applications of geochemistry in tsunami research a review abstract much progress has been made since the first published studies of tsunami deposits nearly 30 years ago geochemistry is now a much more widely used proxy in tsunami research mainly due to its increasingly recognised value in the identification of historical and or prehistorical deposits at times even providing the conclusive proof when other proxies are missing or equivocal but also its significance in environmental impact assessments following recent tsunamis the rapid advance in analytical techniques has also made it a more approachable and popular method as it is now often faster and cheaper here we provide a review of the applications of geochemistry including the techniques used as well as a database of studies that used chemical proxies in their investigation of recent and old events including onshore and offshore tsunami deposits chemical signatures are often used as markers of marine inundation either as salinity indicators where they can also allow the identification of the limit of tsunami inundation or tracers of the incorporation of marine sourced carbonates their applications as indicators of source material are nevertheless expanding thereby potentially providing additional information on the hydrodynamic processes associated with tsunami inundation although they are largely site specific the effects of post depositional changes in different climatic regimes are examined with a particular emphasis on water leachable components and implications for post event recovery of coastal ecosystems we demonstrate the usefulness of chemical proxies in studies of the geological record of tsunamis extending back thousands of years suggest new approaches and discuss limitations and existing knowledge gaps

earthquake generated tsunamis in the mediterranean sea scenarios of potential threats to southern italy italian civil defense project development of new technologies for the protection of the italian territory from natural hazards funded by the italian ministry of university and research

geoarchaeology confirms location of the ancient harbour basin of ostia italy abstract to the northwest of the ancient city of ostia the analysis of cores revealed a stratigraphic sequence which we interpret as the filling of a harbour basin this basin located at the west of the so called palazzo imperiale presents seven characteristics 1 the maximum depth is 6 m below the roman sea level this depth allowed any type of ship even heavy tonnage to access the harbour 2 a chronostratigraphic gap at 6 m below roman sea level suggests digging operations in the basin or subsequent dredging that have caused the loss of sedimentary archives 3 the filling consists of dark clays typical of a quiet environment but open to marine and river influences 4 the dates at the base of this sequence give a range between the 4th and the 2nd century bc 5 in the harbour sequence a facies change at 2 5 m under the roman sea level involves a change in the processes of sedimentation and or operation 6 no later than the beginning of the 1st century ad the thickness of the water column in the basin is less than 50 cm and seems to be caused by a massive siltation following a succession of floods of the tiber 7 this basin was thus already abandoned during the start up of portus

research aircraft observations and numerical simulations of a warm front approaching vancouver island abstract the mesoscale structure of the low level flow and the character of the turbulence are investigated for a warm front as it approached the prominent terrain of the pacific northwest in the vicinity of vancouver island flight level and airborne doppler radar measurements collected from a national oceanic and atmospheric administration p 3 research aircraft on 9 december 1995 during the coastal observation and simulation with topography experiment and high resolution numerical simulations performed with the naval research laboratory s nonhydrostatic coupled ocean atmosphere mesoscale prediction system coamps model have been used to document the warm front as it approached the coast and the structure of cool air trapped along vancouver island this air mass was capped by a flat thin transition zone of enhanced static stability and vertical wind shear the flow within the trapped air mass was oriented parallel to the terrain of vancouver island but appears to have been more an outflow from the s

the tiber river delta plain central italy coastal evolution and implications for the ancient ostia roman settlement geomorphologic stratigraphic faunistic palynological and carbon isotope analyses were carried out in the area of the tiber river mouth the results depict a complex palaeoenvironmental evolution

geochemical investigation of a sediment core from the trajan basin at portus the harbor of ancient rome a journal published by elsevier the attached copy is furnished to the author for internal non commercial research and education use including for instruction at the authors institution and sharing with colleagues other uses including reproduction and distribution or selling or licensing copies or posting to personal institutional or third party websites are prohibited in most cases authors are permitted to post their version of the article e g in word or tex form to their personal website or institutional repository authors requiring further information regarding elsevier s archiving and manuscript policies are encouraged to visit a b s t r a c t from the 1st century ad and for the duration of the roman empire the portus complex was the main harbor of rome its location on the tiber delta next to the tyrrhenian sea produced rapid environmental changes that together with historical vicissitudes largely determined the fate of the harbor we have assembled data on the mineralogy sedimentology geochemistry and ostracod populations of a sediment core drilled in the access channel of the hexagonal basin of trajan with the expectation that such a combined data set will shed new light on how the connections of the inland trajan basin with the tiber river the earlier claudius harbor on the nearby shoreline and the sea evolved through the centuries the data define four distinct periods which geochemistry characterizes by different conditions of salinity and oxygenation these in turn can be related to historical periods and events by means of 14

tsunami sedimentation associated with the lisbon earthquake of 1 november ad 1755 boca do rio algarve portugal a description is given of a distinctive marine deposit at boca do rio on the algarve coast of portugal it is proposed here that the sediment accumulation was deposited by the tsunami generated by the lisbon earthquake of 1 november ad 1755 the deposit exhibits sedimentary characteristics quite unlike other coastal sediment accumulations that are deposited by more moderate wave regimes these include laterally continuous sand layers chaotic pebble horizons large amounts of gravel sized shell debris and distinctive assemblages of marine microfossils a preliminary attempt is made here to use the empirical field and laboratory data to define more clearly the processes of coastal sedimentation that characterize tsunami runup the use of tsunami sediments as time synchronous marker horizons is also discussed

sediments deposited by the 2004 indian ocean tsunami along the malaysia thailand peninsula stratigraphy grain size distribution and foraminiferal assemblages of pre tsunami and tsunami sediment from the indian ocean tsunami at five sites along the malaysia thailand peninsula were analyzed to gain information on tsunami sediment source and deposition style between three and five stratigraphic units were identified at each site and contained between one and three fining upward sequences reflecting waning flow or pre backwash deposition coarser sand layers reflecting uprush high energy flow separated the fining upward sequences with the exception of one site sungai burong which contained a coarsening upward sequence all contacts between the pre tsunami and tsunami sediment were sharp or erosional medium and coarse sand dominated all of the tsunami sediment deposits and often contained shell fragments foraminiferal assemblages were able to differentiate pre tsunami sediment from tsunami sediment where no lithological or grain size distribution change was evident between two and four foraminiferal zones were identified at each of the five sites and provided estimates of sediment source and wave characteristics

