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Global inventories of stable sea-level markers for the peak of the last interglacial period, Marine Isotopic Stage (MIS) 5e, play a pivotal role in determining sea-level changes and in testing models of glacial isostatic adjustment. Here, we present surveying and radiometric dating results for emergent terraces from northern Madagascar, which is generally regarded as a stable equatorial site. Fossil coral specimens were dated using conventional and open-system corrected uranium series methods. Elevation of the upper (undated) terrace decreases from 33.8 m to 29.5 m over a distance of 35 km. An intermediate terrace has an average radiometric age of 130.7 ± 13.2 ka (i.e. MIS 5e). Its elevation decreases from 9.3 m to 2.8 m over a distance of 80 km. The record of the lowest terrace is fragmentary and consists of beach rock containing rare corals with ages of 1.6–3.8 ka. The spatial gradient of the MIS 5e marker is inconsistent with glacio-isostatic adjustment calculations. Instead, we propose that variable elevations of this marker around Madagascar, and possibly throughout the Indian Ocean, at least partly reflect spatial patterns of dynamic topography generated by sub-plate mantle convection. • Flight of three coral reef terraces in northern Madagascar correspond to Holocene, last and previous interglacial periods. • Upper terrace tilted from 33.8 m to 29.5 m over 35 km. Intermediate terrace tilted from 9.3 m to 2.8 m over 80 km. • Tilting cannot be generated by glacial isostatic adjustment alone. • Tilting likely to be generated in part by growth of a sub-plate thermal anomaly within the asthenosphere. [ABSTRACT FROM AUTHOR]

Yorke Peninsula in southern Australia is an important region for reconstructing relative sea-level histories due to its location on the eastern margin of the tectonically stable Gawler Craton and in one of the world's geographically most remote far-field locations from the Pleistocene ice sheets. Richly fossiliferous, skeletal carbonate sands of the last interglacial (125 ka) Glanville Formation crop out in the coastal cliffs along large sectors of southern Yorke Peninsula. Sedimentary facies include deepening-upward intertidal to shallow subtidal facies, relict storm beach facies and cobble and boulder beach deposits in more exposed, higher energy locations. During deposition of the Glanville Formation, southern Yorke Peninsula had a different coastal geography with two prominent marine corridors extending across the southern-most portion of the entire peninsula. In a 3 km long coastal cliff section in southern Hardwicke Bay, the Glanville Formation crops out as an upward-deepening intertidal-subtidal succession capped by supratidal and subaerially-exposed sediments with pervasive calcrete development. The sedimentary succession passes upwards from a basal unit of intertidal sand flat facies with abundant gastropods ( Batillaria diemenensis ) near the upper bounding (disconformity) surface, upwards into richly fossiliferous shelly sands (coquina) representing a shallow subtidal facies formed by sediment aggradation in response to a relative sea-level rise. The subtidal facies is dominated by the bivalve molluscs Katelysia sp. and Amesodesma angusta, signifying a water deepening event. The subtidal facies is in turn overlain by pedogenically modified skeletal carbonate sands with pervasive calcrete development signifying a relative sea level fall at the end of the Last Interglacial Maximum. The upper-bounding surface of the shallow-water subtidal facies ranges from 2.4 to 3.0 m Australian Height Datum (AHD) and by analogy with modern sedimentary environments suggests a maximum palaeo-sea level of 4.8 ± 1.0 m during the Last Interglacial Maximum. Uranium-series ages of 127.3 ± 2.1 to 115.0 ± 5.4 ka on specimens of the solitary coral Plesiastrea versipora from the subtidal facies confirm that the succession was deposited during the Last Interglacial Maximum, and are consistent with the independent stratigraphical evidence that the highstand event was represented by a single phase of relative sea-level rise. Correlation with other occurrences of the Glanville Formation in southern Australia has also been confirmed by aminostratigraphy. [ABSTRACT FROM AUTHOR]

