large scale sediment transport patterns on the continental shelf and influence on shoreline response st andrew sound georgia to nassau sound florida usa abstract regional sediment transport patterns on the continental shelf seaward of cumberland island georgia and amelia island florida are documented using historical shoreline position and bathymetry data spatial variability in the net rate of shoreline change is considerable due to jetty construction at st marys entrance in the early 1900s net average shoreline progradation is documented for both islands 1 5 m yr for cumberland and 0 4 m yr for amelia however localized areas of shoreline retreat are recorded along amelia island especially for the southernmost 5 km of beach where erosion has been chronic since 1871 rapid shoreline progradation adjacent to the jetties accompanied sediment deposition by longshore sediment transport simultaneously a large quantity of sediment from the natural ebb tidal delta was reworked and transported offshore in response to jetty construction and channel dredging creating the modern ebb tidal delta patterns of sediment movement at this inlet and throughout the study area indicate a dominant direction of drift to the south southeast sediment losses and gains were quantified to evaluate long term coastal change within the framework of a sediment budget qualitative descriptions of net sediment transport were integrated with quantitative results to produce a model of large scale coastal evolution for the study area from this analysis net sediment transport in this coastal compartment is controlled by inlet and shelf hydraulics and littoral zone processes have minimal impact on net long term coastal change

late palaeozoic to neogene geodynamic evolution of the northeastern oman margin when the highlands of arabia were still covered with an ice shield in the latest carboniferous early permian period separation of gondwana started this led to the creation of the batain basin part of the early indian ocean off the northeastern margin of oman the rifting reactivated an infra cambrian rift shoulder along the northeastern oman margin and detritus from this high was shed into the interior oman basin whereas carbonate platform deposits became widespread along the margin of the neo tethys northern rim of oman drifting and oceanization of the batain basin started only in late jurassic early cretaceous time extensional tectonics was followed in the late cretaceous by contraction caused by the northward drift of greater india and afro arabia this resulted in the collision of afro arabia with an intra oceanic trench and obduction of the semail ophiolite and the hawasina nappes south to southwestward onto the northern oman margin 80 m y ago during the middle cretaceous the oceanic lithosphere including the future eastern ophiolites of oman drifted northwards as part of the indian plate at the cretaceous palaeogene transition 65 ma oblique convergence between greater india and afro arabia caused fragments of the early indian ocean to be thrust onto the batain basin subsequently the lower permian to uppermost maastrichtian sediments and volcanic rocks of the batain basin along with fragments of indian ocean floor eastern ophiolites were obducted northwestward onto the northeastern margin of oman palaeogene neo autochtonous sedimentary rocks subsequently covered the nappe pile tertiary extensional tectonics related to red sea rifting in the late eocene was followed by miocene shortening associated with the collision of arabia and eurasia and the formation of the oman mountains

late cretaceous to late eocene hekimhan basin central eastern turkey as a supra ophiolite sedimentary magmatic basin related to the later stages of closure of neotethys abstract the hekimhan basin is here put forward as a type example of a globally important class of basin known as a supra ophiolite basin such basins form after the emplacement of ophiolitic i e oceanic rocks onto a passive continental margin but long prior to continental collision the hekimhan basin developed as part of the northern margin of the tauride microcontinent during the collision and suturing of two neotethyan oceans to the north namely the inner tauride ocean and the izmir ankara erzincan ocean the basin records two main stages of tectonic development during latest cretaceous to late eocene time the first phase of basin development during the late cretaceous maastrichtian began with the erosion of emplaced ophiolitic rocks resulting in non marine clastic sedimentation subsequently the basin rapidly subsided in response to inferred regional crustal extension resulting in the deposition of hemipelagic marls and local sapropelic mudstones the axial parts of the basin experienced alkaline within plate type basaltic volcanism the late maastrichtian culminated in deposition of shallow marine carbonates overlying paleocene sediments are restricted to thin localised marine evaporates associated with a low angle unconformity the second stage of basin development began during the early eocene with deposition of shallow marine carbonates coupled with localised basaltic volcanism again of extensional type the basin emerged during the mid late eocene in a late stage collisional to post collisional setting compressional deformation largely reflects post suture tightening a short lived marine transgression occurred during the mid miocene the basin was later deformed by both left lateral and right lateral strike slip several different tectonic models are considered notably extension related to the northward pull of a still subducting oceanic slab and back arc extension related to northward subduction of neotethys to the south the first alternative is consistent with the development of adjacent supra ophiolite basins e g ulukisla and darende basins and also with supra ophiolite basins elsewhere e g se turkey balkans oman

