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West Reflex Lake is a hypersaline lake in the Canadian Great Plains. The lake contains four types of shoreline carbonate structures: isolated pinnacles, bioherms (aggregates of pinnacles), laminated coatings, and beachrock. This study investigates the processes of formation of West Reflex Lake’s shoreline carbonates. A variety of petrographic and geochemical techniques were used to characterize the texture, mineralogy, and chemistry of the carbonates. The shoreline carbonates formed as a result of biotic and abiotic precipitation at the site of saline springs that supply Ca2+ to the lake. Evidence for biologically-influenced precipitation includes strong epifluorescence, presence of micrite cements, and abundance of microbial filaments. Abiotically-precipitated cements formed due to groundwater inflow. The isolated pinnacles and bioherms formed as a result of groundwater percolating through a framework of microbial filaments, whereas the laminated coatings formed as a result of calcification of coherent microbial mats adhering to a substrate. / May 2017

Heaps of fire cracked stones is an apparent feature of the Scandinavian Bronze Age. The heaps are built of stones cracked by fire and then placed in different constructions. The heaps are placed in different contexts in the Bronze Age landscape and for a long time, research neglected this site category owing to that the heaps were not considered important enough to dig. During the 1980s-90s the interest for the heaps of fire cracked stones increased and it became a wellresearched although debated site category. Earlier research has interpreted the heaps to be on the hillslopes in the landscape. This study’s research aims to understand the relation between shorelines and the placement of fire cracked stone heaps. This will be done through a landscape study of Uppland. The study indicates that the pattern in the distribution of heaps of fire cracked stones creates a correlation with the shoreline of the time the heaps were built, through their placement in the landscape. By creating a dynamic shoreline displacement, the essay will be able to look at the landscape in a more detailed way and will be able to investigate the relation between the heaps and the water edge. Through excluding the heaps that are under the waterline it is possible to in general determine the earliest possible production date. The fire cracked stone heaps have earlier been categorised to the Scandinavian Bronze Age but this research argues that some of the heaps should belong to the Neolithic Age as well.

