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This paper presents a reconstruction of the Holocene evolution of the Inskip Peninsula in SE Queensland. The peninsula links two major dune fields, the Cooloola Sand Mass to the south and K'gari (Fraser Island) to the north. Geomorphic features of this peninsula include remnant parabolic dunes, numerous beach ridges with foredunes, and a series of spits. Together these features provide insight into Holocene coastal evolution and changing marine conditions. A remnant beach ridge/foredune complex at the northern portion of Inskip may have been connected to K'gari and a river/tidal channel near Rainbow Beach township which separated it from the Cooloola Sand Mass to the south. This channel avulsed northward in the early mid-Holocene (after 8.8 ka) with spit development from the south. This was followed by a phase of beach-ridge/foredune complex development that started by ~6.7 ka. Stratigraphic evidence from the highest and best developed parabolic dunes in the northern portion of Inskip Peninsula indicates dune development from the mid-Holocene beach complex by 4.8 ka. Beach ridges with foredunes continued to prograde but notably declined in size during the late-Holocene. In the latest Holocene (<4.8 ka) many of the late-Holocene beach ridges/foredune complexes have been truncated by a re-orientation of the shoreline and longshore sediment transport has promoted the growth of the modern spit at the northern end of the peninsula. Erosive and longshore processes continue to be highly active because of tidal interactions between Great Sandy Strait and the Coral Sea. This detailed study of Inskip Peninsula's evolution aids significantly in future coastal management decisions, and provides evidence for World Heritage Area extension for the Cooloola Sand Mass, including the incorporation of Inskip Peninsula itself. It also contributes to the global understanding to coastal evolution in an area of strong wave and tidal interaction. [ABSTRACT FROM AUTHOR]

Holocene coastal evolution has been extensively studied by workers from various earth science disciplines, particularly sedimentologists and geomorphologists. Some of these studies have focused on the history of regional sea-level changes in various ocean basins and the mechanisms – such as eustasy, glacio-isostasy, sediment compaction, neotectonics and climatic forces – involved in such changes. Although beach ridges have been used to identify steps in coastal evolution, only in a few cases have beach ridge systems been investigated with respect to event histories (for example, cyclones and tsunamis). Beach ridge systems, however, belong to the most promising geo-archives for the study of climate change and sea-level variations over the Holocene, as well as for deciphering event histories. This paper presents examples of some studies in this field, in relation to a global overview of beach ridge systems and their morphological characteristics. [ABSTRACT FROM AUTHOR]

The primary aim of this paper is to describe and discuss the palaeoclimatic significance of mid- to late-Holocene fields of raised-beach ridges at Matalaniemi and sea-ice-pushed boulders at Kutovaya Bay on the Kola Peninsula. These beach features are interpreted as indicating at least 12 periods of stormy conditions alternating with calmer periods of relatively low sea-surface temperature since about 8000 cal. BP. A consistent chronology of climate change is difficult to establish due to considerable uncertainties attributed to local beach processes and relative sea-level displacements. A tentative interpolated chronology is suggested. At present, terrace formation at Matalaniemi and the absence of sea ice at Kutovaya Bay indicate an intermediate windy and mild type of winter climate. [ABSTRACT FROM AUTHOR]

Seismic and core data off the Tagliamento river delta, northern Adriatic Sea, Italy, have allowed the recognition of a partially eroded sand ridge at 12 to 18 m water depth, which has been interpreted as a submerged wave-dominated delta with associated beach-ridge complexes. The ridge shows local channel fill features, interpreted as the result of the filling of tidal channels connecting the open sea with bays and lagoons placed adjacent to the ancient delta. This interpretation resembles the present day setting of the Tagliamento delta, located landwards. It is inferred that the recognized delta was drowned during the latest stage of the post-glacial sea-level rise, when the shoreline shifted near the present day position. New studies are needed to recognize other submerged deltas and barrier islands, which may allow the reconstruction of the post-glacial sea-level rise in the Mediterranean and of the position of ancient paleoshorelines. [ABSTRACT FROM AUTHOR]

