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• First map of primary and secondary chert sources in nothern Apulia. • Multivariate statistics applied to a compositional mixed dataset of chert. • Peschici Fm. mines were better differentiated than Maiolica Fm. ones. • Polygenic secondary chert sources of Tavoliere mirror the Appenine and Gargano origin. During the Neolithic period, near the North-Eastern coast of the Gargano promontory (Apulia Region, Italy), an important network of mines represented the most ancient European example of systematic exploitation of primary chert sources. These high-quality raw materials were traded between prehistoric communities living on both sides of the Adriatic Sea. However, the Gargano promontory is not the only area of the Apulia Region with chert sources. Secondary sources of the Tavoliere plain deposits and primary sources of the Southern Apennines must be considered in addition to the Gargano chert-bearing limestones. This paper provides an overview of chert sources distribution in the Gargano and Tavoliere plain through a chert sources map based on up-to-date geological and archaeological information. The map represents the first lithic procurement mapping in the Region and it is a very useful tool for planning sampling activities and detect the potential chert sources exploited in Neolithic times. The map was used for sampling pebbles near the coast and inland of the investigated area. A non-destructive multi-parametric protocol for chert investigations (NM-PCI) method was applied to all the collected secondary samples. The results were compared at first with those of the Gargano mines. The output of the partition around medoids (PAM) procedure shows, as a general trend, that primary sources are well grouped, while secondary sources show less clear compositional fingerprints. However, the features of the coastal and inland pebbles are quite different. [ABSTRACT FROM AUTHOR]

Abstract The Caminada Headlands is a beach and dune system near Port Fourchon in coastal Louisiana that provides natural protection for back barrier marshes against storm surges and wave overtopping. Due to significant shoreline erosion and regional subsidence, a beach and dune restoration project was initiated in 2012 to replenish the shoreline front. Because of the underlying soft deltaic sediments, this restoration effort was expected to cause significant increase in the applied vertical stress and thus sediment settlement. To quantify the degree of settlement occurring within the compressive sediment layers and the fill, extensive geotechnical investigations were conducted for design and installation of settlement plates and subsurface settlement anchors to monitor the field performance. This paper presents the geological and geotechnical investigations, measured material properties, and corresponding empirical correlations developed from fifty-one (51) laboratory consolidation tests. The pre- and post-survey elevations of the site are also used to determine the change in vertical stress with depth at the instrumented sites. The measured material properties and vertical stress profiles can be used to calibrate the numerical modeling of the sediment and fill settlements. [ABSTRACT FROM AUTHOR]