Le double tombolo de Giens, situé dans la ville de Hyères, dans le sud-est de la France, est une formation géomorphologique unique et rare dans le monde, qui relie l'île de Giens au continent. Il a été principalement formé en raison de la diffraction d'onde et de la réfraction par les îles. Il se compose de deux parties : la branche ouest (plage de l'Almanarre) directement en face du golfe de Giens et la branche orientale située sur la côte ouest de la baie d'Hyères. Ces parties sont séparées par l'étang salé des Pesquiers. La partie orientale du tombolo de Giens s'étend sur plus de dix kilomètres de l'embouchure de la rivière Gapeau au nord jusqu'à la plage de La Badine au sud. Les plages le long du tombolo oriental, en particulier les plages de Ceinturon et de Bona, sont sujettes à l'érosion et au rétrécissement en raison de causes naturelles et d'interférences humaines, mais les interventions anthropiques dominent.Afin d'atténuer ou d'empêcher l'érosion côtière, diverses structures côtières ont été utilisées le long du tombolo oriental de Giens. Elles ne peuvent résoudre l'érosion locale que dans certains cas, mais peuvent aussi engendrer des effets indésirables. Les structures côtières qui interfèrent avec le transport des sédiments le long des côtes, non seulement entraînent un déficit de sédiments et l'érosion dans la dérive en aval, mais aussi effacent le paysage environnant des plages.Les principaux objectifs de cette thèse étaient de mieux comprendre les processus physiques sous-jacents à la morpho-dynamique et d'anticiper l'évolution future du tombolo oriental de Giens en réponse aux différentes actions et interventions le long de la côte. La mesure structurelle la plus appropriée a été proposée non seulement pour protéger les plages de Ceinturon et Bona et pour stabiliser le rivage à long terme, mais aussi pour maintenir l'accessibilité ou l'esthétique des plages. Les modèles numériques MIKE 21 et LITPACK de DHI sont utilisés pour atteindre ces objectifs. L'évolution historique et future à long terme du rivage est également évaluée et prédite en utilisant la combinaison de techniques de télédétection, de système d'information géographique (SIG) et de régression linéaire. Ces modèles numériques ont été testés de manière satisfaisante sur des données historiques disponibles, car ils pouvaient reproduire l'hydrodynamique observée et l'évolution côtière.En particulier, une nouvelle approche suggérée pour simuler la présence de posidonies et divers types de fonds marins est présentée dans ce travail. Les résultats numériques interprètent le rôle ainsi que l'impact du changement de vent, la variation saisonnière, les événements extrêmes, les herbiers de posidonies, l'élévation du niveau de la mer et le ré-ensablement de la plage sur l'évolution morphologique du tombolo oriental de Giens. De plus, les résultats obtenus démontrent que les digues sous-marines jouent un rôle très important dans la protection des plages de Ceinturon et Bona, elles permettent de réduire efficacement la hauteur des vagues, la vitesse du courant et le transport des sédiments ainsi que contrecarrer le retrait du rivage dans toutes les conditions des vagues, à l'exception des tempêtes semi-centenaires et centennales pour lesquelles une certaine érosion persiste. Combinées à des ré-ensablements périodiques mais limités en espace et en temps, elles semblent constituer le meilleur compromis de protection à moyen et long terme. / The double tombolo of Giens, located in the town of Hyères, South East of France, is a unique and rare geomorphological formation in the world, which links Giens Island to the continent. It was mainly formed due to the wave diffraction and refraction by the islands. It consists of two parts: the western branch (Almanarre beach) directly facing the Gulf of Giens and the eastern branch lying on the western coast of Hyères bay. These parts are distinctly separated by the salt pond of Pesquiers. The eastern part of Giens tombolo extends over more than ten kilometers from the mouth of Gapeau river in the north to La Badine beach in the south. The beaches along the eastern tombolo, especially Ceinturon and Bona beaches are subject to beach erosion and beach narrowing due to both natural causes and human interference, but anthropogenic interventions are still dominant. In order to mitigate or prevent coastal erosion, various coastal structures have been used along the eastern Giens tombolo. They can only solve local erosion in some cases, but may also trigger some undesirable effects as well as disadvantages. Even the shore-normal structures that interfere with longshore sediment transport, not only result in the deficit of sediment and erosion in the downstream drift, but also blot out surrounding landscape of the beaches.The main objectives of this study was to better understand the physical processes underlying the morphodynamics, and also anticipate future evolution of the eastern Giens tombolo in response to different actions and interventions taking place along the coast. Thereof, the submerged breakwater (SBW) was proposed to not only protect the Ceinturon and Bona beaches and stabilize the shoreline in the long term, but also maintain beach amenity or aesthetics. DHI’s MIKE 21 and LITPACK numerical models are used in order to achieve these above-mentioned objectives. Additionally, the historical and future medium-term shoreline evolution along the eastern Giens tombolo is also evaluated and predicted by using the combination of remote sensing, geographic information system (GIS) techniques coupled with the Digital Shoreline Analysis System (DSAS) along with linear regression method. These numerical models were satisfactorily tested available historical data, as they could reproduce the observed hydrodynamics and coastal evolution. Especially, a novel approach suggested to simulate the presence of Posidonia seagrass and various types of seabed is presented in this work. The numerical results interpret the role as well as impact of wind change, seasonal variation, extreme events, Posidonia seagrass, sea level rise, and beach nourishment on the morphological evolution of the eastern Giens tombolo. Moreover, the results obtained strongly demonstrate that the SBWs play a very important in protecting Ceinturon and Bona beaches to a certain degree, viz. effectively reducing the nearshore wave heights, current speed and sediment transport as well as counteracting the retreat of the shoreline under the wave conditions apart from the semi-centennial and centennial storms.

Pilot Valley, located in the eastern Basin and Range, north of Wendover, UT, contains numerous shorelines and depositional remnants of late Pleistocene Lake Bonneville. These remnants present classic ground penetrating radar (GPR) targets due to their coherent stratification, low clay, low salinity, and low moisture content. Three-dimensional (3D) GPR imaging can resolve fine-scale stratigraphy of these deposits down to a few centimeters. While lake levels fluctuated due to flooding events, climatic changes were the dominant factor in controlling lake levels. In Pilot Valley, the paleowind entered from the northwest, with storms coming from the south, and circulated clockwise around the basin, forming offshore sand bars. On the western side of the valley, a uniquely well-preserved interpreted regressive phase beach deposit, dated late Pleistocene, is hypothesized to have been a point bar shortly after the Provo Shoreline period. 3D GPR data, measured stratigraphic sections, cores, mineralogical analysis, and the collection of gastropod samples for radiocarbon dating constrain a reconstruction of the deposit's depositional environment and local paleoclimate for Lake Bonneville. The GPR images, visualized with state-of-the-art petroleum industry tools, reveal fine-scale stratigraphic detail that can be analyzed using seismic stratigraphy concepts. Our study provides a comprehensive model for ancient pluvial lake-shore depositional environments in a Basin and Range setting using an integration of geological and geophysical data.

