transmission of wave energy at permeable low crested structures this paper presents a conceptual model for the prediction of energy transmission in presence of emergent permeable low crested structures the transmitted wave is reconstructed from the superposition of perturbations generated leeward the structure by filtration and overtopped volumes the model requires only structure geometry and incident wave conditions wave height period a fair agreement is obtained by comparing the predicted transmission coefficients and wave spectra with measurements performed in wave flume and wave basin

on the role of infiltration and exfiltration in swash zone boundary layer dynamics boundary layer dynamics are investigated using a 2 d numerical model that solves the volume averaged reynolds averaged navier stokes equations with a vof tracking scheme and a k turbulence closure the model is validated with highly resolved data of dam break driven swash flows over gravel impermeable and permeable beds the spatial gradients of the velocity bed shear stress and turbulence intensity terms are investigated with reference to bottom boundary layer bl dynamics numerical results show that the mean vorticity responds to flow divergence convergence at the surface that result from accelerating decelerating portions of the flow bed shear stress and sinking injection of turbulence due to infiltration exfiltration hence the zero up crossing of the vorticity is employed as a proxy of the bl thickness inside the shallow swash zone flows during the uprush phase the bl develops almost instantaneously with bore arrival and fluctuates below the surface due to flow instabilities and related horizontal straining in contrast during the backwash phase the bl grows quasi linearly with less influence of surface induced forces however the infiltration produces a reduction of the maximum excursion and duration of the swash event these effects have important implications for the bl development the numerical results suggest that the bl growth rate deviates rapidly from a quasi linear trend if the infiltration is dominant during the initial backwash phase and the flat plate boundary layer theory may no longer be applicable under these conditions

internal dynamics of a paleoaccretionary wedge insights from combined isotope tectonochronology and sandbox modelling of the south central chilean forearc forearc accretionary wedges are cyclic systems in which material is frontally and or basally accreted material cycling involves underthrusting subduction underplating exhumation erosion transfer to the trench and underthrusting again in this study we present a novel tectonochronologic approach to constrain long term exhumation rates of basally accreted wedge complexes based on isotopic dating of structural features on petrological data and sandbox analogue simulations congruence between the structural inventory in nature and structures generated in scaled sandbox experiments allows detailed insights into wedge dynamics for the present day surface material of the paleoaccretionary wedge of south central chile valdivia area 40 s published u pb ages of detrital zircon place a maximum age of 278 ma for subduction prograde metamorphism at transitional greenschist to blueschist facies conditions 420 c 8 9 kbar was immediately followed by progressive penetrative deformation associated with basal accretion dated at 250 245 ma using rb sr internal mineral isochrons the accretion process involved duplex tectonics and antiformal stacking with formation of near horizontal mylonitic shear zones at around 241 ma continuous basal accretion at depth gave rise to an extensional tectonic regime at higher structural levels both semi ductile small scale extensional shear zones and post kinematic vein mineralizations yield rb sr ages of 235 ma tension gashes representing the latest isotopically dateable stage of structural evolution were formed at 210 ma at conditions of 230 c at 1 5 3 kbar as constrained by fluid inclusion data zircon fission track data indicate final cooling to below 200 c at 186 24 ma the results suggest continuous basal accretion for at least 50 ma with long term average exhumation rates of 0 6 0 2 mm a most probably outbalanced by similar long term average erosion rates changing plate boundary conditions at about 210 200 ma terminated the accretion process as evident from a dramatic decrease of exhumation rates at that time since then the paleoaccretionary wedge remained stably in place despite its delicate geotectonic position within the andean active margin the tectonochronologic approach complements thermochronologic and geomorphologic methods of exhumation research as it provides direct constraints on mass flux rates even for high temperature increments of p t trajectories

an integrated model for the wave induced seabed response around marine structures model verifications and applications abstract in this study an integrated model poro wssi ii for wave seabed structure interactions wssi is developed by combining i the volume averaged reynolds averaged navier stokes varans equations for wave motions in a fluid domain and the porous media flows in porous structures and ii the dynamic biot s equations for a porous elastic seabed the effects of the porous flow in seabed and marine structures and the fluid exchange at the interface between the fluid domain and solid domain on wave characteristics are considered the finite difference two step projection method and the forward time difference method are adopted to solve the varans equations the volume of fluid vof method is applied to track water free surface the finite element method and the generalized newmark method are respectively adopted for the space discretization and time discretization of the dynamic biot s equations a one way integrating method is developed to integrate the varans equations with the dynamic biot s equations several experimental data available in the literature are used to validate the integrated model an overall agreement between the numerical results and the experiment data indicates that the integrated model developed for the wssi problem is highly reliable the integrated model is then applied to investigate the dynamic response of a large scale composite breakwater on a seabed and the mechanism of wssi numerical results indicate that there are intensive fluid exchanges between the water body and the seabed and strong seepage forces in the seabed under the ocean wave loading the excessive upward seepage force leads to the liquefaction of the seabed in the region under wave trough there is a liquefaction zone in the seabed close to the bottom corner of the rubble mound which may lead to foundation instability of the composite breakwater the parametric study indicates that the wave characteristics have a significant impact on the liquefaction properties depth width and area

