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Climate instability in the Eemian Interglacial is gaining more and more evidence. One of such oscillations in the Beckentin record is indicated by the disappearance of the Cladocera and changes in macroremains at the beginning of E4a (Corylus phase). They confirm the shallowing of the reservoir, probably caused by climate changes, but not reflected in the palynological record. However, a significant oscillation observed in the first half of the E5 (Carpinus phase), ~5860 years after the boreal forests subsided and ~6290 years after the onset of interglacial forestation, suggests that, although not being an analogue of the OHO (Older Holsteinian Oscillations) in MIS 11c and the 8.2 ka cold event in the Holocene, it is very similar to these oscillations. The Eemian oscillation was noted also in the Bispingen profile in northern Germany, ~6500 years after the interglacial forestation. However, the course of vegetation changes there differs from that in Beckentin. The analysis of macroremains and Cladocera confirms the disappearance of rush and water vegetation in the water reservoir at that time in Beckentin. These results confirm that numerous climatic oscillations could have occurred in the Eemian Interglacial. [ABSTRACT FROM AUTHOR]

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]

The Last Interglacial period, Marine Isotope Stage 5e (MIS 5e ∼116–128 ka), is thought to have had a warmer, but less stable climate than the present interglacial. One key factor that has the potential to influence the ocean and climate is sea ice, but its presence and extent throughout MIS 5e is poorly constrained. Here we reconstruct the sea surface hydrography and sea ice variability in the Labrador Sea, a region influenced by the subpolar gyre (SPG) and where deep water formation occurs, in order to evaluate the potential of sea ice to drive or amplify ocean variability. We analysed biomarkers (highly branched isoprenoids, HBIs, and sterols), dinoflagellate cyst assemblages and stable oxygen isotopes from the late stages of MIS 6, throughout MIS 5e, into MIS 5d. Our results show that the late glacial MIS 6 was likely characterised by a thick multiyear sea ice cover. During the first phase of MIS 5e, the hydrography was highly variable. The initial 1500 years (128–126.5 ka) were characterised by the presence of a seasonal Marginal Ice Zone (MIZ) accompanied by subsurface warmth. As the sea ice retreated, cool, likely polar-sourced water dominated the surface and subsurface ocean (126.5–124 ka), until an abrupt surge of sea ice marked the final pulse of the remnants of the deglaciation. The second half of MIS 5e (124–116 ka) was characterised by a persistent inflow of warm water, only interrupted by incursions of cold water as summer insolation declined. Seasonal sea ice returned to the Eirik Drift during MIS 5d. We infer that sea ice variability throughout MIS 5e was coupled with the variability of the SPG. Especially the location of a proximal MIZ to the Labrador Sea convection region could have been important for SPG dynamics. In addition, the presence of sea ice at the transitions into and out of MIS 5e could point to its important role in modulating and enhancing the magnitude and coherence of climate signals at major climatic transitions. • The Eirik Drift was covered by perennial sea ice cover during the later stages of MIS 6. • MIS 5e sea ice variability was coupled with subpolar gyre (SPG) dynamics. • A marginal ice zone (MIZ) in the earliest MIS 5e may have helped maintain an active SPG. • Sea ice is not a prerequisite for SPG variability. • Sea ice may have amplified the climate signal of the last glacial inception. [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]

The Kos Plateau Tuff (KPT), was an enormous caldera forming eruption originating from a vent within the Kos/Nisyros/Yali volcanic complex, occurring at 161 ka. It is the largest recognised Late Quaternary eruption in the Eastern Mediterranean. With its distinctive, highly silicic chemical composition, the resulting ash deposits have been used both as a synchronous marker for palaeoenvironmental records in the region, and to provide information on eruption processes and magnitude. Here, we describe ash layers detected at multiple sites (deep-sea sequences and a terrestrial archaeological site) with ages generated by radiometric dating and sapropel correlation, to demonstrate the existence of a later, but geochemically similar eruption from the Kos volcano which has not previously been identified in proximal volcanic units. This eruption is dated to MIS 5e (∼124–129 ka), i.e. ∼40 kyr younger than the KPT. This tephra marks the start of MIS5e, and presents a rare opportunity to independently and precisely align paleoenvironmental records and archaeological sites during a time of rapid warming and sea level rise analogous to the present day. The presence of multiple tephras also implies the possibility of multiple eruptions during this period. This adds to our knowledge of the active and hazardous nature of Kos/Nisyros/Yali volcanic complex. • Identification of a tephra isochron at the onset of MIS 5e in the Eastern Mediterranean. • Identification of a highly silicic eruption younger than the KPT from the Kos volcano. • Important implications for Eastern Mediterranean chronostratigraphy, especially in relation to marine records and the KPT • Robust age control on the MIS 5e Kos eruption provide a modelled age of 124.9 ± 2 ka. • Estimate an eastward dispersal of MIS 5e Kos tephra and the potential area of detecting this tephra. [ABSTRACT FROM AUTHOR]