aster mapping of limestone formations and study of caves springs and depressions in parts of sultanate of oman caves springs and large depressions of limestone karst formations are becoming more attractive tourist places and have potential importance on socio economic development the present study is a multi scale point of view on limestone karst from the space images to microscopic fabric here the karst features consist of limestone formations of cretaceous albian cenomanian age of tanuf valley and tertiary late paleocene middle eocene age of sur region of parts of sultanate of oman which are mapped in the visible near infrared and shortwave infrared spectral bands of advanced spaceborne thermal emission and reflection radiometer aster using decorrelated stretch image processing technique and the occurrences of caves springs and depressions of the formations in the field were studied the decorrelated rgb images of aster spectral bands 8 3 and 1 discriminated well the limestone formations and associated lithology the limestone formations of tanuf valley natih formations of hajar unit are thick bedded massive shallow marine limestone and clayey limestone which have caves and springs large depressions are studied as collapsed structures at the boundary between abat formations they consist of gray to white marly or micritic limestone with chert nodules and seeb formation of bioclastic limestone calcarenite marl and sandstone of sur region interpretations of limestone formations their occurrences and distributions of caves springs and depressions of these regions are verified and confirmed in the field and studied in the laboratory occurrences of more springs and depressions in the limestone formations of the study sites are interpreted and located on the google earth image the study proved the capability of aster sensor in mapping of limestone formations and recommends the technique to other geographical regions where similar geological questions need to be resolved

hydrodynamics and equilibrium of a multiple inlet system although it is generally acknowledged that most multiple inlets are unstable and cannot coexist there is evidence to suggest that such inlets can indeed be stable over decadal time scales multiple inlet systems servicing a single embayment in contrast to single inlet systems confer particular hydrodynamic characteristics such as the potential existence of residual discharges and currents between the inlets this paper presents detailed measurements of hydrodynamic variables obtained over complete spring and neap tidal cycles in a multiple inlet system in southern portugal ria formosa the results indicate that the two main interconnected inlets servicing an embayment can coexist at least over a time scale of several decades however their coexistence cannot be explained simply using empirical equilibrium relations or inlet hydraulics although residual flow between the inlets appears to play an important role enhancing their stability it is the availability of sediment stored in the ebb tidal deltas and its capacity to be carried into the inlets during storm events that ultimately dictates the overall equilibrium independently of the flushing capability provided by the hydraulics such movement of sediment leads to the obstruction of the inlet channels thereby affecting the hydraulic efficiency and eventually leading to inlet closure in the long term the results augment existing knowledge concerning multiple inlet systems and improve understanding of their short to medium term stability

evolution and facies architecture of the mesotidal guadiana river delta s w spain portugal abstract the guadiana river estuary and delta is one of the most important mesotidal fluvio marine systems of the southwestern iberian peninsula the river mouth was formed as a narrow channel excavated by fluvial incision during the pleistocene lowstand and then flooded 6500 yr ago during the flandrian transgression holocene the estuary is in an advanced state of sediment infilling in its proximal part due to its narrow morphology which prevents passage of sediment through to the open coast consequently sediment is accumulating in the river mouth causing progradation as response of the interaction between coastal and fluvial processes sedimentation is controlled by the interaction of sediment load delivered by the guadiana river and the active longshore current which also supplies sand eroded from barrier islands and friable cliffs in the portuguese algarve to the west tidal range is mesotidal 2 0 m and mean significant wave height is 0 6 m with an average period of 3 6 s morphological differences exist between the two sides of the river mouth the western side has a large spit separated from the mainland by a marsh and the eastern side shows an array of old barrier islands separated by salt marsh areas a vibracore study allows us to distinguish 12 different depositional facies in the system fluvial delta tidal inlet flood tidal delta washover beach dune estuarine channel lagoon tidal creek channel margin tidal flat and salt marsh furthermore a different architectural scheme of these facies is present on each side to the east there is a longitudinal repetition of the sandy facies corresponding to the barrier islands on the west side there is a transverse growth of a single spit containing eolian dunes these differences result from asymmetric interaction between the tidal and fluvial currents at the river s mouth and the waves and tidal currents of the open coastal zone

