Zeitschriftenartikel: „Beach barrier“

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Hesp, Patrick A., Sergio R. Dillenburg, Eduardo G. Barboza, Luiz J. Tomazelli, Ricardo N. Ayup-Zouain, Luciana S. Esteves, Nelson L. S. Gruber, Elirio E. Toldo-Jr., Luiz L. C. de A. Tabajara und Luiz C. P. Clerot. „Beach ridges, foredunes or transgressive dunefields? Definitions and an examination of the Torres to Tramandaí barrier system, Southern Brazil“. Anais da Academia Brasileira de Ciências 77, Nr. 3 (September 2005): 493–508. http://dx.doi.org/10.1590/s0001-37652005000300010.

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Many prograded barriers and some dunefields in theworld have been termed 'beach ridge' plains, but the actual genesis of the 'ridges' is often unknown. Use of the terms, berms, beach ridges and foredunes is also confusing in the literature because their definitions are highly variable and are commonly used interchangeably. Thus, the formation and definition of sand berms, beach ridges and foredunes is briefly reviewed. Beach ridges are re-defined as entirely wave formed deposits which are most commonly formed during high wave conditions and/or elevated water levels (e.g. storm surges). Foredunes are formed by aeolian sand deposition in vegetation on the backshore. Some dunefields in Brazil have been called beach ridge plains when they are, in fact, foredune plains, transgressive dunefields, or complex barriers (i.e. barriers comprising two types of dunes). The Holocene barrier extending from Torres to Tramandaí in southern Brazil has been regarded as a beach ridge plain. The landforms of this Holocene barrier comprise wide, relatively linear, widely spaced (400-600m), shore parallel ridges on the landward half, and more closely spaced (80-400m), lobate and crescentic, discrete ridges on the seaward half. Low, rolling dunefields, sand sheets, nebkha fields and deflation plains occur between the ridges. The barrier is re-interpreted as a prograded, transgressive dunefield barrier.

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Ions, Kristian, Harshinie Karunarathna, Dominic E. Reeve und Douglas Pender. „Gravel Barrier Beach Morphodynamic Response to Extreme Conditions“. Journal of Marine Science and Engineering 9, Nr. 2 (28.01.2021): 135. http://dx.doi.org/10.3390/jmse9020135.

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Gravel beaches and barriers form a valuable natural protection for many shorelines. The paper presents a numerical modelling study of gravel barrier beach response to storm wave conditions. The XBeach non-hydrostatic model was set up in 1D mode to investigate barrier volume change and overwash under a wide range of unimodal and bimodal storm conditions and barrier cross sections. The numerical model was validated against conditions at Hurst Castle Spit, UK. The validated model is used to simulate the response of a range of gravel barrier cross sections under a wide selection of statistically significant storm wave and water level scenarios thus simulating an ensemble of barrier volume change and overwash. This ensemble of results was used to develop a simple parametric model for estimating barrier volume change during a given storm and water level condition under unimodal storm conditions. Numerical simulations of barrier response to bimodal storm conditions, which are a common occurrence in many parts of the UK were also investigated. It was found that barrier volume change and overwash from bimodal storms will be higher than that from unimodal storms if the swell percentage in the bimodal spectrum is greater than 40%. The model is demonstrated as providing a useful tool for estimating barrier volume change, a commonly used measure used in gravel barrier beach management.

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Whitford, D. J., und E. B. Thornton. „LONGSHORE CURRENT FORCING AT A BARRED BEACH“. Coastal Engineering Proceedings 1, Nr. 21 (29.01.1988): 5. http://dx.doi.org/10.9753/icce.v21.5.

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The FRF site is located along a 100-km unbroken stretch of barrier island formation known as North Carolina's "Outer Banks." There are no littoral barriers to perturbate incoming wave trains along the entire reach of shoreline. The site has a tidal range of 0.5 to 2.0 m and regular offshore bathymetry.

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Nicholls, Robert J., Lauren Burt, Joel Smethurst und Charlotte Thompson. „IMPLICATIONS OF CONSOLIDATION ON BARRIER BEACH STABILITY“. Coastal Engineering Proceedings, Nr. 36 (30.12.2018): 67. http://dx.doi.org/10.9753/icce.v36.sediment.67.

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Barrier beaches often overlie backbarrier deposits composed of poorly consolidated sediments. Hence, they can consolidate significantly if loaded. A retreating barrier beach provides such a load. In the static situation of beach nourishment, the increased load of the raised beach volume will also cause increased consolidation. These can lower beach elevation promoting wave overtopping, overwashing and retreat. However, there is limited research concerning the role of consolidation on the stability of barrier beaches worldwide. This paper focuses on this issue using Hurst Spit on the UK south coast as a study site where consolidation is a known significant process (Nicholls, 1985; Burt et al., 2018). It is a storm beach composed of shingle (pebble and cobble) sediments and formerly retreated at 2 to 3 m/yr, Since the later 1990s it has been more stabilized by a major nourishment (Bradbury and Kidd, 1998), but continues to retreat slowly (Figure 1). A second nourishment phase is now being actively assessed following major damage in the large storm of 14 February 2014. In this context, the role of consolidation has been analyzed via new data collection, consolidation modelling and morphodynamic modelling. This paper presents these results and their implications.

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Clark, James S. „Dynamism in the Barrier‐Beach Vegetation of Great South Beach, New York“. Ecological Monographs 56, Nr. 2 (Juni 1986): 97–126. http://dx.doi.org/10.2307/1942504.

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McGovern, Theresa, und Paul Ross. „BARRIER BEACH COMMUNITY OPTS FOR VACUUM SEWERS“. Proceedings of the Water Environment Federation 2002, Nr. 14 (01.01.2002): 389–407. http://dx.doi.org/10.2175/193864702784247981.

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Hamilton, Thomas R. „A Transect Study of a Barrier Beach“. American Biology Teacher 50, Nr. 2 (01.02.1988): 107–9. http://dx.doi.org/10.2307/4448656.

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Dubois, Roger N. „Barrier-beach erosion and rising sea level“. Geology 18, Nr. 11 (1990): 1150. http://dx.doi.org/10.1130/0091-7613(1990)018<1150:bbears>2.3.co;2.

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Borah, Deva K., und Armando Balloffet. „Beach Evolution Caused by Littoral Drift Barrier“. Journal of Waterway, Port, Coastal, and Ocean Engineering 111, Nr. 4 (Januar 1985): 645–60. http://dx.doi.org/10.1061/(asce)0733-950x(1985)111:4(645).

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Feng, Jing, und Wei Wang. „The Use of Heavy Minerals in the Investigation of Barrier-Lagoon Coasts Development in Dapeng Peninsula, China“. Minerals 9, Nr. 6 (05.06.2019): 347. http://dx.doi.org/10.3390/min9060347.