Facies analysis, together with palynostratigraphic studies of the Kioroshi Formation, which lies beneath the northern Chiba area of the Kanto Plain of central Japan, reveal the sedimentary processes in the fluvial to coastal settings during marine isotope stage (MIS) 5e in this region. The depositional sequence of the Kioroshi Formation comprises a lower incised valley system and an upper barrier island system. The incised valley system consists of fluvial, estuary, and central basin facies with sandbar facies in the baymouth area. In the study area, the overlying barrier island system includes flood tidal delta, spit, and lagoon facies. These facies form part of the barrier island system known as Paleo-Tokyo Bay, which covered the present-day Kanto Plain. On the basis of palynostratigraphic correlation with the oxygen isotope curve in an offshore core (MD01-2421), the fluvial and estuary facies, together with the lower half of the central basin facies of the incised valley system are interpreted to have accumulated during a sea level rise in the early stage of MIS 5e. The baymouth sandbar also developed and retrograded with the rising sea level and was abruptly covered by the central basin facies during the middle stage of MIS 5e, probably due to the migration of the sandbar to the outer-bay area. The abrupt change corresponds with the initial stage of development of the barrier island system. The landward (westward) retreating bay ravinement erosion resulted in the transition to the barrier island system during middle MIS 5e. Maximum transgression also occurred during middle MIS 5e. The back-barrier lagoon was infilled during the late stage of MIS 5e. The sedimentary processes of the Kioroshi Formation are almost in accordance with the marine isotope curve. [ABSTRACT FROM AUTHOR]

The Last Interglacial in the Arctic region is often described as a time with warmer conditions and significantly less summer sea ice than today. The role of Atlantic water (AW) as the main oceanic heat flux agent into the Arctic Ocean remains, however, unclear. Using high-resolution stable isotope and faunal records from the only deep Arctic Gateway, the Fram Strait, we note for the upper water column a diminished influence of AW and generally colder-than-Holocene surface ocean conditions. After the main Saalian deglaciation had terminated, a first intensification of northward-advected AW happened (~124 ka). However, an intermittent sea surface cooling, triggered by meltwater release at ~122 ka, caused a regional delay in the further development towards peak interglacial conditions. Maximum AW heat advection occurred during late MIS 5e (118.5-116 ka) and interrupted a longer-term cooling trend at the sea surface that started from about 120 ka on. Such a late occurrence of the major AW-derived near-surface warming in the Fram Strait - this is in stark contrast to an early warm peak in the Holocene - compares well in time with upstream records from the Norwegian Sea, altogether implying a coherent development of south-to-north ocean heat transfer through the eastern Nordic Seas and into the high Arctic during the Last Interglacial. [ABSTRACT FROM AUTHOR]

Molluscs incorporate negligible uranium into their skeleton while they are living, with any uranium uptake occurring post-mortem. As such, closed-system U-series dating of molluscs is unlikely to provide reliable age constraints for marine deposits. Even the application of open-system U-series modelling is challenging, because uranium uptake and loss histories can affect time-integrated uranium distributions and are difficult to constrain. We investigate the chemical and isotopic distribution of uranium in fossil Tridacna gigas (giant clams) from Marine Isotope Stage (MIS) 5e (128–116 ka) and MIS 11 (424–374 ka) reefs at Huon Peninsula in Papua New Guinea. The large size of the clams enables detailed chemical and isotopic mapping of uranium using LA-ICPMS and LA-MC-ICPMS techniques. Within each fossil Tridacna specimen, marked differences in uranium concentrations are observed across the three Tridacna growth zones (outer, inner, hinge), with the outer and hinge zones being relatively enriched. In MIS 5e and MIS 11 Tridacna , the outer and hinge zones contain approximately 1 ppm and 5 ppm uranium respectively. In addition to uptake of uranium, loss of uranium appears prevalent, especially in the MIS 11 specimens. The effect of uranium loss is to elevate measured [ 230 Th/ 238 U] values with little effect on [ 234 U/ 238 U] values. Closed-system age estimates are on average 50% too young for the MIS 5e Tridacna, and 25% too young for the MIS 11 Tridacna . A complex, multi-stage uptake and loss history is interpreted for the fossil Tridacna and we demonstrate that they cannot provide independent, reliable geochronological controls on the timing of past reef growth at Huon Peninsula. [ABSTRACT FROM AUTHOR]

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]

A fossil assemblage collected around 3.5 m amsl from Ezeiza, Buenos Aires province, have AMS 14 C ages of ca. 33,000 to ca. 40,000 yr BP, whereas in the literature is a report of a conventional 14 C age of >43,000 yr BP. An OSL age from the overlying deposit corresponds to ca. 22,000 yr. The samples contain marine fossils: mollusks, balanids and corals ( Astrangia ). La Coronilla (Uruguay, attributed to MIS 5e) is the locality most related to Ezeiza faunistically, despite is not the nearest one. In consequence, the relationship should be addressed to a more similar age and environment than others. The fauna indicates a higher water temperature than today. In Ezeiza exclusively cold water taxa are absent, and we found seven warm taxa with their southern distribution limit displaced northwards today, plus other six at their southern distribution limit. Around 60% of all the species and more than 70% of the individuals are of warm-temperate waters. In sum, although prima facie the numerical ages would locate the deposit in MIS3, faunistic, temperature, and height evidences show that the Ezeiza mollusk assemblage belong to MIS5e. A stronger than presently Brazil warm current, reaching Southern latitudes, may explain the changes in geographical ranges. [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]