windstorms along the western side of the washington cascade mountains part i a high resolution observational and modeling study of the 12 february 1995 event abstract this paper describes the leeside wind event of 12 february 1995 in which a swath of strong low level easterly flow with gusts to 35 40 m s 1 extended downwind of a major gap in the cascade mountains over the puget sound lowlands low level easterly flow approaching the olympics was decelerated to less than 5 m s 1 resulting in enhanced over 30 cm snowfall along the windward side of the barrier in addition to conventional synoptic observations high resolution data sources were utilized profilers on both sides of the cascades a wsr 88d doppler radar located in northern puget sound and nonhydrostatic model simulations down to 1 km resolution with the exception of underpredicting heavy snowfall to the east of the olympics many of the mesoscale features of this event were realistically simulated including cold air damming over eastern washington strong winds downwind of the gaps a mountain wake downstream of mount rainier and flow splitting around the olympics a major objective of th

the contribution of geochemistry to ancient harbor geoarcheology the example of ostia antica abstract once trapped in ancient harbor basins sediments form environmental archives that have been widely studied by geoarcheologists in recent decades especially to help reconstruct fluvio marine landscapes of the last millennia in some cases classic environmental markers cannot be used for this purpose either because of their scarcity in the sedimentary deposits or because analytical costs limit the resolution that can be achieved in order to remedy these shortcomings and to complement the more commonly used proxies elemental and isotopic geochemistry has been added to the geoarcheological toolkit here we show how to read the evolution of the paleo environmental dynamics in the water column of ostia antica rome s first maritime harbor using the geochemical and isotopic record of a 3000 year old sediment core drilled in the ancient harbor basin a comparison of the results obtained from ostia antica with those of other ancient mediterranean harbors reveals the nature of the main environmental processes operating during the formation of sedimentary deposits in harbor basins from this comparative approach it appears that the respective weight of each control factor is dependent on the coastal geomorphological context of the sites where the harbors were established since the discovery of the harbor of ostia antica in 2014 this method has provided the means for the first time to identify two distinct harbor basin regimes an initial marine dominated regime from the middle of the 4th c bc to the 3rd c bc and a later freshwater dominated regime up to the 2nd c bc more generally we observe the effects of the dynamics of the deltaic progradation of the tiber which very early on was subject to a hydro climatic component on the processes of alluviation of the harbor basin additionally and also for the first time in harbor geoarcheology pb isotope compositions measured specifically on uncontaminated sediments demonstrate their utility for both identifying the geological sources of the sediments of the tiber delta and discriminating finer from larger particles the present study further provides an opportunity to test the validity of two hypotheses recently put forward 1 that a series of three tsunamis is recorded in the harbor silts and 2 that an initial lagoon type harbor was constructed at ostia antica which later evolved into a fluvial harbor neither of these hypotheses are supported by the present data

demise of a harbor a geochemical chronicle from ephesus a b s t r a c t at the end of the first century bc ephesus became the roman capital of asia minor and the most important commercial religious and cultural center of the region in order to evaluate the status of anthropogenic fluxes in the port of ephesus a 12 m long sediment core drilled in the roman basin was investigated to shed light on the paleo environmental evolution of the harbor using grain size distri bution analysis 14 c ages major and trace element geochemistry and pb isotope compositions with the help of complementary sedimentological data and principal component analysis five distinct units were identified which together reflect the different stages of water history in the harbor among the major disruptive events affecting the port were earthquakes and military events both of which were partic ularly effective at destroying the water distribution system seasonal floods of the cayster river kucuk menderes were the major source of the silt that progres sively infilled the harbor silting in was further enhanced by the westward migration of the river mouth a single major disruptive event located at 550 cm core depth and heralding the development of anoxia in the harbor marks the end of the dynamic regime that otherwise controlled the harbor water throughout the roman empire period this remarkable event may correspond to a major disruption of the aqueduct system or to a brutal avulsion of the cayster river bed it clearly represents a major disturbance in the history of life at ephesus it is poorly dated but probably occurred during the reign of augustus or shortly after lead isotope and trace metal evidence suggest that in the four bottom units pollution was subdued with respect to other pb metal inputs presumably those from aqueducts and natural karstic springs near the top of the core which coincides with harbor abandonment and the more recent period anthropogenic pb contam ination is clearly visible in both pb abundances and isotopic compositions

benthic foraminiferal assemblages of the imperial harbor of claudius rome further paleoenvironmental and geoarcheological evidences this paper presents a paleoenvironmental reconstruction of historical development in the area of the ancient harbor of claudius based on micropaleontological and sedimentological data benthic foraminifera are reliable tools for this kind of research because they are sensitive to short time environmental changes induced by both natural and anthropogenic events by studying eight sediment cores collected from different sections of the harbor it was possible to reconstruct a comprehensive picture of the harbor complex qualitative and quantitative analysis of foraminiferal associations and sedimentological data along with radiocarbon dating were useful to identify three key intervals in the history of the coastal area where the harbor developed the first interval located at the bottom of all cores is characterized by a brackish water environment corresponding to the formation of the first deltaic cusp of the tiber river the second interval is characterized by the harbor activities that developed aft

the tsunami phenomenon abstract with human activity increasingly concentrating on coasts tsunamis from japanese tsu harbour nami wave are a major natural hazard to today s society stimulated by disastrous tsunami impacts in recent years for instance in south east asia 2004 or in japan 2011 tsunami science has significantly flourished which has brought great advances in hazard assessment and mitigation plans based on tsunami research of the last decades this paper provides a thorough treatise on the tsunami phenomenon from a geoscientific point of view starting with the wave features tsunamis are introduced as long shallow water waves or wave trains crossing entire oceans without major energy loss at the coast tsunamis typically show wave shoaling funnelling and resonance effects as well as a significant run up and backflow tsunami waves are caused by a sudden displacement of the water column due to a number of various trigger mechanisms such are earthquakes as the main trigger submarine and subaerial mass wastings volcanic activity atmospheric disturbances meteotsunamis and cosmic impacts as is demonstrated by giving corresponding examples from the past tsunamis are known to have a significant sedimentary and geomorphological off and onshore response so called tsunamites form allochthonous high energy deposits that are left at the coast during tsunami landfall tsunami deposits show typical sedimentary features as basal erosional unconformities fining upward and landward a high content of marine fossils rip up clasts from underlying units and mud caps all reflecting the hydrodynamic processes during inundation the on and offshore behaviour of tsunamis and related sedimentary processes can be simulated using hydro and morphodynamic numerical models the paper provides an overview of the basic tsunami modelling techniques including discretisation guidelines for appropriate temporal and spatial resolution as well as the nesting method furthermore the boussinesq approximation a simplification of the three dimensional navier stokes equations is presented as a basic theory behind numerical tsunami models which adequately reflects the non linear dispersive wave behaviour of tsunamis the fully non linear boussinesq equations allow the simulation of tsunamis e g in the form of n waves based on the various subtopics presented recommendations for future multidisciplinary tsunami research are made it is especially discussed how the combination of sedimentary and geomorphological tsunami field traces and numerical modelling techniques can contribute to derive locally relevant tsunami sources and to improve the assessment of tsunami hazards considering the individual pre history and physiogeographical setting of a specific region