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Typical barrier-lagoon systems are developed at Dongchong and Xichong on the southern coast of the Dapeng Peninsula of Guangdong, China. This paper studies the evolution of the barrier coasts of the peninsula, using the examples of the Dongchong and Xichong Bays. The Holocene stratigraphic records from borehole drilling on the coast of Dongchong and Xichong show that lagoon sediments are overlaid with beach deposits, indicating that the barriers migrated landward and climbed over the lagoon sediments when the shoreface retreated during the Holocene transgression, reaching the present positions after 7–8 ka BP. Heavy mineral analysis in this paper shows that: (1) the ancient beach sediments of the two bays have the same heavy mineral assemblages, which are different from those of modern beaches; (2) the present beaches of the two bays have different heavy mineral assemblages, even they are located less than 3000 m from each other on the same coast. This supports the hypothesis that the barriers originally came from the inner shelves during the Holocene transgression, but draws a new conclusion that the source of the beach sediments changed to inland rivers over the last thousand years because of a lack of sediment source from the sea floor.

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Ciarletta, Daniel J., Jennifer L. Miselis, Justin L. Shawler und Christopher J. Hein. „Quantifying thresholds of barrier geomorphic change in a cross-shore sediment-partitioning model“. Earth Surface Dynamics 9, Nr. 2 (17.03.2021): 183–203. http://dx.doi.org/10.5194/esurf-9-183-2021.

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Abstract. Barrier coasts, including barrier islands, beach-ridge plains, and associated landforms, can assume a broad spectrum of morphologies over multi-decadal scales that reflect conditions of sediment availability, accommodation, and relative sea-level rise. However, the quantitative thresholds of these controls on barrier-system behavior remain largely unexplored, even as modern sea-level rise and anthropogenic modification of sediment availability increasingly reshape the world's sandy coastlines. In this study, we conceptualize barrier coasts as sediment-partitioning frameworks, distributing sand delivered from the shoreface to the subaqueous and subaerial components of the coastal system. Using an idealized morphodynamic model, we explore thresholds of behavioral and morphologic change over decadal to centennial timescales, simulating barrier evolution within quasi-stratigraphic morphological cross sections. Our results indicate a wide diversity of barrier behaviors can be explained by the balance of fluxes delivered to the beach vs. the dune or backbarrier, including previously understudied forms of transgression that allow the subaerial system to continue accumulating sediment during landward migration. Most importantly, our results show that barrier state transitions between progradation, cross-shore amalgamation, aggradation, and transgression are controlled largely through balances within a narrow range of relative sea-level rise and sediment flux. This suggests that, in the face of rising sea levels, subtle changes in sediment fluxes could result in significant changes in barrier morphology. We also demonstrate that modeled barriers with reduced vertical sediment accommodation are highly sensitive to the magnitude and direction of shoreface fluxes. Therefore, natural barriers with limited sediment accommodation could allow for exploration of the future effects of sea-level rise and changing flux magnitudes over a period of years as opposed to the decades required for similar responses in sediment-rich barrier systems. Finally, because our model creates stratigraphy generated under different input parameters, we propose that it could be used in combination with stratigraphic data to hindcast the sensitivity of existing barriers and infer changes in prehistoric morphology, which we anticipate will provide a baseline to assess the reliability of forward modeling predictions.

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Perera, Eranda, Fangfang Zhu, Nicholas Dodd, Riccardo Briganti und Chris Blenkinsopp. „SURFACE-GROUNDWATER FLOW NUMERICAL MODEL FOR COASTAL BARRIER BEACH“. Coastal Engineering Proceedings, Nr. 36 (30.12.2018): 92. http://dx.doi.org/10.9753/icce.v36.risk.92.

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Fine-grain beaches are relatively common where the beach forms part of a larger coastal barrier system. In such a coastal system, different water levels could be present in the seaward side and back-barrier lagoon. The water level changes in the steady-state lagoon may potentially induce groundwater dynamics near the beach which would subsequently affect seepage flow into (or out of) the beach. The exchange of water could generate varying hydrodynamical and morphodynamical behaviour at the seaward boundary. Hence, it is important to gain insight into groundwater flow dynamics which results in exchange of water between sea, barrier and lagoon; especially for coastal engineers responsible for planning and managing such a coastal environment. In present work, a numerical model is developed to simulate flows through a coastal barrier and it is validated against prototype-scale experimental results, which can then be extended to model small time-scale groundwater flows that may be too expensive or impractical to set up in a lab.

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Rinaldo, Tobia, Kiran Adhithya Ramakrishnan, Ignacio Rodriguez-Iturbe und Orencio Durán Vinent. „Probabilistic structure of events controlling the after-storm recovery of coastal dunes“. Proceedings of the National Academy of Sciences 118, Nr. 1 (21.12.2020): e2013254118. http://dx.doi.org/10.1073/pnas.2013254118.

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Coastal dunes protect beach communities and ecosystems from rising seas and storm flooding and influence the stability of barrier islands by preventing overwashes and limiting barrier migration. Therefore, the degree of dune recovery after a large storm provides a simple measure of the short-term resiliency (and potential long-term vulnerability) of barrier islands to external stresses. Dune recovery is modulated by low-intensity/high-frequency high-water events (HWEs), which remain poorly understood compared to the low-frequency extreme events eroding mature dunes and dominating the short-term socio-economic impacts on coastal communities. Here, we define HWEs and analyze their probabilistic structure using time series of still-water level and deep-water wave data from multiple locations around the world. We find that HWEs overtopping the beach can be modeled as a marked Poisson process with exponentially distributed sizes or marks and have a mean size that varies surprisingly little with location. This homogeneity of global HWEs is related to the distribution of the extreme values of a wave-runup parameter,HR=HsL0, defined in terms of deep-water significant wave heightHsand peak wavelengthL0. Furthermore, the characteristic beach elevation at any given location seems to be tied to a constant HWE frequency of about one event per month, which suggests a stochastic dynamics behind beach stabilization. Our results open the door to the development of stochastic models of beach, dune, and barrier dynamics, as well as a better understanding of wave-driven nuisance flooding.

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Ruiz de Alegria-Arzaburu, Amaia, Jon J. Williams und Gerhard Masselink. „APPLICATION OF XBEACH TO MODEL STORM RESPONSE ON A MACROTIDAL GRAVEL BARRIER“. Coastal Engineering Proceedings 1, Nr. 32 (23.01.2011): 39. http://dx.doi.org/10.9753/icce.v32.sediment.39.

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The process-based XBeach numerical model has been used to simulate storm-induced morphological response on a macrotidal gravel barrier located in southwest UK. Using well-established parameterisation to define all relevant hydrodynamic, groundwater and sediment processes, the model was applied in 1D mode to simulate observed storm-induced beach profile responses. Investigations showed that the morphological response of the beach was best modelled using a total drag coefficient, CD, of 0.007, and a hydraulic conductivity, K, of 0.05ms-1. Results obtained from simulations with and without beach groundwater highlighted the need to account for groundwater effects when modelling morphological changes on gravel beaches. The model has been found unable of reproducing the formation of a berm, thus, beach recovery conditions cannot be modelled. This is mainly attributed to the fact that XBeach models long waves rather than individual waves, and thus it cannot simulate individual swash events that contribute to onshore sediment transport and berm accretion. However, the model is shown to provide good estimates of post-storm gravel beach/barrier profiles, and to define the threshold for overwash occurrence. Both attributes have utility in a range of practical coastal engineering and management applications.

