples were collected on a biweekly basis from may 18 1999 to may 9 2000 precipitation soil water and baseflow isotopic composition data indicated that a seasonal recharge bias existed for these catchments most recharge occurred in the fall winter and spring months an altitude effect of k0 16 to k0 32 100 m change in elevation was discernible in precipitation soil water and stream baseflow isotopic compositions soils effectively damped seasonal variations of recharge 18 o composition after depths of 1 62 2 85 m the greatest damping of the annual isotopic composition signal occurred in the shallow soil layers 0 15 cm in these and similar landscapes with thick soils the annual isotopic composition signal may be completely damped prior to reaching the stream as baseflow isotopic variations measured in stream baseflow are more likely to be caused by the shallow flowpath water relatively close to the streams baseflow stable isotope variations found on the basins studied suggested that residence times for subsurface waters to reach channels were much longer than the annual seasonal cycle of 18 o in precipitation damping depths were similar for the three different catchments but it is not certain how spatially variable damping depths were within each catchment this information would be useful in determining areas within catchments that contribute to short term isotopic composition fluctuations within streams new water predictive models that determine isotopic damping depth from meteorological soil and vegetation land use data can help develop a better understanding of the variability of recharge and attenuation of contaminants across the landscape q 2004 elsevier b v all rights reserved

how mudrock and soil physical properties influence badland formation at vallcebre pre pyrenees ne spain abstract soils regoliths and their parent materials were investigated in relation to the development of badlands in the pre pyrenees in ne spain on late cretaceous mudrocks under a mountain mediterranean climate whilst all the soils in the area which are developed on mudrocks show a good structure and support a dense plant cover the bare parent materials slake very rapidly giving rise to badlands characterized by high erosion rates several physical chemical mineralogical and micromorphological properties of soils regoliths and related parent materials were analyzed in order to explain their different susceptibility to erosion and to determine which of all these properties are better related to such erosive behaviour only micromorphological and porosity properties were able to explain the erosion susceptibility whilst mineralogical chemical and physico chemical specific surface area properties were not among the aggregate stability tests performed to estimate the relationships of soil components with the susceptibility to erosion the emerson test for macroaggregate evaluation was particularly well suited although no good correlation was found between the emerson test classes and organic matter content we observed that the degree of slaking in organic rich horizons was always lower than in subsurface horizons and regoliths consequently as far as organic rich aggregates are present in the soil surface the influence of water in producing slaking swelling and then erosion will be minimum however when regoliths and rocks are uncovered the influence of water in these particular materials through freeze drying and swell shrinking will give rise to mudrock desintegration leading to accelerated erosion

simulating badland erosion with kineros2 in a small mediterranean mountain basin vallcebre eastern pyrenees abstract the ca l isard catchment 1 32 km 2 a sub basin of the vallcebre experimental catchments yields large amounts of sediments about 580 mg km 2 year 1 that are produced in relatively small but very active eroded areas badlands several lines of evidence suggest that there is a delay between sediment production caused by intense summer rainstorms and sediment transport occasioned by the main floods produced by large precipitation events following wet antecedent conditions first a calibration validation exercise was carried out with sediment yield data obtained using containers provided with slot divisors in a badlands micro catchment 1240 m 2 then the model was applied to the main badlands areas in the ca l isard sub catchment for a 4 year period and the simulated sediment yields were compared with the records at the gauging station the test was performed with the generalized likelihood uncertainty estimation glue approach for assessing the uncertainty associated with model predictions which assumes that many parameter sets can give acceptable simulations the results demonstrated the capacity of kineros2 to simulate badland erosion although it showed limited robustness a clear temporal mismatch between erosion and sediment transport and the relevance of sediment stores in the catchment were confirmed while the total weights of sediment were generally under predicted the limited suitability of the area used for calibration or the role of sediment sources not simulated in the approach may account for this shortcoming