correlation between foraminifera and sedimentary environments in recent estuaries of southwestern spain applications to holocene reconstructions a multivariate analysis of the foraminifera collected in three estuaries of southwestern spain guadiana piedras tinto odiel permits recognition of three main assemblages with spatial distribution depending on sedimentary environments grain size classes and salinity variations assemblage 1 trochammina inflata jadammina macrescens is typical of salt marsh deposits with high salinity variations and percentages of important silt assemblage 2 ammonia beccarii ammonia tepida astrononion stelligerum elphidium williamsoni includes the most abundant estuarine species with increasing densities from the channel margin to the subtidal channel assemblage 3 quinqueloculina seminulum elphidium crispum is mainly found in the sandy sediments of the subtidal channels located near the mouth with normal marine conditions these results and the sedimentological interpretation of seven drill cores collected in the domingo rubio channel tinto river allow reconstruction of the palaeogeographic changes of this small estuary in the last ca 6500 14 c years bp seven phases were distinguished with an evolution from an open marine bay to

an observational and modeling study of the interaction of low level southwesterly flow with the olympic mountains during coast iop 4 abstract this paper presents an observational and modeling study of the three dimensional flow and precipitation around the olympic mountains of northwest washington state for a case of relatively steady south southwesterly flow this study utilized data from coast iop 4 the fourth intensive observing period during the coastal observation and simulation with topography field experiment that took place during 9 10 december 1993 one of the most important data sources was the noaa p 3 aircraft which provided flight level data reflectivity and doppler winds as it flew around the olympics features that were mapped successfully with the noaa p 3 included flow splitting around the windward pressure ridge strong southeasterlies to approximately 25 m s 1 northeast of the olympics caused by downgradient acceleration into the lee trough the rapid transition from strong southeasterlies to lighter easterlies 5 10 m s 1 in the strait of juan de fuca strong downslope flow and a hydraulic jump like transiti

multiple precipitation mechanisms over mountains observed by airborne doppler radar during map iop5 abstract this study uses airborne doppler radar measurements from the special observing period of the mesoscale alpine programme map to document the detailed airflow and precipitation structure over the mountainous regions near the border of northeastern italy and slovenia as a cold frontal system moved eastward and encountered the eastern alps on 4 october 1999 during map iop5 in contrast to previously documented map cases the environmental conditions associated with this case are characterized by a deep layer of strong convective instability in the lower troposphere and by a cold northeasterly continental flow coming down from the mountains the so called bora wind along the southeastern alps over the study region there are two primary mountain barriers the julian alps oriented roughly west east with a peak mountain height of 2500 m and a significant variation in terrain height along its length and the other the dinaric alps a relatively lower mountain range oriented northwest southeast

geoarchaeological investigations of a prominent quay wall in ancient corcyra implications for harbour development palaeoenvironmental changes and tectonic geomorphology of corfu island ionian islands greece abstract in antiquity the harbour city of corcyra modern corfu was a prevailing naval power in the mediterranean and had several harbours to host a considerable fleet today these harbours are totally or partly silted and concealed under modern urban infrastructure comprehensive geoarchaeological studies were conducted on the northeastern fringe of the analipsis peninsula where excavations have revealed the archaeological remains of a massive quay wall pierri and arion sites these remains are located east of known ancient harbour structures that belong to the alkinoos harbour our study aimed to reconstruct the palaeoenvironmental setting of the harbour facilities at the pierri site including the analysis of the local sedimentary record in order to detect and differentiate natural and man made triggers that caused environmental shifts at the pierri site we found geoarchaeological evidence for an ancient harbour basin related to the prominent quay wall associated harbour sediments indicate a protected harbour which was developed from an open shallow marine environment most probably by the construction of breakwaters harbour deposits were dated using radiocarbon analyses and diagnostic ceramic fragments to the 4 th to 3 rd cent bc this is in good agreement with the age of the harbour installations as such archaeologically assigned to the classical and hellenistic period the pierri site was possibly in function as a harbour facility even before the 4th cent bc in any case it was strongly hit by an earthquake and associated tsunami event during classical to hellenistic times by this event the harbour was uplifted and covered by event deposits so that it was not usable any more it was subsequently buried by anthropogenic and colluvial sediments overall the pierri coastal archive allowed to identify three distinct tsunami landfall events namely before 2483 2400 cal bc event i after 2483 2400 cal bc and before 370 214 cal bc event ii and during classical to hellenistic times most probably between the 4 th and 3 rd cent bc event iii another tsunami event event iv potentially hit the site when it was dry land ages of tsunami events i ii and candidate tsunami iv are consistent with tsunamis known from the coasts of western greece and southern italy and where thus classified as supra regional tele events event iii was identified as associated to a local earthquake and tsunami by which corfu island was uplifted and at the same time tilted with a vertical offset of 1 74 m from w to e

dating tsunami deposits present knowledge and challenges abstract dating approaches for fine sediment tsunami deposits can be divided into two categories 1 dating directly using materials from within a tsunami deposit and 2 dating indirectly using materials from above and below it for the former optically stimulated luminescence osl dating has a possible advantage in that is can directly date the burial age of sediments laid down by a tsunami however because of methodological limitations osl dating cannot always provide a reliable age although 14c and u th dating of reworked material from within a tsunami deposit are possible means of determining the age of the event the results merely represent a maximum age of deposition for these reasons dating is commonly achieved indirectly from 14c dates taken from samples in sections immediately above and below a tsunami deposit however indirectly dated results do not provide a precise timing of the event therefore there are distinct limitations in the ability to obtain high precision dating of past tsunamis recent methodological developments including the application of bayesian statistical analysis to radiocarbon dating results and the selection of appropriate dating materials has significantly improved the accuracy of age determination by reducing errors this review presents several methodological improvements that have enhanced tsunami deposit age estimation the most important points for a more precise tsunami age estimation are the numbers of 14c samples dated coupled with the use of bayesian statistical analysis these points are applicable not only to tsunami deposits but also to many other past geohazard events

