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The development of tools and techniques used in paleoenvironmental studies is important for the advancement of geoarchaeological research. Geoarchaeological studies of ancient harbours involve the integration of paleoenvironmental data with archaeological findings, allowing for a more comprehensive understanding of site development and regional maritime trade. This dissertation highlights and/or explores novel applications of microfossils and micro-X-ray fluorescence (μXRF) core scanning data in paleoenvironmental reconstructions within three ancient harbour studies. Foraminifera, diatom, pollen, μXRF, carbon stable isotope, and radiocarbon dating results from underwater cave sediments on the eastern coast of the Yucatán Peninsula indicate that the region’s wetlands developed between 1157 BCE and 312 CE. Continued sea-level rise after ~312 CE allowed canoe access through a channel from the Caribbean Sea to Muyil, a Classic Maya maritime port site. Development of the wetlands may have implications for increased maritime trade on the Yucatán’s eastern coast during the Postclassic (925–1550 CE). This study demonstrates the importance of karst cave systems for obtaining paleoenvironmental records and provides a first assessment of the diatom community that has been transported into the sampled cave system. The novel application of epiphytic foraminifera as biostratigraphic indicators was investigated at Caesarea, Israel. Benthic foraminifera assemblages indicated that the emplacement of hard harbour structures along the sandy coast between 21–10 BCE altered the environmental conditions and impacted the nearby ecological communities. Epiphytic foraminifera, in particular Pararotalia calcariformata, were found to be useful indicators for the timing of harbour construction at Caesarea. μXRF and magnetic susceptibility results also supported the presence of increased harbour material (i.e., kurkar and volcanic ash) in offshore sediments over time. This study demonstrates that epiphytic foraminifera can be cost-effective biostratigraphic indicators in geoarchaeological studies. Results also confirm that P. calcariformata is endemic to Israel and is not a recent arrival following the opening of the Suez Canal. Foraminifera, testate amoebae, μXRF, and radiocarbon dating results from sediment cores collected from two lagoons, Khor Al Balid and Khor Rori, on the southern coast of Oman indicate that the lagoons closed off from the sea between the 12th and 15th centuries CE. Prior to lagoon formation, these two sites formed natural harbours that were the locations of major maritime trade ports. Progressive siltation and sand accumulation along the coastline after the 15th century likely impacted shipping activities, contributing to abandonment of the city near Khor Al Balid. Evidence of a marine overwash event across most cores from both sites dating to the 18th–19th century CE suggests that an extreme wave event (e.g., tsunami or large tropical cyclone) may have also contributed to the decline of the city. The results of this study provide an important paleoenvironmental context for previous archaeological findings. / Dissertation / Doctor of Philosophy (PhD)

Interferometric Synthetic Aperture Radar (InSAR) is an established technique which has been applied to Earth surface displacement analysis and topographic reconstruction. Two complex coherent SAR acquisitions of the same scene are combined to form an interferogram from which surface displacement or terrain measurements are made. The similarities between both SAR signals is captured in the coherence and its magnitude is determined by the spatial separation between acquiring antennas and the changes (if any) to the physical characteristics of the scattering target in the duration between both SAR acquisitions. Both of these products derivable from the interferometric process have been applied in this study with the aim of enhancing monitoring and assessing changes in the coastal environment, with emphasis on the coastal geomorphology. A combination of remote sensing data acquired for Montrose Bay, NE Scotland, has been used to analyze changes to the geomorphology of the beach and dune system in terms of sediment volume analysis, erosion and accretion processes and shoreline changes over a short-term period of 4 years. The interferometric coherence was applied to detect changes to the dune morphology, which have been actively eroding at the southern flank of the Bay. The interferometric analysis presented in this thesis was based on SAR data acquired by the Sentinel-1 SAR antenna and the results demonstrated the limitations of the sensor for terrain mapping and DEM reconstruction. In addition, the significance of the vegetation on the interferometric coherence was demonstrated. However, the results have shown that temporal baseline remained a significant consideration in the application of interferometric coherence in highly dynamic environments such as the coastal environment.