rans modelling applied to random wave interaction with submerged permeable structures abstract this paper is the second part of the work presented by garcia et al garcia n lara j l losada i j 2004 2 d numerical analysis of near field flow at low crested breakwaters coastal engineering 51 10 991 1020 in the mentioned paper flow conditions at low crested rubble mound breakwaters under regular wave attack were examined using a combination of measured data of free surface bottom pressure and fluid velocities from small scale experiments and numerical results provided by a vof type model cobras based on the reynolds averaged navier stokes rans equations this paper demonstrates the capability of the cobras model to reproduce irregular wave interaction with submerged permeable breakwaters data provided by the numerical model are compared to experimental data of laboratory tests and the main processes of wave structure interaction are examined using both experimental and numerical results the numerical model validation is carried out in two steps first the procedure of irregular wave generation is verified to work properly comparing experimental and numerical data of different cases of irregular wave trains propagating over a flat bottom next the validation of the numerical model for wave interaction with submerged rubble mound breakwaters is performed through the simulation of small scale laboratory tests on different incident wave spectra results show that the numerical model adequately reproduces the main aspects of the interaction of random waves with submerged porous breakwaters especially the spectral energy decay at the structure and the spectrum broadening past the structure the simulations give good results in terms of height envelopes mean level spectral shape root mean square height for both free surface displacement and dynamic pressure inside the breakwater moreover large scale simulations have been conducted on both regular and irregular incident wave conditions the overall pattern of the wave interaction with a large scale submerged breakwater is adequately reproduced by the numerical model the processes of wave reflection shoaling and breaking are correctly captured the good results achieved at a near prototype scale are promising regarding the use of the numerical model for design purposes

petrogenesis of the red mountain pluton laramie anorthosite complex wyoming implications for the origin of a type granite abstract the red mountain pluton the youngest intrusion in the laramie anorthosite complex is one of five monzonitic to granitic a type plutons intruded at 1 43 ga in the laramie mountains of southeastern wyoming the red mountain pluton ranges in composition from fayalite monzonite clinopyroxene quartz monzonite and biotite hornblende quartz syenite to granite the red mountain pluton is petrologically and geochemically distinct from the northern and southern sherman batholith the sybille intrusion and the maloin ranch pluton it has higher feo t feo t mgo and higher k 2 o is more strongly enriched in rees and at any given silica content it has lower abundances of tio 2 feo mgo cao and p 2 o 5 the fayalite monzonite in the red mountain pluton crystallized at temperatures around 1000 c and oxygen fugacities 1 2 log units below that of the fmq buffer similar to the crystallization conditions of the sybille and maloin ranch plutons the biotite hornblende quartz syenite crystallized at oxygen fugacities near or slightly below those of fmq most of the units in the pluton carry mantle like nd sr and pb isotopic compositions similar to the least contaminated anorthositic and ferrodioritic rocks of the lac indicating that the pluton evolved mainly via differentiation substantial crustal assimilation occurred only in the late dikes and the granite we suggest that all of the 1 43 ga a type intrusions in southeastern wyoming are ultimately derived from tholeiites extreme differentiation or partial melting produced monzonitic magmas that have assimilated varying amounts of siliceous crust the differences between the red mountain pluton and other a type granitoids in southeastern wyoming are related to the extent of differentiation prior to crustal assimilation the compositional ranges of a type granitoids in southeastern wyoming suggest that the geochemical spectrum of a type granites worldwide similarly are produced from evolved mantle derived melt that has assimilated varying proportions of crustal material

the modelling of wave action on and in coastal structures description of the wave action on and in coastal structures can lead to a prediction of flow properties and forces on elements of those structures for permeable structures several aspects concerning the interaction between the external flow and the internal flow have to be described accurately to predict for instance velocities and run up levels the p c model odiflocs developed at delft university of technology within the framework of the european mast coastal structures project describes the wave motion on and in several types of structures this structure can be an impermeable or a permeable structure for instance dikes breakwaters and submerged structures can be dealt with the model is a one dimensional model based on long wave equations the program takes various phenomena into account such as reflection permeability infiltration seepage overtopping varying roughness along the slope linear and non linear porous friction darcy and turbulent friction added mass internal set up and the disconnection of the free surface and the phreatic surface satisfactory results were obtained with modelling of run up surface elevations and velocities other applications show more possibilities of the model

spatial distribution of wave overtopping water behind coastal structures spatial distribution of random wave overtopping water behind coastal structures was investigated using a numerical model based on reynolds averaged navier stokes solver rans and volume of fluid vof surface capturing scheme rans vof the computed spatial distributions of wave overtopping water behind the structure agree well with the measurements by pullen et al 2008 for a vertical wall and lykke andersen and burcharth 2006 for a 1 2 sea dike a semi analytical model was derived to relate spatial distribution of wave overtopping water behind coastal structures to landward ground level velocity and layer thickness on the crest this semi analytical model agrees reasonably well with both numerical model results and measurements close to coastal structures our numerical model results suggest that the proportion of wave overtopping water passing a landward location increases with a seaward slope when it is less than 1 3 and decreases with a seaward slope when it gets steeper the proportion of wave overtopping water passing a landward location increases with landward ground level and overtopping discharge it also increases with the product of incident wave height and wavelength but decreases with increasing relative structure freeboard and crest width we also found that the extent of hazard area due to wave overtopping is significantly reduced by using a permeable structure crown findings in this study will enable engineers to establish the extent of hazard zones due to wave overtopping behind coastal structures

