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Helm, C.W.; Cawthra, H.C.; De Vynck, J.C.; Dixon, M., and Stear, W., 2021. Elephant tracks: A biogenic cause of potholes in Pleistocene South African coastal rocks. Journal of Coastal Research, 37(1), 59–74. Coconut Creek (Florida), ISSN 0749-0208. The Cape south coast of South Africa contains extensive outcrops of Pleistocene aeolianite and cemented foreshore deposits. More than 250 vertebrate tracksites have been identified in these deposits, including 35 elephant tracksites. In places, where large palaeosurfaces are occasionally exposed, numerous potholes are evident on the remains of what is most likely a palaeo-coastline. Features suggestive of elephant tracks are apparent on such surfaces and in overlying layers. In order to develop, potholes require a disturbance or depression in the surface to act as a "pothole-precursor" on which erosive forces can act. While elephant tracks or similar biogenic origins for potholes have not previously been described, such an explanation appears plausible for at least some pothole features in areas known to have harboured elephants or other large vertebrate trackmakers when these surfaces were composed of unconsolidated sand. Four sites on the Cape south coast are examined and described. Evidence for use of beaches as travel corridors for elephants is described, and candidate Pleistocene trackmaker species are considered. The age of these palaeo-surfaces is considered to range from Marine Isotope Stage 11 to Marine Isotope Stage 5. It is concluded that depressions formed by elephant tracks should be considered as a precursor for the formation of potholes on suitable Pleistocene surfaces in littoral zones. [ABSTRACT FROM AUTHOR]

Ab Razak, M.S., Dastgheib, A., Suryadi, F.X., Roelvink, D. 2014. Headland structural impacts on surf zone current circulation, Proceedings 13th International Coastal Symposium (Durban, South Africa), Journal of Coastal Research, Special Issue No. 70, pp. 065-071, ISSN 0749-0208. The paper presents the morphodynamic investigation of embayed beaches through the impact of structural headlands. An XBeach model was successfully applied to predict the surf zone current pattern and to predict morphological features of three different embayment scales for low-moderate-high wave energy events. The formation of central rip currents in embayed beaches is linked to the presence of a sand bar, while topographical headland rips developed adjacent to the headland boundary are caused by the geological control of the headland structure itself. The effect of moderate and high waves has resulted to a decreased number of central rips in a longer embayment thus limiting the beach circulation to the cellular type. This type of rips could provide an initial insight into the offshore transport of sand from the coast. Whether wave breaking occurs outside or inside the embayment determines the initiation of large scale rip currents, megarips. Several factors that lead to the generation of megarip currents in literature should be taken into account as a guideline for morphodynamic studies in a high energy embayed coast. Nevertheless, the characteristics of surf zone current circulation in all cases presented in this study complies with the description of the theoretical embayment scaling parameter (δ') (Short and Masselink, 1999 and Castelle and Coco, 2012). Further establishment of this parameter is needed to properly describe the surf zone current circulation in embayed beach systems. [ABSTRACT FROM AUTHOR]

A personal narrative is presented which explores the author's experience of helping in conducting bathymetric surveys in Italy, along with a group of professionals who had worked at the Hydrographic Institute of the Italian Navy.

ABSTRACT Ab Razak, M.S.; Suryadi, F.X.; Jamaluddin, N., and Mohd Noor, N.A.Z., 2018. Shoreline Planform Stability of Embayed Beaches Along the Malaysian Peninsular Coast. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 631–635. Coconut Creek (Florida), ISSN 0749-0208. The existence of embayed beaches is pronounced along the coast of Peninsular Malaysia. The stability of such beaches is yet to be confirmed. The present study aims at investigating the shoreline planform stability on the east and west coasts of Peninsular Malaysia. 190 embayed beaches were found along the Malaysian Peninsular coast, including natural beaches and man-made beaches. Of these, 139 beaches were on the west coast while 51 beaches were on the east coast. Results of the MEPBAY model show along the east coast, 45%, 51% and 4% were classified as the static, dynamic, and natural beach reshaping, respectively. Beaches on the west Peninsular coast that is mainly characterised by the muddy coast were more pronounced to be in the static state which comprised of 85% compared to the beaches on the east coast, that are mostly sandy. While, another 15 % were fall under dynamic equilibrium state. Sediment supply from the river, improper placement of coastal structures, sediment bypassing at headland are some possible factors that may cause the dynamic and instability of the embayed beaches studied. [ABSTRACT FROM AUTHOR]