Submerged Artificial Headland (SAH) and Detached Artificial Headland (DAH) are two types of modified artificial headland to provide better water exchange at slightly weakening beach protection effect compared to Traditional Artificial Headland (TAH). In this paper a numerical investigation is conducted on performances of SAH and DAH in a beach nourishment project. The beach protection and water exchange are considered respectively. A shoreline model and a constituent transport model are set up to simulate the post-project shoreline change and water exchange. The results of shoreline changed model show that both the SAH and DAH have good performance in protecting the beach behind them, while in SAH case the shoreline has a smoother shape. The effects of eroding and silting characteristics of the beach on the performance of SAH and DAH are also discussed. The SAH and DAH have similar performance of reducing the flushing time and improving the water exchange in the area behind the artificial headlands compared to TAH. The effect of tidal condition on the flushing time is also discussed. It is suggested that both SAH and DAH are feasible and effective measures to strengthen the water exchange at the cost of an acceptable loss of beach protection. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a comprehensive study of wave refraction, wave and wind driven sediment transport, foredune development and Holocene barrier evolution over a variety of time scales at Moçambique Beach, Santa Catarina State, Southern Brazil. The motivation for this study was to examine the relationships between estimated wave driven sediment transport, medium and long term aeolian transport, foredune development, and Holocene barrier volumes and morphology. An analysis of 2years of wave rider data for the region shows two well defined peaks of frequencies: one of swell waves from the south with a period of 12s, and another peak of sea waves from east-northeast with a period of 7s. Longshore sediment transport rates were calculated using high resolution hindcast wave data for the South Atlantic Ocean, which was calibrated by the measured buoy data. The dominant southerly waves drive a longshore gradient in wave energy from south to north, and nearshore/surf zone sediment transport increases from south to north. Beach grain size is fine in both the south and north, and medium in the center. The combination of grain size and wave energy variations creates a marked alongshore variation in surf zone beach types ranging from low energy dissipative in the south, moderate energy intermediate in the central area to moderate to high energy dissipative in the north. Estimates of aeolian sediment transport, volumetric changes in foredune deposition and total Holocene dunefield volumes were also calculated. Results indicate that the morphological behavior of the foredune profiles reflects the gradients of longshore sediment transport and the exposure to wind energy and aeolian sediment delivery, with a maximum of sediment volume and transport towards, and in the central part and northern end of the barrier. Holocene (0–7000years) barrier volumes vary along the embayment, mimicking the trends in both calculated wave and wind driven sediment transport. The Short and Hesp (1982) model was more suitable in predicting the long term (Holocene) barrier evolution than the size and volume of the foredune. The combination of wide beach, high energy dissipation, maximum sediment supply, and high exposure to strong onshore winds is found in the northern end of the embayment where Holocene subaerial barrier volumes are at a maximum. Overall, this study proves that foredune development is closely related to wind exposure, wave energy and gradients of longshore sediment transport, and that dunefield development reflects the increase downdrift in potential sediment supply from the southern to the northern end of the beach, and the change alongshore from low energy dissipative, through intermediate, to high energy dissipative beach-surf zone environments. This paper significantly extends previous models of beach and dune interactions in that it (i) actually determines wave driven sediment transport for various sections of a long embayment, (ii) relates those transport patterns to surf zone/beach morphodynamic types and variations in alongshore sediment patterns, and (iii) correlates foredune volumes and Holocene barrier volumes (which reflect proxy Holocene onshore transport rates) with wave driven sediment transport rates. [Copyright &y& Elsevier]

This paper presents a comprehensive study of headland bypassing around seven headlands with different orientations and degrees of wave and tide-induced current exposure, located on the northern shore of Santa Catarina island, southern Brazil. It encompasses an extensive dataset including detailed in situ measurements of bathymetry, beach profiles, sediment transport (traps), waves, currents and tides. The entrained sediment decreased in magnitude towards the more sheltered coast while maintaining comparable sediment grain distributions, supporting the hypothesis of a connection between beaches. Based on in situ measurements, a numerical model was calibrated (waves, currents and tides) and validated, with errors representing 11% of the magnitude of the measurements. Furthermore, three sediment transport formulae were tested to identify the one that best reproduced the processes at the study site. A model using tides, winds and full wave spectra as input was run to identify the general (net) trend of annual sediment transport in the study area aiming to identify if/where headland bypassing occurs. The results show that headland sand bypassing does occur in the study area confirming the anticlockwise sediment transport pathway. The present work highlights the role of sediment bypassing on embayed-headland bound beaches, which are usually considered to be closed cells. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents MEPBAY and SMC software tools that allow comprehending and solving problems in headland-bay beach through a parabolic model. These tools can be employed as coastal engineering design tools (including nourishment designs) and also for academic purposes. They are oriented to different end-users, including coastal technicians, scientists and undergraduates and as coastal engineering design tools, they can be applied to different operational levels (pre-design and design). The aim of the paper is to present design guidelines, the capabilities of the tools, their potential use and applications. Both tools were applied to analyze San Lorenzo Beach and demonstrate their ability at different project levels. [Copyright &y& Elsevier]