Recent and sub-recent laminated tufa stromatolites can contain high-resolution δ 18 O records of in-stream temperature change. Fossil tufa stromatolites are therefore key targets for reconstructing terrestrial palaeoclimatic, but so far only a few examples have been published. In this research, we studied a 2.5-cm-radius tufa stromatolite from the Eemian of the Somme Basin, Northern France. We show (1) that high-resolution sampling of fossil laminated tufas is highly reproducible. We demonstrate (2) that within the limitations of the δ 18 O method, NW European Eemian seasonality was essentially similar to the present day. Perhaps most important, we show (3) that precise observations from thin section that match the position of lamina boundaries with the position of reversals in direction of δ 18 O values are a record of the style or intensity of seasonality. In this French tufa stromatolite, abrupt δ 18 O reversals do not coincide with sharp lamina boundaries; rather, the lamina boundaries occur where δ 18 O values are either gradually decreasing or increasing. We interpret this to be a record of abrupt changes in the growth rate, accelerating in spring or early summer and decelerating in late autumn or early winter. This contrasts with a published montane record from the Eemian of Greece, where lamina boundaries and δ 18 O reversals do coincide, interpreted as more extreme seasonality caused by cessations in growth due to summer aridity or winter cold. We thus propose this criterion as a method to help identify regional styles of seasonality in tufa stromatolites. [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]

The comparison of optically stimulated luminescence (OSL) ages of different grain-size fractions has given rise to conflicting results over recent years. To test the reliability and validity of OSL dating of fine- and coarse-grained fractions, 25 samples were collected from a 46-m sediment core taken from the southwestern coast of Korea, which contained two typically fine-grained tidal units separated stratigraphically by a coarse-grained sand and gravel layer. A single aliquot regenerative dose (SAR) procedure was applied to chemically separated fine- (4–11 μm, n = 16) and coarse- (90–212 μm, n = 24) grained quartz. The ages of coarse-grained quartz in the upper unit were relatively consistent with those of fine-grained quartz in the same unit of Holocene age (12–0 ka). In contrast, in the lower unit the coarse quartz fraction OSL ages are 30–60% (mean 46%) lower than the fine quartz fraction ages. OSL ages for all fine-grained quartz in the lower unit (139–110 ka) were in good agreement with the last interglacial sea-level highstand [Marine Isotope Stage (MIS) 5e]. However, all OSL ages for coarse-grained quartz in this lower unit (90–45 ka) were younger, corresponding broadly to the last glacial period (MIS 4 and 3). OSL ages obtained for fine-grained quartz were in agreement with indirect age controls provided by lithological and palynological data, implying that the use of the SAR protocol to date fine-grained quartz is appropriate for age control of coastal sediments extending to the last interglacial period. The discrepancies between the ages of different grain-size fractions may have arisen from early saturation of the natural signal and, in some cases, from contamination of the feldspar signal in the coarse quartz. However, more research is required to assess the reliability of OSL ages for fine-grained quartz obtained from the high-dose linear region of the dose response curve. [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]

The privileged location of Santa Maria Island (Azores archipelago) in the middle of the North Atlantic makes the fossiliferous outcrops on this island of utmost importance to gain a better understanding of how coeval living communities relate to the broader evolutionary and biogeographic history of the Atlantic basin during the late Neogene and the Quaternary. Here we focus on this island's MIS 5e fossil record, offering a comprehensive review on the palaeobiodiversity, palaeoecology and palaeobiogeography of the biota living in the mid North Atlantic during this interglacial. Several studies in oceanic islands stress the huge impact of sea level changes on insular communities. Pleistocene sea-level changes occur during the short-time events known as “Terminations” (associated to glacial/interglacial shifts) as well as with the onset of glaciations (associated to interglacial/glacial shifts). Both are responsible for extinctions and local disappearance of species, bottleneck effects and formation of new species, resulting in community structure changes. This work increases the number of fossil marine taxa reported from the Last Interglacial deposits of Santa Maria to 143 species. All the 19 new records are molluscs (13 gastropods and 6 bivalves), thus increasing the number of fossil molluscs to 136 species. Although thermophilic members of the “Senegalese” tropical fauna were found in these deposits, many of the most emblematic species (e.g., Persististrombus latus (= Strombus bubonius ), Cymbula safiana , Harpa doris , Cardita senegalensis , Barbatia plicata , Ctena eburnea or Hyotissa hyotis ) are absent, suggesting that they did not reach the Azores. Our results indicate that the main differences between the species composition of the MIS 5e and the present-day shallow-water Azorean communities are probably due to the dropping of sea surface temperature associated with the onset of the last glaciation, which had both direct and indirect effects on species ecology. A group of 21 thermophilic species was directly affected by the lower sea surface temperature, whereas a group of four sand-associated species was indirectly but similarly affected by the lowering of the sea level. Both groups have locally disappeared from the Azores. However, none of the extant endemic species found on the studied MIS 5e outcrops was apparently affected by the lowering SST. In contrast to the biogeographical relationships of the recent Azorean shallow marine molluscs, which are predominantly with the Mediterranean Region, Portugal and with the Madeira and Canary Islands archipelagos, the palaeobiogeographical relationships of the MIS 5e Azorean marine molluscs are mainly with Canaries and West Africa. Despite the general low similarity of the biogeographical relationships between the Azores and Cape Verde Archipelago, on both the recent and the MIS 5e analysis, this similarity is nevertheless higher for the MIS 5e mollusc assemblages, emphasizing the role of Cape Verde as an important source of warm-water species during the Last Interglacial. [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]