Stratigraphic, morphologic and radiocarbon data from Puerto Deseado coastal area (Santa Cruz Province, Argentina) indicate that the Holocene coastline formed in response to the discontinuous aggradation of coarse gravely beaches since c. 6300 cal. yr BP related to a progressive falling of relative sea level. Beach ridge crests crudely approximate to the sea level showing at least three steps of aggradation and relative sea-level lowering. Two inactive abrasive notches at c. 7.9 and 3.4 m a.s.l. have recorded this sea-level trend, suggesting two important phases when sea level was stationary. This allows the estimation of a rate of relative sea-level fall in the last c. 3500 years of c. 1.8 mm/yr. Moreover, notches and morphological data indicate that the crest of the beach ridges exceeded the sea-level height by c. 2 ± 0.5 m. This value provides a reasonable regional estimate to be applied to produce comparable relative sea-level curve for Atlantic Patagonia coast. [ABSTRACT FROM AUTHOR]

Geological studies of past and present sea level rely on valid and robust features marking sea level in geological sections. Present sea-level markers around the upper shoreface to beachface transition are detected in a beach-ridge plain formed in a microtidal regime. These sea-level markers identify specific relative sea levels at the time of formation. Ground-penetrating radar (GPR) data collected across the youngest part of the beach-ridge system of Feddet, Denmark are compared with independent coastal morphological and sedimentological data of the active strand plain and interpreted in relation to sea-level data. The data show consistency between dip values of the present beachface and upper shoreface compared with dip values of interpreted beachface and upper shoreface GPR reflections. A clear change in dip value is observed between beachface and upper shoreface deposits in both data sets. Within few centimetres, this break point coincides with actual sea level and is interpreted to correspond to downlap points observed in the GPR reflection data. Furthermore, our observations may indicate that downlap points of deposits, formed under both relatively high and low water levels, are preserved and may be identified in GPR reflection data. Downlap points identified in GPR data across microtidal beach-ridge systems from other localities can also constitute markers of palaeo-sea level at the time of deposition. Records of these sea-level markers can be used to reconstruct the local relative sea-level history during the Holocene. [ABSTRACT FROM AUTHOR]

For the Malay-Thai Peninsula several sea-level curves for the younger Holocene, based on field evidence as well as on hydro-isostatic modelling of a far-field site, have been published. The general assumption is a rapid rise to a mid-Holocene maximum up to +5 m above present sea level, followed by a constant or oscillating regression. However, from the Andaman Sea coast of Thailand, which was affected by the 2004 tsunami, only isolated observations are available regarding Holocene sea levels. Thus, the timing and magnitude of the Holocene highstand as well as the course of the regression remain to be defined. As several palaeotsunamis could be detected in the meantime it is important to know the related sea levels as exactly as possible to judge the energy, inundation width and potential wave height of these events. Therefore, fixed biological indicators from the rocky coasts of the Phang-nga Bay and Phuket, as well as morphological indicators from beach-ridge and swale sequences along the exposed west coast (Ko Phra Thong) were studied, to gain information about the Holocene sea-level development in this region. While oyster and coral data from the Phang-nga Bay and Phuket document a Holocene maximum of +2.6 m at 5700 cal. BP, the ridge crests and swale bases in the northwest of the study area point to maximum heights of +1.5–2.0 m above the present level around 5300 years ago. During the last 3000 years, to when the largest part of the Holocene palaeotsunami deposits from Thailand was dated, relative sea levels (RSL) in both areas did not exceed +1.5 m. [ABSTRACT FROM PUBLISHER]