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Paleo relative sea-level (RSL) indicators formed during the Marine Isotope Stage (MIS) 5e have been reported by a large number of studies worldwide. Despite this, three main aspects are seldom reported: (1) use of high-precision survey techniques applied to MIS 5e RSL indicators; (2) application of modern analogs to understand the indicative meaning of MIS 5e RSL indicators; (3) estimates of the effects of glacial isostatic adjustment (GIA) on the MIS 5e records. In this study, we show how the three points above have been addressed in a focused study on Last Interglacial outcrops on the island of Mallorca. We measured the elevation of several RSL indicators with high-accuracy differential GPS (vertical accuracies down to 0.1 m) and we established the relationship between each RSL indicator and the paleo sea level through calculation of the indicative meaning for each RSL indicator. In particular, we present a novel technique to calculate the indicative meaning of fossil beach deposits with a phase-averaged morphodynamic model (CSHORE). We show how this approach helps overcoming difficulties with the survey of the modern analogs for these indicators. Our results show that two paleo RSLs are imprinted in Mallorca at + 2.9 ± 0.8 m and + 11.3 ± 1.0 m. We then compare our field-based results with modelled paleo RSL, calculated from the predictions of the ice-earth coupled ANICE-SELEN model, using few different ice-sheet melting scenarios during MIS 5e. We conclude that indicative ranges can be derived from relatively simple morphodynamic models and that the comparison of field-derived and modelled RSL values is a good method to validate possible scenarios of MIS 5e sea-level variability, especially in absence of precise dating. [ABSTRACT FROM AUTHOR]

The Last Interglacial (MIS 5e, 128–116 ka) is among the most studied past periods in Earth's history. The climate at that time was warmer than today, primarily due to different orbital conditions, with smaller ice sheets and higher sea-level. Field evidence for MIS 5e sea-level was reported from thousands of sites, but often paleo shorelines were measured with low-accuracy techniques and, in some cases, there are contrasting interpretations about paleo sea-level reconstructions. For this reason, large uncertainties still surround both the maximum sea-level attained as well as the pattern of sea-level change throughout MIS 5e. Such uncertainties are exacerbated by the lack of a uniform approach to measuring and interpreting the geological evidence of paleo sea-levels. In this review, we discuss the characteristics of MIS 5e field observations, and we set the basis for a standardized approach to MIS 5e paleo sea-level reconstructions, that is already successfully applied in Holocene sea-level research. Application of the standard definitions and methodologies described in this paper will enhance our ability to compare data from different research groups and different areas, in order to gain deeper insights into MIS 5e sea-level changes. Improving estimates of Last Interglacial sea-level is, in turn, a key to understanding the behavior of ice sheets in a warmer world. [ABSTRACT FROM AUTHOR]

Late Pleistocene raised coral reef terraces form extensive outcrops up to 5 km wide along the Saudi coast. Porites coral were dated using U/Th while clastic sediment from Jeddah was dated using thermoluminescence. The pooled mean age for the coral samples is 121.5 ± 0.2 ka suggesting MIS 5e, even for the uplifted 16–20 m high terrace in the north at Haql. In Jeddah the MIS 5e back-reef succession is overlain by fluvial sediment that gave a TL age of 66 ± 13 ka. The structure and faunal composition of the coral terraces suggests that they accumulated in broad shallow embayments following the last interglacial transgression. The consistent elevation of these terraces suggests that the central and southern Saudi coast has been tectonically stable for at least the past 125,000 years and the coral reef terraces (at 3.5–5.5 m elevation) are consistent with the MIS 5e sea level high-stand that peaked at 6–9 m above present sea level. The Saudi coastal coral terrace north of Duba shows progressive uplift to 16–20 m near Haql since 108–120 ka as a result of ongoing transform faulting in the Gulf of Aqaba. [ABSTRACT FROM AUTHOR]