This is the first report of an OSL (optically stimulated luminescence) -dated Eemian marine deposit along the southwest coast of Korea. It was discovered on the Baeksu intertidal shoreface/tidal flat system. Based on the analysis of (up to 46-m-long) drilled cores, the Baeksu tidal deposits can be divided into four sedimentary units. In ascending order these are: 1) basal fluvial gravels, 2) Eemian tidal mud, 3) gravel lag/paleosol, and 4) Holocene tidal deposits. The Eemian tidal sequences were encountered at a core interval of −20 to −38 m below mean sea level, the OSL ages ranging from 138 to 110 ka. Pollen analyses reveal a higher AP (arboreal pollen) to NAP (nonarboreal pollen) ratio, suggesting warm climate conditions similar to that of the Holocene. In addition, marine dinoflagellates and salt marsh pollen were found, these palynofloral records thus also attesting to marine influence in the deposits. In expectation that the Eemian tidal mud succession occurs on a wider geographic scale, the deposit is allocated the stratigraphic name Baeksu Formation (Eemian), the stratotype locality being situated at −20 m below the surface at the Baeksu borehole site. The presence of Eemian tidal muds along the west coast of Korea, which correlate with marine strata in the western Yellow Sea and Bohai Sea, explicitly reveals the occurrence of marine incursions into the eastern margin of the paleo(?)-Yellow Sea land during the last interglacial. [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]

Homo sapiens dispersals out of Africa are often linked to intensifications of the African and Indian Summer Monsoons. Current models advocate that dispersals along the "southern-route" into Arabia occurred during Glacial Termination-II (T-II), when lower sea-level and reduced Bab-al-Mandab width increased the likelihood of crossing. The precise phasing between sea-level and monsoon precipitation is thus key to assess the likelihood of a successful crossing or the behavioural and technological capacities that facilitated crossing. Based on a precisely-dated stalagmite record from Yemen, we reveal a distinct phase-lag of several thousand years between sea-level rise and major monsoon intensification. Pluvial conditions in Southern Arabia during MIS 5e lasted from ∼127.7 to ∼121.1 ka BP and occurred when sea-levels were already higher than at present. Based on our observations, we propose three models for the dispersal of H. sapiens which all have pertinent implications for our understanding of human technological and behavioural capacities during MIS 5e. • Timing of MIS 5e monsoon intensification in Southern Arabia (SAHP 4) confined to 127.7-121.1 ka BP. • SAHP 4 represents the most substantial increase of rainfall in the last 130 ka BP. • The onset of monsoon intensification lagged sea-level rise. [ABSTRACT FROM AUTHOR]

Controlled by ecological and physical factors, marine species distribution may vary due to global climatic changes that result from range expansion or contraction (the latter caused by local disappearances, i.e., extirpations). Spanning from 13° to 39°N, the Macaronesian region encompasses five archipelagos located within warm-temperate to tropical climatic zones and influenced by a surface water current regime that favours a N–S range expansion of marine species. The extensive and well-preserved Macaronesian fossil record makes these islands excellent candidates for evolutionary studies. It documents a northward range expansion of tropical species with a Cabo Verdean-Mauritanian-Senegalese biogeographic provenance during the Last Interglacial (LIG). For the first time, a thorough revision and update of marine molluscs' checklist from the Macaronesian archipelagos for the LIG is presented. On this basis, we hypothesize that the range expansion occurred during the last phase of glacial Termination 2 and was enhanced by ephemeral sea surface currents that created windows of opportunity for the long-distance dispersal of marine species along sweepstake routes. During these short intervals of time, numerous tropical and subtropical species expanded their geographic range northwards, towards what today are subtropical and temperate archipelagos. Simultaneously, however, a smaller number of northern species expanded their ranges southward, some reaching Cabo Verde. This work yields a set of 24 mollusc "ecostratigraphic indicators" (10 bivalve and 14 gastropod species) that are important to identify fossiliferous deposits from the Last Interglacial epoch in Macaronesian archipelagos. Longitudinal range expansions from West African shores to the Cabo Verde archipelago and the Canary Islands were also detected. These are related to coeval weaker upwelling systems which now constitute effective barriers for the exchange of species/individuals between continental and insular shores (e.g., Senegal/Cabo Verde; Morocco/Canaries). Finally, an ecological filter-effect also existed, which we associate with the increasingly longer distances to cover, as many of the most typical representatives of the warm water fauna with Cabo Verde/Senegalese affinities failed to reach the northern Azores and Madeira archipelagos. • A full checklist of the LIG shallow water marine molluscs from the Macaronesian archipelagos is presented. • A new 24 ecostratigraphic indicator's list is proposed for the Macaronesian archipelagos. • The most probable routes of dispersal followed by the shallow water marine molluscs within the Macaronesian are shown. • Different surface ocean currents must have taken place during LIG to allow the range expansion in the NE Atlantic. [ABSTRACT FROM AUTHOR]