beach response to a fixed sand bypassing system abstract indian river inlet is located at roughly the mid point of the atlantic coast of delaware and connects the ocean to two delaware inland bays jetties constructed in 1940 have maintained the inlet for navigation purposes but have also acted as a barrier to net northerly alongshore sediment transport causing downdrift erosion a mobile land based bypassing system was initiated in 1990 in an effort to counteract this erosion beach profile data from 1985 pre bypassing until 2008 are used to investigate the effect of the sand bypassing system on beaches adjacent to the inlet the downdrift beach experienced horizontal shoreline erosion between 10 and 60 m during the pre bypassing period but accreted 10 20 m during the bypassing period the mean shoreline location on the updrift beach during bypassing is 10 20 m landward erosion of its position during the pre bypassing period empirical orthogonal function eof amplitudes from analyses performed on mean removed elevation surfaces during the periods of highest bypassed volume average of 83 of design rate showed that the influence of the bypassing system on the downdrift beach extends to about 1500 m of the inlet an eof analysis showed that different morphologic responses were evident following the initiation of bypass operations temporal variations of shoreline and beach morphology were correlated to the temporal variations in bypassing rates on the downdrift beach only the downdrift beach response was greatest near the inlet for larger bypassing volumes correlation in these instances occurred with a roughly 1 year time lag suggesting that the beach quickly redistributes the bypassed sand eof amplitude and shoreline response are weakly correlated to bypassed volumes when the system bypassed smaller volumes average of 56 of design rate of sand suggesting that there is a minimum bypassing rate regardless of yearly variability below which the effect on the downdrift beach is obscured

basanites related to late eocene extension from ne oman six small basanite intrusions were emplaced into the allochthonous batain nappes of ne oman along approximately north south to nnw sse lineaments they contain olivine clinopyroxene plagioclase analcite ulvospinel and apatite biotite calcite the basanites are primitive with mg numbers 100mg mg fe 2 from 63 18 to 69 37 and are nepheline normative compositional variation suggests fractionation of olivine and clinopyroxene thermobarometric studies on rare spinel lherzolite xenoliths suggests re equilibration at shallow depth 143 nd 144 nd and 87 sr 86 sr isotopic data and ree modelling indicate that the magmas were formed by 1 2 melting of an ocean island basalt oib like source containing about 3 4 garnet deviations from oib are explained by mobilization of incompatible elements from potassic layers in the lithosphere during ascent sedimentological studies and three new whole rock ar ar ages 39 77 0 26 37 63 0 46 and 36 51 0 21 ma lutetian to priabonian time suggest intrusion during maximum deepening of the abat trough movements were related to dextral strike slip movement along major tectonic structures during the initial stages of the opening of the gulf of aden the basanites were formed by decompressional melting of an asthenospheric mantle source facilitated by thinned lithosphere and depression of the solidus by h 2 o and co 2 rich fluids

two stage development of the late cretaceous to late eocene darende basin implications for closure of neotethys in central eastern anatolia turkey