The upper successions of the raised reefal limestone of Jeddah coastal plain, especially at Obhur area, were investigated through three temporary exposed geologic sections such as south and northeast Obhur and Al Salam Street. Uranium-series age datings of these successions indicated that their topmost parts were mostly deposited during the last interglacial marine isotope stage 5e (MIS 5e). Lithological-faunal analyses and field observations allowed the division of these successions into two distinct layers: white limestone (lower) and brown shell-rich calcareous clay (upper). The lower layer is enriched with in situ coral boulders of Porites sp. and faviids, as well as with the foraminifers Amphistegina sp., indicating deposition near fore reef and reef crest environments. The upper layer is enriched with molluscs, echinoids, branched (and dwarfed faviids) corals, and the foraminifers Elphidium striatopunctatum and Challengerella bradyi, indicating deposition in back reef, lagoonal environments. The boundary between these two layers is very sharp and irregular, suggesting that the transition from the fore reef to lagoonal conditions was very rapid and catastrophe on coral reef ecosystem due likely to sea-level changes accompanied with warming and increased water runoff. The upper surface of the shell-rich calcareous layer seems to be truncated, but its microfossils could indicate that it was deposited when the sea level was higher than the present mean sea level (MSL) by at least 7 m. [ABSTRACT FROM AUTHOR]

Global sea level during the Last Interglacial (LIG, Marine Isotope Sub-stage 5e) peaked between c. 5.5 and 9 m above present, implying significant melt from Greenland and Antarctica. Relative sea level (RSL) observations from several far- and intermediate-field sites suggest abrupt fluctuations or jumps in RSL during the LIG highstand that require one or more episodes of ice-sheet collapse and regrowth. Such events should be manifest as unique sea-level fingerprints, recorded in far-, intermediate- and near-field sites depending on the source(s) of ice-mass change involved. To date, though, no coherent evidence of such fluctuations has been reported from near-field RSL studies in northwest Europe. This is an important problem because RSL fluctuations during the LIG are portrayed as warning signs for how polar ice sheets may behave in a future, warmer than present, world. Here we review the evidence for RSL change during the LIG using stratigraphic data from the best resolved highstand records that exist in the near-field of northwest Europe, from a range of settings that include lagoonal, shallow marine, tidal flat, salt marsh and brackish-water fluviatile environments. Consideration of previously published stratigraphic records from two sites in the Eemian coastal-marine embayment that existed in the central Netherlands, yields no clear indications for abrupt RSL change during the attainment of the near-field highstand. Nor do we find any such indications common to other records from countries bordering the North Sea, the Baltic Sea and the White Sea. Two modelling experiments that explore the global signal of hypothetical sea-level oscillations caused by partial collapse and regrowth of either the Greenland or Antarctic LIG ice-sheet, show that the North Sea region is relatively insensitive to mass changes sourced from Greenland but should clearly register events with an Antarctic origin, especially those that occur late in the LIG. The lack of evidence for abrupt sea-level fluctuations at this time in northwest Europe concurs with a lack of clear near-field evidence for ice sheet collapse. [ABSTRACT FROM AUTHOR]

Multidisciplinary analysis including paleomagnetic, sedimentologic, sea-level change, luminescence dating and palynologic research was performed on a 25 m long orientated core taken at Rutten, close to Eemian key localities in the Netherlands. The main goal of our research was to test a possible delayed onset of temperate conditions in this region compared to Southern Europe, occurring within the Last Interglacial. The sediments revealed the presence of the paleomagnetic Blake Event in ca. 10 m of lower-deltaic floodbasin sediments that contain a pollen record covering the Eemian. The position of the Blake Event in relation to the pollen stratigraphy concurs with the earlier studied Neumark Nord 2 site. Paleomagnetic correlation to core MD95-2042 off SW Iberia indicates ca. 5 kyr diachroneity between the pollen-based onset of temperate interglacial conditions between northern and southern Europe. The onset of the Eemian in north-western and central Europe (ca. 121.0 ka) post-dates the Marine Isotope Stage 6/5e transition by ca. 10 kyr. In addition, the Rutten data provide evidence for a relatively long duration of the Blake Event of at least 8 kyr. The late onset of the temperate conditions that define the base of the Eemian, imply that NW Europe with the Eemian type area is not the most suited region to define the beginning of the Last Interglacial and Late Pleistocene for global chronostratigraphic use. [ABSTRACT FROM AUTHOR]