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Leatherman, Stephen P. „Barrier Migration of Nauset Beach, Cape Cod, Massachusetts“. Journal of Coastal Research 101, sp1 (26.08.2020): 89. http://dx.doi.org/10.2112/jcr-si101-019.1.

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Anonymous. „Beach groin acts as barrier to longshore transport“. Eos, Transactions American Geophysical Union 71, Nr. 38 (1990): 1090. http://dx.doi.org/10.1029/eo071i038p01090-01.

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Silvestre, Carolina Pereira, André Luiz Carvalho da Silva, Maria Augusta Martins da Silva und Amilsom Rangel Rodrigues. „INVESTIGATION OF THE INTERNAL STRUCTURE AND EVOLUTION OF THE HOLOCENE BARRIER OF MARICÁ (RIO DE JANEIRO, BRAZIL)“. Revista Brasileira de Geofísica 33, Nr. 3 (22.07.2015): 461. http://dx.doi.org/10.22564/rbgf.v33i3.948.

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ABSTRACT. The objective of this study is the identification of the internal structure of the Holocene barrier of the Maricá coastal plain (Rio de Janeiro, Brazil) for the understanding of the evolution of this coast. The regional geomorphology is characterized by the large Maricá lagoon and by two sandy barriers which confines a series of small near-dry lagoons. Geophysical data obtained from ground-penetrating radar (GPR) images, with 400 and 200 MHz shielded antennae and borehole samples, both reaching down to about 10 meters in depth, provided information about the sedimentary architecture and geological and oceanographical processes responsible for the evolution of this area in the Holocene. The results show that the barrier internal structure is formed by a set of strata presenting different geometries, dip directions and organization, relative to the following depositional environments: dunes, washover fans, beach and tidal channels. It was possible to determine the importance of the sea level changes, longshore currents and overwash processes for the barrier development. Strong reflectors representing eolian strata dipping towards the continent point out to a phase of barrier retrogradation; afterwards, a succession of very well preserved beach paleoscarps, located south of the previous barrier, shows a phase of barrier progradation. Such evidences indicate that the barrier evolved according to the Holocene sea level fluctuations recognized for the Brazilian coast.Keywords: ground-penetrating radar, barrier-lagoon system, Holocene, Maricá coast. RESUMO. O presente estudo objetivou identificar a estrutura interna da barreira holocênica buscando compreender a evolução da planície costeira de Maricá (Rio de Janeiro). A geomorfologia regional é caracterizada pela Lagoa de Maricá e duas barreiras arenosas, separadas por pequenas lagunas colmatadas. Dados geofísicos obtidos com um georadar, com antenas de 400 e 200 MHz, e amostras de sondagem geológica, ambos até a profundidade média de 10 metros, forneceram informações sobre a arquitetura sedimentar e os processos geológicos e oceanográficos responsáveis pela evolução desta área no Holoceno. Os resultados mostram que a estrutura interna da barreira é formada por um conjunto de estratos de diferentes geometrias, direções de mergulho e modos de organização relacionados aos seguintes ambientes deposicionais: dunas, leques de arrombamento, praias e canais de maré. Essas características permitiram o entendimento da dinâmica costeira responsável pelo desenvolvimento da barreira, com destaque para as variações do nível do mar, correntes de deriva litorânea e mecanismos de sobrelavagem. Refletores marcantes representando estratos eólicos inclinados para o continente indicam uma fase de retrogradação da barreira; a esse episódio se seguiu um período marcado por sucessivas paleoescarpas de tempestade, localizadas mais ao sul, indicando uma fase de progradação. Essas evidências mostram que a barreira evoluiu de acordo com as fases de transgressão e regressão marinha do Holoceno reconhecidas para o litoral brasileiro.Palavras-chave: georadar, sistema barreira-laguna, Holoceno, litoral de Maricá.

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Eden, Jr., Edwin W. „EFFECT OF LAKE WORTH AND SOUTH LAKE WORTH INLETS ON THE MOVEMENT OF LITTORAL MATERIAL“. Coastal Engineering Proceedings 1, Nr. 6 (29.01.2011): 24. http://dx.doi.org/10.9753/icce.v6.24.

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Lake Worth and South Lake Worth Inlets are artificial inlets connecting Lake Worth with the Atlantic Ocean. They are located on the east coast of Florida about 70 miles north of Miami and 300 miles south of Jacksonville. Lake Worth is a salt-water sound extending in a north-south direction, generally parallel to the ocean shore, as shown on figure 1. It is separated from the ocean by a barrier beach, 250 feet to about 3,600 feet wide and up to about 25 feet in elevation. The barrier beach is composed principally of sand, a portion of which is artificial fill over former low-lying marshy areas. There are occasional outcroppings of coquina rock on the barrier beach and in the offshore area. In this locality the offshore bottom is rather steep; the 100-fathom depth, lying closer to the shore than along other parts of the Atlantic coast, is about 5-1/2 miles offshore at Lake Worth Inlet.

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Xuan Tinh, Nguyen, Magnus Larson, Chantal Donnelly und Hitoshi Tanaka. „LABORATORY EXPERIMENT ON CROSS-SHORE BARRIER SPIT EVOLUTION BY STORM DYNAMICS“. Coastal Engineering Proceedings 1, Nr. 32 (19.01.2011): 32. http://dx.doi.org/10.9753/icce.v32.sediment.32.

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Every year there are many severe storms occurring around the world, in general, and in Japan, in particular. The occurrence of storms is expected to increase because of the global warming effects. An increasing wave height together with a rising mean water level during a storm create a high possibility for waves to overtop the beach crest causing a lot of sediment to be eroded to offshore areas or deposited in the inland direction. The study of the barrier island response to storms has therefore become very important in terms of sediment transport and beach morphology change, as well as damage to nearshore structures due to runup overwash and inundation overwash. However, changes in the beach profile and prevailing sediment transport mechanisms during a real event are difficult to obtain. Thus, laboratory studies are necessary to conduct. This study presents a laboratory experiment on the impact of storms on a sandy barrier islands. The main aim is to investigate the entire barrier island (or sand spit) response due to storm conditions considering the increase in water level due to storm surge. Also, further development of an analytical model for barrier profile change caused by runup overwash is presented and obtained results overall captured order-of-magnitude barrier face retreat and volume changes after the storm.

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Isdarmanto, Isdarmanto, und Oentoeng Soebyanto. „ANALISIS POTENSI PANTAI GLAGAH SEBAGAI EKOWISATA UNGGULAN DI KABUPATEN KULONPROGO“. Kepariwisataan: Jurnal Ilmiah 12, Nr. 02 (31.05.2018): 1–12. http://dx.doi.org/10.47256/kepariwisataan.v12i02.82.

