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Coastal erosion is caused by a deficit in the sediment balance along coastal shorelines. Within the intertidal waterway of Jacksonville, Florida, the primary processes acting on the shoreline are tidal currents and waves generated by winds and passing vessels. This study focuses on the analysis of vessel-generated waves and their possible effects on different shoreline types. The experiment conducted herein examines variations in turbidity related to passing boats at a specifically selected site location, at which different tidal stages expose three different shoreline types, a non-vegetated scarp, a vegetated scarp and a vegetated area with no scarp in the breaking zone. Statistical analyses were used to quantify relationships between turbidity and wave height within these three different shoreline types. It was determined that both wave heights and the type of shoreline can affect local turbidity levels. Shorelines that contained vegetation experienced significantly less turbidity, than shorelines with no vegetation. Based on the findings here, some preventative measures are suggested to reduce the erosion of intracoastal shorelines into the channel. This would most likely entail boating restrictions or some protective measures to shelter the intracoastal banks.

Shorelines, including the Inner Forth in Scotland, are facing unprecedented challenges with climate change. Rising sea levels mean that stakeholders need to work closely to deliver adaptation, such as the nature-based option of intentionally realigning shorelines landwards to give the sea more space. Drawing from workshops, interviews and surveys with citizens living on the shores of the Inner Forth, and semi-structured interviews with locally active organisations and land-owners, this thesis examines the governance context and methodological issues of citizen engagement in adaptation, with a focus on the use of participatory valuation tools. In particular, I develop citizen-oriented methodological options for integrated and deliberative valuation to address issues of inclusivity and knowledge gaps. The novelty of the deliberative valuation presented here is based on the explicit consideration of awareness gaps from both expert and local perspectives. The results show that even though emerging collaborative institutions are broadening the spectrum of stakeholders engaged in shoreline governance, they do not yet include representative groups of citizens. Empirical material presented here suggests that bridging the citizen engagement gap would potentially support the uptake of nature-based adaptation options, enhance legitimacy of decision-making processes, and bring other-regarding moral principles and biocentric values into decision-making. However, as the valuation results from the citizen workshops illustrate (in resonance with the central tenets of the Intergovernmental science-policy Platform on Biodiversity and Ecosystem Services), commonly applied valuation methods may be too narrow in their framing to capture plural values and world views. Furthermore, the ability of citizens to engage in adaptation is limited by knowledge gaps regarding the local area and the pressures it is facing. The deliberative citizen-oriented approach to valuation developed here led to the emergence of clearer priorities, improved choice model fit and participant confidence, providing empirical evidence to support the premise that deliberation builds citizens' ability to engage in adaptation. In addition to contributing empirical insights on how adaptation governance is unfolding on local scales, this thesis responds to methodological discussions on the use of valuation for citizen engagement in three main ways: 1) it demonstrates that the choice of value framings impacts the engagement outcomes; 2) it illustrates how deliberative valuation can shape citizens' attitudes towards the uptake of adaptation measures; 3) it provides evidence of the specific role that local knowledge plays in improving the outcomes of deliberative valuation.

The major purpose of this study was to examine in detail the anomalous transgressive "boundary" sandstones which generally are present at formation boundaries throughout the Parras and La Popa basins. These extensive sheet-like sandstone bodies are massive, resistant units up to 20 m thick and up to 25 km wide that form the cap of mountains and hogbacks. These are anomalous units because transgressive deposits thicker than 5-10 m are rare in ancient deposits although they are well-documented for some Holocene deposits. For example there are no known thick transgressive deposits in the well-studied cyclic transgressive-regressive sequences in the Cretaceous rocks of the Rocky Mountains. McBride and others (1975) previously interpreted these boundary sandstone bodies to have been laid down as thick transgressive or regressive blanket deposits as the shoreline moved back and forth across the basins in response to variable basin subsidence and sediment input. In order to clarify this interpretation, we selected deposits formed during the latest part of the first deltaic progradation represented by the Cerro Huerta Formation, and at the beginning of the first marine transgression represented by the Cañon del Tule Formation for detailed study. / text