Abstract: Marine Isotope Stage (MIS) 11 was possibly the longest (∼423,000–362,000 yr ago) and warmest interglacial of the entire Quaternary Period. This resulted from a special arrangement of Earth''s orbital parameters-similar to the present interglacial (MIS 1)-suggesting that MIS 11 provides an analogue for future natural climate forcing and sea levels. Although precise documentation of MIS 11 sea level history is, therefore, crucial – especially considering additional impetus from anthropogenic warming – the maximum MIS 11 sea level remains highly contentious. Estimates from onshore indicators have ranged from below present sea level to about +20m, resulting from uncertainties in reliability of sea level indicators, estimates of their subsequent displacement by vertical crustal motion and in dating. We used a clear and unambiguous sea level indicator (interface between subtidal and intertidal deposits) in well exposed, regressive raised shoreline deposits along South Africa''s southern coast. The coast is stable in terms of tectonic setting and falls within a zone of low predicted glacio-isostatic adjustment (GIA) and low sensitivity for plausible model parameters. The sea level indicators were directly dated using thermally transferred optically stimulated luminescence (TT-OSL), which gave a mean age of ∼390ka, corresponding with MIS 11. We determined a precise maximum elevation of +14m for the MIS 11 sea level indicator, which corrected for minor crustal uplift and GIA yielded a eustatic sea level of +13m ±2m. The complete MIS 11 transgressive/regressive shoreline succession is preserved and the wave-cut platform extends 950m inland from the present shoreline, indicating a prolonged highstand. We have also documented sea level fluctuations during MIS 11, including an earlier (lower) highstand close to present sea level, which may explain the lower elevation range of some previous estimates. At one locality, MIS 11 deposits form a sea cliff against which MIS 5e sediments (at an elevation of +6.2m) abut. The +13m MIS 11 sea level tallies with total melting of the Greenland and West Antarctica ice sheets, regarded as most susceptible to melting. Our data predict notably higher sea levels in the future, regardless of anthropogenic influence on climate. [Copyright &y& Elsevier]

Abstract: The growing interest in quantification of vertical ground motion stems from the need to understand in detail how the Earth''s crust behaves, for both scientific and social reasons. However, only recently has the refinement of dating techniques made possible the use of paleoshorelines as reliable tools for tectonic studies. Although there are many local studies of Quaternary vertical motions of coastlines, we know of no comprehensive worldwide synthesis. Here we provide a compilation of 890 records of paleoshoreline sequences, with particular emphasis on the last interglacial stage (Marine Isotopic Stage [MIS] 5e, ~122ka). The quality of dating MIS 5e makes it a reliable marker to evaluate vertical ground motion rates during the late Quaternary on a global scale. The results show that most coastal segments have risen relative to sea-level with a mean uplift rate higher than 0.2mm/yr, i.e. more than four times faster than the estimated eustatic drop in sea level. The results also reveal that the uplift rate is faster on average for active margins than for passive margins. Neither dynamic topography nor glacio-hydro-isostasy may explain sustained uplift of all continental margins, as revealed by the wide distribution of uplifted sequences of paleoshorelines. Instead, we suggest that only plate-tectonic processes reconcile all observations of Quaternary coastal uplift. We propose that long-term continental accretion has led to compression of continental plates and uplift of their margins. Therefore this study concludes that plate-tectonics processes impact all margins and emphasizes the fact that the notion of a stable platform is unrealistic. These results therefore seriously challenge the evaluation of past sea levels from the fossil shoreline record. [Copyright &y& Elsevier]