human impact on holocene sediment dynamics in the eastern mediterranean the example of the roman harbour of ephesus during the past millennia many erosion and accumulation processes have been modified by anthropogenic impact this holds especially true for the environs of ancient settlements and their harbours along the mediterranean coasts our multi proxy investigations in the roman harbour and the harbour canal of ephesus western turkey reveals that humans have significantly triggered soil erosion during the last three millennia since the eighth century bc and especially since the hellenistic period a high sed imentation rate indicates fast alluviation and delta progradation of the kucuk menderes deforestation agriculture especially ploughing and grazing especially goats were the main reasons for erosion of the river catchment area one consequence was significant siltation of the hellenistic roman harbour basin this sediment trap archives the human impact which was strongly enhanced from hellenistic roman to byzantine times second first centuries bc to the sixth seventh centuries ad evidenced by high sedimentation rates raised values of heavy metal contaminations lead pb copper cu the occurrence of fruit tree pollen and of intestinal parasites from the middle to the end of the first millennium ad the influence of ephesus declined which resulted in a decrease of human impact studies of several ancient settlements around the mediterranean sea tell a comparable story they also confirm that during their most flourishing periods the human impact totally overprinted the climatic one to detect the latter geo bio archives of relatively pristine areas have to be investigated in detail

wind induced salt wedge intrusion in the tiber river mouth rome central italy the wind effect on river water quality was illustrated by means of thermohaline measurements carried out in the tiber river in may 2012 the survey was carried out using a boat in stations located in the two tiber branches fiumara grande and traiano canal thermohaline variables salinity and temperature were used to describe the water type patterns and to define the salt wedge position although the river flow rate was rather high saltwater intrusion happened wind data suggested that the more probable cause of salt wedge intrusion was the wind action especially wind speeds higher than 4 m s are able to dominate the sea current at surface layers determining an increase in the sea level therefore westerly winds determined a seawater inflow in the river mouths

the river harbour of ostia antica stratigraphy extent and harbour infrastructure from combined geophysical measurements and drillings abstract we performed a combined geophysical and geoarchaeological survey of the harbour of ancient ostia italy to investigate the extent of the former harbour basin the sedimentary infill and possible building remains around the harbour besides geoarchaeological results the paper highlights the advantage of combining vibracore drilling with different geophysical prospection methods which are sensitive to different physical soil parameters geophysical methods applied were electrical resistivity tomography ert ground penetrating radar gpr and seismics with shear and compressional waves the extent and shape of the harbour basin were determined by ert profiling the ert profiles were compiled into a 3d model showing that the early lagoonal harbour basin was at least 100 m 50 m wide its southern border was confirmed by gpr measurements clearly imaging the former land water transition and the onset of ancient onshore building construction at its eastern border a consolidated horizon could be mapped in 2 3 m depth by compressional wave tomography this horizon most likely represents a cemented ramp a small part of which had been excavated in a previous study the sedimentary fill of the former harbour basin was investigated by a combination of vibracoring ert and seismics the ert profiles serve for inter and extrapolating the vibracore stratigraphy from the coring locations over the whole harbour area it turned out that one sedimentary unit which is important for the harbour development could not be resolved by ert but clearly shows up in seismic velocity depth profiles instead it is a thin coarse grained high energy layer in 1 2 m depth which was caused by a tsunami according to a previous study this layer separates two harbour phases an older lagoonal harbour phase underneath and a younger fluvial harbour phase above it the high energy layer represents a thin band of 100 increased shear wave velocity compared to the more fine grained layers in which it is embedded this study is the first to show that tsunami type sedimentary layers may be mapped by shear wave profiling

palynology and ostracodology at the roman port of ancient ostia rome italy new detailed palynological and ostracodological analyses together with texture data from a sediment core drilled in ostia antica confirm the existence of the ancient ostia harbour and its location by the tiber river using the different proxies analysed in this work and chronologically framing the sediment record with three ams radiocarbon dates four phases have been singled out pre harbour harbour bay under fluvial influence more protected harbour basin and post harbour phase ostracodology is used to reconstruct the marine versus freshwater influence in the basin palynology is used to reconstruct the plant landscape and the surrounding environment phases with low pollen concentration and expansions of npps suggest soil erosion and are alternated with quieter ones where human impact was very clear deciduous oaks typical of coastal plain forests are the main taxon during the harbour phases the occurrence of riparian trees increases in periods with low pollen concentration high npps and very high pine percentages these should be the periods in which important sediment inputs inside the harbour basin arrived and could be the expression of intense flooding phases the comparison between the ostracod assemblages recovered in the two cores and has led to speculate a complex harbour structure a separation could explain the micropalaeontological differences between the cores thus we suggest that a pier must have been built in order to protect the inner harbour from the marine influence and to unload the goods transported by the big ships

evaluation of tsunami flooding using geomorphologic evidence abstract whatever the generating mechanism of a tsunami may be this event can discharge destructive energy along coastal areas and produce widespread inundation the presence of large boulders along rocky coasts could be a useful indicator to understand the extent of the impact of past tsunami floods a detailed study of the deposited boulder features size shape and rock density and their initial position prior to the transport is extremely important when reconstructing the possible morphodynamic scenario s applying the appropriate equations is important when aiming to assess the maximum extent of flooding the integration of morphological and hydrodynamic data allows for an estimation of the water level during the tsunami event responsible for boulder transport moreover it is possible to calculate how far the impacting wave flooded inland this is a function of the wave parameters and of the degree of roughness of the flooded terrain that is expressed by the manning number to evaluate its probable average value experimental data computer simulations and post tsunami surveys have been performed in two sectors of the southern apulia coastline characterised by the presence of tsunami boulder fields and or ridges the surveys in each site have allowed for the calculation of the boulder sizes the estimation of their pre transport location and the extent of inland flooding data have been processed using a geographic information system gis as a result a flooding map useful in planning future possible actions for coastal area use has been produced