This dissertation presents the detailed results of investigations into the coastal geomorphological effects and sedimentation processes associated with a recent large tsunami event which took place on the 12th December 1992 in Flores, Indonesia, and the stratigraphical and sedimentological study of a widespread sand layer preserved in coastal sedimentary sequences along the eastern coast of Scotland representing a low-frequency, high-energy marine event, which took place at circa 7,000 radiocarbon years B.P. With modern alalogues, established in this dissertation, of both tsunami and storm surge sedimentary characteristics and sedimentation processes as the key, together with high-resolution sedimentological evidence obtained from the circa 7,000 radiocarbon years B. P. event, competing hypotheses of the likely causes of the marine flooding by either a tsunami or storm surge event are tested. It is concluded that the circa 7,000 B. P. marine flooding event was a tsunami, believed to have been generated by one of the world's largest submarine landslides in the Norwegian Sea - the Second Storegga Slide. The particle size composition of tsunami sediments is found to vary from well sorted to poorly sorted and is controlled by both the characteristics of the source sedement (local coastal sediments) and sedimentation processes associated with tsunami inundation. Tsunami sediments deposited on land are believed to form continuous and discontinuous sedimentary sheets ascending up to levels distinctively higher than contemporary sea levels and to contain a general landward-fining trend and multiple sets of grading (fining-upward) sequences, reflecting spatial changes in particle size composition. A conceptual model of coastal tsunami sedimentation is established including processes of seaward and landward sediment movements, episodic rapid deposition, sediment accumulation and erosion.

This thesis is missing page 123, no other copy of the thesis has this page. -Digitization Centre / This research provides the first detailed study of the coastal geomorphology of Playa Guiones, Guanacaste Province Costa Rica. Playa Guiones is located within a tropical wet/dry climate necessitating that field work is completed in both seasons to ensure a broad understanding of the coastal characteristics. The research commenced February 2005 with site selection and preliminary field work. During June 2005 a detailed real-time kinematic GPS survey and beach inventory (sediment, rock and vegetation) was conducted. During a third field session a comparison was made between the current observed coastal characteristics and those observed during the two other field seasons. Playa Guiones is composed of primarily fine grained sand and carbonate shell material. Rock samples collected adjacent to the southern headland on the rocky shore platform consisted of limestone and finely grained, interbedded sandstone and siltstone. Adjacent to the northern headland on the rocky shore platform the rock consisted of sandstone. Playa Guiones displays some temporal variability which may be linked to the wet and dry seasons. On initial inspection Playa Guiones appears to have the characteristics of an embayed beach but more detailed inspection illustrates that Playa Guiones has many characteristics that are contradictory to a typical embayed beach. Although Playa Guiones lies on a convergent margin it has many characteristics of a divergent margin coast. This study is significant because it provides important baseline information for future work. Playa Guiones is located on the Nicoya Peninsula where a large seismic gap, which last fully ruptured in 1950, is known to exist. The baseline data will be very useful subsequent to any future earthquake event for measuring change that occurs along this rapidly developing coastline. The methodologies employed in this study provide much more detail information than is typically collected in gee-indicator studies which often only measure several profiles along a beach to create a digital elevation model rather than the 3 m gridding distance used in this study. / Thesis / Master of Science (MS)

Trinity, East, and Wine Islands make up the eastern half of the Isles Dernieres barrier arc in south-central Louisiana. Formed following the abandonment of the Lafourche delta complex, subsidence and storm erosion have led to rapid deterioration of the system. Since 1887, the land area of the islands has decreased seventy-seven percent, and the gulf shoreline has retreated landward more than a kilometer. Wave ravinement on the shoreface of the islands is responsible for the most sediment loss; liberated sediment travels longshore to tidal inlets. The dominant ebb tidal currents then transport the sediment to where it is deposited in ebb tidal deltas or carried to the west, out of the system. A large lobe of sediment bypassing Cat Island Pass is entering the system from the eastern lower shoreface, which helps replace some of the sediment lost through wave ravinement to the upper shoreface.