mechanics of the scouring and sinking of submerged structures in a mobile bed a physical model study abstract wave induced flow velocity and turbulence may cause scouring in the seabed around coastal structures depending on the wave climate and tidal water depth a 3 d physical modelling study was conducted to investigate the possible causes of the sinking of two submerged coastal structures on the santa maria del mar smm beach spain the experimental investigation was conducted by employing a froude similarity law with a geometric scale of 1 20 and the submerged modular structure was subjected to different wave climates and tidal water levels the combinations of the significant wave height and peak period were chosen from in situ real wave conditions that were monitored during the sinking of the prototype structures linking and unlinking conditions for the modules in the structure were investigated in this study the results show that the modules sank to approximately 48 of their height at the end of the tests with storm waves and semi linking conditions of low water depth most of the experimental results were compatible with the prototype monitoring results tests with proper linking among the modules and tests with an appropriate gravel foundation resulted in a sustainable solution because they presented much less or almost no scouring and sinking

three dimensional numerical simulation on the interaction of solitary waves and porous breakwaters abstract a three dimensional 3d large eddy simulation model with macroscopic model equations of porous flow is proposed to investigate solitary waves interacting with permeable breakwaters the major objective of this paper is twofold first we seek to evaluate the present model through the comparison with available simulated and measured data in the literature the second aim given the 3d nature of flow past a permeable breakwater the variations of permeable breakwater modeled on both macroscopic and microscopic scales are examined first validation is carried out with experiments on solitary wave propagation in a 3d wave basin and then runup on a vertical permeable breakwater with a gap in the lateral direction a satisfactory agreement on the free surface elevation time series is obtained between model and measured results second we replicate the experiments on a solitary wave interaction with a submerged permeable breakwater in a two dimensional narrow wave flume the porous medium is composed of spheres with a uniform size and arranged in a non staggered regular pattern such that the porous medium can thus be modeled on macroscopic and microscopic scales the numerical calculations indicate that the results obtained with macroscopic and microscopic modeling both fit the measurements fairly well in terms of the free surface elevations and velocity fields specifically the microscopic modeling better simulates detailed phenomena such as flow injection from the porous medium and the initial stage of the formation of the main vortex in the leeward face of the obstacle after the solitary wave completely propagates over the permeable object the discrepancies between macroscopic and microscopic model results are insignificant more accurate 3d results are used to determine the trajectories of fluid particles around the porous object to help understand the possible sediment movements in suspensions

diagnostic investigation of impulsive pressures induced by plunging breakers impinging on gravel beaches abstract this paper presents an integrated investigation of physical processes generating impulsive pressures under the action of plunging breakers impinging on gravel beaches this work is an extension of a recent investigation which suggested that wave impacts from plunging breakers acting on gravel beaches may be a key mechanism to enhance sediment mobilisation in particular comparisons of full scale laboratory measurements against model results from a well validated phase depth resolving numerical model based on the reynolds averaged navier stokes rans equations are presented this represents the first attempt at comparison with such a tool against observed hydrodynamics on steep slope 1 8 gravel beaches at prototype scale in order to understand how impulsive pressures are generated under plunging waves the numerical model is used to carry out a detailed investigation to examine the role of each of the acceleration terms in the momentum balance consistent with prior studies numerical results show that under plunging breakers the local acceleration u t alone cannot be used as a proxy for pressure gradients however the contribution of the third term w u z of total acceleration is recognized for the first time and indicates that this term has an important role in both the induced pressure gradient and sediment mobilisation as induced by this particular type of breaking furthermore results suggest that a parameterisation of the pressure gradient in terms of u t u u x may not suffice when dealing with plunging breakers and hence there is a lack of a suitable parameterisation of this process in the present literature thus for different types of breaking it may be necessary to consider a different characterisation of the pressure gradient toward the parameterisation of sediment transport inside the surf zone

numerical analysis of wave loads for coastal structure stability abstract the numerical model cobras uc losada i j lara j l guanche r gonzalez ondina j m 2008 numerical analysis of wave overtopping of rubble mound breakwaters coastal engineering vol 55 1 47 62 is used to carry out a two dimensional analysis of wave induced loads on coastal structures the model calculates pressure forces and moments for two different cross sections corresponding to a low mound and a conventional rubble mound breakwater with a crown wall under regular and irregular incident wave conditions predicted results are compared with experimental information provided in losada et al losada i j lara j l guanche r gonzalez ondina j m 2008 numerical analysis of wave overtopping of rubble mound breakwaters coastal engineering vol 55 1 47 62 and lara et al lara j l losada i j guanche r 2008 wave interaction with low mound breakwaters using a rans model ocean engineering 35 pp 1388 1400 doi 10 1016 j oceaneng 2008 05 006 on a 1 20 scale good agreement is found and the differences between both typologies are explained in detail additionally numerical results are also compared with several semi empirical formulae recommended for design at both the 1 20 model scale and two prototype cross sections results suggest that cobras uc is able to provide realistic stability information that can be used to complete the approach based on currently existing methods and tools