coastal sedimentation associated with the december 26 2004 tsunami in lhok nga west banda aceh sumatra indonesia abstract with wave heights of 30 m and runups reaching 50 m a s l and 6 km inland the december 26 2004 tsunami in sumatra was one of the largest tsunamis in recorded human history in this paper we present a description of the event in the lhok nga bay west coast of banda aceh and an interpretation of the tsunami sand deposits mostly based upon grain size analysis the 3 5 km long transect of lampuuk displays two landward fining thinning and sorting sequences the thickest cross sections of the first sequence of deposits 0 1 5 km inland suggest a deposition by three consecutive runups inflows and a final backwash return flow or outflow from 1 5 to 3 5 km inland the record is dominated by the second and highest wave 15 30 m normally graded couplets or triplets of layers were used to identify the runup of each wave the topmost layers interpreted as the backwash deposition describe a seaward sequence of increasing mean grain size and decreasing degree of sorting the local effects of the topography could be identified thickest deposits in the topographic lows 50 80 cm great spatial variations in thickness and upper laminated texture when the sedimentation was limited by steep slopes landward coarsening and very poor sorting at the wave breaking point bimodal grain size distributions reflecting different sources of sediments finally by coupling the longitudinal and vertical trends of the 26 cross sections we propose a model of sediment transport and deposition in a large tsunami wave

an intercomparison of t rex mountain wave simulations and implications for mesoscale predictability abstractnumerical simulations of flow over steep terrain using 11 different nonhydrostatic numerical models are compared and analyzed a basic benchmark and five other test cases are simulated in a two dimensional framework using the same initial state which is based on conditions during intensive observation period iop 6 of the terrain induced rotor experiment t rex in which intense mountain wave activity was observed all of the models use an identical horizontal resolution of 1 km and the same vertical resolution the six simulated test cases use various terrain heights a 100 m bell shaped hill a 1000 m idealized ridge that is steeper on the lee slope a 2500 m ridge with the same terrain shape and a cross sierra terrain profile the models are tested with both free slip and no slip lower boundary conditions the results indicate a surprisingly diverse spectrum of simulated mountain wave characteristics including lee waves hydraulic like jump features and gravity wave breaking the vertical v

foraminifera as holocene environmental indicators in the south alligator river northern australia samples of plankton surface sediments and holocene deposits from the south alligator river an energetic macrotidal river in northern australia are examinedto evaluate the usefulness of estuarine foraminifers for palaeoenvironmental interpretation of sediments deposited in tropical macrotidal conditions although marine and estuarine foraminifers in the estuarine channel are mixed by strong tidal currents there are significant trends along the 80 km length of the tidal river the relative proportions of marine andporcellaneous taxa d ecrease upstream from the mouth but hyaline taxa andthose with brackish affinities increase upstream foraminifers in intertidal sediments have distinctly different assemblages in the uppermost intertidal mid tidal mangrove lower intertidal and subtidal zones in addition to the effects of tidal mixing preserved thanatacoenoses are affected by selective dissolution and or pyritisation within the sediment bodies despite the effects of adverse taphonomic factors foraminiferal assemblages preserved in drill cores provide an accurate guide to original depositional environments intertidal subtidal brackish estuarine coastal marine in mid holocene sediments in the south alligator area foraminifers are found to improve the precision of previous palaeoenvironmental reconstructions made on the basis of sedimentary facies and pollen analyses r 2001 elsevier science ltdandinqua all rights reserved

sequence stratigraphy and depositional setting of the tiber delta integration of high resolution seismics well logs and archeological data abstract using archeological evidence radiocarbon data well logs and high resolution seismic profiles we applied sequence stratigraphic analysis to sediments deposited during the last glacio eustatic cycle on the tyrrhenian continental margin embracing the tiber river months these sediments form a high frequency sequence of fifth order that has developed over the last 20 000 yr since the last lowstand hereafter referred to as the tiber depositional sequence tds the tds is still evolving and lies on a type 1 sequence boundary that has been identified both on the shelf and below the present delta plain this sequence consists of lowstand transgressive and highstand systems tracts the lowstand deposits are not present on the shelf but are found on the continental slope where they constitute the last progradation set of the continental margin a network of gullies active when the river mouth was at the shelf break is present within the lowstand deposits the transgressive systems tract tst deposits lie directly on the basal unconformity landwards the tst is represented by a retrogradational parasequence set of fluvial coastal barrier lagoon and lagoonal delta facies seaward on the shelf these parasequences merge into a seismically transparent deposit that forms a condensed section the flooding surfaces that bound the parasequences are marked by peat layers that were dated by 14c the radiometric ages were used to draw a carve of sea level rise for the last 11 000 yr the top of the transgressive systems tract maximum flooding surface is represented by the last peat layer which was formed about 4700 5000 yr bp and buried 4 5 m below the present upper delta plain the highstand systems tract is made up of deposits of the present tiber wave dominated delta i e upper and lower delta plain delta front and prodelta slope the aligned beach ridges mark the position of the prograding coastline which for the last 2500 yr can be dated by archeological and historical data the recent very fast progradation of the tiber delta during the last 500 years is consistent with historical data on floods of the city of rome and the suspended load of the tiber river

a source to sink compositional model of a present highstand an example in the low rank tiber depositional sequence latium tyrrhenian margin italy abstract our source to sink compositional model of sediment distribution in the present highstand of the tiber depositional sequence has important implications for sediment source lithology generation transport and deposition in the tiber river system sand compositional trends reflect provenance mixing anthropic intervention and the effects of local autogenic factors in continental to marine depositional environments fluvial feldspatho quartzo lithic sand results from the contribution of the major tributaries of the tiber drainage basin which can be divided into two sub basins separated by the corbara dam built in the 1950s upstream drainage basin sand has a siliciclastic sedimentary lithic signature whereas carbonate and volcanic lithic fragments dominate downstream drainage basin sand downstream sand is further modified in the coastal environment by hydraulic sorting and mixed with detritus derived from the recycling of coastal dune sand and altered volcaniclastic paleosols the latter are associated with lower course floodplain and channel deposits which produce a quartzo feldspatho lithic sand sediment grain size zonation in the marine environment is influenced by coastal hydrodynamics which in turn produce two detrital populations with distinct compositional signatures and hydraulic behavior coarser minerals essentially pyroxene phenocrysts and finer feldspar grains are progressively concentrated in higher energy and lower energy environments respectively biogenic continental shelf and slope deposits off the tiber river mouth show very little riverine influence this study of the last highstand system tract in the tiber depositional sequence clarifies the effects of hydraulic sorting grain size dependence and sediment reworking in controlling the final composition of modern sand this knowledge can be used to better understand detrital modes of ancient sedimentary successions