As formas naturais do relevo costeiro são resultantes da atuação e interação de processos continentais, oceânicos e atmosféricos. Dentre as diversas feições costeiras destacam-se as falésias e, nesta tese, serão discutidas estas feições esculpidas na Formação Barreiras, sendo esta uma vasta área sedimentar que se estende desde o estado do Rio de Janeiro até o estado do Amapá. Há um grande conjunto de elementos em interação atuando na morfogênese e evolução das falésias e estes são considerados dentro de uma perspectiva de análise sistêmica, sendo estes agrupados e caracterizados como elementos de um Sistema Natural, considerando-se o sistema como um conjunto formado por materiais, processos e formas, tratados, nesta tese, como um sistema geomórfico dinâmico com entrada (inputs) e saída (outputs) de energia e materiais identificáveis, dirigidos e controlados pelas condições ambientais, no qual inúmeros tipos de processos ocorrem simultaneamente. Estudos teóricos e de campo foram realizados em Beberibe-CE, Mucuri-BA e Tibau do Sul-RN e possibilitaram a observação e identificação de características e indícios da morfogênese e evolução das falésias, permitindo a proposição de uma classificação, dentro de um quadro regional da Formação Barreiras, destas feições em: 1) falésia precedida por praia; 2) falésia não precedida por praia. / Natural forms of coastal relief are the result of the action and interaction of continental, oceanic and atmospheric processes. Among various coastal features, cliffs stand out and in this thesis, we discuss these features carved into Formação Barreiras, which is a vast sedimentary area stretching from Rio de Janeiro to Amapá State. There is a large set of elements in interaction taking part in the morphogenesis and in the evolution of cliffs which are considered here within the perspective of a systemic analysis. These elements are classified and characterized as elements of a \"Natural System\", considered system as a whole formed by materials, processes and forms, treated, in this thesis, as a dynamic geomorphic system with inputs and outputs of strenght and materials identifiable, directed and controlled by environmental conditions, in which numberless types of material processes occur simultaneously. Theoretical and field studies performed in Beberibe-CE, Mucuri-BA and Tibau do Sul-RN, allowed us to observe and identify characteristics and evidences of cliffs morphogenesis and evolution, making possible we propose a classification of these features, within a regional framework of Formação Barreiras: 1) cliffs preceded by a beach; 2) cliffs not preceded by a beach.

como uma tarefa importante das ciências relacionadas aos ambientes litorâneos. É importante progredir com os estudos, por meio da revisão e reinterpretação dos dados já existentes e da proposição de dados adicionais que elucidem as divergências que permeiam o delineamento das curvas de variação do nível do mar na costa brasileira e melhorem o diagnostico dos paleoníveis. A importância desses pesquisas reside no fato de que as variações contribuíram diretamente na formação e evolução das áreas costeiras. O município de Ubatuba possui grande potencial para a ocorrência de indicadores biológicos e geomorfológicos de paleoníveis marinhos, ainda pouco estudados em todo o litoral paulista. Estudos prévios que encontraram paleoindicadores biológicos de variações holocênicas do NM em alguns costões rochosos de Ubatuba, são um bom exemplo desse potencial. No presente trabalho avaliou-se 3 costões no município citado, quanto a suas características geomorfológicas e geológicas, e suas potencialidades para a ocorrência de indicadores de variação do NM. Os resultados apresentados permitem concluir que esses costões apresentam características peculiares que permitem o desenvolvimento e preservação de registros de NM. Pode-se inferir que as bandas de ouriços pormenorizadas no presente estudo definem níveis marinhos pretéritos, bem como os níveis de plataformas de abrasão marinha inativas aqui caracterizados. Tanto as plataforma quanto a presença das bandas sugerem pelo menos três estabilizações de NM mais alto que o atual, o que corrobora a literatura. Para estabelecer correlações entre as áreas estudas e delas com outras áreas do município, serão necessários estudos futuros, que contemplem ainda a datação de amostras de restos biogênicos, para que se possa relacionar os dados espaciais aqui apresentados com referencias temporais. / Responding to issues related to marine paleolevels reiterated increasingly as an important task of the science related to coastal environments. It is important to make progress with the studies through the review and reinterpretation of existing data and additional data proposition elucidating the differences that permeate the design of the variation curves sea level on the Brazilian coast and improve the diagnosis of paleolevels. The importance of these studies lies in the fact that changes have contributed directly to the formation and evolution of coastal areas. The city of Ubatuba has great potential for the occurrence of biological and geomorphological indicators of marine paleolevels, still understudied throughout the São Paulo coast. Previous studies have found that biological paleoindicadores of Holocene variations of sea level in some rocky shores of Ubatuba, are a good examples of this potential. In the present study we evaluated three rocky shores in Ubatuba as its geomorphological and geological features, and its potential for the occurrence of NM variation indicators. The results allow us to conclude that these shores have peculiar characteristics that enable the development and preservation of NM records. It can be inferred that the hedgehogs bands detailed in this study define tenses sea levels as well as levels of inactive marine abrasion platforms here characterized. Both the platform and the presence of the bands suggest at least three higher NM stabilizations that the current, which corroborates the literature. To establish correlations between them and studied areas with other areas of the municipality will require further study, still contemplating the dating of samples of biogenic remains, so that you can relate to the spatial data presented herein with temporal references.