The equatorial coast of NE Brazil consists of long and wide sandy beaches, segmented by rhythmic headlands, sometimes with seacliffs. Large and extensive mobile transgressive dunefields distribute up to 6 km landward of the coastline. The coastal area of Ceará state, as examined in this study by the means of measurements, field work, and remote sensing, illustrates a characteristic morphology composed of interactive headland, beach, and dune systems. Under persistent unidirectional wind and wave forcing, the morphodynamics of the studied coast is strongly controlled by the headlands because they produce an interruption of the longshore sand transport at their contact, resulting in accretion updrift of the headland and in erosion downdrift of the headland. The headland bypass dunefield activates one major mechanism and dynamics of the system headland-beach-dune because they refeed the beaches in the process of erosion downdrift. Littoral bypass is also an important process, supplying the cell with new sand, together with the erosion that takes place in the zetaform beach. Such a unique system can be strongly affected by anthropogenic activities, which can influence nearly all the factors at all temporal and spatial scales. [ABSTRACT FROM AUTHOR]

Huguet, J.-R.; Castelle, B.; Marieu, V.; Morichon, D., and de Santiago, I., 2016. Shoreline-sandbar dynamics at a high-energy embayed and structurally-engineered sandy beach: Anglet, SW France. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 393-397. Coconut Creek (Florida), ISSN 0749-0208. Anglet beach, Basque Coast (SW France), is a 4-km long embayment bounded by a prominent headland in the South and by the southern Adour River training wall in the North. The beach is structurally-engineered with, within the embayment, 6 groins and 3 distinct sectors where the beach is backed by a seawall. The beach is high-energy intermediate, mostly double-barred, composed of medium to coarse sand with a steep beach face (∼1/10). In January 2013, a video system was installed at the Southern end of Anglet beach at about 70 m above mean sea level to monitor about 2 km of the southern beach of Anglet that includes 4 groins extending about 100 m seaward and a 1-km seawall backing the beach. The study period includes the winter 2013/2014 that was outstanding in terms of the available energy arriving at the coast with a 2-month-averaged significant wave height peaking at 3.6 m. Despite the extreme storm wave conditions during the winter 2013/2014, the outer bar crescentic patterns maintained and even further developed. The beach eroded by O(10 m) and, surprisingly and in contrast with the nearby northern open beaches, they recovered to their pre-winter 2013/2014 state within only a few months. Overall, Anglet beach appears to respond predominantly at individual storm frequency rather than at seasonal timescales, with the groins and headland acting as major controlling boundaries influencing beach state and dictating rip channel locations. [ABSTRACT FROM AUTHOR]

Thomas, T.; Rangel-Buitrago, N.; Phillips, M.R.; Anfuso, G.; Williams, A.T.. and Oakley, J.A.. 2016. Subaerial rotation on an open coast beach: PendineWest Wales, UK. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 482-486. Coconut Creek (Florida), ISSN 0749-0208. Beach profiles and storm related forcing agents were used to assess subaerial beach rotation on an open coast macro-tidal beach. Analysis highlighted a negative phase relationship existed between the beach extremities and variation between negative/positive correlations within the central region identified that medium timescale open coast beach rotation existed. Cross-correlation showed timelag variations in subaerial volume exchange between adjacent sectors lagged behind one another by up to 18 months. While, annually averaged storm climate results highlighted a reduced temporal trend in terms of occurrence, intensity and power. Qualitatively, links were established between storms and erosive/accretive variations in the MHW shoreline indicator that suggest that these events influence beach rotation. Storm wave direction was established to be an important factor and it was concluded that the 3 river estuary complex acted as a surrogate headland restricting sediment by-pass, essentially forming an almost closed cell. These results should be tested at other open coast sites. [ABSTRACT FROM AUTHOR]