Abstract: Headland-bay beach (HBB) is one of the most prominent physiographic features on the oceanic margin of many countries in the world. Under the influence of a predominant swell, its curved periphery in natural environment may reach static equilibrium and remains stable without sediment supply from updrift and/or a riverain source within its own embayment. Coastal scientists and engineers have attempted to develop mathematical expressions to quantify this ideal bay shape since the 1940s. As the scenario with depleting sediment supply has become a common reality on many parts of the world coastline in more recent time, some coastal engineers have advocated a rational approach to mimicking the static bay shape found in nature in order to mitigate beach erosion as well as for coastal management. Nowadays, many useful applications have emerged since the publication of the parabolic bay shape equation (PBSE) developed for static equilibrium planform (SEP) in late 1980s. The advance in modern computer technologies and international collaboration has further facilitated the exchange of knowledge and applications of this static bay beach concept (SBBC). This paper reviews the progress on the research in HBB made by geographers and geologists since the 1940s, together with the involvement of coastal engineers working on shore protection and management from the 1960s. Aided by software MEPBAY developed in 2003 for the PBSE, several practical examples are demonstrated in this paper for the stability verification of natural and man-made bay beaches, shore protection, mitigating downdrift erosion of a harbour, design of recreational bay beach, as well as for environmental impact assessment. Limitations on and clarifications for engineering applications based on the SBBC are also discussed in this paper. [Copyright &y& Elsevier]

South Africa's southwestern Cape occupies a critical transition zone between Southern Hemisphere temperate (winter) and tropical (summer) moisture-bearing systems. In the recent geological past, it has been proposed that the relative influence of these systems may have changed substantially, but little reliable evidence regarding regional hydroclimates and rainfall seasonality exists to refine or substantiate the understanding of long-term dynamics. In this paper we present a mid-to late Holocene multi-proxy record of environmental change from a rock hyrax midden from Katbakkies Pass, located along the modern boundary between the winter and summer rainfall zones. Derived from stable carbon and nitrogen isotopes, fossil pollen and microcharcoal, these data provide a high resolution record of changes in humidity, and insight into changes in rainfall seasonality. Whereas previous work concluded that the site had generally experienced only subtle environmental change during the Holocene, our records indicate that significant, abrupt changes have occurred in the region over the last 7000 years. Contrary to expectations based on the site's location, these data indicate that the primary determinant of changes in humidity is summer rather than winter rainfall variability, and its influence on drought season intensity and/or length. These findings are consistent with independent records of upwelling along the southern and western coasts, which indicate that periods of increased humidity are related to increased tropical easterly flow. This substantially refines our understanding of the nature of temperate and tropical circulation system dynamics in SW Africa, and how changes in their relative dominance have impacted regional environments during the Holocene. [ABSTRACT FROM AUTHOR]

Abstract: The exceptionally high plant diversity in the Cape region of southern Africa continues to attract considerable attention. In a recent paper Linder et al. (2010) concluded that diversification has been promoted by the physical complexity of the Cape environment and by certain biotic interactions, such as those between bees and flowering plants. Although these authors acknowledge the potential role of seed dispersal by ants, they suggested that there were no tests which would demonstrate whether rates of diversification were higher in myrmecochorous lineages versus those with other biotic or abiotic dispersal mechanisms. Here we argue that a set of recent papers by Dunn et al. (2007) and Lengyel et al. (2009, 2010) provide compelling evidence that myrmecochory may have resulted in a doubling of plant diversification, largely due to the greater likelihood of genetic isolation and also of the increased survival rate of plants possessing this dispersal mode. Here, we suggest that myrmecochory, which may be favoured in low nutrient soils, could be a key contributor to the high floristic biodiversity in the Cape region, as well as in other old, climatically stable landscapes such as those of southwest Australia. [Copyright &y& Elsevier]

Abstract: The concept of equilibrium plan form and equilibrium profile has been widely used as an engineering tool in order to design beach nourishment projects. The scope of this paper is to further explore this “equilibrium beach” concept in crenulated bays, as a long-term tool for beach nourishment projects. The proposed methodology is based on and combines the static equilibrium plan and profile for long-term analysis. This methodology includes a modified equilibrium plan form, which is able to define the orientation of the local wave front in the diffracting point, and also to locate the downcoast starting point of the static equilibrium beach from which the parabolic plan form of is valid. This methodology permits the application of any equilibrium profile formulation. An example of the application of this methodology and long-term formulations to the design of the Spanish nourishment project of Poniente Beach (Gijón) is presented. Ten years after its construction, the beach has still got a static equilibrium and remains pretty close to the predicted equilibrium beach in plan and profile. [Copyright &y& Elsevier]