The machair is a coastal grassland system found only in parts of northern and western Scotland and Ireland. Despite its limited geographic distribution, machair landscapes have high ecological, geomorphological, and cultural significance, as recognised by numerous conservation designations and legislation. In January 2005 a severe storm caused extensive damage in the Outer Hebrides, drawing attention to the sensitivity of the machair coast to erosion. The aim of this research was to investigate variations and trends in the sensitivity of three field sites within the South Uist machair to soil and coastal erosion, and to interpret measured change alongside analysis of historic climate data. Two of the sites selected, Cille Pheadair and Staoinebrig, experienced some of the most dramatic geomorphological changes associated with the 2005 storm, while the third site, Milton, appeared to be more resistant to change. A combination of fieldwork, laboratory tests, and archive work was used to obtain and analyse information about sediment budgets, shoreline indicator change, and sediment erodibility, along with contextual climatic information. A key result of this work is the provision of a detailed framework of short-medium term cyclical changes and fluctuations in the coastal change, which provides a context for interpreting and responding to longer term trends in erosion and/or accretion. Results indicated high spatial and temporal variability in the erodibility of machair soils and landforms, with no clear relationship between climatic factors and rates of erosion. Considerable short-term variations in beach volume and the position of dynamic shoreline indicators caution against the relaibility of using ‘snap-shot’ historic datasets to infer long-term rates of change. It is proposed that the machair landscape currently functions in a state of highly dynamic equilibrium, which has been maintained over the last ~130 years. While storm events such as the January 2005 storm have locally dramatic consequences, they do not appear to have disrupted the overally physical and ecological functions of the system. This contribution is particularly timely given current concerns for the future of the machair landscape under predicted sea-level and climate change scenarios, and the potential for inappropriate hard-engineering responses to the perceived risk.

Optically stimulated luminescence (OSL) dating beach ridge sediments is one method for resolving barrier island growth at intermediate scales (decades-centuries), information that is lacking for Louisiana. This research combines OSL, GPR, aerial imagery, and cores to document temporal and spatial evolution of a Louisiana barrier island. Grand Isle is composed of beach ridges organized in distinct, unconformable sets that began forming 0.75 ka until 0.575 ka when deposition ceased, the ridges were partially eroded, and deposition resumed in a more eastward direction. The central ridges formed between 370±30 and 170±10 years ago at a rate of one ridge every 11.6 years with sand from the eroding Caminada headland that, with flanking barriers, forms the Bayou Lafourche transgressive depositional system. Grand Isle’s lithosome (92,600,000 cubic meters) requires an annual longshore transport of 128,625 cubic meters. The lithosome thickness (10 meters) and steady sediment supply stabilize the island relative to other Louisiana barriers.