tidal and river discharge forcing upon water and sediment circulation at a rock bound estuary guadiana estuary portugal the relative impacts of tidal neap spring and river discharge including a flood event forcing upon water and sediment circulation have been examined at the rock bound guadiana estuary near bed and vertical profiles of current salinity turbidity plus surface suspended sediment concentrations ssc at some stations only were collected at the lower and central upper estuary during tidal and fortnightly cycles in addition vertical salinity and turbidity profiles were collected around high and low water along the estuary tidal asymmetry produced faster currents on the ebb than on the flood especially at the mouth this pattern of seaward current dominance was enhanced with increasing river flow due to horizontal advection that was confined within the narrow estuarine channel the freshwater inputs and at a degree less the tidal range controlled the vertical mixing and stratification importance well mixed spring and partially stratified neap conditions alternated during periods of low river flows with significant intratidal variations induced by tidal straining especially at the partially stratified estuary highly stratified conditions developed with increasing river discharge intratidal variability in the pycnocline depth and thickness resulted from current shear during the ebb a salt wedge with tidal motion was observed at the lower estuary during the flood event depending on the intensity of turbulent mixing the residual water circulation was dominantly controlled either by tidal asymmetry or gravitational circulation the ssc was governed by cyclical local processes resuspension deposition mixing advection driven by the neap spring fluctuations in tidal current velocities more intratidal variability in stratification indicated the significance of tidal pumping at the partially and highly stratified estuary the estuary turbidity maximum etm was enhanced with increasing current velocities and displaced downstream during periods of high river discharge during the flood event the etm was expelled out of the estuary and the ssc along the estuary was controlled by the sediment load from the drainage basin under these highly variable river flow conditions our observations suggest that sand is exported to the nearshore over the long term years

mantle xenolith bearing maastrichtian to tertiary alkaline magmatism in oman 1 mantle xenolith bearing alkali basalts basanites and tephrites with 1 5 2 k2o and 4 5 wt na2o occur as small 100 m plugs and dikes in the batain and haushi huqf areas and wnw of muscat their black color and the common presence of peridotite xenoliths allow a separation from older alkaline rocks and from the ophiolitic extrusive rocks two main dike directions approximately e w and n s oriented are observed intrusions seem to occur where these two fault systems intersect the basalts crosscut the upper maastrichtian siliciclastic rocks of the fayah formation and the nappe stack of the eastern ophiolite belt of the batain area they have not been observed intruding the tertiary shallow marine carbonates although k ar whole rock dating on these lavas yielded late eocene 37 1 to 44 1 ma ages the rocks are aphyric and fine grained with microgranular and less common microtrachytic texture they contain magmatic olivine fo80 82 nepheline ne82 86ks14 18 clinopyroxene di46en25wo28 with 2 5 wt al2o3 accessory phlogopite xmg0 6 with 5 5 wt tio2 in a microcrystalline or glassy matrix plagioclase is only observed in few samples locally occurring mm to cm sized immiscible leucocratic melt droplets consist of potassium feldspar an1 4ab37 39or60 70 plagioclase an20 22ab65or13 15 nepheline ne85ks15 phlogopite xmg0 8 with 6 7 wt tio2 and titanomagnetite with 8 wt tio2 more than 95 of the xenoliths are 5cm sized weakly to clearly foliated spinel peridotites of mantle origin sedimentary xenoliths hornfelses are rare and lower crustal xenoliths were not found the peridotite xenoliths consist of olivine fo90 92 enstatite en89fs09wo02 with 3 1 3 3 wt al2o3 diopside di45en26wo29 with 3 6 wt al2o3 and cr spinel with 60 mol spinel 20 hercynite and 15 16 magnesiochromite the age chemical composition and structural position suggest a relation with local tectonic movements associated with plate reorganization in the owens basin region prior to the red sea opening