regolith behaviour and physical weathering of clayey mudrock as dependent on seasonal weather conditions in a badland area at vallcebre eastern pyrenees abstract studies on badland areas in the vallcebre basin pyrenees suggest that erosion rates are controlled by the weathering rate of mudrocks to obtain the temporal pattern of physical weathering and its control on the erosive processes monitoring of regolith temperatures at different aspect depth and lithology and periodical determination of regolith moisture and bulk density were carried out changes in surface regolith have also been monitored by means of photographic techniques using an especially designed tripod finally the hydrological and erosive response of the regolith trough the seasons were studied using rainfall simulations the results obtained support and confirm previous knowledge on the role of frost action in mudrock weathering and the role of subsequent regolith development and wetness status on infiltration and runoff generation these seasonal changes of behaviour are so important that they raise serious questions about the validity of observations or experiments carried out in only one season this work confirms that erosion processes are controlled by regolith formation during winter and regolith depletion by storm rainfall erosion during summer spring and early autumn it also raises important points about annual trends of infiltration and erodibility that should be used as guidelines for modelling runoff and sediment production

soil erosion and hydrology of the western mediterranean badlands throughout rainfall simulation experiments a review abstract rainfall simulation experiments are widely used in geomorphological research in badland areas this technique contributed significantly to our understanding of badland geomorphology in the mediterranean belt due to the different types of simulated rainfall applied and the variable size of the plots a review of the state of the art is necessary this study confirmed that rainfall simulations are well suited to i analyse runoff infiltration processes and sediment detachment within badlands and ii to establish the factors determining the hydrological and erosion response at interrill scale in badland areas the hydrological response of badlands is characterized by rapid responses low to moderate infiltration rates ranging from close to 0 to 55 mm h 1 and high runoff coefficients i e 60 positive relationships are observed between antecedent soil moisture content and rainfall intensity on the one hand and runoff coefficients on the other sediment concentration and soil detachment rates are among the highest measured on the mediterranean region i e up to 84 8 g l 1 and 4722 4 g m 2 h 1 results show that rainfall intensity runoff coefficient and slope angle have a positive influence on sediment concentration and sediment detachment in the case of rock fragment cover its influence is variable according to the soil cover percentage rainfall simulations increase our understanding of the temporal and spatial variability of the soil erosion processes however rainfall simulation provides mostly qualitative rather than quantitative information because of the small plot size and the simulated rainfall characteristics due to facility for repeating experiments and recording a high quantity of data in short time however this method allows the comparison amongst different environments and soil conditions as the rainfall properties can be reproduced

sediment budget for subalpine watersheds lake tahoe california usa abstract pinpointing erosional hot spots or sediment source areas within a watershed can be difficult because of the highly non linear and episodic nature of effective runoff and sediment transport continuous monitoring of stream networks can provide insight into sediment source areas not possible from routine sampling by capturing episodic events and integrating entire storm events this paper presents the results of a three year study of spring snowmelt runoff in watersheds of lake tahoe california usa using a network of nine nephelometric turbidometers we estimate that montane badlands comprising 1 2 of the ward creek watershed 25 km 2 contributed 10 39 of snowmelt derived suspended sediment load the badlands are comprised of poorly vegetated and deeply incised gullies formed in parent material of miocene volcanic mudflow breccia the larger 29 5 km 2 blackwood creek watershed also showed high relative erosion rates from volcanic terrain tributaries draining forested granitic and metasedimentary headwater regions had minimal sediment loads monitoring networks indicated that temporary main channel storage regulated release of fine sediment eroded from steep headwater slopes this lag between erosion and delivery may lead to underestimation of gully erosion contribution to sediment budgets

limited overlap between the seismic gap and coseismic slip of the great 2010 chile earthquake the mw 8 8 chile earthquake on 27 february 2010 occurred in a broad region where tectonic loading has been accumulating since the great 1835 earthquake a joint inversion of tsunami and geodetic data suggests that the 2010 earthquake rupture only partly overlapped with the zone of preseismic locking