Mullet Key is a right angle barrier island located at the mouth of Tampa Bay, west-central Florida. Based on historical shoreline data from 1873, the Gulf (west)-facing section of the beach has been dynamic illustrating large beach advances and retreats of up to 500 m on a decadal scale, while the south (channel)-facing section of the beach has shown to maintain a stable shoreline. This study focuses on the morphodynamics of the Gulf-facing beach. Since the 1920s, most of the Gulf-facing beach has been accreting except at the southern end near the Tampa Bay main channel. However, over the past 17 years, severe beach erosion has occurred along the northern portion of the island while accretion occurred along the middle portion. The southern end of the island has been maintained through artificial beach nourishments. Analysis of 27 aerial images from 1942 to 2014 revealed that the above large shoreline variations can be explained by the initiation, emergence, landward migrating, shoreline attachment, and post-attachment beach adjustment of the swash-bar complex on the Bunces Pass ebb delta. Two cycles of the swash-bar complex attachments with a period of approximately 30 years were identified from the aerial photos spanning 72 years. Twenty-eight beach-profiles spanning the 4 km Mullet Key Gulf-facing beach were surveyed 7 times on a bi-monthly basis from March 2014 to February 2015 to quantify the recent rapid changes, and to assess a yearly rate of shoreline change. Beach-profile analyses showed that the 120 m beach at the north-most tip in the immediate vicinity of Bunces Pass has lost a small amount of sediment. The 360 m beach to the south has gained some sediment. The 670 m stretch of beach further south has had significant shoreline retreat at a rate of 10-15 m/year. The 2,400 m section southward has experienced some gain of sediment, while the 370 m nourished beach at the southernmost tip has had slight retreat. This beach change pattern illustrates a diverging longshore sediment transport. Nearshore wave and current conditions were measured during a cold front passage in December 2014 to quantify the hydrodynamic processes that induced the diverging longshore transport. Three wave and current gauges were deployed along the eroding and accreting sections. The hydrodynamic data reveal that the longshore transport divergence is caused by diverging flood tidal flow into Bunces Pass to the north and Tampa Bay channel to the south. Furthermore, the waves in front the eroding beach were higher than the adjacent accreting beach.

The objective of this project was to document the status of oysters, Crassostrea virginica, from non-reef habitats throughout Tampa Bay, Florida, and assess the ecosystem contributions of those populations relative to reef-dwelling oysters. The aspects of oyster ecology studied here include condition, prevalence and intensity of disease (Perkinsus marinus - dermo), reproductive activity (including stage, fecundity, and juvenile recruitment), adult oyster density, and the faunal community associated with the oysters. The predominant source of variation was seasonal, with lesser contributions among sites, and in most cases, little or no effect of the habitat type. Oysters populations from each habitat recruit juvenile oysters, produce mature individuals, and contribute viable gametes at the same magnitude with similar seasonality. The associated faunal communities were also largely similar between habitats at any given site. Measures of oyster density, combined with estimates of the total available habitat, suggest that natural oyster reefs may represent only a small portion of the total oyster community in Tampa Bay, while oysters associated with mangrove habitats and seawalls are probably the most abundant in the bay. Additional mapping and quantification of these habitats would help to define their bay-wide ecosystem-services value. Restoration projects, though small in size relative to other habitats, do provide alternative and additional habitat with comparable value to other oyster-bearing habitats.

The inner continental shelf off the western half of the barrier island Fire Island, NY, is characterized by a series of obliquely oriented shoreface-connected ridges. The long-term historic shoreline record shows persistent undulations in shoreline shape at an alongshore scale similar to the alongshore scale of the ridges. This suggests that the ridges affect the wave transformation, alongshore sediment transport and corresponding shoreline change. These processes are investigated by utilizing the SWAN (Simulating WAves Nearshore) model, forced with realistic wave parameters, on a simplified, synthetic bathymetry replicating the scales of the shoreface-connected ridges. Results indicate that the relative magnitude of alongshore variations of modeled waves, alongshore transport, and the corresponding shoreline change are highly correlated with the relative orientation of the incoming waves to the ridges. Alongshore variations in both wave height and direction along the breaker line are much stronger when the predominant wave direction is along the main axis of the ridges rather than perpendicular to the ridge crests. This pattern of wave height variation is further explained by evaluating the directional energy spectrum and using a reverse ray-tracing technique. The gradients of the alongshore sediment transport, which lead to shoreline change, also appear to be stronger for waves with an angle of incidence similar to the ridge orientation. These results help explain the relationship between the oblique shoreface-connected ridges and the corresponding shoreline changes and shed light on the connection between the inner-shelf ridges and persistent shoreline undulations for the Western portion of Fire Island.