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Glagah Beach is one of the most potential beaches and has the uniqueness as the charm and excellence of other southern seas. Glagah Beach located in Kulon Progo Regency is the only beach in Java that has a breakwater and has a lagoon on the edge of the sea separated by the sea so that large waves do not reach the lagoon. According to the typology of Glagah beach it self can be included in the classification of marine deposition coast. This is because the beach is formed due to the deposition deposition of river sedimentation material to the sea. This condition can be indicated by the emergence of a barrier coast emerging due to sedimentation from the river that empties into the location, then subject to marine effects that result in the formation of the lagoon. The process of sedimentation that occurs due to the flow and sedimentation of the river mouth that causes sedimentation in the coastal area. Qualitative research methods used with data collection techniques in the form of observation, interviews, documents, and various sources of data so it can be more clearly known geographical aspects of Glagah Beach, tourism profile, tourist visit conditions, tourism potential Glagah Beach, and to know the constraints which faced Glagah Beach tourism object and how the development strategy of Glagah Beach tourist attraction area in the future. Glagah Beach is a natural attraction that has the privilege and excellence compared to other beaches in Yogyakarta that need to keep the sustainability and need to be managed more effectively by the community and the local government as a policy holder so Glagah Beach became one of the leading ecotourism object which is interesting in Kulon Progo Regency Yogyakarta. Keywords: Glagah Beach; Sea Lagoon; Barrier Coast

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Frey, R. W., und J. D. Howard. „Beaches and beach-related facies, Holocene barrier islands of Georgia“. Geological Magazine 125, Nr. 6 (November 1988): 621–40. http://dx.doi.org/10.1017/s0016756800023438.

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AbstractThe mesotidal coast of Georgia encompasses diverse sedimentary features and depositional environments, most of which typify major facies of the entire Georgia Bight – a broad embayment on the southeastern U.S. shelf. Barrier island strandline environments especially include tidal inlets and shoals, the beach shoreface, foreshore, and backshore, and dunes and washover fans. Low energy beach segments may grade directly into small seaside tidal flats. Relict salt marsh deposits crop out on erosional beaches. All deposits are in dynamic equilibrium with fluctuating coastal conditions and a gradual rise in sea level.Most of these facies are important in interpreting ancient epeiric transgressive/regressive coastal sequences. Pronounced local variations in the overall sequence result from complex latero-vertical relationships between (1) the shoreface, foreshore, and shoals, and (2) the shoals, low energy beaches, and beach-related tidal flats. Washover fans and relict deposits on erosional beaches cause perturbations within present day lateral relationships but are normal in transgressive facies tracts along such coasts. Close stratigraphic control of outcrops or cores would be necessary for detailed reconstructions of, or correlations among, ancient analogs.

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Simeone, Simone, Luca Palombo, Emanuela Molinaroli, Walter Brambilla, Alessandro Conforti und Giovanni De Falco. „Shoreline Response to Wave Forcing and Sea Level Rise along a Geomorphological Complex Coastline (Western Sardinia, Mediterranean Sea)“. Applied Sciences 11, Nr. 9 (28.04.2021): 4009. http://dx.doi.org/10.3390/app11094009.

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Beaches responses to storms, as well as their potential adaptation to the foreseeable sea level rise (SLR), were investigated along three beaches in a coastal tract in western Sardinia (Western Mediterranean Sea). The grain size of the sediments, the beach profile variability and the wave climate were analyzed in order to relate morphological changes, geological inheritances and waves forcing. Multibeam, single-beam and lidar data were used to characterize the inner shelf morphologies and to reproduce the flooding due to the SLR. The studied beaches experienced major changes when consecutive storms, rather than singles ones, occurred along the coastline. The sediment availability, the grain size and the geomorphological structure of the beaches were the most important factors influencing the beach response. On the sediment-deprived coarse beaches the headlands favor the beach rotation, and the gravel barrier morphology can increase the resistance against storms. On the sediment-abundant beaches, the cross-shore sediment transport towards a submerged area leads to a lowering in the subaerial beach level and a contemporaneous shoreline retreat in response to storms. A very limited ingression of the sea is related to the SLR. This process may affect (i) the gravel barrier, promoting a roll over due to the increase in overwash; (ii) the embayed beach increasing its degree of embayment as headlands become more prominent, and (iii) the sediment-abundant beach with an erosion of the whole subaerial beach during storms, which can also involve the foredune area.

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Feyssat, Pierre, Raphaël Certain, Nicolas Robin, Olivier Raynal, Nicolas Aleman, Bertil Hebert, Antoine Lamy und Jean-Paul Barusseau. „Morphodynamic Behaviour of a Mediterranean Intermittent Estuary with Opening Phases Primarily Dominated by Offshore Winds“. Journal of Marine Science and Engineering 10, Nr. 12 (25.11.2022): 1817. http://dx.doi.org/10.3390/jmse10121817.

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This study focuses on the dynamics of an intermittent estuary in a wave-dominated (microtidal) area, with low fluvial discharges and strong dominant offshore wind regimes. The aims are to understand the effect of these particular environmental factors in the dynamics of such estuaries. The results allow us to propose a synthetic morphodynamic model of evolution whereby opening phases are predominantly controlled by offshore winds, which have a significant influence in the northern Mediterranean. Inputs from rainfall/karst discharge and the overtopping of storm waves cause the lagoon to fill. Closing phases are controlled by the slight easterly swell which forms a berm at the inlet entrance. On occasion, major storms can also contribute to barrier opening. Nevertheless, offshore wind remains the main controlling factor allowing the surge of lagoon waters behind the beach barrier and the lowering of the berm by wind deflation. This leads to opening of the barrier due to the overflow of lagoon waters at the beach megacusp horns, thus connecting the sub-aerial beach with the inner bar system that is developed on topographically low sectors of the barrier. To the best of the authors’ knowledge, this type of estuary is not described in the literature.

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Yang, Byungyun, Marguerite Madden, Jinwon Kim und Thomas R. Jordan. „Geospatial analysis of barrier island beach availability to tourists“. Tourism Management 33, Nr. 4 (August 2012): 840–54. http://dx.doi.org/10.1016/j.tourman.2011.08.013.

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Bosma, Jorn, Timothy Price und Gerben Ruessink. „MIXED-SEDIMENT DYNAMICS AT A BACK-BARRIER BEACH NOURISHMENT“. Coastal Engineering Proceedings, Nr. 37 (01.09.2023): 53. http://dx.doi.org/10.9753/icce.v37.sediment.53.

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Sand nourishments are increasingly applied to systems where the morphodynamics are driven by mixed hydrodynamic forcing (i.e., tides and waves) rather than by waves alone. Here, mixed-sand deposits are usually retrofitted to inadequate, hard flood defenses to act as a buffer against erosion and eventually failure of such infrastructure. Introducing different grain sizes into a system leads to more complex, differentiated sediment transport, as coarser fractions are mobilized under different conditions than finer fractions (McCarron et al., 2019). By focusing on a nourishment on the leeward side of a barrier island, we aim to find quantitative answers to the questions where, when and how the mixed-sediment composition changes and how that already is and will be expressed in the morphologic evolution of the area.

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Housego, Rachel, Britt Raubenheimer, Steve Elgar, Levi Gorrell, Heidi Wadman, Jesse McNinch und Kate Brodie. „BARRIER ISLAND GROUNDWATER“. Coastal Engineering Proceedings, Nr. 36 (30.12.2018): 10. http://dx.doi.org/10.9753/icce.v36.risk.10.