Abstract: This paper is devoted to the analysis of the hydrodynamic equilibrium of a headland or semi-elliptic shaped beach. It is shown that the state of equilibrium depends not only on the in- and outgoing sediment but also on the accommodation of the sediment within the embayment. The shape and relative depth of shoals, or settling zones, also directly affect the wave and current patterns inside the bay, within which the resultant breaker line almost stops wave-induced currents at some locations, whereas the magnitude of current increases at other locations. Several numerical tests are analytically conducted in a semi-elliptic beach with two symmetrical shoals of varying relative depth where circulatory current systems are detected and analyzed. Numerical modelling for wave climate and wave-induced current estimation is also presented in order to corroborate results and provide a tool for complicated and/or physical domains. The results lead to a redefinition of the concept of equilibrium for headland-bay beaches taking into account not only the net sediment transport but also the role of the formation and disappearance of settling zones, as well as sediment interchanges between the beach and shoals. [Copyright &y& Elsevier]

Abstract: This paper presents a case study on the modelling of a headland bay beach influenced by sediment input from migrating coastal dunes. The study area is the region around the town of Ingleses on Santa Catarina Island, Santa Catarina state, South-Eastern Brazil. Ingleses has been threatened by nature at two different fronts. At the north-eastern side of the town lies Ingleses Beach, a headland bay beach which seems to be subject to persistent erosion in recent years. On the south-western side the town is threatened by a migrating dunefield, which is encroaching onto houses and infrastructure, but which has not reached the beach in the past 70years. A second dunefield in the area does not pose a direct threat to the town, but passes it on the eastern side and forms an important influence on the development of the beach. The sediment influx rate from this dunefield to the beach is 10,000m3/year. To investigate the effect of the dunefields on the morphodynamic system, a numerical model has been created using the software packages SWAN and UNIBEST and the static equilibrium bay shape was determined by the software package MEPBAY. The result of the long-term scenario as predicted by UNIBEST agrees rather well with the static equilibrium bay shape found with MEPBAY. This provides sounds basis for the credibility of both models. Consequently, the predicted evolutional trend of the shoreline seems plausible. [Copyright &y& Elsevier]

Abstract: This paper presents a comprehensive review on the interaction between hydrodynamic processes, beach morphology and sedimentology at large scale coastal behaviour along the coastline of Santa Catarina, between Laguna and São Francisco Island, a microtidal east coast swell environment with headland and bay geomorphologies. The parabolic bay shape equation has proven to be a convenient and practical tool for studying the stability of the headland-bay beaches, tombolos, and salients in Santa Catarina. The beaches exhibit different patterns of sediment removal as a function of the degree of beach curvature. In highly curved beaches, there is a well-developed shadow zone and a range of morphodynamic conditions, from a sheltered low-energy beach adjacent to the downdrift headland to a high-energy exposed beach on the straight end of the headland-bay beach. The less curved beaches instead, tend to show more uniform behaviour since they are directly exposed to incident waves. There is no obvious relationship between average wave height and mean grain size, showing the importance of sediment source to characterize the sedimentary distribution patterns in the study area. The analysis of beaches showed that beach morphodynamics and sequence profiles for a bay–headland coast in a microtidal east coast environment is a function of geological inheritance (e.g., distance between headlands and orientation, nearshore and inner shelf morphology, coastal plain morphology, and sediment source), and hydrodynamic factors (wave conditions, oceanic wave exposure and relative tidal range). [Copyright &y& Elsevier]

Abstract: The Australian coast contains 10,685 beaches which occupy 49% of the 30,000km coast and average 1.37km in length. Their relatively short length is largely due to the presence of bedrock, calcarenite and laterite, which form boundaries to many of the beaches, as well as occurring as rocks, reefs and islands along and off the beaches. This geological inheritance plays a major role in Australian beach systems — determining their length and through wave refraction and attenuation influencing beach location, shape, type, morphodynamics and circulation, which in turn influence sediment transport and the backing dune and barrier systems. This paper uses a database covering every Australian beach to review the role of headlands, rocks and reefs on Australian beaches. Major effects are the short average beach length; reduction in breaker height resulting in lower energy beach types; wave refraction resulting in increased beach curvature; the presence of topographic rips on moderate and higher energy beaches and megarips during high wave conditions; and the interruption of and/or trapping of longshore sand transport leading to beach rotation. [Copyright &y& Elsevier]