stability analysis of a non conventional breakwater for wave energy conversion abstract this paper presents the stability analysis of a non conventional breakwater cross section integrating an overtopping wave energy converter named obrec the device consists of a traditional rubble mound breakwater in which the upper part of the armour layer is replaced by a smooth ramp and a reservoir the analysis of the structure is carried out by combining model scale experiments and numerical simulations based on the volume averaged reynolds averaged navier stokes varans equations the numerical analysis is used to complete and extend the results of the physical model test campaign providing a deeper understanding of the pressure distribution and resultant force behaviour in locations where laboratory measurements were difficult to obtain or not available results show that the maximum vertical and horizontal total forces on the device are not simultaneous at the time instant of the maximum total horizontal force the vertical force is zero or directed downward due to the significant positive contribution of the force acting on the sloping ramp additional numerical simulations show the influence of the submerged ramp length on the forces acting on the structure using the global and local stability analysis the presence of the shaft contributes positively to the global stability against the sliding failure mode by reducing the uplift force exerted on the horizontal base moreover the stability analysis shows that the critical conditions for the global failure modes occur at different time instants

breaking waves over a mild gravel slope experimental and numerical analysis 1 an experimental and numerical study of the effects of a gravel slope on wave shoaling and breaking is presented herein in the laboratory experiments fluid velocities pressure and water surface elevations were measured experiments were conducted for both spilling and plunging breakers and for gravel slopes with different gravel sizes since gravel slopes caused additional energy dissipation wave heights in the shoaling zone as well as at the breaking point were reduced on the other hand the mean free surface setup inside the surf zone increased it was also observed that the gravel slope had a stronger influence on the vertical profile of undertow under spilling breaker than on that under a plunging breaker moreover the undertow became weaker over a gravel slope with a larger gravel size outside the surf zone turbulent velocities near the gravel slope were relatively high because of the bottom roughness and percolation inside the surf zone turbulence generated by wave breaking dominated over the gravel bed generated turbulence the vertical flow induced by the gravel slope changed the turbulence pattern only at cross sections very close to the shoreline numerical simulations of the wave breaking processes over a gravel slope were performed the numerical model was tested by comparing numerical results with experimental data the model accurately simulated the mean flow quantities the magnitude of turbulence and turbulence characteristics were also simulated reasonably well

numerical modelling of short and long wave transformation on a barred beach abstract this work aims to demonstrate an advancement towards the integrated modelling of surf zone hydrodynamics by means of a vof type numerical model cobras uc based on the reynolds averaged navier stokes equations in this paper the numerical model is adapted and validated for the study of nearshore processes on a mildly sloping beach the model prediction of wave energy transformation and higher order statistics skewness and asymmetry are in good agreement with detailed laboratory observations from a barred beach boers m 1996 simulation of a surf zone with a barred beach report 1 wave heights and wave breaking tech rep 96 5 comm on hydrol and geol eng dept of civil engineering delft university of technology moreover the numerical model allows us to study the low frequency motions inside the surf zone it is found that in order to achieve a satisfactory simulation of both short and long wave transformation the numerical model must achieve i the simultaneous second order wave generation and absorption ii the energy transfer between triad of components iii the short and long wave energy dissipation inside the surf zone and iv the wave reflection at the shoreline comparisons between numerical and experimental results demonstrate the model capability to satisfactorily simulate all the aforementioned processes

rb sr dating of the bokan mountain granite complex and its country rocks seven out of 11 whole rock samples of the bokan granitic complex give a rb sr isochron date of 151 5 ma late jurassic as a minimum age for the complex this result is discordant with published early to middle jurassic k ar and u pb dates for the same unique peralkaline rock suite a late jurassic age is tenable if excess radiogenic ar and a trace of xenocrystic zircon are postulated to explain the previously reported results and the u pb data are reinterpreted to give an age between 156 6 and granitic country rock for the complex is dated by rb sr at 432 19 ma early silurian in agreement with published k ar dates

numerical analysis of wave overtopping of rubble mound breakwaters abstract the paper describes the results of a two dimensional 2 d numerical modelling investigation of the functionality of rubble mound breakwaters with special attention focused on wave overtopping processes the model cobras uc is a new version of the cobras cornell breaking waves and structures based on the volume averaged reynolds average navier stokes varans equations and uses a volume of fluid technique vof method to capture the free surface the nature of the model equations and solving technique provides a means to simulate wave reflection run up wave breaking on the slope transmission through rubble mounds overtopping and agitation at the protected side due to the combined effect of wave transmission and overtopping also two dimensional experimental studies are carried out to investigate the performance of the model the computations of the free surface and pressure time series and spectra under regular and irregular waves are compared with the experimental data reaching a very good agreement the model is also used to reproduce instantaneous and average wave overtopping discharge comparisons with existing semi empirical formulae and experimental data show a very good performance the present model is expected to become in the near future an excellent tool for practical applications

a partial cell technique for modeling the morphological change and scour abstract a novel partial cell technique applied on structured grids is developed to track the deformation of water soil interface associated with beach morphological change and toe scour in front of coastal structures it allows the use of the same orthogonal structured grids for morphological sediment transport and hydrodynamic models therefore has the advantage of consuming less cpu and without the need to adapt grids to the evolving beach morphology an improved sand slide model with better mass conservation is introduced to resolve the avalanche behaviour of the sediment motion the rans vof hydrodynamic model has been extended to cope with complex bathymetry the newly developed numerical model suite coupling the rans vof model a bedload sediment transport model and a morphological model using the partial cell technique are validated against the analytical solutions and laboratory measurements for different incoming wave conditions local water depths and bottom slopes this study reveals the key processes that govern the behaviour of beach morphology change in front of a vertical coastal structure during storms the model data comparisons demonstrate the robustness of partial cell technique to capture the movement of the water soil interface