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Storms can have long-term impacts on the groundwater flows and subsurface salinity structure in coastal aquifers. Previous studies have shown that tides, wave driven infiltration, and storm surge elevate the groundwater level within the beach (Nielsen 1999, Cartwright 2004). The resulting bulge of high groundwater propagates inland, and may cause flooding up to several days after a storm has passed (Gallien 2016). In addition, waves, tides, and storm surge force saltwater to infiltrate into the aquifer above the fresher terrestrial groundwater, and storm-driven pulses of salinity may persist for months (Robinson et al. 2014). Here, observations of groundwater heads and salinities collected continuously for three years are used to examine the effects of ocean storms, wind-driven fluctuations in sound water levels, and morphological changes on a barrier island aquifer.

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Borówka II, Mieczysław, und Karol Rotnicki. „Budget of the eolian sand transport on the sandy barrier beach (a case study of the Łeba Barrier, southern Baltic coast, Poland)“. Zeitschrift für Geomorphologie 45, Nr. 1 (23.03.2001): 55–79. http://dx.doi.org/10.1127/zfg/45/2001/55.

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Costas, Susana. „Evolutionary Trajectories of Coastal Sand Barriers along the West Portuguese Coast during the Holocene“. Journal of Marine Science and Engineering 10, Nr. 12 (05.12.2022): 1894. http://dx.doi.org/10.3390/jmse10121894.

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Coastal sand barriers are dynamic features with complex depositional sequences holding critical information regarding system response to disturbances at secular to millennial time scales. Here, the evolutionary trajectories of three barriers located along the Portuguese coast are reconstructed over the Middle to Late Holocene using geophysical subsurface images, modern morphology and dating of dune and beach deposits. The integration of new and available information from the documents of the selected site contrasts histories with modern barriers displaying ages ranging from hundreds to thousands of years and non-linear trajectories defined by shifts between morphological states. Younger barriers appear to represent the latest progradational state within a history of landward barrier migration, where progradational states alternated with transgressive states. Conversely, the oldest barrier shows a single phase of barrier growth, despite some minor hiatus in progradation. Barrier state shifts appear to have simultaneously occurred across systems, suggesting external drivers of regional scale linked to Holocene climate variability, namely, periods of storminess activity, while the different trajectories displayed by the three sites appear related to site-specific variables controlling exposure to waves and winds. Exposed sites showed a lower ability to absorb disturbances and a greater range of system responses, varying between transgressive and progradational states.

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Kriesel, Warren, Craig E. Landry und Andrew Keeler. „Coastal Erosion Management from a Community Economics Perspective: The Feasibility and Efficiency of User Fees“. Journal of Agricultural and Applied Economics 37, Nr. 2 (August 2005): 451–61. http://dx.doi.org/10.1017/s1074070800006921.

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Coastal communities cannot depend on funding from the state or federal government to maintain high-quality beaches that benefit the public and attract tourist revenues. This article investigates the feasibility and efficiency of beach improvement projects at two Georgia barrier islands through the alternative funding mechanisms of general-revenue financing and user fees. Benefits are calculated from an intensive, on-site survey of beach visitors, and the costs are calculated from observable sources. The analyses presented support beach improvement as an effective policy on both islands under all scenarios considered.

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Bennett, Matthew R., Nigel J. Cassidy und Jeremy Pile. „Internal structure of a barrier beach as revealed by ground penetrating radar (GPR): Chesil beach, UK“. Geomorphology 104, Nr. 3-4 (März 2009): 218–29. http://dx.doi.org/10.1016/j.geomorph.2008.08.015.

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Mallavarapu, Sravani, Nobuhisa Kobayashi und Tingting Zhu. „EFFECT OF NET CROSS-SHORE SAND TRANSPORT ON BEACH PROFILES“. Coastal Engineering Proceedings, Nr. 36 (30.12.2018): 56. http://dx.doi.org/10.9753/icce.v36.sediment.56.

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The concept of an equilibrium beach profile is convenient and widely adopted for long-term simulations of shoreline changes and beach profile evolutions. The equilibrium profile is regarded as a profile with net cross-shore sediment transport rate qn = 0. Kobayashi et al. (2008) proposed formulas for offshore suspended sediment transport rate qs and onshore bedload transport rate qb and derived the equilibrium profile equation of Dean (1991) for the case of qn = (qs+ qb) = 0. Their model is extended to equilibrium profiles with net offshore (qn0) sediment transport rates. The equilibrium profile with qn=0 is modified by periodic beach nourishment (qn0). The extended model predicts the degree and location of profile modifications as a function of qn and it can be used to improve beach nourishment design and devise barrier beach overwash countermeasures.

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Tuchkovenko, Yu S., und D. V. Kushnir. „Modeling of variability of hydrological characteristics of the Tuzla group of lagoons under various variants of their water exchange with the sea“. Ukrainian hydrometeorological journal, Nr. 29 (21.07.2022): 68–84. http://dx.doi.org/10.31481/uhmj.29.2022.06.

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The article is devoted to solving the problem of stabilization of hydrological regime and hydro-ecological conditions of the Tuzla group of lagoons located in the central part of the Danube-Dniester interfluve by ensuring and regulating their water exchange with the open sea through artificially created channels in the barrier beach that separates the water body from the sea. The research presents the results of adaptation of the well-known modern numerical hydrodynamic model Delft3D Flow Flexible Mesh to the conditions of the Tuzla group of lagoons, as well as the results of its application to determine the effectiveness of various variants for ensuring water exchange with the sea based on the outcomes of scenario mathematical modeling. In particular, the following variants of channels functioning were studied: (1) a relatively narrow connecting channel at the 2nd km of the barrier beach (near the Burnas Lagoon) together with a wide and deep outlet that existed before 2015 at the 24th km of the barrier beach (near the Shagany Lagoon); (2) a wide controllable connecting channel in the Shagany Lagoon placed on the outlet, alongside with the above-mentioned channel in the Burnas Lagoon; (3) an additional (third) narrow channel at the strip of the barrier beach near the Alibey Lagoon. The characteristics of the annual cycle of water salinity spatio-temporal variability were used as indicators of the effectiveness of management decisions for ensuring the stability of the lagoons' hydro-ecological conditions. Based on the analysis of the scenario modeling results it was concluded that the optimum solution of the problem related to stabilizing the hydro-ecological regime of the water body consists in ensuring the constant multidirectional water exchange with the sea through two artificial connecting channels in the barrier beach (both with bottom marks of minus 1.0 m (Baltic Height System) and 60 m and 15 m wide for the Shagany Lagoon and the Burnas Lagoon respectively) throughout the year. This will deny any salinization of the water body over the long term. For the specified variant the time of complete water renewal with sea water for the main lagoons of the Tuzla group would constitute 8 and 12 months for the Shagany Lagoon and the Alibey/Burnas Lagoons respectively.

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Long, Joseph W., Matthew B. Vincent und Andrea D. Hawkes. „OBSERVATIONS AND MODELING OF EROSION AND RECOVERY OF A COUPLED BEACH-DUNE SYSTEM“. Coastal Engineering Proceedings, Nr. 37 (01.09.2023): 71. http://dx.doi.org/10.9753/icce.v37.sediment.71.