field survey following the 28 october 2012 haida gwaii tsunami this article documents the near field effects of the largest tsunami of 2012 globally which occurred following canada s second largest recorded earthquake on a thrust fault offshore western haida gwaii on october 28 utc despite a lack of reported damaging waves on the coast of british columbia largest amplitudes were recorded in hawaii three field surveys in the following weeks and months reveal that much of the remote unpopulated uninstrumented coastline of western haida gwaii was impacted by significant tsunami waves that reached up to 13 m above the state of tide runup exceeded 3 m at sites spanning 200 km of the coastline greatest impacts were apparent at the heads of narrow inlets and bays on western moresby island where natural and manmade debris with a clear oceanward origin was found on the forest floor and caught in tree branches inferring flow depths up to 2 5 m bays that see regular exposure to storm waves were generally less affected at these sites a storm origin cannot be ruled out for the debris surveyed logs disturbed from their apparent former footprints on the forest floor at the head of pocket inlet provide evidence of complex runup backwash and oblique flow patterns as noted in other tsunamis discontinuous muddy sediments were found at a few sites sedimentation was not proportional to runup lessons learned from our study of the impacts of the haida gwaii tsunami may prove useful to future post tsunami and paleotsunami surveys as well as tsunami hazard assessments

gypsum scarps and asymmetric fluvial valleys in evaporitic terrains the role of river migration landslides karstification and lithology ebro river ne spain abstract most of the spanish fluvial systems excavated in tertiary evaporitic gypsum formations show asymmetric valleys characterized by a stepped sequence of fluvial terraces on one valley flank and kilometric long and 100 m high prominent river scarp on the opposite side of the valley scarp undermining by the continuous preferential lateral migration of the river channel toward the valley margin leads to vertical to overhanging unstable slopes affected by a large number of slope failures that become the main geological hazard for villages located at the toe of the scarps detailed mapping of the gypsum scarps along the ebro and huerva rivers gypsum scarps demonstrates that landslides and lateral spreading processes are predominant when claystones crop out at the base of the scarp while rockfalls and topples become the dominant movement in those reaches where the rock mass is mainly constituted by evaporites the dissolution of gypsum nodules seasonal swelling and shrinking and dispersion processes contribute to a decrease in the mechanical strength of claystones the existence of dissolution enlarged joints sinkholes and severely damaged buildings at the toe of the scarp from karstic subsidence demonstrates that the interstratal karstification of evaporites becomes a triggering factor in the instability of the rock mass the genesis of asymmetric valleys and river gypsum scarps in the study area seem to be caused by the random migration of the river channel in the absence of lateral tilting related to tectonics or dissolution induced subsidence once the scarp is developed its preservation depends on the physicochemical properties of the substratum the ratio between bedrock erosion and river incision rates and climatic conditions that favour runoff erosion versus dissolution

analysis of the far field tsunamis generated by the 1998 papua new guinea earthquake the tsunami generated by the 1998 papua new guinea earthquake was observed at several tide gauges and ocean bottom pressure gauges in japan the fault model of the 1998 papua new guinea earthquake was estimated using those tsunami waveforms observed in japan and coseismic subsidence observed along the coast of papua new guinea near the source region the numerical simulation of the tsunami using the linear boussinesq equation was carried out the tsunami waveforms in japan are explained by the fault model which is consistent with the harvard cmt solution including the seismic moment of 3 7 1019 nm the additional tsunami source such as a sediment slump is not needed to explain the observed tsunami in japan the mechanism of the earthquake was likely to be a steeply dipping reverse fault the 1998 papua new guinea earthquake was likely to occur within a small accretionary prism near the new guinea trench

observations and numerical modeling of the 2012 haida gwaii tsunami off the coast of british columbia a major mw 7 7 earthquake occurred on october 28 2012 along the queen charlotte fault zone off the west coast of haida gwaii formerly the queen charlotte islands the earthquake was the second strongest instrumentally recorded earthquake in canadian history and generated the largest local tsunami ever recorded on the coast of british columbia a field survey on the pacific side of haida gwaii revealed maximum runup heights of up to 7 6 m at sites sheltered from storm waves and 13 m in a small inlet that is less sheltered from storms leonard and bednarski2014 the tsunami was recorded by tide gauges along the coast of british columbia by open ocean bottom pressure sensors of the neptune facility at ocean networks canada s cabled observatory located seaward of southwestern vancouver island and by several dart stations located in the northeast pacific the tsunami observations in combination with rigorous numerical modeling enabled us to determine the physical properties of this event and to correct the location of the tsunami source with respect to the initial geophysical estimates the initial model results were used to specify sites of particular interest for post tsunami field surveys on the coast of moresby island haida gwaii while field survey observations leonard and bednarski2014 were used in turn to verify the numerical simulations based on the corrected source region