FitzGerald, D.M., Georgiou, I., and Kulp, M., 2016. Restortation of the Chandeleur Barrier arc. Louisiana. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 1282 - 1286. Coconut Creek (Florida), ISSN 0749-0208. The north-south trending barrier arc of the Chandeleur Islands protects valuable wetlands and reduces hurricane impacts in southeastern Louisiana. Avulsion of the lower Mississippi River ~ 1500 ka led to reworking of the St. Bernard deltaic headland concentrating sand and producing the proto-Chandeleur Islands. During the same period, landward interior delta plain erosion and subsidence formed Chandeleur Sound. Since the 1980's, isolation from new sand sources, high rates of relative sea-level rise (5 mm/yr), and hurricane impacts have produced a low transgressive barrier, periodically breached by numerous hurricane passes. Much of the sand eroded during storms is transported laterally to the ends of the barrier arc and lost from the system. A sustainable restoration plan for the barrier chain involves massive sand nourishment (from Hewes Point and St Bernard shoals ~ 285 × 106 m3) while accommodating its natural landward migration. Sand would be placed along existing barrier segments to build beaches and foredune ridges. Additional sand would widen and elevate recurved spits at hurricane passes. Sand would also be pumped behind the barriers to create a broad intertidal and subtidal sand sheet would provide a platform for barrier migration during transgression. Foredune ridges, recurved spits, and intertidal rear platforms would be vegetated to help stabilize these sand deposits and provide integrity. Finally, 15 large subtidal troughs would be excavated perpendicular and landward of the barrier arc, each filled with a 106 m3 of sand. This plan emphasizes landward sand transport during storms and gradual reintroduction of sand during transgression. [ABSTRACT FROM AUTHOR]

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Dillenburg, S.R.; Barboza, E.G.; Rosa, M.L.C.C.; Caron, F., and Bitencourt, V.B., 2020. Changes in the littoral drift of the Uruguayan coast during the Holocene and its influence in the continuing erosion in southern Brazil. In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 453–457. Coconut Creek (Florida), ISSN 0749-0208. In northern Uruguay and southern Brazil, a littoral drift system dominates from southwest to northeast. This littoral drift is a consequence of higher wave-energy, generated in southern latitudes and that has been operating on a long-term scale, playing an important role not only in the evolution of coastal barriers of this region during the Holocene but also in coastal erosion that presently occurs in some parts of this coast. From La Coronilla to Cabo Santa Marta, which is a coastal sector 750 km - along the coast is gently undulating, showing gentle projections located to the south of gentle reentrances, that are dominated by transgressive/stationary and regressive barriers, respectively. In general, the regressive barriers have been developed by sediments brought into the reentrances by long-shore currents. The main source of these sediments had been the transgressive/stationary barriers that occur along the coastal projections. This differentiation of barrier behavior started at around 6-5 ka, at the end of the Postglacial Marine Transgression (PMT), when all rivers were drowned, finishing the delivery of new coarse sediments to the coast. Also, at this time the large rock promontories of the Uruguayan coast were formed and started to retain sediments of the littoral drift system, triggering a long-term coastal erosion in the southernmost coastal projection. Regarding erosion that is occurring in this stretch of coast the important issue to be considered in future coastal planning is that erosion will continue to operate in the long-term but will also be (and certainly has been already) amplified by sea-level rise in the next centuries as projected by the Intergovernmental Panel on Climate Change (IPCC). [ABSTRACT FROM AUTHOR]

A photographic image of the Long Reef headland on the coast of Sydney, Australia is presented.