The Palaeo-Agulhas Plain formed an important habitat exploited by Pleistocene hunter-gatherer populations during periods of lower sea level. This productive, grassy habitat would have supported numerous large-bodied ungulates accessible to a population of skilled hunters with the right hunting technology. It also provided a potentially rich location for plant food collection, and along its shores a coastline that moved with the rise and fall of sea levels. The rich archaeological and paleontological records of Pleistocene sites along the modern Cape south coast of South Africa, which would have overlooked the Palaeo-Agulhas Plain during Pleistocene times of lower sea level, provides a paleoarchive of this extinct ecosystem. In this paper, we present a first order illustration of the " palaeoscape modeling " approach advocated by Marean et al. (2015). We use a resourcescape model created from modern studies of habitat productivity without the Palaeo-Agulhas Plain. This is equivalent to predominant Holocene conditions before recent landscape modifications for farming. We then run an agent-based model of the human foraging system to investigate several research questions. Our agent-based approach uses the theoretical framework of optimal foraging theory to model human foraging decisions designed to optimize the net caloric gains within a complex landscape of spatially and temporally variable resources. We find that during the high sea-levels of MIS 5e (+5–6 m asl) and the Holocene, the absence of the Plain left a relatively poor food base supporting a much smaller population relying heavily on edible plant resources from the current Cape flora. Despite high species diversity of plants with edible storage organs, and marine invertebrates, encounter rates with highly profitable resources were low. We demonstrate that without the Palaeo-Agulhas Plain, human populations must have been small and low-density, and exploited plant, mammal, and marine resources with relatively low caloric returns. The exposure and contraction of the Palaeo-Agulhas Plain was likely the single biggest driver of behavioural change during periods of climate change through the Pleistocene and into the transition to the Holocene. • Agent-based model of Later Stone Age human foraging in coastal South Africa. • Reconstructed food resource landscape including mammals, shellfish, and plants. • Sustainable population is under 20 individuals/100 km^2. • Long foraging days (10 + hours per day) and small groups needed to survive. • Edible plants, including USOs, make up 80% or more of the diet. [ABSTRACT FROM AUTHOR]

Abstract: A comprehensive dataset of Synthetic Aperture Radar (SAR) images from the west Iberian coast is used to identify the Estremadura Promontory as an oceanic hotspot for internal solitary waves. The full two-dimensional structure and the main physical properties of these waves are revealed for the first time. Composite maps and a statistical analysis show that these waves have two main propagation paths coming from the northern and southern slopes of the promontory, and that on average they have horizontal scales of the order of 400m and crestlengths around 9km. The overall propagation of the internal solitary wave field observed in the SAR images is evaluated, using a proxy measure for energy based on observed wavelengths, crestlengths and radar backscatter intensities. A refraction pattern is found to divert the meridionally propagating waves to the east, where they eventually dissipate in the inner-shelf regions close to shore. The barotropic body force is calculated and the most likely generation locations are identified. It is found that there is more energy emanating from the south while the tidal forcing seems to be equally divided between both flanks of the promontory. Calculations using the vertical excursion inverse Froude number (defined by Legg and Klymak, 2008) indicate that this is probably related to the steeper slopes located in the northern side. This pronounced bathymetry is more likely to generate internal hydraulic jumps and overturning, which may inhibit the disintegration of the internal tide into solitary waves. [Copyright &y& Elsevier]

Presents a study which evaluated the transfer of surface water signals into the geological record based on a 4-year sediment trap record of alkenones from the filamentous upwelling region off Cape Blanc in north west Africa. Materials and methods; Results; Discussion and conclusions.

Presents information on a study of live benthic foraminifera along a transect across the main area of organic matter deposition in the Cape Blanc upwelling region. Study area, material and methods; Results and discussion.

Proposes a new nonlinear mechanism for the generation of `meddies' by a cape. Creation of meddies by the Cape of St. Vincent which forces the Mediterranean outflow to turn back on itself; Process of traditional generation mechanism associated with separation, frontal instability and unsteady outflows or geostrophic adjustment.