Abstract: The Last Interglacial (Marine Isotopic Stage or MIS 5e) surface ocean heat flux from the Rockall Basin (NE Atlantic) towards the Arctic Ocean was reconstructed by analysing dinoflagellate cyst (dinocyst) assemblages in four sediment cores. Together with records of stable isotopes and ice-rafted detritus, the assemblage data reflect the northward retreat of ice(berg)-laden waters and the gradual development towards interglacial conditions at the transition from the Saalian deglaciation (Termination II) into MIS 5e. At the Rockall Basin, this onset of the Last Interglacial is soon followed by the appearance of the thermophilic dinocyst species Spiniferites mirabilis, with relative abundances higher than those observed at present in the area. North of the Iceland-Scotland Ridge, however, S. mirabilis only appears in significant numbers during late MIS 5e, between ∼118 and 116.5 ka. Hence, fully marine Last Interglacial conditions with most intense Atlantic surface water influence occurred during late MIS 5e in the Nordic seas, and consequently also farther north in the Arctic Ocean, and at times when northern hemisphere summer insolation was already significantly decreased. The stratigraphic position of this Late Interglacial optimum is supported by planktic foraminifers and contrasts with the timing of the early Holocene climatic optimum in this area. We interpret the delayed northward expansion of Atlantic waters towards the polar latitudes as a result of the Saalian ice sheet deglaciation and its specific impact on the subsequent water mass evolution in this region. [Copyright &y& Elsevier]

Abstract: Marine sediments contain important archives of past ocean and climate changes, but at high latitudes the absence of carbonate has prevented the construction of accurate chronological models. We have begun a study to (1) determine the accuracy of luminescence ages in deep-sea marine sediments, e.g. by comparison with marine oxygen isotope stratigraphy where possible, (2) describe changes in sedimentation rate through time, and (3) test whether it is possible to date back to marine isotope stage 5e (MIS 5e). We show here that optical dating of fine grains of quartz from the central Sea of Okhotsk is able to provide an accurate and precise chronology for the reconstruction of the palaeoceanic and palaeoclimatic environment at our site. The upper 6.5m of the 18.42m long core MR0604-PC07A is believed, based on its magnetic susceptibility and the oxygen isotope (δ18O) records to contain the last ∼150ka. Forty OSL samples were taken from this upper part of the core. The single-aliquot regenerative-dose (SAR) procedure is used for equivalent dose (De) determination. The luminescence characteristics of fine-grained quartz (4–11μm) extracted from the core are described. The OSL signal is dominated by the fast component and a dose recovery test shows that we can accurately measure a known dose given in the laboratory prior to any heat treatment. Dose rates were determined using high-resolution gamma spectrometry, and vary between 0.4 and 1.6Gy/ka. The OSL ages from this section lie between ∼140ka and ∼15ka and are in very good agreement with the δ18O stratigraphy up to MIS 5e. A clear change in sedimentation rate is identified: between ∼139 and 110ka, the sedimentation rate was ∼0.09m/ka, but then from ∼110 to 15ka, the sedimentation rate decreases to a constant value of ∼0.04m/ka. Our data confirm that OSL dating using widely distributed fine-grain quartz has great potential for dating deep-sea sediments. Because luminescence methods use clastic materials, they do not depend on the presence of biogenic carbonate. As a result it is now likely that we can establish a chronology in regions of the ocean that were previously undatable. [Copyright &y& Elsevier]

Marine Isotope Stage (MIS) 5e (130–116 ka) represents an important 'process analogue' for understanding the climatic feedbacks and responses likely active under future anthropogenic warming. Reconstructing the Southern Ocean (SO) palaeoenvironment during MIS 5e and comparing it to the present day provides insights into the different responses of the SO sectors to a warmer climate. This study presents new records from seven marine sediment cores for MIS 5e together with their surface sediment records; all cores are located south of 55 oS. We investigate changes in diatom species assemblage and the accompanying variations in sea surface temperatures, winter sea-ice extent (WSIE) and glacial meltwater flux. All records show warmer conditions and a reduced WSIE during MIS 5e relative to the surface sediments. While the Pacific and Indian Sector records present very stable conditions throughout MIS 5e, the Atlantic Sector records display much more changeable conditions, particularly with respect to the WSIE. These variable conditions are attributed to higher iceberg and glacial meltwater flux in the Weddell Sea. This evidence for increased iceberg and glacial meltwater flux in the Weddell Sea during MIS 5e may have significant implications for understanding the stability of the West Antarctic Ice Sheet, both during MIS 5e and under future warming. • The Southern Ocean was warmer and had less sea ice during MIS 5e than in the modern. • First MIS 5e diatom record from within the seasonal sea-ice zone. • Atlantic Sector saw great variability in environmental conditions during MIS 5e. • High iceberg and glacial meltwater flux from the Weddell Sea during MIS 5e. [ABSTRACT FROM AUTHOR]