termination of the arabian shelf sea stacked cyclic sedimentary patterns and timing oligocene miocene oman abstract in the janabah region of southeastern oman oligocene miocene limestones of the shuwayr warak and ghubbarrah formations are widely exposed they were deposited on an extensive shallow carbonate platform that was part of the arabian shelf and located on the gulf of aden s northeastern rift shoulder which emerged during the early miocene the uppermost part of the studied sedimentary succession developed immediately before the permanently subaerial exposure of the carbonate platform cyclic changes of intertidal and subtidal facies document a fluctuating relative sea level at different frequencies and a continuous decline of accommodation single erosive surfaces with palaeokarst cavities and caliche crusts separate larger depositional cycles these disconformities imply relatively long episodes of subaerial exposure and are interpreted to have been formed during lowstands of third order sea level cycles that denuded the platform taxonomic studies of the accompanying mollusc faunas and certain benthic foraminifers allow a correlation of the recognised subaerial disconformities with the ru4 ch1 to ch4 aq1 sequence boundaries of hardenbol et al hardenbol j thierry j farley m b jacquin t graciansky p c vail p r 1998 mesozoic and cenozoic sequence chronostratigraphic framework of european basins in graciansky c p hardenbol j jacquin t vail p r eds mesozoic and cenozoic sequence stratigraphy of european basins society for sedimentary geology special publication 60 13 603 this demonstrates that the termination of the arabian shelf sea must be back dated from the middle burdigalian to the early aquitanian

decadal morphological response of an ebb tidal delta and down drift beach to artificial breaching and inlet stabilisation abstract the morphodynamic response of a mixed energy ebb tidal delta guadiana estuary southern portugal and its down drift barrier island canela island to channel relocation and stabilisation by jetties is examined using a series of sequential bathymetric maps and vertical aerial photographs spanning five decades morphological analysis indicates that the ebb delta is in an immature state characterised by weak sediment bypassing landward migrating shoals on the swash platform have been produced by the jetty induced artificial bank breaching and by the collapse of the eastern portion of the delta the welding of these shoals has largely controlled the evolution of the coast with local accretion and erosion lasting for years and large amounts of regional accretion occurring over decades due to sand accumulation against jetties located further down drift these observations provide insights into the potential response of a coast to very large locally concentrated sand nourishment in the form of shoals the main effects of the jetties on the coast are observed at the centre of canela island with the production of an erosion hot spot associated with a temporally persistent and divergent longshore transport providing sand to the adjacent areas significant accretion is anticipated for the next decade along the entire island due to the ongoing attachment of the presently observed shoals after the depletion of this sediment source and in the context of weak sediment bypassing the most severe down drift erosion induced by the jetties is predicted to occur some decades after their construction this study demonstrates that the geomorphic response of an ebb tidal delta to jetty construction must be considered at multiple temporal and spatial scales when assessing the impacts of jetties on the down drift coast

west northwest directed obduction of the batain group on the eastern oman continental margin at the cretaceous tertiary boundary the batain coast area in eastern oman is dominated by allochthonous permian to late maastrichtian sedimentary and volcanic rocks batain group unconformably overlain by neoautochthonous tertiary sediments the allochthonous rocks of the batain coast were previously attributed to the hawasina complex the permian to coniacian santonian sedimentary infill of the neo tethyan hawasina basin off northern oman previous structural interpretations suggested that the batain group along with the hawasina complex and the semail ophiolite was obducted in the coniacian to campanian from ne to sw onto the northern oman continental margin results of our work in the batain area differ from previous interpretations with most significant differences concerning timing and direction of obduction our results show that wnw directed tectonic movements formed a fold and thrust belt and led to the obduction of allochthonous rocks onto the east oman continental margin during latest maastrichtian earliest paleocene times this is coeval with emplacement of ophiolitic fragments along the eastern coast of oman eastern ophiolite belt but is about 15 20 myr later than emplacement of hawasina complex and semail ophiolite in northern oman postemplacement structural evolution during the tertiary involved intraplate extension possibly reflecting the red sea gulf of aden opening and late tertiary shortening related to convergence between arabia and eurasia late tertiary contractional deformation resulted in refolding of the batain nappes and in folding of the overlying tertiary sediments a palinspastic reconstruction of the batain area indicates that the permian to upper cretaceous sediments were formerly deposited in the batain basin a part of the proto indian ocean along the present day eastern oman margin this leads us to propose that permian breakup of gondwanaland created both continental margins of oman and led to the opening of two major basins the neo tethyan hawasina basin in the north and the proto indian ocean batain basin in the east the latter separating arabia from greater india