In the search for a record of eustatic sea level change on glacial–interglacial timescales, the Seychelles ranks as one of the best places on the planet to study. Owing to its location with respect to the former margins of Northern Hemisphere ice sheets that wax and wane on orbital cycles, the local—or relative—sea level history is predicted to lie within a few meters of the globally averaged eustatic signal during the Last Interglacial period. We have surveyed and dated Last Interglacial fossil corals to ascertain peak sea level and hence infer maximum retreat of polar ice sheets during this time interval. We observe a pattern of gradually rising sea level in the Seychelles between ∼129 and 125 thousand years ago (ka), with peak eustatic sea level attained after 125 ka at 7.6 ± 1.7 m higher than present. After accounting for thermal expansion and loss of mountain glaciers, this sea-level budget would require ∼5–8 m of polar ice sheet contribution, relative to today's volume, of which only ∼2 m came from the Greenland ice sheet. This result clearly identifies the Antarctic ice sheet as a significant source of melt water, most likely derived from one of the unstable, marine-based sectors in the West and/or East Antarctic ice sheet. Furthermore, the establishment of a +5.9 ± 1.7 m eustatic sea level position by 128.6 ± 0.8 ka would require that partial AIS collapse was coincident with the onset of the sea level highstand. [ABSTRACT FROM AUTHOR]

Abstract: The Fronte Section, a well-exposed stratigraphic succession from southern Italy (Taranto area), provides an uninterrupted marine sedimentary record of MIS 5e. At this location, a highly expanded (8.5m thick) stratigraphic succession, unconformably overlying Middle Pleistocene marine clay deposits, provides evidence for sea-level fluctuations during the Last Interglacial. An integrated study of Fronte Section, including facies analysis, detailed macrofaunal and meiofaunal characterization, and sequence stratigraphy, is presented. The occurrence of Persististrombus latus (=Strombus bubonius) and other warm-water indicators (“Senegalaise” – “Senegalian” – guests of Gignoux, 1913), together with the presence of the dinocyst Polysphaeridium zoharyi and ten U-series dates on Cladocora caespitosa samples, permit an unequivocal MIS 5e age assignment to the upper part of the study succession. Above a stratigraphic unconformity marked by the boring coastal-lagoonal bivalve Pholas dactylus, the MIS 5e succession displays a first transgressive suite of brackish to shallow-marine deposits. These latter include highly fossiliferous muds rich in C. caespitosa, overlain by a fossil-rich calcarenite, 2m-thick, yielding warm-water “Senegalian” mollusks. Above this prominent stratigraphic marker (regionally called panchina), which is interpreted to represent a short-lived phase of sea-level stillstand or gentle fall during MIS 5e, renewed transgression took place, leading to the accumulation of middle-outer shelf muds, about 5m thick. The maximum flooding zone is clearly identified on the basis of the turnaround from a deepening-up to a shallowing-up trend. The upper part of Fronte Section records a second fossil-rich, sublittoral calcarenite containing warm-water mollusks, which is interpreted to reflect the subsequent phase of sea-level highstand, likely correlative with the MIS 5e plateau. [Copyright &y& Elsevier]

Abstract: Field observations and U-series ages reveal that Shark Bay, Western Australia (WA) has been inundated by the sea on at least three occasions during the Late Pleistocene/Holocene, resulting in a succession of marine deposits around the Bay. The exact age of these deposits has until now been problematic due to a lack of reliable and accurate age data. This study reports 16 new U-series coral dates from emergent reef deposits around Shark Bay, and point to an extended period of coral reef development during the peak of the last interglacial, marine isotope stage (MIS) 5e. This is attributed to enhancement of marine circulation within the reaches and basins, a result of higher sea levels and an absence of major sill and bank structures. Stromatolites are absent from the geological record within Shark Bay until the late Holocene, suggesting that sea levels and marine sedimentary processes that have operated during the present sea-level highstand are unique to this period. There is little direct evidence of fossil reef development occurring during interglacials of the middle/late Pleistocene (MIS 9/11). [Copyright &y& Elsevier]