A nearly complete skeleton of an elephant calf was excavated between 2012 and 2014 from breccia deposits in a vertical karstic cavity named Cova del Rinoceront, exposed during limestone quarrying. The skeleton was found in the 120 cm-thick breccia layer III (Unit 1) of the 11 m-long sedimentary sequence filling the cavity. IRSL (128–129 ka) and AAR (126–142 ka) dating indicate that the layer was probably deposited during MIS 5e (∼115–135 ka). The diagnostic morphological traits of the occlusal surface of the molariform teeth, their position in the tooth progression and wear indicate that the skeleton belongs to a Palaeoloxodon antiquus calf about 5 years old, with a putative height at the shoulder of about 178–187 cm and a weight of about 1450–1500 kg. The sex cannot be confidently determined because the tusks were poorly preserved and the young age reduces the diagnostic value of the pelvis girdle. The rarity of calf skeletons in the fossil record of continental straight-tusked elephants renders the Cova del Rinoceront individual of great interest for better understanding the ontogenetic processes in continental straight-tusked elephants. The results obtained evidence, on the one hand, the difficulties entailed in properly assessing the ontogenetic growth process, given the low number of fully informative specimens of straight-tusked elephants known to date. On the other hand, they indicate an early beginning of distal epiphyseal fusion in humerus and tibia and of the proximal epiphysis in radius. Moreover, the nearly fused lateral epicondylus and condylus and the unfused and separate diaphysis and epiphysis on the medial side of the right femur suggest not only that fusion patterns may show high levels of intraspecific variation, but also that the process of epiphyseal fusion may vary in the homologous bones of a single individual. Notwithstanding the limitations resulting from the preservation status of the calf bones, our analysis yielded sufficient information to infer the ontogenetic age of the Cova del Rinoceront elephant, estimate its body mass and evaluate allometric growth in P. antiquus long bones. We obtained slightly different results when analysing samples that did or did not include the Cova del Rinoceront calf. In the former sample, confident isometry was limited to a few predictors but could not be excluded because for most of the independent variables, isometry and negative correlation were roughly balanced. Most of the dependent and independent variables showed the same or a similar scale ratio, but fewer responded almost similarly to bending stresses imposed by loading under their own weight. When the calf was excluded from analysis, negative or possibly negative correlations and variables responding almost similarly to bending stresses imposed by loading under their own weight prevailed. However, the hypothesis that some changes in limb bone proportions occurred during ontogenetic growth requires further support from an analysis of large samples of fully informative mature and immature P. antiquus individuals. • The CdR calf (MIS 5) is the first complete skeleton of P. antiquus studied to date. • The skeleton is of great interest for analysing ontogenetic processes in P. antiquus.. • We evidenced a high intra-individual variation in long bone epiphysis fusion timing. • Some changes in limb bone proportions during ontogenetic growth could be suggested. • The calf was a 5 years old individual, weighting about 1450-1500 kg. [ABSTRACT FROM AUTHOR]

The Last Interglacial warm period, the Eemian (ca. 130–116 thousand years ago), serves as a reference for projected future climate in a warmer world. However, there is a limited understanding of the seasonal characteristics of interglacial climate dynamics, especially in high latitude regions. In this study, we aim to provide new insights into seasonal trends in temperature and moisture source location, linked to shifts in atmospheric circulation patterns, for northern Fennoscandia during the Eemian. Our study is based on the distribution and stable hydrogen isotope composition (δD) of n -alkanes in a lake sediment sequence from the Sokli paleolake in NE Finland, placed in a multi-proxy framework. The δD values of predominantly macrophyte-derived mid-chain n -alkanes are interpreted to reflect lake water δD variability influenced by winter precipitation δD (δD prec), ice cover duration and deuterium (D)-depleted meltwater. The δD values of terrestrial plant-derived long-chain n -alkanes primarily reflect soil water δD variability modulated by summer δD prec and by the evaporative enrichment of soil and leaf water. The δD prec variability in our study area is mostly attributed to the temperature effect and the moisture source location linked to the relative dominance between D-depleted continental and polar air masses and D-enriched North Atlantic air masses. The biomarker signal further corroborates earlier diatom-based studies and pollen-inferred January and July temperature reconstructions from the same sediment sequence. Three phases of climatic changes can be identified that generally follow the secular variations in seasonal insolation: (i) an early warming trend succeeded by a period of strong seasonality (ii) a mid-optimum phase with gradually decreased seasonality and cooler summers, and (iii) a late climatic instability with a cooling trend. Superimposed on this trend, two abrupt cooling events occur in the early and late Eemian. The Sokli δD variability is generally in good agreement with other North Atlantic and Siberian records, reflecting major changes in the atmospheric circulation patterns during the Eemian as a response to orbital and oceanic forcings. • Terrestrial and aquatic n -alkanes δD reflect temperature and moisture source seasonality. • Orbital-driven changes in atmospheric circulation influence the δD variability. • δD records reveal changes in the dominance between oceanic and polar/continental air masses. • Colder winters occur in the early Eemian and colder summers in the late Eemian. • Two abrupt cooling events are linked to disturbances in the North Atlantic. [ABSTRACT FROM AUTHOR]