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The geomorphic and ecological vulnerability of barrier islands is influenced by the way they respond to oceanographic and anthropogenic forcing over a broad range of temporal scales. Integrated models capable of simulating these processes are increasingly necessary to understand barrier island trajectories under future conditions and to aid in management decisions by evaluating the impact of potential restoration activities. While there are numerical models capable of simulating some of the dominant barrier processes, the role of beach berm evolution is rarely included despite the important function of berms in sustaining beaches, enabling dune growth via Aeolian transport, and mitigating backshore and dune erosion during storm events. This is primarily due to a lack of available data that resolves details of beach profile evolution at necessary temporal scales (e.g., seasonal, post-storm recovery, etc.) to test and develop models and the inherent difficulty of including these intra-annual processes into decadal scale models of barrier island evolution. Here we describe a unique and growing dataset of environmental forcing and barrier island topographic change. We also use the dataset to develop and test a model for barrier island evolution and quantify the role of storms, moderate wave conditions, and wind-driven transport in dictating coastal change on various timescales.

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Chadwick, A. J., H. Karunarathna, W. R. Gehrels, A. C. Massey, D. O'Brien und D. Dales. „A new analysis of the Slapton barrier beach system, UK“. Proceedings of the Institution of Civil Engineers - Maritime Engineering 158, Nr. 4 (Dezember 2005): 147–61. http://dx.doi.org/10.1680/maen.2005.158.4.147.

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Clark, J. S., J. T. Overpeck, T. Webb und W. A. Patterson. „Pollen stratigraphic correlation and dating of barrier-beach peat sections“. Review of Palaeobotany and Palynology 47, Nr. 1-2 (Februar 1986): 145–68. http://dx.doi.org/10.1016/0034-6667(86)90011-4.

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Wernette, Phillipe A., Chris Houser, Bradley A. Weymer, Mark E. Everett, Michael P. Bishop und Bobby Reece. „Directional dependency and coastal framework geology: implications for barrier island resilience“. Earth Surface Dynamics 6, Nr. 4 (27.11.2018): 1139–53. http://dx.doi.org/10.5194/esurf-6-1139-2018.

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Abstract. Barrier island transgression is influenced by the alongshore variation in beach and dune morphology, which determines the amount of sediment moved landward through wash-over. While several studies have demonstrated how variations in dune morphology affect island response to storms, the reasons for that variation and the implications for island management remain unclear. This paper builds on previous research by demonstrating that paleo-channels in the irregular framework geology can have a directional influence on alongshore beach and dune morphology. The influence of relict paleo-channels on beach and dune morphology on Padre Island National Seashore, Texas, was quantified by isolating the long-range dependence (LRD) parameter in autoregressive fractionally integrated moving average (ARFIMA) models, originally developed for stock market economic forecasting. ARFIMA models were fit across ∼250 unique spatial scales and a moving window approach was used to examine how LRD varied with computational scale and location along the island. The resulting LRD matrices were plotted by latitude to place the results in the context of previously identified variations in the framework geology. Results indicate that the LRD is not constant alongshore for all surface morphometrics. Many flares in the LRD plots correlate to relict infilled paleo-channels, indicating that the framework geology has a significant influence on the morphology of Padre Island National Seashore (PAIS). Barrier island surface morphology LRD is strongest at large paleo-channels and decreases to the north. The spatial patterns in LRD surface morphometrics and framework geology variations demonstrate that the influence of paleo-channels can be asymmetric (i.e., affecting beach–dune morphology preferentially in one direction alongshore) where the alongshore sediment transport gradient was unidirectional during island development. The asymmetric influence of framework geology on coastal morphology has long-term implications for coastal management activities because it dictates the long-term behavior of a barrier island. Coastal management projects should first seek to assess the framework geology and understand how it influences coastal processes in order to more effectively balance long-term natural variability with short-term societal pressure.

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Bluck, B. J. „Clast assembling, bed-forms and structure in gravel beaches“. Transactions of the Royal Society of Edinburgh: Earth Sciences 89, Nr. 4 (1998): 291–323. http://dx.doi.org/10.1017/s026359330000242x.

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AbstractBoth textural maturity and structure acquired by gravels on beaches are largely a response to the interaction between beach surface and wave-backwash energy. The turbulent energy driving the processes of particle rejection andselection at the surface of growing gravel sheets is partly controlled by the grain size of the sheet itself, so the process is to a large extent self-regulating. Beach surfaces are seen to comprise many discrete sheets of gravel competing for growth at their boundaries, but each characterised by a uniform or uniformly gradational texture.There are two main types of gravel sheet: (1) selection pavements which occur on low beach slopes, showing little areal grain-size or grain-shape variation, and (2) turbulence shadows which occur on steeper slopes and produce assemblages of clasts which may show perfect lateral shape and size gradation.The clasts which make up these various gravel sheets are termed ‘clast assemblages’, and such assemblages are the fundamental units from which beaches are constructed. Clast assemblages are classified in terms of their textural maturity—the degree to which they exhibit uniformity in clast size and shape. In beach sections they are, either singly or in combination, bounded by planes of discontinuity (bedding planes) to form beds.Repeated combinations of either clast assemblages or beds in a genetic association are regarded as sedimentary structures, many of which are diagnostic of the gravel beach environment. Growth of beaches involves the stacking of sedimentary structures, and four growth patterns have been identified. The beach structure is, therefore, classified in a hierarchy comprising clast assemblage, bed, structures and growth form, and it is the growth pattern which may be related to tidal range. P.ecognition of the processes which generate beach gravels through the structure of the gravels permits an analysis of the internal structure of major gravel bodies such as barrier beaches. It adds another set of criteria which may further lead to an understanding of the processes responsible for the generation and evolution of these large gravelforms.Three types of gravel lithosomes have been identified. (1) Regressive barrier bars which form a series of gravel ridges separated by lagoonal deposits. Barriers are built initially by swash bars which grow in size and coarsen through time to become wave-resistant forms. They form as a response to times when the sediment, unable to be evenly distributed and sorted on the beach surface, forms a discrete bar seaward of the active beach. This is the result of a punctuated or continuously high sediment supply compared with the wave energy available to disperse the sediment, or a falling sea level which shifts the locus of sediment accretion. (2) In contrast, regressive (prograding) gravel sheets form as a response to a continuous supply of sediment to the beach surface, allowing it to build seaward by the uniform accretion of sediment which is sorted and retained on its surface. (3) Gravel sheets produced in transgression are characterised by an abundance of spherical clasts and are often overlapped by the sand beaches which occur seaward of them.

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Cohen, Marcelo Cancela Lisboa, Adriana Vivan de Souza, Kam-Biu Liu, Erika Rodrigues, Qiang Yao, Luiz Carlos Ruiz Pessenda, Dilce Rossetti, Junghyung Ryu und Marianne Dietz. „Effects of Beach Nourishment Project on Coastal Geomorphology and Mangrove Dynamics in Southern Louisiana, USA“. Remote Sensing 13, Nr. 14 (08.07.2021): 2688. http://dx.doi.org/10.3390/rs13142688.

