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See detailBiological nitrate utilization in south Siberian lakes (Baikal and Hovsgol) during the last glacial period: the influence of climate changes on primary productivity
Watanabe Nara, F.; Watanabe, T.; Kakegawa, T. et al

in Quaternary Science Reviews (in press)

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See detailLate Quaternary evolution of sediment provenances in the Central
Fagel, Nathalie ULg; Not, Christelle; Gueibe, Jonathan et al

in Quaternary Science Reviews (in press)

Mineral assemblage, trace element content and Nd and Pb isotope signatures were analysed on the fine fraction (<20 mm) of sedimentary records from the Northern Mendeleev Ridge in the Central Arctic Ocean ... [more ▼]

Mineral assemblage, trace element content and Nd and Pb isotope signatures were analysed on the fine fraction (<20 mm) of sedimentary records from the Northern Mendeleev Ridge in the Central Arctic Ocean. Our aimwas to identify the detrital particle provenance and to interpret the changes over the past w250 ka in the relative contribution of the different source-areas in relation to paleoenvironmental conditions. The clay mineral assemblage and the Nd and Pb isotope signatures depict systematic changes over the Late Quaternary. The bulk mineralogy exhibits increases in the relative contribution of carbonate minerals vs. silicates in interglacial/deglacial intervals. In glacial intervals, the mineral assemblage of the <20 mm fraction is characterised by an enrichment in kaolinite, counterbalanced by a decrease in illite. The Nd and Pb isotope signatures of <20 mm fraction are interpreted using a three end-member mixing model, involving crustal supplies from North America and Canada, from the Siberian margin and some from volcanic material. A compilation of geochemical signatures of geological terraines surrounding the Arctic Ocean allowed each end-member to be assigned a representative signature, averaging the signal of the eroded terraines. The Suspended Particulate Matter (SPM) of the MacKenzie River represents an average signature of the sedimentary supplies delivered from the North American platform and Canadian margin. The SPM of the Lena River reflects the mean sedimentary signature of the Siberian platform. The Okhotsh-Chukotka province from the Eastern border of Siberia is identified as the most probable volcanic source. Late Quaternary evolution of the estimated relative contribution of the three end-members confirms that the sediment provenances in the Central Arctic Ocean remain close to the current conditions during past interglacials/deglacials MIS1e3, MIS5/TII and MIS7/TIII. In contrast, glacial conditions (MIS4 and MIS6) record minimum supplies from the American margin, associated with increased volcanic contribution, to the Mendeleev Ridge core location suggesting a different sea-ice circulation associated with a low sea-level and reduced shelf area. [less ▲]

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See detailCaractérisation minéralogique, géochimique et géotechnique des matières premières utilisées en poterie dans le site d’Agafay, Marrakech, Maroc.
El Boudour El Idrissi, Hicham; Daoudi, Lahcen; El Ouahabi, Meriam ULg et al

Conference (2014, April 03)

Le site potier d’Agafay est localisé à 20 km au S-W de la ville de Marrakech, à l’ouest de l’oued N’Fis. L’activité potière y a débuté par transfert du savoir-faire à partir du village de Tamsloht vers ... [more ▼]