Abstract: A detailed geomorphologic and morphostratigraphic investigation of raised marine terraces at Cape Cuvier, Western Australia, reveals two morphologically distinct units. A lower, well-developed accretional reef terrace between 3 and 5.5 m above MLWS (mean low-water springs; hereafter denoted as “+”) represents an extended interval of stable sea level. An upper erosional terrace and incipient coralgal rim between +8.5 to 10.5 m represents a brief sea-level stillstand at this higher elevation. These features suggest the lower and upper terraces developed during discrete sea-level events. In an attempt to better define the timing of emplacement of each marine unit, 20 coral samples collected along vertical and lateral reef growth axis from both terraces were analysed with U-series dating. Unfortunately, all coral samples exhibited elevated δ 234Uinitial values, suggesting that pervasive uptake of 234U-enriched uranium and 230Th thorium had occurred. Despite the shortcomings of absolute dating, a succession of events can be resolved though morphostratigraphic relationships. Comparison of the facies relationships, coral growth, and morphostratigraphic features between the lower and upper terraces indicates that an early to mid MIS 5e stillstand at +3 to 5 m was followed by a late rise to +8.5 to 10.5 m. This agrees with an emerging global view of MIS 5e sea-level history derived from stable carbonate platforms, rejecting the hypothesis that these higher sea-level benchmarks are an artefact of localized tectonic processes. [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]

Abstract: Quartz optically stimulated luminescence (OSL) forms the basis for the chronology of Weichselian ice advances in Arctic Eurasia developed over the last few years. There is almost no age control on this chronology before 40ka, except for some marine sediments correlated with marine isotope stage (MIS) 5e on the basis of their palaeofauna. Results from more southern latitudes have shown that dose estimates based on quartz OSL and the single aliquot regenerative (SAR) dose procedure may underestimate the age of MIS 5e deposits. Here we use the same method to date well-described marine sediments, thought to have been deposited during the very beginning of the Eemian interglacial at ∼130ka, and exposed in two sections on the river Sula in northern Russia. Various quality-control checks are used to show that the OSL behaviour is satisfactory; the mean of 16 ages is 112±2ka (σ=9ka). This represents an underestimate of ∼14% compared to the expected age, a discrepancy similar to that reported elsewhere. In contrast to SAR, the single aliquot regeneration and added (SARA) dose procedure corrects for any change in sensitivity during the first OSL measurement. The SARA results are shown to be ∼10% older than those from SAR, confirming the geological age estimate and suggesting that SAR ages may underestimate older ages (larger doses), despite their good performance in the younger age range. [Copyright &y& Elsevier]

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]

In Hudson Bay Lowlands (HBL), the Wisconsinan tills are often underlain by organic-bearing nonglacial deposits formed during episodes of significant reduction of ice volumes or complete ice-free conditions in this region. The subtill nonglacial deposits, often correlated with the Missinaibi Formation, are beyond the method limit of radiocarbon dating in general. As such, they have been a subject of debates for their stratigraphy and associated climatic conditions owing to poor age constraints. Extensive studies were undertaken on a subtill argillaceous lacustrine deposit uncovered recently on the Winisk River. This 9 m thick organic-rich deposit, referred to as the Webequie Beds, was dated at 121 ± 9 ka, 126 ± 24 ka and 105 ± 11 ka using optically stimulated luminescence (OSL) dating method and correlated with the Last Interglacial (LIG) or Marine Isotope Stage (MIS) 5e. Pollen and plant macrofossils suggest spruce boreal forests along with extensive wetlands, not unlike what exists in the HBL today. Of particular note is the sporadic rise of birch in the upper part of the pollen sequence, interpreted as a response to the availability of frequent forest clearance by fires under a warmer climate. The birch zone is noteworthy because it corresponds to the development of conspicuous S-rich, ferromagnetic nodules (0.125–1.5 mm diameter) in the lake sediment. The nodules comprise native sulphur and greigite (Fe 3 S 4), along with iron oxyhydroxide goethite and lepidocrocite. They likely resulted from significant warming during this interval that enhanced microbial sulphate reduction and increased the release of H 2 S, an essential component for the formation of the S minerals in the lake. Besides the strengthened microbial metabolization, a prolonged summer lake stratification and development of an anoxic bottom water also likely promoted the sulphate reduction. Although confirmation is needed, the warming probably linked to the LIG thermal maximum (∼120 ka) when a climate with a higher summer temperature than today prevailed. A similar subtill nonglacial deposit on the Little Current, a tributary of the Albany River, was also examined for comparison. Apart from a similar pollen flora, S-rich nodules were also recovered near a horizon OSL dated at 118 ± 13 ka comparable to the LIG thermal maximum. Results of this study provide new insights into the stratigraphy and climatic conditions of the LIG in the HBL but also help better understand the behavior and dynamics of the Laurentide Ice Sheet during the Late Pleistocene. • First documentation of subtill nonglacial deposits for the Winisk River, Hudson Bay Lowlands (HBL). • Only site of the HBL where multiple luminescence dates (OSL) indicate a Last Interglacial or MIS 5e affinity. • First report on S-rich ferromagnetic nodules and their development interpreted as a result of significant warming. • Climatic conditions inferred from multiple lines of evidence including palaeobotany, sedimentology and geochemistry. • Provide new insights into the stratigraphy and climatic conditions associated with the Missinaibi Formation of the HBL. [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]