The Sahara Desert is the most extensive desert on Earth but during the Holocene it was home to some of the largest freshwater lakes on Earth; of these, palaeolake Megachad was the biggest. Landsat TM images and Shuttle Radar Topography Mission (SRTM) digital topographic data reveal numerous shorelines around palaeolake Megachad. At its peak sometime before 7000 years ago the lake was over 173 m deep with an area of at least 400 000 km2, bigger than the Caspian Sea, the biggest lake on Earth today. The morphology of the shorelines indicates two dominant winds, one northeasterly that is consistent with the present-day winds in the region. The other originated from the southwest. We attribute it to an enhanced monsoon caused by a precessionally driven increase in Northern Hemisphere insolation. Subsequent desiccation of the palaeolake is recorded by numerous regressive shorelines in the Sahara Desert. [ABSTRACT FROM AUTHOR]

Geometric and cross-cutting relationships between the Wilson Piedmont Glacier and raised beach ridges indicate that the glacier margin has undergone Holocene fluctuations. During mid-Holocene time, the Wilson Piedmont Glacier retreated to a position less extensive than at present. A subsequent readvance culminated less than 250 years ago. Since AD 1956, the glacier and adjacent large snow ramps have retreated up to 600 m in some locations. Large snowbanks have also disappeared. Although the cross-cutting relationships and chronology indicate a late-Holocene advance at approximately the same time as the 'Little Ice Age' event, the magnitude and style of that advance differ from those of the classic 'Little Ice Age' glacier fluctuations in the Northern Hemisphere. [ABSTRACT FROM AUTHOR]

The low-energy beach ridge system near the town of Jerup, in the extreme north of Denmark, was sampled at 154 sites, on a pattern of one per ridge (intervals of 50-51 years, starting about 7800 BP). None of these ridges was built by storm waves or by wind. They are not like high-energy ridges to the north, which differ in size, morphology, bedding and granulometry.In the low-energy system, sand grain-size kurtosis (inverted) is a reliable index of wave energy density in the surf zone, and also indicates an important component of settling. Kurtosis tends to be more-or-less constant in sets of 5-20 ridges, then to change abruptly at set boundaries, which therefore represent sea- level changes (1-5 m), centuries apart. The sixth moment measure (grain size) and ridge spacing also indicate sea-level change. Glacio-isostatic rebound has averaged 2 to 2.1 mm yr-1 for this system; the history of this rebound plots best on a semi-log diagram showing a decrease from about 4 mm yr-1 (at 6000 BP) to about 1.3 mm yr-1 (at 1000 BP).The Jerup sea-level curve matches the Gulf of Mexico curve as far back as the latter goes. Each provides sea level history in the 'Little Ice Age' (most recent millennium), and other changes since 3000 BP; the Jerup curve shows earlier fluctuations. The largest changes were in the range 3-5 m; maximum rates were about 1 cm yr-1 . [ABSTRACT FROM PUBLISHER]

Grain-size kurtosis of sand in the beach ridge plain of St. Vincent Island, Florida, is numerically reasonably uniform within any one ridge set, but changes at important set boundaries. Where these changes are found, there are also differences in air photo and field appearance and in measured ridge-set heights. Sets with low kurtosis (∼3.0) stand topographically high, and sets with higher values (∼3.6) stand low. Study of wave energy levels and beach sand grain-size kurtosis along modem Gulf of Mexico beaches shows that kurtosis is an inverse function of surf-zone energy density.Storms and storminess (for the study area) can be evaluated in the framework of the selective- transport model of May (1973); the actual data sequence is greatly different from what is required by the model, and therefore storms and storminess cannot be invoked to explain the history of the area. Instead, the data sequence matches results predicted by the model for small sea-level changes. Storms and tectonism do not have appropriate durations and rates of operation, hence did not cause changes in kurtosis across St. Vincent Island. Slow land elevation changes (warping, isostatic adjustment) do not take place repeatedly up and down like the granulometric parameters. Tidal effects, in the study area, are both much too small and too frequent to have been important.The changes in kurtosis therefore indicate water level changes, and provide a sea-level history, including three sea level drops and four rises, of 1-3 m each, since about 3000 BP. Similar results have been obtained elsewhere, so these results are not local. [ABSTRACT FROM PUBLISHER]