Le site potier d’Agafay est localisé à 20 km au S-W de la ville de Marrakech, à l’ouest de l’oued N’Fis. L’activité potière y a débuté par transfert du savoir-faire à partir du village de Tamsloht vers 1940 apr. J.-C. Le site comporte environ 90 ateliers où sont actifs 240 artisans. Les principales pièces produites sont les gasriyas (i.e., plats traditionnels de couscous et de modelage de pâtes de pains) et les briques des grandes murailles traditionnelles. Les matières premières utilisées, brutes ou en mélange, sont issues des terres agricoles locales (Ag1 et Ag5) pour les gasriyas et des dépôts actuels du oued N’Fis (Ag7) pour les briques. Les problématiques rencontrées dans ce site concernent les deux types de produits, gasriyas et briques. Dans le premier cas, des grains de la chaux gonflent dans les pièces après le contact prolongé des pièces produites avec l’air. Ce gonflement engendre des décollements dans les tessons et nuit à la qualité du produit final. Dans le deuxième cas, la distribution non homogène de la chaleur à l’intérieur des fours traditionnels utilisés engendre une très grande variation de couleur dans les briques, elles sont généralement tordues et certaines fondent totalement. Notre projet vise à une caractérisation scientifique des différentes phases de fabrication afin de remédier à ces problèmes. Les résultats montrent que la composition chimique est surtout silico-alumineuse (55 à 61 % de SiO2 ; 16 à 20% d’Al2O3), la teneur en Fe2O3 se situe entre 6 et 8 %, celle de CaO ne dépasse pas 6% pour les pâtes des gasriyas et atteint 10 % pour les pâtes des briques. La teneur en carbonates mesurée par le calcimètre de Bernard varie entre 5 et 14 %. La teneur en matière organique varie entre 5 et 7,5 %. L’indice de plasticité oscille entre 16 et 17,5. Pour des teneurs en eau proches de la limite de plasticité le degré de retrait au séchage des gasriyas est de l’ordre de 5 %, il est plus élevé pour les briques (8%) ce qui nécessite une plus grande maitrise du processus de séchage pour éviter que les pièces ne se tordent pas. La granulométrie des pâtes utilisées pour les gasriyas a montré une teneur moyenne de 50 % pour les argiles, 32 % pour les limons et 18 % pour les sables. Les briques comportent une proportion égale des trois classes granulométriques. La minéralogie de l’ensemble des pâtes est formée de quartz (< 27%), plagioclase (13%), calcite (7 à 9%), dolomite (5%) et argile (50%, 34% et 34% pour Ag1, Ag5 et Ag7, respectivement). Le feldspath potassique est présent uniquement dans l’échantillon Ag7. Concernant la fraction argileuse, elle est surtout constituée d’illite pour l’ensemble des pâtes, associée à des interstratifiés irréguliers 14c-14s (13 %) pour la pâte des briques, et une teneur de 11 % de smectite pour la pâte des gasriyas (Ag5). La mesure de la vitesse sonique a montré que les pièces formées par pression aboutissent à une porosité moindre que celle des pièces produites par boudinage. La densité des pièces produites reste semblable pour les cuissons à 950°C et 1050°C. Le plus bas degré de porosité ainsi que les plus grandes valeurs de résistance mécanique à la compression ont été enregistrés sur les pièces cuites à 1050 °C. Les contraintes maximales atteintes se situent entre 51 et 59 MPa pour les gasriyas et 24,5 MPa pour les briques. Quant à la résistance mécanique à la flexion, elle varie entre 17,4 et 20,3 N/mm² pour les gasriyas et 9,4 N/mm² pour les briques. L’analyse DRX des pièces cuites à 1050 °C a montré la disparition totale des carbonates et des argiles à cette température, accompagnée de l’apparition de la géhelénite, cristobalite, anorthoclase, diopside, spinelle et hématite. A l’issue de cette étude, nous recommandons un tamisage humide à 1 mm pour réduire l’effet des gros grains de la chaux, une cuisson par palier jusqu’à 1050°C est également nécessaire pour comprendre les transformations des phases minéralogiques et vitreuses. Finalement, l’utilisation des fours équipés d’une sonde pour garantir une meilleure distribution de la chaleur. [less ▲]

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See detailMineralogical and geotechnical characterization of clays from Northern Morocco for their potential use in ceramic industry
El Ouahabi, Meriam ULg; Daoudi, Lahcen; Fagel, Nathalie ULg

in Clay Minerals (2014), 49

This study focuses on the mineralogical and geotechnical characterization of Northern Morocco clays (i.e., from Tangier and Tetouan areas) and further comparison with main clay ores used in national ... [more ▼]