the geology of kimberlite pipes of the ekati property northwest territories canada abstract this paper reviews key characteristics of kimberlites on the ekati property nwt canada to date 150 kimberlites have been discovered on the property five of which are mined for diamonds the kimberlites intrude archean basement of the central slave craton numerous proterozoic diabase dykes intrude the area the precambrian rocks are overlain by quaternary glacial sediments no phanerozoic rocks are present however mudstone xenoliths and disaggregated sediment within the kimberlites indicate that late cretaceous and tertiary cover likely

wave overtopping and piling up at permeable low crested structures the paper aims at providing a simple model for evaluating piling up overtopping filtration and rip currents for low crested structures the model is essentially based on mass and momentum balance and on resistance laws that relate piling up and mass fluxes a procedure is suggested and validated against 2d and 3d experimental data this procedure is innovative with respect to existing formulations since it applies both to emerged and submerged structures and it simultaneously accounts for structure permeability return flow through gaps and dissipative effects

tsunami like solitary waves impinging and overtopping an impermeable seawall experiment and rans modeling abstract this study investigates tsunami like solitary waves impinging and overtopping an impermeable trapezoidal seawall on a 1 20 sloping beach new laboratory experiments are performed for describing three typical cases a turbulent bore rushes inland and subsequently impacts and overtops the seawall type 1 a wave directly collapses on the seawall and then generates overtopping flow type 2 and a wave straightforwardly overtops the seawall crown and collapses behind the seawall type 3 a two dimensional volume of fluid vof type model called the cobras cornell breaking and structure model which is based on the reynolds averaged navier stokes rans equations and the k e turbulence closure solver is validated by experimental data and then applied to investigate wave dynamics for which laboratory data are unavailable additionally a set of numerical experiments is conducted to examine the dynamic wave acting force due to waves impacting the seawall effects of wave nonlinearity and freeboard are elucidated special attention is given to a distinct vortex evolutionary behavior behind the seawall in which the dynamic properties of entrapped air bubbles are briefly addressed experimentally and numerically

interaction of non breaking directional random waves with submerged breakwaters the effect of wave irregularity on submerged permeable structures is analyzed existing literature is summarized the relevant theory is presented and theoretical results are compared with existing laboratory data the influence of structure geometry porous material properties and wave characteristics including oblique incidence on the kinematics and dynamics over and inside the breakwater is considered results for unidirectional and multidirectional wave spectra are compared to those obtained for regular waves the model presented reproduces the experimental results fairly well and provides a tool for analyzing several engineering problems such as breakwater stability and breakwater performance

wave induced pressures in porous bonded revetments part i pressures on the revetment abstract revetments made of polyurethane bonded aggregates pba are a recent alternative to mitigate coastal erosion their advantages over conventional impermeable revetments are shown in previous studies based on large scale laboratory tests oumeraci et al 2010 and cfd modelling foyer and oumeraci 2013 the latter were conducted to describe the hydrodynamic and hydro geotechnical processes involved in the wave structure interaction with pba revetments however the data generated did not allow a full description of the wave induced loading of the revetment and the response of the underlying soil therefore a comprehensive parameter study with a computational fluids dynamics computational solid dynamics cfd csd model system was performed this paper part i focuses on the wave induced pressures on the revetment while a companion paper part ii describes the pore pressure development just beneath the revetment and in the embankment subsoil in this first part the following issues are addressed i introduction to the numerical parameter study and the cfd csd model used for the modelling of the wave induced pressures ii brief review of the wave load classification and parameterization to define the elements and notations for the wave induced pressure analysis iii analysis of the peak pressure magnitude its location on the revetment and the spatial pressure distribution and iv the development of prediction formulae based on the results of the analysis in issue iii finally a summary of the key results and concluding remarks are provided including the implications and recommendations for engineering applications as well as for further research

hybrid modeling of pore pressure damping in rubble mound breakwaters abstract rubble mound breakwaters dissipate the incident energy of waves using friction through different layers of porous media the porosity of these layers decreases from the external slope to the core the flow through the breakwater induces high internal pore pressures which might cause breakwater failures indeed high pressure in the core can provoke failure of the armor layer and geotechnical instability the experimental study of the pressure evolution inside a breakwater is tough and the existing semi empirical approximations diverge consequently the analysis of pore pressure damping through a porous media is still an open task however nowadays there are powerful numerical models that can be used with that aim therefore pressure evolution inside the breakwaters is analyzed in this work by means of a combination of experimental numerical and previously existing semi empirical formulations hence a hybrid modeling of pore pressure damping in rubble mound breakwaters is presented here taking advantage of the strengths of each approach after a validation of the numerical modeling using the experimental data the numerical model is used to analyze the pressure field inside the breakwater numerical and physical model results are also compared with existing semi empirical formulae