This study seeks to examine whether a relation can be found between the number of shoreline exemptions and the development of Umeå municipalities population, or not. The weight of this paper will be focusing on the importance of place attractiveness and social place identity for people’s desires and ambitions to live near a lake or the coast. The policies of planning will also be highlighted in order to receive greater understanding of why people apply for shoreline exemptions. Four semi- structured interviews with planners from Umeå municipality were therefor held with the ambition to complement the quantitative findings of the development of exemptions. The presenting results indicates that an increase of shoreline exemptions can be stated as well as the actions within the exemptions. The population has steadily increased trough out the studied years, 2014-2017. The relation between these findings can be argued have had a similar development, but we cannot be sure to say that they solely affect each other. Therefor the findings will be explained by earlier research regarding residential preferences, the desire to live with water view and planning policies that responds to these factors.

A investigação dos movimentos morfológicos da embocadura de canais e de linhas de praia pode ser instrumental para a descrição da influência de processos costeiros de curto prazo. A Lagoa do Peixe (LP) encontra-se dentro do Parque Nacional da Lagoa do Peixe (PNLP), 344 km², litoral médio da Planície Costeira do Rio Grande do Sul. O objetivo desse trabalho foi descrever o comportamento morfodinâmico da embocadura do canal, sua instabilidade, geometria, caracterização geomorfológica e a análise da variabilidade da posição da linha de praia adjacente, entre 1987 e 2009. A partir do conjunto de imagens LANDSAT (1973 a 2009) e de técnicas de geoprocessamento, foram analisadas as características morfológicas e a dinâmica do canal. O movimento de curto prazo na linha de praia foi avaliado a partir de imagens LANDSAT TM vetorizadas (1987 e 2009) pelo método dos pontos extremos. Os resultados foram comparados a modelos numéricos, possibilitando a descrição de um canal de maré com um mecanismo de assoreamento morfodinâmico. A região do PNLP sofre a influência da variabilidade do seu regime de precipitação sazonal, onde o maior volume de chuvas ocorre no inverno. Esse regime pluviométrico é associado às correntes litorâneas de SW, que tem de maior capacidade de deriva que as correntes de NE, mais frequentes no verão. A abertura natural do canal ocorreu no biênio: 1997-1998, onde os totais de precipitação anual foram de 400 mm acima da média para a região do PNLP (1265 mm). O assoreamento do canal da LP esta relacionado à diminuição do volume de chuvas. Com a aproximação do verão, o transporte de sedimentos, promovido pelos ventos e correntes de NE, é menos competente, porem de maior frequência, contribuindo para a formação de pontais que se desenvolvem no sentindo das correntes. A análise da variabilidade da posição da linha de praia adjacente ao PNLP acusou um processo progradante ao norte do canal (até 40 m) e retrogradante ao sul (máximo 80 m). Esses resultados são compatíveis com outros resultados oferecidos pela literatura respectiva. / The investigation of morphological change in lagoonal inlets and shorelines can be instrumental to describe the influence of short term coastal processes. The Lagoa do Peixe (LP) is set within the Parque Nacional da Lagoa do Peixe (PNLP), 344 km², located on the mid-section of the Rio Grande do Sul coastal plain. The objective of this work was to describe the morphodynamic behavior of inlet, its instability, geometry and geomorphologic characteristics, as well as an analysis of the variability of the adjacent shoreline position, between 1987 e 2009. A set of LANDSAT images (from 1973 to 2009) and geoprocessing techniques were employed to analyze the morphologic characteristics and dynamics of the LP channel. Short term movements of the shoreline were evaluated from the vectorized LANDSAT TM imagery (1987 and 2009), using the extreme points method. The results were compared to numerical models, which made it possible to describe a tidal inlet with a morphodynamic sedimentation mechanism. The PNLP region is influenced by the variability of its precipitation regime, in which larger precipitation volumes occur in winter. This pluviometric regime is associated to the longshore SW currents which have a greater drifting capacity than the NW currents, more frequent in summer. The natural opening of the channel occurred in the two-year periods of 1997-1998, where total annual precipitation was 400 mm above the average for the PNLP region (1265 mm). LP channel sedimentation is related to the lowering of rain volumes. With the progression of summer, sediment transport promoted by wind and NE currents, is less competent, although more frequent, contributing to the formation of spits that develop siding the currents. Analyses of the variability of PNLP adjacent coastline position indicated a progradation process to the north of the channel (up to 40 m) and a retrogradation process to the south (maximum of 80 m). These results are compatible with other assessments offered by the respective literature.