This study focuses on the mineralogical and geotechnical characterization of Northern Morocco clays (i.e., from Tangier and Tetouan areas) and further comparison with main clay ores used in national ceramic (i.e., from Meknes, Fes, Salé and Safi regions). Sampled clays were analyzed by X-ray diffraction on bulk and clay (< 2 µm) fractions to identify the mineralogical assemblages of the clay outcrops. Further analyses were conducted to determine the particle size distribution (laser diffraction particle analyser), the total organic matter content (from LossOnIgnition measurements) and the Atterberg limits of the raw clays. The aims of this study were first to investigate the spatial variability of the clay samples and second to evaluate their potential application as raw materials in ceramic industry. Tetouan and Tangier clays are characterized by diversified mineralogical assemblages (in particular a variable proportion of clay, quartz and calcite) in regard with Meknes, Fes, Salé and Safi clays (high clay content, quartz and calcite). The clay fraction of Tetouan and Tangier samples is dominated by illite and kaolinite with variable contribution of chlorite, smectite and/or vermiculite. Illite is the dominant phase in Meknes, Fes, Safi and Salé clays, but is associated with kaolinite. There is no direct relationship between the mineral assemblage composition and the lithology of the series. The studied clays materials consist generally in fine particles with medium to high plasticity and low organic matter content. Taking into account mineralogy, grain-size distribution and plasticity those clays seem to be suitable as raw material for the growing Morocco ceramic industry. [less ▲]

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See detailA 3400 year lacustrine paleoseismic record from the North Anatolian Fault, Turkey: Implications for bimodal recurrence behavior
Avsar, Ulas; Hubert, Aurelia ULg; De Batist, Marc et al

in Geophysical Research Letters (2014), 41(2), 377-384

High-resolution physical, geochemical, and geochronological analyses on the sedimentary sequence of Yeniçağa Lake, located in a fault-bounded basin along the North Anatolian Fault, reveal fingerprints of ... [more ▼]

High-resolution physical, geochemical, and geochronological analyses on the sedimentary sequence of Yeniçağa Lake, located in a fault-bounded basin along the North Anatolian Fault, reveal fingerprints of paleoearthquakes. A robust sediment chronology, spanning the last 3400 years, is constructed by radiocarbon dating and time-stratigraphical correlation with the precisely dated Sofular Cave speleothem record. Yeniçağa sedimentary sequence contains 11 seismically induced event deposits characterized by siliciclastic-enriched intervals. Some of the event deposits are also associated with implications of sudden lake deepening, which may be related to coseismic subsidence. The paleoearthquake series having an average recurrence interval of ca. 260 years are interrupted by two possible seismic gaps of ca. 420 and 540 years. [less ▲]

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See detailA 3400 year lacustrine paleoseismic record from the North Anatolian Fault, Turkey: Implications for bimodal recurrence behavior
Avsar, Ulas; Hubert, Aurelia ULg; De Batist, Marc et al

in Geophysical Research Letters (2014), 41(2), 377-384

High-resolution physical, geochemical, and geochronological analyses on the sedimentary sequence of Yeniçağa Lake, located in a fault-bounded basin along the North Anatolian Fault, reveal fingerprints of ... [more ▼]

High-resolution physical, geochemical, and geochronological analyses on the sedimentary sequence of Yeniçağa Lake, located in a fault-bounded basin along the North Anatolian Fault, reveal fingerprints of paleoearthquakes. A robust sediment chronology, spanning the last 3400 years, is constructed by radiocarbon dating and time-stratigraphical correlation with the precisely dated Sofular Cave speleothem record. Yeniçağa sedimentary sequence contains 11 seismically induced event deposits characterized by siliciclastic-enriched intervals. Some of the event deposits are also associated with implications of sudden lake deepening, which may be related to coseismic subsidence. The paleoearthquake series having an average recurrence interval of ca. 260 years are interrupted by two possible seismic gaps of ca. 420 and 540 years. [less ▲]

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See detailPotentiality of clay raw materials from northern Morocco in ceramic industry: Tetouan and Meknes areas
El Ouahabi, Meriam ULg; Daoudi, Lahcen; De Vleeschouwer, François et al

in Journal of Minerals and Materials Characterization and Engineering (2014)

This study aims at evaluating the potential suitability of Tetouan and Meknes (central Morocco) clay material as raw materials in various ceramic applications by investigating their textural, chemical ... [more ▼]