coastal flooding from wave overtopping and sea level rise adaptation in the northeastern usa abstract in the northeastern united states flooding arising from wave overtopping poses a constant threat to coastal communities during storm events the purpose of this study is to construct a novel integrated atmosphere ocean coast and overtopping drainage modeling framework based on the coupled tide surge and wave model swan adcirc to assess risk and facilitate coastal adaptation and resilience to flooding in a changing climate in this region the integrated modeling system was validated against the field observations of water level wave height and period during the january 2015 north american blizzard the water level collected by a sensor in the avenues basin behind the seawall in scituate massachusetts were combined with the basin relationship between basin area and water level given by the usgs lidar data to obtain the field measurements of wave overtopping water volume in order to verify the model predictions at the storm peak the significant wave height was increased by 0 7 m at the coast by tide and surge the wave setup along the coast varied from 0 1 m to 0 25 m depending on the coastline geometry the interaction between tide surge and waves increased the wave overtopping rate by five folds mainly due to the increased wave height at the toe of the seawall the wave overtopping discharge would approximately double in an intermediate sea level rise scenario of 0 36 m by 2050 for a storm like the january 2015 north american blizzard the wave overtopping discharge would increase by 1 5 times if the seawall crest elevation was raised by the same amount as sea level rise as an adaptation strategy an increase of 0 9 m in the seawall crest elevation instead of 0 6 m currently planned by the town is required to bring the wave overtopping discharge to the current level under a 0 36 m sea level rise scenario this result is primarily due to larger waves arriving at the seawall without breaking in the presence of larger water depth

evolution of the late paleozoic accretionary complex and overlying forearc magmatic arc south central chile 38 41 s constraints for the tectonic setting along the southwestern margin of gondwana stratigraphic structural metamorphic and geochronologic studies of basement rocks in the andean foothills and coast ranges of south central chile 39 41 s suggest a protracted late paleozoic to middle mesozoic deformational and metamorphic history that imposes important constraints on the tectonic development of the southwestern gondwana margin in the study area the late paleozoic paired metamorphic belt coeval magmatic arc and overlying triassic sedimentary units preserve a record of late carboniferous to early permian subduction and arc magmatism subsequent deep exhumation of the western series subduction complex and diminished uplift and erosion of the eastern series arc forearc region by the late triassic late paleozoic structural elements and metamorphic assemblages formed during early subduction and arc magmatism collectively referred to as dl are largely erased in the western series by the dominant d2 schistosity and lower greenschist grade metamorphism d1 structural features as well as original sedimentary textures are relatively well preserved in the less penetratively deformed eastern series the regional distribution of late paleozoic arc magmatism suggests that the late paleozoic convergent margin deviated from a n s trend north of this area to a nw se trend near this latitude and faced an open marine environment to the southwest a transition from f2 isoclinal folding to more open larger scale f3 folds interpreted as change in ductility during differential uplift of the western series is not apparent in the eastern series despite a lesser degree of uplift during the main exhumational d2 event delineation of unconformities and u pb dating of detrital zircons and intrusions into the eastern series allow tighter constraints to be placed on timing of uplift and denudation of the eastern series than on that in the western series a regional unconformity exposed in the lake district that separates more highly deformed eastern series lithologies from late triassic shallow marine to continental deposits suggests that substantial uplift also affected the inner forearc and magmatic arc region during the d2 event we propose that dextral oblique convergence initiated during the middle permian along this segment of the gondwana margin resulted in the transpressional uplift and juxtaposition of high pressure temperature p t western series against low p t eastern series lithologies and culminated with deposition of late triassic continental to shallow marine coarse clastic sedimentary rocks in fault bounded strike slip basins adjacent to the exhumed western series large scale dextral transpression and northward displacement of the accretionary complex during late permian to late triassic time along the chilean margin of gondwana are synchronous and kinematically compatible with widespread regional transpression extension and silicic magmatism inboard of the southern gondwana margin at this time we thank c mpodozis m gardeweg and j munoz of the servicio de geologia y mineria de chile sernageomin for their support of this work fruitful discussions with n blanco f herve h moreno c mpodozis and f munizaga have aided in our understanding of the geology of the region the hard work by the staff of sernageomin s puerto varas office is graciously appreciated we thank j d walker and w r van schmus at the university of kansas for allowing mwm use of their u pb and mass spectrometer facilities and j vargas and the staff of sernageomin s geochemistry laboratory for their assistance in this project f munizaga allowed us to cite an unpublished 40ar 39ar date we thank g ya nez for access to aeromagnetic data t kato wishes to thank w g ernst comments by i dalziel s kay and v ramos helped clarify ideas presented in this paper and are greatly appreciated this work is dedicated to our friend and colleague alberto campos c who died in a climbing accident on calbuco volcano 1996

numerical model of swash motion and air entrapment within coarse grained beaches abstract the paper presents a numerical model for bore driven swash on permeable coarse grained beaches the surface flow module is modelled using the non linear shallow water equations nlswes solved using the godunov based finite volume ader scheme which is suitable for handling steep bores as well as large source terms in the nlswes the subsurface flow comprises i infiltration and exfiltration modelled as vertical piston like flow ii horizontal pore air movement within the unsaturated region of the beach iii the horizontal groundwater flow model predictions of the surface and subsurface flow are in good agreement with measurements from large scale laboratory experiments for swash on permeable immobile beaches in these simulations air velocity was sufficiently small to justify using darcy s resistance law for the air flow whereas the quadratic forchheimer law had to be used for the infiltration and groundwater flow the validated numerical model provides insight into the surface subsurface water exchange for bore driven swash on coarse grained beaches the impact of air entrapped between the wetting front and the groundwater level on the water exchange is examined in particular