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Relative sea-level (RSL) rise associated with decreased fluvial sediment discharge and increased hurricane activity have contributed to the high rate of shoreline retreat and threatened coastal ecosystems in Port Fourchon, Louisiana, USA. This study, based on QuickBird/drone images (2004–2019) and LIDAR data (1998–2013), analyzed the impacts of shoreline dynamics on mangroves (Avicennia germinans) and marshes before and after the initiation of a beach nourishment project in 2013. The coastal barrier and dune crest migrated landward between 1998 and 2013. Meanwhile, the dune crest height increased between 1998 and 2001, then decreased in 2013, probably due to hurricane impacts. The total sediment volume along this sandy coastal barrier presented an overall trend of decline in the 1998–2013 period, resulting in a wetlands loss of ~15.6 ha along 4 km of coastline. This has led to a landward sand migration onto muddy tidal flats occupied by Avicennia germinans (1.08 ha) and Spartina (14.52 ha). However, the beach nourishment project resulted in the advancement of the beach barrier from Nov/2012 to Jan/2015, followed by a relatively stable period between Jan/2015 and Mar/2019. Additionally, both the dune crest height and sediment volume increased between 2013 and 2019. This set of factors favored the establishment and expansion of mangroves (3.2 ha) and saltmarshes (25.4 ha) along the backbarrier environments after 2013, allowing the tidal flats to keep pace with the RSL rise. However, waves and currents caused shoreline erosion following the beach nourishment project between Oct/2017 and Nov/2019, threatening wetlands by resuming the long-term process of shoreline retreat.

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GHIONIS, G., S. E. POULOS, E. VERYKIOU, A. KARDITSA, G. ALEXANDRAKIS und P. ANDRIS. „The Impact of an Extreme Storm Event on the Barrier Beach of the Lefkada Lagoon, NE Ionian Sea (Greece)“. Mediterranean Marine Science 16, Nr. 3 (14.09.2015): 562. http://dx.doi.org/10.12681/mms.948.

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The present investigation examines the characteristics of a high energy storm event, that took place on November 9-11, 2007 in the NE Ionian Sea (eastern Mediterranean), and its impact upon the barrier beach that separates the Lefkada lagoon from the open Ionian Sea. The storm event was caused by NW winds with speeds exceeding 20 m/s (40 knots), which have an annual frequency of occurrence less than 0.015%. This high energy event produced waves with >5 m significant offshore height and 9.5 s period; these waves developed on 10th November during the rapid rise of barometric pressure (~1.4 hPa/hr), which followed the barometric pressure drop from 1020.5 hPa at 06:00 (UTC) of 9th November to 1001.7 hPa at 06:00 h (UTC) of 10th November. Secondary breaking at the shoreline produced wave heights >1.5 m, associated with a surge of >0.4 m and a run-up capability of >2.4 m. The waves managed to overtop the barrier beach (elevations ~2.5 m), lowering the seaward side of the barrier beach by 10-30 cm and causing a coastline retreat of 0.9 to 2.2 m; these morphological changes correspond volumetrically to a sediment loss of approximately 8 m3/m of coastline length from the sub-aerial part of the beach. During the last three decades a significant change in the frequency of occurrence and direction (from S-SW-W to N-NW-NE) of severe storms with wind speeds exceeding 40 knots has been recorded, affecting the sediment transport pattern and contributing to the erosion of the north beaches of Lefkada.

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Abbasi, Iftikhar A. „Geological Assessment of the Khor Kharfot Sediments, Western Dhofar Region, Sultanate of Oman“. Sultan Qaboos University Journal for Science [SQUJS] 21, Nr. 1 (01.11.2016): 16. http://dx.doi.org/10.24200/squjs.vol21iss1pp16-25.

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Khor Kharfot is part of a coastal estuarine wetland system located in the western part of the Dhofar Governorate preserving a pristine ecosystem supporting a distinct vegetation and animal habitat. A sand barrier along the khor (local term for wetlands) mouth controls the mixing of fresh and marine water in the enclosed lagoon. In order to understand the geological controls on the khor formation, a geological map of the khor barrier and inlet area is prepared. The khor is bounded by Cretaceous and Tertiary carbonate rock sequences which are cut by a number of faults. The khor mouth and barrier are comprised of late Holocene deposits divided into seven units including i) beach sand, ii) beach sand mixed with wadi gravels, iii) scree and coastal dunes, iv) lagoon, v) soil and boulders, vi) wadi gravels, and vii) talus. The khor developed as an open estuary which changed to a barrier dominated lagoon due to falling fresh water supplies as a consequence of dwindling Khareef rains. The lagoon water is brackish due to the mixing of fresh and marine water and supports a distinct flora and fauna.

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Jafari, Navid H., Brian D. Harris und Timothy D. Stark. „LONG-TERM SUBSIDENCE OF BEACH NOURISHMENT AND DUNE RESTORATION IN CAMINADA HEADLANDS, COASTAL LOUISIANA“. Coastal Engineering Proceedings, Nr. 36 (30.12.2018): 66. http://dx.doi.org/10.9753/icce.v36.risk.66.

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Coastal barrier islands are the first line of defense for protecting wetlands, inland bays, and mainland regions from direct effects of wind, waves, and storms. Rosati (2006) indicate that 20 to 40% of the total sand volume can be sequestered and lost from the sandy barrier island through consolidation. As a result, predicting long-term subsurface sediment consolidation is integral to determining the ability of barrier islands to provide coastal protection and resilience to future hazards, such as relative sea level rise, sediment erosion, and hurricanes. This study uses the Caminada Headlands geotechnical investigations and monitoring data to determine empirical correlations for deltaic sediment compressibility and develop a validated and calibrated consolidation and subsidence numerical model for future barrier island restoration projects. With this calibrated model, differential settlements associated with sand fill placement can be estimated to design placement elevations to maintain post-construction topography for ecological habitat and restoration requirements and can be used for future beach restoration projects along barrier island shorelines.

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Houser, Chris. „Synchronization of transport and supply in beach-dune interaction“. Progress in Physical Geography: Earth and Environment 33, Nr. 6 (12.10.2009): 733–46. http://dx.doi.org/10.1177/0309133309350120.

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This review considers the role of nearshore processes and morphological change as a flexible and dynamic constraint on the supply and transport of sediment between beach and dune. It is argued that the lack of information in this regard remains a central barrier to the development of a theory of beach-dune interaction that can be translated across scales and between field sites. Existing beach-dune models do not consider how and when sediment gets transferred to the backshore where it becomes available for transport by wind. Rather, existing models largely ascribe regional variations in dune morphology to fixed constraints on beach slope and sediment budget, without explicit recognition of processes involved. Recent (process-scale) transport studies have shown that the transfer of sediment is both spatially variable and temporally intermittent as a result of transport limitations across the beachface. While these studies have identified varied controls on sediment transport and exchange, there remains a limited capacity to predict the evolution of beach-dune systems, largely because the beachface tends to be viewed as a static transport surface without regard to supply or to the changing limits to transport. Following storm erosion, dune recovery first requires that the beach recovers through the onshore migration and welding of nearshore bars, followed by accretion in the backshore to create a supply of sediment for transport by the wind. The dependence of dune recovery on the synchronization of transport events with the recovery of sediment supply in the backshore creates a strong asymmetry in dune recovery that makes barrier island susceptible to widespread erosion and breaching if a change in the frequency or grouping of storm events is capable of resetting the bar system (offshore) before the next extreme storm.