source model of the great 2011 tohoku earthquake estimated from tsunami waveforms and crustal deformation data the slip distribution of the 11 march 2011 tohoku earthquake is inferred from tsunami waveforms gps data and seafloor crustal deformation data the major slip region extends all the way to the trench and the large slip area extends 300 km long and 160 km wide the largest slip of 44 m is located up dip of the hypocenter the large slip amount about 41 m ruptured the plate interface near the trench the seismic moment calculated from the estimated slip distribution is 5 5 10 22 n m mw 9 1 the large tsunami due to the 2011 tohoku earthquake is generated from those large slip areas near the trench the additional uplift at the sedimentary wedge as suggested for the 1896 sanriku earthquake may have occurred during the 2011 tohoku earthquake too

structure and porosity of smectitic mudrocks as affected by experimental wetting drying cycles and freezing thawing cycles abstract the erosion rates in the vallcebre basin pyrenees are controlled predominantly by the physical weathering rate of bare regolith i e mudrocks to obtain information on the influence of thermic and moisture regimes on the weathering dynamics laboratory experiments were carried out to investigate how freezing thawing or wetting drying cycles under controlled conditions affect structure and porosity three different clayey mudrocks were selected to represent materials more susceptible to erosion in the studied area the three lithologies identified as ca1r ca2r carr differed mainly in mineral constituents type and quantity of the clay minerals and cation exchange capacity an automated non contact laser profile meter was used to analyse surface microtopography in order to monitor random roughness variations and to calculate bulk density porosity and pore size distribution were carried out with image analysis freezing thawing cycles were the most active in modifying soil surface and bulk structure roughness of ca1r and ca2r was more than doubled at the end of freezing thawing cycles this variation was mostly associated with the whole surface elevation related to the bulk volume increase roughness variations in carr were less pronounced and related to a modification of the microtopography micromorphological observations revealed a platy structure formation induced by repeated ice lensing also porosity was increased by freezing thawing cycles with the formation of a large number of irregular and rounded pores wetting drying cycles did not affect surface roughness and modified bulk density very little in all samples they increased porosity by the formation of large cracks and fissures overall data from wetting drying cycles showed that changes in water content alone did not produce deep structural modifications a mechanism of alteration of soil structure during freezing thawing cycles is proposed

flood based analysis of high magnitude sediment transport using a non parametric method francke t lopez tarazon j a vericat d bronstert a batalla r j 2008 flood based analysis of high magnitude sediment transport using a non parametric method earth surface processes and landforms 33 13 2064 2077 sponsorship sesam catalan government european social fund

short and long term studies of sediment dynamics in a small humid mountain mediterranean basin with badlands abstract badland landscapes are the main sediment sources in the vallcebre area eastern pyrenees catalonia spain short term studies up to 3 years long carried out between 1980 and 1994 were used to estimate the rates of both denudation on bare surfaces and sediment production at the plot scale to analyse the seasonal dynamics of bedrock weathering and regolith behaviour and to study the relationships between geomorphic activity and herbaceous plant colonisation since 1990 stream flow and suspended sediment loads have been monitored using three gauging stations equipped with infrared backscattering turbidimeters ultra sonic beam attenuation solids sensors and automatic water samplers the combination of the two different approaches has been useful for a better perception of the dynamics of the badland systems and to assess the long term contribution of these areas to the basin sediment loads badland erosion at the event scale for a period of 15 years was simulated with the kineros2 model and allowed the long term comparison between badland erosion and sediment yield at the small basin scale badlands are the main source of sediment in the basin for most of the events but infrequent runoff events cause the removal of sediment stores and the activation of other sediment sources the analysis of the uncertainty of sediment yield measurements for a range of record durations demonstrated that long records are needed for obtaining acceptable results due to the high interannual variability relatively low cost short term geomorphic observations may provide information useful for assessing the long term sediment production in these basins with badland areas only if the observations are used to implement a model able to simulate long term observations