the triassic cobquecura pluton central chile an example of a fayalite bearing a type intrusive massif at a continental margin abstract the late triassic cobquecura pluton is a small epizonal intrusive body that was emplaced into the paleozoic basement at the western side of the cordillera de la costa near to the town of cobquecura 35 57 36 12 s central chile the pluton displays a wide spectrum of compositions that include gabbro and fayalite granite and less abundant hybrid rocks sio2 content ranges from 48 to 76 wt with a compositional gap between 57 and 63 wt sio2 sio2 poor rocks have mg fe minerals olivine fa33 34 diopside augite mg 56 91 mg mg mg fe2 100 and pargasite mg 4 8 which with progressive differentiation become fe rich olivine fa89 98 hedenbergite ferroaugite mg 10 43 and ferroedenite mg 8 29 similar k ar isotopic ages mingling structures and coherent arrays in harker diagrams as well as mineral compositions show that the sio2 poor and sio2 rich rocks are comagmatic the fe rich mineralogy and ga content of the cobquecura pluton point to an anorogenic a type magmatism the compositional similarities as well as the bimodal character of the magmatism of cobquecura and other upper triassic granitoids and lavas north of 30 s at the chilean continental margin indicate a common origin of the magmatism with anorogenic signature and coeval processes along the southwestern margin of gondwana in the triassic

breaking wave induced response of composite breakwater and liquefaction in seabed foundation abstract in the practice of engineering breaking wave is much more dangerous for the stability of composite breakwater built on porous seabed than non breaking wave in offshore area in previous investigations or design codes the empirical formulations generally were adopted to estimate the wave impact acting on the lateral side of caisson the interaction between breaking wave seabed foundation and composite breakwater is not taken into consideration in this study adopting the integrated numerical model poro wssi 2d developed by ye 2012a and jeng et al 2013 the interaction mechanism between breaking wave seabed foundation and composite breakwater is investigated numerically in poro wssi 2d the volume averaged reynolds averaged navier stokes varans equations govern the wave motion and the porous flow in seabed foundation and in rubble mound and the dynamic biot s equations known as u p approximation govern the dynamic behaviors of seabed foundation and composite breakwater under breaking wave loading numerical analysis indicates that the turbulent energy of breaking wave is significant and the wave impact on caisson applied by breaking wave is much greater than non breaking wave the composite breakwater and its seabed foundation respond to the breaking wave loading intensively the maximum horizontal vibration magnitude of the composite breakwater is up to 5 mm the maximum liquefaction depth in the seabed in front of the composite breakwater reaches up to 1 2 to 1 6 m the parametric study shows that the permeability and saturation of seabed wave height are three dominant factors for the wave induced liquefaction in seabed foundation

experimental and numerical investigation of bed morphology in the lee of porous submerged breakwaters abstract in the present work the evolution of a sandy beach in the lee of a permeable submerged breakwater was studied both experimentally and numerically three dimensional laboratory experiments were performed to investigate regular and irregular wave propagation over a porous submerged structure and the resulting bed morphology evolution down wave of it the tests included normal wave incidence of breaking and non breaking long and shorter waves the measurements were also used to validate a compound numerical model the basic solver relies on enhanced boussinesq type equations extended to simulate wave propagation over porous beds the wave module accounts for the entire nearshore zone from deep water to the swash zone and it is coupled with a sediment transport module including both bed and suspended loads adequate agreement between measurements and model results was achieved in most cases

a type granites in northeastern china age and geochemical constraints on their petrogenesis abstract a type granites are widely distributed in northeastern china ne china they were emplaced during three major episodes the permian late triassic to early jurassic and early cretaceous and evolved in different tectonic regimes according to their mineralogical and geochemical characteristics two subgroups of a type granites aluminous and peralkaline can be recognized the peralkaline subgroup contains alkali mafic minerals such as riebeckite arfvedsonite and sodic pyroxene while the aluminous subgroup contains annite and fe rich calcic or sodic calcic amphibole with respect to the aluminous subgroup the peralkaline granites contain higher rb ga and total rare earth elements ree but lower mgo cao al 2 o 3 ba and sr based on the discrimination criteria of eby geology 20 1992 641 the permian and late triassic to early jurassic a type granites belong to the a 2 post orogenic type whereas the early cretaceous granites are of the a 1 anorogenic type nd isotopic compositions of these a type granites indicate their derivation from a dominantly juvenile crustal source their origin is thought to have involved partial melting of an underplated lower crustal source because the generation of a type granites requires high melting temperature we propose models involving slab break off lithospheric delamination and extension the permian a type granites have the same age range as those in eastern junggar southern mongolia and central inner mongolia they occur along a major suture and form a narrow belt between the north china and siberian cratons we suggest that their formation was associated with post collisional slab break off the late triassic to early jurassic a type granites are likely to be the product of lithospheric delamination after the final collision of the major crustal blocks in the late paleozoic to early triassic the early cretaceous a type granites have an anorogenic affinity and were possibly associated with rifting in eastern china at this time associated with the onset of paleo pacific subduction consequently we conclude that the a type granites in ne china were generated at three different times involving multiple processes operative in different tectonic environments