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Escudero, Mireille, Gregorio Posada, Beatriz Edith Vega und Edgar Mendoza. „MONITORING OF THE COASTAL DYNAMICS ON THE SAND SPIT AT TORTUGUEROS BEACH, MEXICO“. Coastal Engineering Proceedings, Nr. 37 (01.09.2023): 52. http://dx.doi.org/10.9753/icce.v37.management.52.

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Sand spits occur worldwide in different shapes, from a single, relatively simple arc to an irregular, crenulated, and complex barrier. Cross-shore and longshore sediment transport often influence spit dynamics (Nagarajan et al., 2015), strongly linked to wave energy and sediment supply. The present analysis focuses on a dynamic and complex spit at Tortugueros beach, a re-entrant bay, 1 km in length, on the Gulf of Mexico. Tortugueros beach is a wave-dominated beach with very fine to fine sand that forms a fairly gentle sloping beach profile. The sediment sources are longshore sediment transport and onshore sandbar migration, while sediment loss is due to long- and cross shore (during storms) transport. The region is micro-tidal, with mean and maximum high tide levels of 0.18 m and 0.92 m above the mean sea level. Given the high dynamics of the Tortugueros beach spit system and the lack of data measured on the beach, a monitoring system was developed to collect field data regularly to help us improve the understanding of the functioning of the coast on this beach, and the international knowledge related to the formation and morphological evolution of this type of spits in other similar beaches around the world.

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NICHOLAS C. BROWN und TIFFANY ROBERTS BRIGGS. „SEDIMENTOLOGY OF BEACHES IN NORTHERN PALM BEACH COUNTY, FLORIDA, USA“. William Morris Davis – Revista de Geomorfologia 1, Nr. 1 (13.08.2020): 29–46. http://dx.doi.org/10.48025/issn2675-6900.v1n1.p29-46.2020.

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Beach nourishment is a common strategy for erosion mitigation that also increases coastal resilience to storm impacts, provides habitat, and supports the economy. Regulations often require that placed sediment closely match the native grain size distribution and composition, however characteristics can vary based on the borrow site. Certain sediment properties will also influence beach slope and other critical beach functions. This study evaluates the 3-dimensional sediment properties and beach morphology of nourished and non-nourished barrier island beaches in northern Palm Beach County, Florida, USA. Surveyed beach profiles were compared with predicted slope based on median grain size. The inlet-adjacent beach managed with annual placement of beneficial use of dredged materials consisted of poorly sorted coarse sand and the steepest measured slope. Sediment was progressively finer and better sorted downdrift with decreasing foreshore slopes. Although sediment near the shoreline is typically the coarsest, clasts were finer than the mid-beach location suggesting that the sampling period coincided with beach recovery and onshore sediment transport of finer material. Sediment at the surface differed from sediment at depth, likely due to the frequent introduction of sediment from various borrow areas compared to the dominance of weathered coquina at depth. The non-carbonate, siliciclastic fraction was primary quartz with few other minerals. The estimated beach slope at the location with the coarsest sediment matched the measured slope. A lower beach slope was predicted for the other locations with finer grain sizes at the shoreline that was attributed to slightly steeper slopes associated with beach accretion. Therefore, complicated spatio-temporal morphodynamics of beaches should be considered when using median grain size from only one sampling event.

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Hoffman, Nick, und Natt Arian. „The Latrobe Group and the 90-million-year beach“. APPEA Journal 53, Nr. 2 (2013): 460. http://dx.doi.org/10.1071/aj12071.

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Carbon dioxide geosequestration requires a detailed understanding of the whole sedimentary section, with particular emphasis on topseals and intraformational seals. Hydrocarbon exploration is more focused on reservoirs but requires a similar basin understanding. This extended abstract reviews the knowledge gained from petroleum exploration in the Gippsland Basin to The CarbonNet Project’s exploration program for CO2 storage. The Ninety Mile Beach on the Gippsland coast is a prominent modern-day sand fairway where longshore drift transports sediments north-eastwards along a barrier-bar system, trapping lake systems behind the coastal strip. This beach is only 10,000 years old (dating to the last glacial rise of sea level) but is built on a platform of earlier beaches that can be traced back almost 90 million years to the initiation of Latrobe Group deposition in the Gippsland Basin. Using a recently compiled and open-file volume of merged 3D seismic surveys, the authors show the evolution of the Latrobe shoreline can be mapped continuously from the Upper Cretaceous to the present day. Sand fairways accumulate as a barrier-bar system at the edge of a steadily subsiding marine embayment, with distinct retrogradational geometries. Behind the barrier system, a series of trapped lakes and lagoons are mapped. In these, coal swamps, extensive shales, and tidal sediments were deposited at different stages of the sea-level curve, while fluvial systems prograded through these lowlands. Detailed 3D seismic extractions show the geometry, orientation and extent of coals, sealing shales, fluvial channels, and bayhead deltas. Detailed understanding of these reservoir and seal systems outlines multi-storey play fairways for hydrocarbon exploration and geosequestration. Use of modern basin resource needs careful coordination of activity and benefits greatly from established data-sharing practices.

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Schmidt, Michael F., Richard Saltlick, Jason A. Johnson und Jose Maria Guzman. „Sustainable Stormwater Management for the Barrier Island Community of Miami Beach“. Proceedings of the Water Environment Federation 2012, Nr. 11 (01.01.2012): 4942–47. http://dx.doi.org/10.2175/193864712811709210.

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Vaske, Jerry J., Robert D. Deblinger und Maureen P. Donnelly. „BARRIER BEACH IMPACT MANAGEMENT PLANNING: FINDINGS FROM THREE LOCATIONS IN MASSACHUSETTS“. Canadian Water Resources Journal 17, Nr. 3 (Januar 1992): 278–90. http://dx.doi.org/10.4296/cwrj1703278.

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LEATHERMAN, STEPHEN P., und ROBERT E. ZAREMBA. „Dynamics of a northern barrier beach: Nauset Spit, Cape Cod, Massachusetts“. Geological Society of America Bulletin 97, Nr. 1 (1986): 116. http://dx.doi.org/10.1130/0016-7606(1986)97<116:doanbb>2.0.co;2.

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Houser, Chris, Phil Wernette, Elizabeth Rentschlar, Hannah Jones, Brianna Hammond und Sarah Trimble. „Post-storm beach and dune recovery: Implications for barrier island resilience“. Geomorphology 234 (April 2015): 54–63. http://dx.doi.org/10.1016/j.geomorph.2014.12.044.

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Carrasco, A. R., Ó. Ferreira, A. Matias und P. Freire. „Natural and human-induced coastal dynamics at a back-barrier beach“. Geomorphology 159-160 (Juli 2012): 30–36. http://dx.doi.org/10.1016/j.geomorph.2012.03.001.

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