a systematic review of geological evidence for holocene earthquakes and tsunamis along the nankai suruga trough japan the nankai suruga trough the subduction zone that lies immediately south of japan s densely populated southern coastline generates devastating great earthquakes magnitude 8 characterised by intense shaking crustal deformation and tsunami generation forecasting the hazards associated with future earthquakes along this 700 km long fault requires a comprehensive understanding of past fault behaviour while the region benefits from a long and detailed historical record palaeoseismology has the potential to provide a longer term perspective and additional crucial insights in this paper we summarise the current state of knowledge regarding geological evidence for past earthquakes and tsunamis along the nankai suruga trough incorporating literature originally published in both japanese and english and enhancing available results with new age modelling approaches we summarise and critically evaluate evidence from a wide variety of sources palaeoseismic evidence includes uplifted marine terraces and biota marine and lacustrine turbidites liquefaction features subsided marshes and tsunami deposits in coastal lakes and lowlands while 75 publications describe proposed evidence from 70 sites only a limited number provide compelling well dated evidence the best available records enable us to map the most likely rupture zones of twelve earthquakes that occurred during the historical period this spatiotemporal compilation suggests that the 1707 ce earthquake ruptured almost the full length of the subduction zone and that earthquakes in 1361 ce and 684 ce may have been predecessors of similar magnitude intervening earthquakes were of lesser magnitude highlighting the variability in rupture mode that characterises the nankai suruga trough intervals between ruptures of the same seismic segment range from 450 years during the historical period over longer timescales palaeoseismic evidence suggests intervals between earthquakes ranging from 100 to 700 years however these figures reflect a range of thresholds controlling the creation and preservation of evidence at any given site as well as the genuine intervals between earthquakes at present there is no geological data that suggest the occurrence of a larger magnitude earthquake than that experienced in 1707 ce however few studies have sought to establish the relative magnitudes of different earthquake and tsunami events along the nankai suruga trough alongside the lack of research designed to quantify the maximum magnitude of past earthquakes we emphasise issues over alternative hypotheses for proposed palaeoseismic evidence the paucity of robust chronological frameworks and insufficient appreciation of changing thresholds of evidence creation and preservation over time as key issues that must be addressed by future research

the role of foraminifera as indicators of the late pleistocene holocene palaeoclimatic fluctuations on the deltaic environment the example of tiber delta succession tyrrhenian margin italy abstract the palaeoclimatic and palaeoenvironmental reconstruction of the last 39 0 kyr of the central tyrrhenian shelf are presented in this paper micropalaeontological sedimentological and stable isotopic data integrated by radiocarbon dates were determined from three cores drilled in the tiber delta sequence tds which constitutes one of the most complete late quaternary high frequency depositional sequences in the mediterranean area short period climate variations that induced short period events caused changes in the tiber run off and increased the sediment supply and grain size in the delta system the three cores with different thicknesses record all the system tracts forming the tds three intervals corresponding to the early and late lowstand transgressive and highstand system tracts tst and hst were recognised the first is characterised by shoreface inner shelf deposits and corresponds to a general cooling period characterised by short warmer periods approximately 1 0 kyr confirming the climatic variability of mis 3 mis 2 a very condensed deposition affected the second interval which is characterised by a very low sedimentation rate corresponding to the tst of tds the third interval corresponding to holocene shelf deposits shows small climatic oscillations that mark an enhanced seasonality typical of the modern tyrrhenian regime at the millennial scale two warm intervals copper age and late bronze age ii century ac alternating with two cold humid intervals bond cycle b3 rcc 4 2 3 8 kyr bp of mayewski events and the little ice age have been recognised

the transition from wave dominated estuary to wave dominated delta the late quaternary stratigraphic architecture of tiber river deltaic succession italy abstract this paper presents a detailed description of the stratigraphic architecture of the late pleistocene holocene tiber delta succession in order to document the passage from wave dominated estuary to wave dominated delta in the broader context of late quaternary sea level fluctuations this succession constitutes a sequence stratigraphic unit known as tiber depositional sequence tds which was deposited during the last glacial interglacial cycle last 120 ka our study is based on the examination of an enormous amount of data derived from the stratigraphy of about 300 wells petrographical and paleontological data foraminifera ostracoda pollen and plant macrofossils 14 c dating and from the integration of geomorphological and geoarcheological data recently a 100 m deep core pesce luna well was studied through a multidisciplinary approach and a detailed description of sedimentary facies foraminifer and ostracod assemblages pollen and 14 c dating is presented in this paper the new data allowed to produce three new correlation panels and to describe in more detail with respect to previous interpretations the stratigraphic depositional architecture of the tds which internally shows the preservation of sediment deposited during the early and late lowstand the transgressive and the highstand systems tracts alluvial and coastal depositional systems characterize the early lowstand phase of the tds which developed during the eustatic sea level fall between about 120 and 30 26 yr bp during the late lowstand phase which is characterized by stillstand and slow eustatic sea level rise a prograding delta and an aggrading incised valley fluvial fill developed the tiber incised valley was transformed into a wave dominated estuary during the transgressive phase tst whereas a coastal shelf sedimentation took place during the subsequent highstand phase hst this study confirms the lithofacies distribution resulting from transgression and infilling of the wave dominated estuaries but also shows how the transition to a wave dominated delta prograding at the time of sea level highstand occurred changes in sediment input climatic variations and more recently human activities played a major role in the development of the tiber delta during the last 20 000 yr bp in the last 3000 years a relationship between progradational phases of the delta and flood events of the tiber river has been highlighted suggesting also the formation and merging of barrier spits to the mainland

the effect of mesoscale mountain over the east indochina peninsula on downstream summer rainfall over east asia abstractthe mesoscale mountain over the east indochina peninsula named annam cordillera plays a key role in shaping the south china sea scs summer climate in both the atmosphere and the ocean however its effect is not limited to the scs ensemble simulations using a high resolution regional atmospheric model with or without the mountain reveals that the annam cordillera has a significant impact on regional climate as far as 3000 km over south and east china and western northwest pacific wnp by blocking lifting the warm and moist air from the bay of bengal the annam cordillera forces upward motion and precipitation on the windward side and subsidence on the leeward side and a low level southwesterly jet to the southeast tip of the indochina peninsula over the scs the latter gives rise to coastal upwelling and cold sea surface temperature sst filaments in the western scs reducing surface sensible and latent heat fluxes and thus suppressing convection over the scs heating associated with the