spatial structure of rainfall in mid latitude cold front systems abstract experimental evidence and physical interpretation of rainfall spatial distribution associated with cold front systems in an inland region 2282 km 2 of the mediterranean area are provided by using a representation on the meso local scale postfrontal and prefrontal storm ensembles consisting of thirty two and seven components respectively were considered for postfrontal storms the distribution of storm total depth was found to be mainly determined by small mesoscale precipitation areas of random nature with orographic effects that in the average were represented by a ratio of 1 5 between rainfall depth over the hills and in a lowland area just upwind of them however despite the basic role of random effects it was possible to divide the study region into a restricted number of homogenous zones whose structure appears to be linked with orography for prefrontal storms the orographic enhancement was more considerable with the above ratio expressed by a value of 2 5 the enhancement was limited by the absence of contributions to surface rainfall due to a seeder feeder process the occurrence of an effect of inhibition of forced uplift which accompanied both the storm types and was caused by fairly modest orography is also discussed such a mechanism frequently produced a weakening or dissipation of pre existing precipitation and may take on an important role in problems of rainfall analysis over real basins

a continental outbreak of air during the second aerosol characterization experiment ace 2 a lagrangian experiment a mesoscale meteorological model is used to simulate the continental outbreak of air that occured over north atlantic ocean during the second aerosol characterization experiment ace 2 comparison with meteosat 6 visible images shows that the model is able to reproduce most of the observed cloud features in the entire modeling domain including a frontal system orographic clouds over the pyrenees and the iberian peninsula boundary layer clouds in the ace 2 region and cloud free areas in the dry air outflow off the portuguese coast the model reproduces correctly the temperature humidity wind speed and direction cloud water content and light precipitation events observed by the aircraft during the lagrangian experiment while following a tagged boundary layer air parcel over a 28 hour long period a passive tracer introduced in the model at the time corresponding to the balloon launch followed the balloon track with an error in position that is smaller than 1 after 24 hours with about 20 higher speed an estimate of the boundary layer entrainment velocity is obtained based on observed boundary layer growth rates and modeled vertical wind speed the average entrainment velocity of 1 28 cm s for the 28 hour lagrangian period agrees with experimentally derived entrainment velocities

masirah graben oman a hidden cretaceous rift basin reflection seismic data well data geochemical data and surface geology suggest that a cretaceous rift basin exists beneath the thrusted allochthonous sedimentary sequence of the masirah graben oman the masirah graben is located east of the huqf uplift parallel to the southern coast of oman the eastern side of the northeast trending huqf anticlinorium is bounded by an extensional fault system that is downthrown to the southeast forming the western edge of the masirah graben this graben is limited to the east by a large wedge of sea floor sediments and oceanic crust that is stacked as imbricate thrusts these sediments ophiolites were obducted onto the southern margin of the arabian plate during the collision of the indian afghan plates at the end of the cretaceou most of the masirah graben is covered by an allochthonous sedimentary sequence which is complexly folded and deformed above a detachment this complexly deformed sequence contrasts sharply with what is believed to be a rift sequence below the ophiolites the sedimentary sequence in the masirah graben was stable until further rifting of the arabian sea gulf of aden in the late tertiary resulting in reactivation of earlier rift associated faults wells drilled in the masirah graben in the south penetrated reservoir quality rocks in the lower cretaceous natih and shuaiba carbonates analyses of oil extracted from infracambrian sedimentary rocks penetrated by these wells suggest an origin from a mesozoic source rock