source characteristics of the 2012 haida gwaii earthquake sequence abstract all the significant m l 4 events in the 2012 haida gwaii earthquake sequence are systematically relocated and their moment tensor solutions are determined from waveform inversion the focal mechanism of the mainshock shows low angle thrust faulting along a shallowly dipping plane with a strike parallel to the queen charlotte fault qcf consistent with the inference of pacific plate underthrusting beneath the overriding north american plate the epicenter of the mainshock is located 5 km landward northeast of the surface trace of the qcf suggesting the nucleation of the rupture was near the bottom of the seismogenic locked interface significant aftershocks appear to cluster on the periphery of the main rupture zone with most events located immediately seaward of the deformation front the majority of these events show normal faulting mechanisms that are probably associated with the bending stress within the pacific plate near the deformation front several normal and strike slip events at greater depths within the subducted pacific slab show a consistent pattern of t axis in the down dip direction implying the subducted plate is under a stress regime of down dip extension only a few strike slip events were observed along or near the qcf the limited size and distribution of these events suggest that most of the elastic strain accumulated along the qcf was not released during the 2012 haida gwaii sequence major strike slip earthquakes are likely to occur along the southernmost part of the qcf system in the future

a stable isotope study of recharge processes in the english chalk the 2h and 18o values of water contained in unsaturated chalk have been measured in drillcore profiles taken over a period of 28 months on arable land in cambridgeshire eastern england the isotopic composition of rainfall and lysimeter drainage on the same site has also been monitored over a period of four years the distribution of isotope values in the upper few metres of soil and unsaturated chalk shows that the mechanism of infiltration is not simple piston like downward displacement since the scale of vertical fluctuations is incompatible with estimated annual infiltration and the apparent rates of movement of matrix water derived from thermonuclear tritium studies lysimeter drainage is not isotopically identical to matrix water at the same depth suggesting that different routes to water table are associated with consistently different isotopic content although there is an apparent difference between matrix water beneath arable and permanent grassland these differences appear to cancel out in the composition of bulk recharge beneath these land types the regional aquifer has a uniform isotopic composition similar in value to weighted average rainfall and lysimeter drainage suggesting that the recharge abstraction system has been in isotopic equilibrium for many years despite changes in pumping rates and land use two other chalk sites in southern england have been investigated in less detail but indicate clear difference in infiltration behaviour from that seen in cambridgeshire this seems to be related to a higher matrix conductivity and annual rainfall amount

characteristics of soil water movement in a grass slope in a karst peak cluster region china soil water is very important in hilly areas with thin soil layers and deep groundwater tables such as the karst peak cluster region of southwest china an investigation into soil water movement can provide insights into management of shallow water resources and soil nutrients as well as prevention of groundwater pollution in this study o 18 and h 2 tracers were used to trace soil water movement in planar soil mass type microhabitats in the middle part of a steep hillslope covered by grasses in a karst peak cluster region of china from may 2008 to july 2009 samples of precipitation and two types of soil water which had different integrated degrees of mobility and were of different depth intervals or depths were collected the hydrogeochemical characteristics were compared between precipitation and soil water and these data were applied in convolution based lumped parameter models our results indicated that vertical piston flow rather than lateral flow along the soil bedrock interface played an important role in soil water percolation at least in the upper soil layer approximately 7cm over the permeable bedrock the mixing effect and preferential flow might also play a role in soil water percolation in general the evaporation effect on soil water was weak except for the uppermost 10cm soil matrix water during winter the lower limits of mean transit time of soil matrix flow passing through 5 15 25 35 and 41 5cm depths were 4 81 7 70 16 19 21 85 and 27 44days respectively our study demonstrated the crucial functions of the soil reservoir in regulating the water cycle and could provide guidance on conservation of soil water and hydrological studies the applied method was proved to be a suitable approach for investigating soil water movement on a monthly scale