The termination of the penultimate glacial period (TII) shows both similarities and differences to the last termination (TI). Both terminations show significant cold reversals in the postglacial warming trend. TI consists of a continuously increasing sea-level trend, whereas TII may demonstrate a sea-level reduction midway through the termination. We present a new, continuous sea-level record for TII derived from Red Sea δ18O records that supports the existence of the TII sea-level reversal. The record gives an unprecedented look at the structure of the TI sea-level reversal, which consists of an early highstand lasting several millennia in duration, followed by a 30 ± 12 m to 40 ± 12 m reduction in sea level and a stillstand of several millennia, before the final sea-level rise to the marine oxygen isotope stage (MIS) 5e interglacial. We suggest that there is a link between the sea-level reversal and internal, millennial-scale variability in the climate system. [ABSTRACT FROM AUTHOR]

The Beagle Channel crosses the southernmost tip of South America (Tierra del Fuego), connecting the South Atlantic with the Southeastern Pacific. Raised beaches occur up to 10 m above mean sea level (m a.m.s.l.), especially along the northern (Argentinian) shore, and have been dated using marine shells. The southern (Chilean) shore is well-known for its abundance of shell middens at different levels above the present shore, particularly along the island of Isla Navarino, but the relative sea level history in this glacially impacted landscape has not previously been investigated. In this study we present postglacial relative sea level changes on Isla Navarino, based on sediment cores from six lagoons, bogs or lakes, and stratigraphic investigations of three open sections, of which one is of MIS 5e age. In addition, one core from a lagoon in the south-western Beagle Channel has been analysed and a system of terraces was mapped in the north-western Beagle Channel. The analyses of the core sites have resulted in two tentative relative sea level curves, displaying a rapid sea level rise at 8500−6500 cal yr BP, amounting to ∼10 and 14 m in eastern and western Isla Navarino, respectively, and reaching levels of ∼8 and > 10 m, respectively, followed by a slow relative sea level fall. Our sea level observations have been compared with a range of modelling results of glacial-isostatic adjustments (GIA) for estimating timing of deglaciation and ice sheet thicknesses. Based mainly on the GIA modelling of the altitude of the MIS 5e beach sediments, situated at 13 m, we can conclude that no other uplift than GIA is needed to explain their altitude. Regarding the modelling of postglacial sea levels we can conclude that no model has been found that satisfies all of the observational evidence, but that deglaciation most likely preceded Northern Hemisphere main deglaciation by at least 3 kyr, which agrees with the deglaciation age of Isla Navarino (>16 000 cal yr BP). In addition, our model runs imply that the Patagonian and Tierra del Fuego ice sheet thicknesses were in the order of ∼1500 m. [ABSTRACT FROM AUTHOR]

Intertidal coralline red algal build-ups (Lithophyllum byssoides rims or ridges) are considered precise sea level markers and mostly used for Holocene sea level history. Several well-preserved patches of relict red algal ridges crop out along the north-west Sardinian coast (Mediterranean Sea, Italy) and have great potential in reconstructing the late Pleistocene sea level history of the western Mediterranean. The aim of this paper is to determine the sedimentary characteristics of the relict Lithophyllum byssoides build-ups cropping out along the Sardinian NW coast and to demonstrate how these can be used as past sea-level indicators. To establish a chronological framework for these deposits, luminescence dating (both quartz OSL and K-feldspar pIRIR 290) has been applied and allows for the Lithophyllum byssoides ridge formation to be assigned to Marine Isotopic Stage (MIS) 5e (132–112 ka). The studied relict ridges confirmed that MIS 5e sea-level was at least at 4 m above present, well matching the widely accepted last interglacial global sea-level curves. Hence, fossil Lithophyllum byssoides ridges can be used as stratigraphic and chronologic indicators of late Pleistocene sea-level. Moreover, the study has underlined that Lithophyllum byssoides may grow: (1) in sheltered places along high cliffy coasts forming bench-like structures, and (2) in high-energy environments on wave cut platforms around fallen blocks or potholes, first as isolated mounds and then merging to form reef-like structures. • Sedimentary characteristics of the relict Lithophyllum byssoides build-ups cropping out along the Sardinian NW coast • Use of Lithophyllum byssoides build-ups as past sea-level indicators • Dating of the relict Lithophyllum byssoides ridge using luminescence (both quartz OSL and K-feldspar pIRIR 290) • Fossil Lithophyllum byssoides ridges can be used as stratigraphic and chronologic indicators of late Pleistocene sea level. [ABSTRACT FROM AUTHOR]