a geochemical and sedimentological perspective of the life cycle of neapolis harbor naples southern italy since the discovery of the ancient harbor of naples in 2004 during construction work on an underground railway geoarchaeological studies undertaken on the archaeological excavation have revealed the main stratigraphic and paleo environmental levels of the harbor site near the piazza municipio however knowledge of the dynamics and paleoenvironmental changes in the water column of the harbor as well as the processes of transport and deposition of sediments that led to siltation and infilling of the harbor basin has been lacking due to the absence of high resolution data to fill these gaps we have undertaken a threedimensional study longitudinal transverse and vertical of the harbor deposits by carrying out geochemical and sedimentological analyses of four stratigraphic sections of the archaeological excavation the results show that after a phase of relative calm during the first half of the 1st c ad siltation of the harbor progressed exponentially up to the 5th c ad when dredging operations were carried out to obtain a water level sufficient for the development of maritime and harbor activities we attribute this acceleration of siltation to a combination of climatic anthropic and volcanic factors volcanic activity was responsible for a high energy tsunami type event during the eruption of vesuvius in 79 ad from the 5th c ad onwards the harbor basin of neapolis does not appear to have been functional as evidenced by its transformation into a lagoon following coastal progradation the last stage of infilling was the development of a flood dominated fan delta under the combined influences of climatic cooling in the early medieval cool period and agro pastoral activities in the catchment area of the harbor several generations of paleo channels containing flash flood deposits as well as sheet wash from sheet floods are indicative of high environmental instability in this period

review of magnetic field monitoring near active faults and volcanic calderas in california 1974 1995 abstract differential magnetic fields have been monitored along the san andreas fault and the long valley caldera since 1974 at each monitoring location proton precession magnetometers sample total magnetic field intensity at a resolution of 0 1 nt or 0 25 nt every 10 min data samples are transmitted via satellite telemetry to menlo park ca for processing and analysis the number of active magnetometer sites has varied during the past 21 years from 6 to 25 with 12 sites currently operational we use this network to identify magnetic field changes generated by earthquake and volcanic processes during the two decades of monitoring five moderate earthquakes m5 9 to m7 3 have occurred within 20 km of magnetometer sites located along the san andreas fault and only one preseismic signal of 1 5 nt has been observed during moderate earthquakes coseismic magnetic signals with amplitudes from 0 7 nt to 1 3 nt have been identified for 3 of the 5 events these observations are generally consistent with those calculated from simple seismomagnetic models of these earthquakes and near fault coseismic magnetic field disturbances rarely exceed one nanotesla these data are consistent with the concept of low shear stress and relatively uniform displacement of the san andreas fault system as expected due to high pore fluid pressure on the fault a systematic decrease of 0 8 1 nt year in magnetic field has occurred in the long valley caldera since 1989 these magnetic field data are similar in form to observed geodetically measured displacements from inflation of the resurgent dome a simple volcanomagnetic model involving pressure increase of 50 mpa a at a depth of 7 km under the resurgent dome can replicate these magnetic field observations this model is derived from the intrusion model that best fits the surface deformation data

airborne doppler observations of a landfalling cold front upstream of steep coastal orography abstract this study uses airborne doppler radar observations to describe the mesoscale structure and evolution of a cold frontal system as it made landfall on the mountainous coast of oregon and northern california on 1 december 1995 during the coastal observations and simulations with topography experiment this section of coastline constitutes a steep approximately two dimensional north south oriented orographic barrier the front exhibited a northeast southwest orientation and thus intersected the axis of high terrain at an acute angle the along barrier pressure gradient and low level winds increased with time along the coastal zone and reached a maximum as the front made landfall stably stratified prefrontal flow was strongly blocked by the orography resulting in a confluent transition from pervasive southwesterly winds offshore to a narrow zone of accelerated south southwesterly flow near the coast where wind speeds approached 30 m s 1 at a height of 750 m above mean sea level postfrontal flow

the storegga slides evidence from eastern scotland for a possible tsunami abstract the second storegga slide on the continental slope off western norway has been dated at between 8000 and 5000 yrs b p a prominent sand layer in flandrian holocene deposits along the coast of eastern scotland and dated at approximately 7000 yrs b p may have been deposited by a tsunami generated by the slide the altitude and stratigraphy of the layer allow estimates to be made of the magnitude of the earthquake which initiated the slide

plant landscape and environmental changes recorded in marginal marine environments the ancient roman harbour of portus rome italy abstract the interpretation of past environment changes in coastal marshes river mouths and drainage channels connecting fresh to salt water bodies is a difficult task since several factors must be considered such as the variable influence of climate sea level changes coastline variations and changes in the river discharge it is even more difficult if this attempt is carried out in basins and channels of an ancient harbour used for centuries connected to the sea and to a river this is the case of the ancient harbour of rome located in the tiber delta area which had a prominent role during the imperial age in the mediterranean a town named portus arose in the vicinity and although sacked many times by barbarians was still very important during medieval times the romans managed the harbour the city and the surroundings and the impact on the environment must have been very strong a multi proxy approach was used to characterize and date environment and landscape changes in the ancient port of rome area from the 1st century to the 15th century ad plant macrofossil results have been integrated not only with pollen and microcharcoal but also with the tiber river bi millennial record available in literature this integration used to improve the chronological framing of the cores was carried out using ostracod analyses micro crustaceans commonly occurring in marginal marine environments and widely used for palaeoenvironmental reconstructions in particular the ability of some species to live within specific salinity ranges has been a precious tool to identify the hydrological setting of the depositional environment the cores recovered allowed recognition of two different sedimentary sequences the older shows the silting of the harbour during the first centuries and the younger records the sedimentation that occurred between the 4th and the 15th century ad this multi proxy approach applied to the study of plant remains indicates that 1 the human impact was lower during the first centuries ad than during late antiquity and middle ages or that 2 clues of human presence were easier to detect in a closed marshy area than in an open harbour the correlations between macroremains pollen percentage and concentration freshwater brackish water and salt water ostracods and the frequencies of tiber river floods during a 1500 year time span link some environmental changes and the silting of the harbour to the variations in hydrological regime of the tiber river

sedimentation and hydrodynamic processes associated with the tsunami generated by the 1755 lisbon earthquake abstract an unusual sedimentary horizon believed to have been deposited by the tsunami associated with the 1755 lisbon earthquake has been identified at boca do rio in southern portugal this horizon marks a distinct sedimentological and micropalaeontological break from the deposits enclosing it the sedimentary characteristics of the horizon which consists of several distinct sub units vary greatly in both vertical and horizontal section detailed textural analysis through vertical sections of these sub units shows abrupt changes in particle size characteristics the highly variable nature of the horizon appears to be due to rapid variation in the hydrodynamic characteristics of the depositional event the lowermost section of the deposit appears to have been deposited from a highly turbulent water mass which was able to transport gravel sized clasts as well as gravel sized mud balls eroded from underlying material the water mass rapidly lost energy leading to the deposition of predominantly sand silt and clay particles sharp breaks in textural characteristics are likely to be due to changes in current direction caused by wave reflection or swash backwash interference the main sources of sand sized material within the deposit are the seaward barrier beach foredune system the tsunami deposit at boca do rio shares many of the sedimentary characteristics of tsunami deposits from other sites around the world