composition gaps critical crystallinity and fractional crystallization in orogenic calc alkaline magmatic systems the recognition of a three way correlation between magmatic sio2 content critical crystallinity and the size magnitude of crystal fractionation generated composition gaps in calc alkaline magmatic systems suggests an important control of magmatic critical crystallinity on the formation of such composition gaps to explain this correlation it is proposed that fractionation generated composition gaps are caused by 1 simultaneous interior i e non substrate crystallization and vigorous chamberwide convection which leads to progessive crystal suspension 2 cessation of convection when the percentage of suspended crystals reaches the critical crystallinity of the magma and 3 eventual buoyancy driven crystal liquid segregation producing a discrete body of fractionated magma which is separated from the initial magma by a composition gap this mechanism implies that many if not most magma bodies are characterized by interior crystallization and vigorous convection conditions which are not universally agreed upon at present given that such conditions characterize natural magma bodies fractional crystallization through crystal settling in low velocity boundary layers should be an important mechanism of fractional crystallization in a crystallizing and convecting body of magma composition gap formation should represent one endmember of a complete spectrum of possible evolutionary paths governed by the relative rates of crystal settling and crystal retention as a given volcanic plumbing system matures with time average settling retention ratios within individual magma bodies should increase due to higher average wall rock temperatures it follows that within a given volcanic center early stage volcanism should be more likely to display fractionation generated composition gaps than later stage volcanism such a temporal evolution has been documented at at least two aleutian calc alkaline volcanic centers

a numerical study of swash flows generated by bores abstract article history received 10 october 2007received in revised form 15 march 2008accepted 4 april 2008available online 4 june 2008keywords swash zonetsunami runupdam breakborenon linear shallow water equationsreynolds averaged navier stokes equationnon linear k model the dynamic processes of bore propagation over a uniform slope are studied numerically using a 2 dreynolds averaged navier stokes rans solver coupled to a non linear k turbulence closure and avolume of uid vof method the dam break mechanism is used to generate bores in a constant depthregion present numerical results for the ensemble averaged ow eld are compared with existingexperimental data as well as theoretical and numerical results based on non linear shallow water nsw equations reasonable agreement between the present numerical solutions and experimental data isobserved using the numerical results small scale bore behaviors and ow features such as the bore collapseprocess near the still water shoreline the mini collapse during the runup phase and the back wash bore inthe down rush phase are described in the case of a strong bore the evolution of the averaged turbulencekinetic energy tke over the swash zone consists of two phases in the region near the still water shoreline the production and the dissipation of tke are roughly in balance in the region farther landwards of the still water shoreline the tke decay rate is very close to that of homogeneous grid turbulence on the other hand in the case of a weak bore the bore collapse generated turbulence is con ned near the bottom boundarylayer and the tke decays at a much slower rate 2008 elsevier b v all rights reserved

2 d numerical analysis of near field flow at low crested permeable breakwaters abstract this paper describes the capability of a numerical model named cornell breaking waves and structures cobras lin p liu p l f 1998 a numerical study of breaking waves in the surf zone journal of fluid mechanics 359 239 264 liu p l f lin p chang k a sakakiyama t 1999 numerical modeling of wave interaction with porous structures journal of waterway port coastal and ocean engineering 125 322 330 liu p l f lin p hsu t chang k losada i j vidal c sakakiyama t 2000 a reynolds averaged navier stokes equation model for nonlinear water wave and structure interactions proc coastal structures 99 169 174 based on the reynolds averaged navier stokes rans equations to simulate the most relevant hydrodynamic near field processes that take place in the interaction between waves and low crested breakwaters the model considers wave reflection transmission overtopping and breaking due to transient nonlinear waves including turbulence in the fluid domain and in the permeable regions for any kind of geometry and number of layers small scale laboratory tests were conducted in order to validate the model with different wave conditions and breakwater configurations in the present study regular waves of different heights and periods impinging on a wide crested structure are considered three different water depths were tested in order to examine the influence of the structure freeboard the experimental set up includes a flow recirculation system aimed at preventing water piling up at the lee of the breakwater due to overtopping the applicability and validity of the model are examined by comparing the results of the numerical computations with experimental data the model is proved to simulate with a high degree of agreement all the studied magnitudes free surface displacement pressure inside the porous structure and velocity field the results obtained show that this model represents a substantial improvement in the numerical modelling of low crested structures lcs since it includes many processes neglected previously by existing models the information provided by the model can be useful to analyse structure functionality structure stability scour and many other hydrodynamic processes of interest

investigations on the porous media equations and resistance coefficients for coastal structures abstract this paper considers the flow in porous media that occurs in coastal and offshore engineering problems over the past decades numerous formulations of flow equations for porous media have been presented the present work re examines the porous media equations of the most recent form and corrects some shortcomings which were identified the applied type of porosity models relies on empirical resistance coefficients which often need to be measured or calibrated only few examples of calibration for numerical models which are present in the literature often applied the same experimental results in this study new calibration cases were introduced to the calibration procedure in order to achieve a better understanding of the variation of the resistance coefficients hereby the coefficients were determined with a better description over the entire parameter space for the resistance coefficients than previously found in the literature constant values for the resistance coefficients for a broad range of flow conditions were recommended based on the new calibrations the model was validated for the main physical processes that occur in wave structure interaction in coastal structures including three dimensional wave structure interaction run up run down and pressure damping regular and irregular wave conditions and evaluation of overtopping simple two and three dimensional uniform caisson structures and breakwater layouts were investigated the model was implemented in the open source cfd library openfoam and has been made publicly available to the engineering community as part of the wave generation framework waves2foam