This study aims at evaluating the potential suitability of Tetouan and Meknes (central Morocco) clay material as raw materials in various ceramic applications by investigating their textural, chemical, thermal and firing characteristics. Textural properties were identified by specific surface area, cation exchange capacity (CEC) and bulk density (ρs). Chemical and thermal properties were assessed using XRF and TG/DTA techniques, respectively. Firing characteristics at temperatures from 800°C to 1100°C were determined by linear firing shrinkage, loss on weight and water absorption capacity. The Meknes clays are characterised by medium cation exchange capacity (CEC) and specific surface area (SSA) values due to their moderate smectite content. The Tetouan clays have medium to low CEC and medium SSA values. The main oxides in the clayey samples are SiO2 (35 – 54.3 wt.%), Al2O3 (20.6 – 43.9 wt.%), and Fe2O3 (9.7 – 22.4 wt.%). The amount of CaO in Meknes clays ranges from 8 to 12 wt.%, whereas CaO is only present in some Tetouan clay (TE4, TE7, TN4 and TN5). A significant densification of ceramic behaviour could be noticed for most of Tetouan clays at firing temperatures above 1000°C. Meknes clays show earlier densification from 800 °C. The chemical, textural and ceramic properties of Tetouan and Meknes clays indicate their suitability as raw materials for the production of structural ceramics. The high amount of Fe2O3 in all clays makes them inappropriate in fine ceramics. [less ▲]

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See detailCharacterization of clay deposits of Nanga-Eboko (Central Cameroon): Suitability in the production of building materials
Nzeukou Nzeugang, A.; Medjo Eko, R.; Fagel, Nathalie ULg et al

in Clay Minerals (2013), 48(4), 655-662

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See detailHolocene dust record in a NW European peat bog: A multiproxy approach
Allan, Mouhamd ULg; LE ROUX, gael; VERHEYDEN, SOPHIE et al

Conference (2013, August 28)

Dust deposition in southern Belgium is estimated from the geochemical signature of an ombrotrophic bog. The analyses of Rare Earth Elements (REE) and lithogenic element concentrations as well as Nd ... [more ▼]

Dust deposition in southern Belgium is estimated from the geochemical signature of an ombrotrophic bog. The analyses of Rare Earth Elements (REE) and lithogenic element concentrations as well as Nd isotopes were performed by HR-ICP-MS and MC-ICP-MS respectively, in a  6 m peat section representing 5300 years, from 30 BC to 5300 BC dated by the 14C method. REE concentration variations in peat samples were used as a dust proxy and the Nd isotopes to trace the sources. Peat humification and testate amoebae were used to evaluate hydroclimatic conditions. The range of dust deposition varied from 0.03 to 4 g m-2 yr-1. The highest dust fluxes were observed from 800 to 600 BC, and from 3200 to 2800 BC and correspond to cold periods. The Nd values show large variability, between -5 and –13, identifying three major sources of dust: local soils, distal volcanic and desert particles. By comparing our results with the dust recorded in other peat bogs and ice cores from different latitudes, we evidence that the Misten peat is a valid archive for dust deposition. [less ▲]

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See detailDust historical record in ombrotrophic peat: The case study of a NW European bog
Allan, Mouhamd ULg; Fagel, Nathalie ULg; Le Roux, Gael et al

Poster (2013, May 16)

Ombrotrophic peatlands are unique environmental archives of natural and anthropogenic atmospheric dust deposition because their surface layers are exclusively fed by atmospheric inputs. Lead (Pb) isotopes ... [more ▼]

Ombrotrophic peatlands are unique environmental archives of natural and anthropogenic atmospheric dust deposition because their surface layers are exclusively fed by atmospheric inputs. Lead (Pb) isotopes have been often used to evidence any anthropogenic influence in peat, but they only record trace metal pollution. Another radiogenic isotope, the Neodymium (Nd), could be also use to discriminate the sources of dust in peat bogs. Dust fluxes were investigated over the last 2500 years in the Misten peat bog in Eastern Belgium. Our aims were to use Nd isotope signature to decipher between local and distal dust supplies, the Pb isotopes to trace the antropogenic influences. To address these aims we analyzed REE and lithogenic element analyses, as well as the Nd and Pb isotopes, using HR-ICP-MS and MC-ICP-MS, respectively in peat layers dated by 210Pb and 14C. Changes in REE concentration variations in peat samples are correlated with Ti, Al, and Zr that are lithogenic conservative elements, suggesting that REE are immobile in the studied peat bogs and can be used as tracers of dust deposition. Dust fluxes show pronounced increase at BC300, AD600, 1000AD, 1200AD and from 1700AD, recording either influence of human activities (regional erosion due to forest clearing and soil cultivation activities) or local and regional climate changes. Lead enrichments reveal strong human impact over the last 300 years. Lead isotope signatures are consistent with local and regional contamination by coal combustion and smelting activities. Neodymium isotopes allow to identify three periods characterised by dominant-distal sources (at 320AD, 1000 AD and 1700AD). Those periods are consistent with local wetter intervals as indicated by lower humification degree. Local erosion prevails durier drier (higher humification) intervals (-100AD, 600AD). On a global scale more distal supplies are driven during colder periods, in particular Oort and Maunder minima, confirming the hypothesis that cold climate conditions favor distal supplies. Combining geochemical elementary content and isotope data in ombrotrophic peat allows to decipher between dust flux changes related to human and climate forcing. [less ▲]