tracking the paleogene india arabia plate boundary the location of the india arabia plate boundary prior to the formation of the sheba ridge in the gulf of aden is a matter of debate a seismic dataset crossing the owen fracture zone the owen basin and the oman margin was acquired to track the past locations of the india arabia plate boundary we highlight the composite age of the owen basin basement made of paleocene oceanic crust drilled on its eastern part and composed of pre maastrichtian continental and oceanic crust overlaid by ophiolites emplaced in early paleocene on its western side a major fossil transform fault system crossing the owen basin juxtaposed these two slivers of lithosphere of different ages and controlled the uplift of marginal ridges along the oman margin this transform system deactivated 40 myrs ago coeval with the onset of ultra slow spreading at the carlsberg ridge the transform boundary then jumped to the edge of the present day owen ridge during the late eocene oligocene period before seafloor spreading began at the sheba ridge this migration of the plate boundary involved the transfer of a part of the indian oceanic lithosphere formed at the carlsberg ridge to arabia this late eocene oligocene tectonic episode at the india arabia plate boundary is synchronous with a global plate reorganization event corresponding to geological events at the zagros and himalaya belts the owen ridge uplifted later in late miocene times and is unrelated to any major migration of the india arabia boundary

morphodynamic behaviour of a mixed sand gravel ebb tidal delta deben estuary suffolk uk the morphodynamics of inlets and ebb tidal deltas reflect the interaction between wave and tidal current driven sediment transport and significantly influence the behaviour of adjacent shorelines studies of inlet morphodynamics have tended to focus on sand dominated coastlines and reference to gravel dominated or gravel rich inlets is rare this work characterises and conceptualises the morphodynamics of a meso tidal sand gravel inlet at the month of the deben estuary southeast england behaviour of the inlet and ebb tidal delta over the last 200 yr is analysed with respect to planform configuration and bathymetry the estuary inlet is historically dynamic with ebb tidal shoals exhibiting broadly cyclic behaviour oil a 10 to 30 yr timescale quantification of inlet parameters for the most recent cycle 1981 2003 indicate an average ebb delta volume of 1 x 10 6 m 3 and inlet cross sectional area of 775 m 2 bypassing volumes provide a direct indicator of annual longshore sediment transport rate over this most recent cycle of 30 40 x 10 3 m 3 yr 1 short term increases in total ebb tidal delta volume are linked to annual variability in the north to northeasterly wind climate the sediment bypassing mechanism operating in the deben inlet is comparable to the ebb delta breaching model of fitzgerald fitzgerald d m 1988 shoreline erosional depositional processes associated with tidal inlets in aubrey d g weishar l ed hydrodynamics and sediment dynamics of tidal inlets springer verlag inc new york pp 186 225 although the scales and rates of change exhibited are notably different to sand dominated systems a systematic review of empirical models of sand dominated inlet and ebb tidal delta morphodynamics e g those of o brien m p 1931 estuary tidal prisms related to entrance areas civil engineering 1 738 739 walton t l and adams w d 1976 capacity of inlet outer bars to store sand proceedings of 15th coastal engineering conference 1919 1937 gaudiano d j kana t w 2001 shoal bypassing in mixed energy inlets geomorphic variables and empirical predictions for nine south carolina inlets j coast res 17 2 280 291 shows the deben system to be significantly smaller yet characterised by a longer bypassing cycle than would be expected for its tidal prism this is attributed to its coarse grained sedimentology and the lower efficiency of sediment transporting processes c 2005 elsevier b v all rights reserved

the numerical simulation of clouds rains and airflow over the vosges and black forest mountains a meso β model with parameterized microphysics abstract a three dimensional meso model with parameterized microphysics is presented the model is capable of simulating orographically forced clouds rain and airflow tests using a two dimensional version confirm the ability of the model to replicate the linear and nonlinear mountain wave simulations of previous authors the model is applied to the rhine valley and surrounding mountainous areas the vosges in france and the black forest in germany model predicted rainfall over the mountainous areas is in good agreement with observations in both magnitude and location however an absence of model predicted cloud cover over the rhine valley suggests the need for an improved mesoscale initialization procedure

review mesoscale modelling in complex terrain abstract this review focuses on those aspects of mesoscale models which require special techniques and parameterizations when modelling flow over complex terrain the basic concepts and limitations of various approaches are discussed and applications of models to specific problems are presented