tsunami sediments and their foraminiferal assemblages abstract tsunami hazard assessment begins with a compilation of past events that have affected a specific location given the inherent limitations of historical archives the geological record has the potential to provide an independent dataset useful for establishing a richer chronologically deeper time series of past events recent geological studies of tsunami are helping to improve our understanding of the nature and character of tsunami sediments wherever possible geologists should be working to improve the research tool kit available to identify past tsunami events marine foraminifera single celled heterotrophic protists have often been reported as present within tsunami deposited sediments but in reality little information about environmental conditions and by analogy the tsunami that deposited them has been reported even though foraminifera have an enormous capacity to provide meaningful palaeo environmental data here we review what foraminifera are describe their basic form and significance summarise where they have been reported in tsunami sediments and identify what can be learnt from them we review the gaps in our understanding and make recommendations to assist researchers who examine foraminiferal assemblages in order to enhance their use within tsunami geology

palaeotsunami deposits at the tiber river mouth ostia antica italy do they really exist abstract in this paper we test the recent hypothesis of the occurrence of five to seven tsunami generations that would have struck the ancient harbour basin of ostia italy and the lower channel of the tiber river during the last three millennia because these steady disaster events would have deep implications on our knowledge of the history of rome we reviewed the pluridisciplinary data available at the tiber river mouth considering sedimentological geomorphological micropalaeontological geochemical chronological and historical evidence there is currently no conclusive palaeoenvironmental evidence to suggest past tsunami inundations near ostia river mouths are not the best context in which to identify tsunami deposits high fluvial and coastal mobility generated by regular floods and storms hardly record single high energy events hee from floods storms or tsunamis sediments are regularly reworked at the river mouth both in the river channel and on the close shoreface mixed fluvial and marine influences and the seasonal formation of a salt wedge at the mouth of the tiber create specific estuarine assemblages for micro and macrofauna the layer called high energy event 1 hee 1 on the palaeo shoreface close to the river mouth and hee 4 5 in the point bars of the tiber channel are most probably layers reworked several times by fluvio coastal events storms and or floods hee 3 sealing the republican harbour of ostia is clearly related to flood deposits complementary analyses would be necessary to definitively identify the origins of the hee 2 and hee 7 in the harbour and hee 6 in the palaeochannel or floodplain based on the data available we show how other processes than tsunami inundations could be just as accountable for these coarse grained sediment layers storm deposit flood deposit or riverbank deposit this review puts into question the use of pluridisciplinary proxies to identify palaeotsunami deposits in addition we demonstrate how high pb concentrations constitute a robust proxy to definitively refute the presence of palaeotsunami deposits as such this study will be beneficial to a large community of specialists in coastal research

the climatology of small scale orographic precipitation over the olympic mountains patterns and processes the climatology of small scale patterns of mountain precipitation is poorly constrained yet important for applications ranging from natural hazard assessment to understanding the geologic evolution of mountain ranges synthesizing four rainy seasons of high resolution precipitation observations and mesoscale model output from the penn state ncar mm5 reveals a persistent small scale pattern of precipitation over the 10 km wide 800 m high ridges and valleys of the western olympic mountains washington state usa this pattern is characterized by a 50 70 excess accumulation over the ridge crests relative to the adjacent valleys in the annual mean while the model shows excellent skill in simulating these patterns at seasonal time scales major errors exist for individual storms investigation of a range of storm events has revealed the following mechanism for the climatological pattern regions of enhanced condensation of cloud water are produced by ascent in stable flow over the windward slopes of major ridges synoptically generated precipitation grows by collection within these clouds leading to enhanced precipitation which is advected by the prevailing winds instances of atypical patterns of precipitation suggest that under certain conditions during periods with a low freezing level or convective cells fundamental changes in small scale patterns may occur however case studies and composite analysis suggest that departures from the pattern of ridge top enhancement are rare the basic patterns and processes appear robust to changes in temperature winds and background rainfall rates copyright 2008 royal meteorological society

palaeoenvironmental evolution of the ancient harbor of lechaion corinth gulf greece were changes driven by human impacts and gradual coastal processes or catastrophic tsunamis abstract the corinth gulf central greece is one of the most rapidly widening tectonic rifts on earth where large earthquakes with magnitudes of up 7 0 have been documented not only by instrumental records but also assessed from historical reports extending back to the 5th century bce several of these earthquakes were associated with tsunamis particularly in the western part of the gulf of particular interest is the ancient harbor of lechaion in the eastern side of corinth gulf we reexamine the hypothesis that lechaion was hit by high energy tsunami waves in the 8th 6th century bce 1st 2nd century ce and during the 6th century ce on the basis of sedimentological seismotectonic archaeological and historical data completed with field observations we support that there is no evidence for tsunami impact in lechaion local stratigraphy and environmental changes are rather interpreted by human impacts and gradual coastal processes such interpretations confirm that the tsunami potential in the east corinth gulf is relatively low

numerical simulations of a landfalling cold front observed during coast rapid evolution and responsible mechanisms abstract this paper identifies mechanisms that led to the observed rapid evolution of a landfalling weak cold front along the steep mountainous northern california coast on 1 december 1995 this event was simulated down to 3 km horizontal grid spacing using the pennsylvania state university ncar mesoscale model version 5 mm5 the mm5 simulation reproduced the basic features such as the timing location and orientation of the cold front and associated precipitation evolution as well as the tendency for enhanced precipitation to extend 50 100 km upwind of the coastal barrier with the heaviest amounts occurring over the windward slopes 0 20 km inland locally however the model underestimated the magnitude of the prefrontal terrain enhanced flow by as much as 30 since the simulated low level static stability was weaker than observed the mm5 simulations illustrate the complex thermal wind and precipitation structures in the coastal zone upstream flow blocking by the steep coastal terrain led to

palaeotsunami deposits a new zealand perspective abstract over the past few years geological investigations of coastal sediments in new zealand have provided evidence of past tsunami the identification of palaeotsunami deposits is helping to increase our knowledge about the sources magnitude and frequency of these events this paper briefly outlines both the key diagnostic characteristics used in new zealand to identify palaeotsunami deposits and the emerging findings related to recent research