In March 2007 the KwaZulu-Natal coastline was devastated by an extreme storm event. There is international concern that such events are associated with climate change. There is evidence of global changes in climate but there is still uncertainty as to whether they are anthropogenic or part of natural decadal (or longer) cycles. The increase in frequency and intensity of extreme storm events will impact on the sediment dynamics of coastlines and the associated risks need to be modelled and quantifed so that they can be included in coastal planning and management. Durban is a coastal city on the east coast of South Africa and has been used as a case study to identify trends in wave parameters and beach profile volumes. The correlation between profile erosion, waves and tides was explored using singular spectral analysis. The dependence between wave parameters was modelled using copulas. The decadal trends were introduced into these models using a nonstationary generalised extreme value distribution. Numerical models (SWAN, SBEACH, XBEACH) were used to transform the statistical model to near shore waves and estimate the associated erosion. The copula model was used to investigate the relationship between multivariate return periods and erosion return periods. Coastal defence options were reviewed and those appropriate for Durban were identifed. This study provides a review of Durban and Richards Bay's 18 years of Waverider data. It presents wave parameter exceedance statistics and wave height return periods for Durban. Durban's wave data showed increasing trends in maximum significant wave heights, peak wave period, storm event frequencies and a trend towards a more southerly mean wave direction. However, only the increase in peak period and wave direction was statistically significant. The trend in wave direction is considered a potential coastal hazard as it has the potential to increase the littoral drift by 1 % per annum. Durban's beach profiles have shown a long term erosion trend which is due to a combination of wave and sea level trends, and a reduction in sediment supply. The reduction in sediment supply from rivers was found to be both anthropogenic and natural. Storm, wave parameter and sea level trends were estimated to contribute more than 75 % to the total long term erosion. It was found that it takes an average of 2 years for a beach to recover to its pre-storm volume. Different types of coastlines recover at different rates and these recovery rates should be considered in risk assessments. A method for estimating future impacts due to storm and sea level trends has been proposed in the form of a non-stationary copula based statistical model. In general a bivariate return period of wave height and duration was found to approximate erosion return periods, while a method for estimating an analogous multivariate storm and erosion return period was developed. Geotextile sand filled containers were found to be a suitable coastal defence as they satisfy social, environmental and political pressure. / Thesis (Ph.D.)-University of KwaZulu-Natal, Durban, 2012.

Holocene shoreline sequences and associated shelf stratigraphy are described from a high gradient, high wave energy shelf offshore the central KwaZulu-Natal and northern KwaZulu-Natal coastlines. These are examined using high resolution single-channel seismic and multibeam bathymetric means in order to describe the shallow stratigraphy and seafloor geomorphology of each area. The development and preservation of two distinct planform shorelines at -100 m (northern KwaZulu-Natal) and -60 m (northern KwaZulu-Natal and central KwaZulu-Natal) is described. The shallow seismic stratigraphy of northern KwaZulu-Natal comprises three seismic units (Units 1-3) corresponding to calcarenite barriers (Unit 1), back barrier lagoonal sediments (Unit 2) and the contemporary highstand sediment wedge (Unit 3). At intervening depths between each shoreline the shelf is characterised by erosional surfaces that reflect ravinement processes during periods of slowly rising sea level. Where shorelines are not preserved, areas of scarping in the ravinement surface at depths coincident to adjoining shorelines are apparent. These areas represent rocky headlands that separated the sandy coastal compartments where the shorelines formed and are a function of the high gradient. In central KwaZulu-Natal where the shelf is notably wider and gentler, shoreline building was more intense. Five major seismic units are identified (Units 1-5) with several subsidiary facies. The formation of the -60 m barrier complex (Unit 2) in central KwaZulu-Natal was accompanied by the simultaneous formation of a back-barrier system comprising lake-lagoon depressions (Unit 3) and parabolic dune fields aligned to the local aeolian transport direction, formed on a widened coastal plain. On the seaward margins of the barrier, gully and shore platform features developed coevally with the barrier system. Several relict weathering features (Unit 4) are associated with the barrier and reflect similar processes observed in contemporary aeolianite/beachrock outcrops on the adjacent coastline. The two submerged shoreline sequences observed are attributed to century to millennial scale periods of stasis during which shoreline equilibrium forms developed and early diagenesis of beachrock and aeolianite occurred. These extensive phases of shoreline development are thought to have occurred during periods of stillstand or slowstand associated with the Bølling-Allerod Interstadial (~14.5 ka BP) and the Younger Dryas Cold Period (~12.7-11.6 Ka BP). Shoreline preservation in such an environment is considered unlikely as a result of intense ravinement during shoreline translation, coupled with the high energy setting of the KwaZulu-Natal shelf. Preservation of both the 100 m and 60 m shorelines occurred via overstepping where preservation was promoted by particularly rapid bouts of relative sea-level rise associated with meltwater pulses 1A and 1B (MWP-1A and -1B). This was aided by early cementation of the shoreline forms during stillstand. Differences in shelf setting have led to variations in the style of barrier preservation and associated transgressive stratigraphies between the central KwaZulu-Natal and northern KwaZulu-Natal shelves. The main differences include a much thicker post-transgressive sediment drape, higher degrees of transgressive ravinement and an overall simplified transgressive system’s tract (TST) architecture on the steeper and narrower continental shelf of northern KwaZulu-Natal. In comparison, the central KwaZulu-Natal shelf’s 60 m shoreline complex reflects more complicated equilibrium shoreline facets, large compound dune fields formed in the hinterland of the shoreline complex, higher degrees of preservation and a more complicated transgressive stratigraphy. / Thesis (M.Sc.)-University of KwaZulu-Natal, Durban, 2013.

Thesis (M.Sc. Earth and Ocean Sciences)--University of Waikato, 2008. / Title from PDF cover (viewed September 18, 2008) Includes bibliographical references (p. 121-123)

Thesis (M.S.) -- Mississippi State University. Department of Computational Engineering. / Title from title screen. Includes bibliographical references.

Thesis (Ph. D.)--Australian National University, 1980. / Includes bibliographical references (leaves 343-357).

Thesis (doctoral)--Chalmers tekniska högskola, 1983. / Errata slip inserted. Summary in English. Includes bibliographical references (p. 164-171).