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See detailDeciphering human-climate interactions in ombrotrophic peat record : REE, Nd and Pb isotope signatures of dust supplies over the last 2500 years (Misten bog, Belgium)
Fagel, Nathalie ULg; Allan, Mouhamd ULg; le roux, Gael et al

Poster (2013, April 08)

A core of 173 cm of ombrotrophic Misten peat bog from the Hautes-Fagnes Plateau in Eastern Belgium provides a record of Rare Earth Elements (REE) deposition allowing to trace dust fluxes in West Europe ... [more ▼]

A core of 173 cm of ombrotrophic Misten peat bog from the Hautes-Fagnes Plateau in Eastern Belgium provides a record of Rare Earth Elements (REE) deposition allowing to trace dust fluxes in West Europe during the historical record (last 2500 years). REE and lithogenic element analyses, as well as the Nd isotopes, were performed by HR-ICP-MS and MC-ICP-MS, respectively in peat layers dated by 210Pb and 14C. The parallel variations of REE concentration with lithogenic conservative elements confirms that REE are immobile in the studied peat bog and can be used as tracers of dust deposition. Dust fluxes show pronounced increase at BC300, AD600, 1000AD,1200AD and from 1700AD, recording either influence of human activities (regional erosion due to forest clearing and soil cultivation activities) or local and regional climate changes. Using Nd isotope allows to decipher between local and distal causes. The ENd variability (-13 to -9) is interpreted by a mixing between dust sources fromlocal soils and desert particles. Three periods characterised by dominant-distal sources (at 320AD, 1000 AD and 1700AD) are consistent with local wetter intervals as indicated by lower humi[U+FB01]cation degree. Local erosion prevails durier drier (higher humification) intervals (-100AD, 600AD). On a global scale more distal supplies are driven during colder periods, in particular Oort and Maunder minima. Combining geochemical elementary content and isotope data in ombrotrophic peat allows to decipher between dust flux changes related to human and climate forcing. [less ▲]

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See detailReconstructing historical atmospheric mercury deposition in Western Europe using: Misten peat bog cores, Belgium
Allan, Mouhamd ULg; le roux, gael; E. Sonke, Jeroen et al

in Science of the Total Environment (2013), 442

Four sediment cores were collected in 2008 from the Misten ombrotrophic peat bog in the Northern part of the Hautes Fagnes Plateau in Belgium. Total mercury (Hg) concentrations were analyzed to ... [more ▼]

Four sediment cores were collected in 2008 from the Misten ombrotrophic peat bog in the Northern part of the Hautes Fagnes Plateau in Belgium. Total mercury (Hg) concentrations were analyzed to investigate the intra-site variability in atmospheric Hg deposition over the past 1500 years. Mercury concentrations in the four cores ranged from 16 to 1100 μg kg− 1, with the maxima between 840 and 1100 μg kg− 1. A chronological framework was established using radiometric 210Pb and 14C dating of two cores (M1 and M4). Pollen horizons from these two cores were correlated with data from two additional cores, providing a consistent dating framework between all the sites. There was good agreement between atmospheric Hg accumulation rates in the four cores over time based on precise age dating and pollen chronosequences. The average Hg accumulation rate before the influence of human activities (from 500 to 1300 AD) was 1.8 ± 1 μg m− 2 y− 1 (2SD). Maximum Hg accumulation rates ranged from 90 to 200 μg m− 2 y− 1 between 1930 and 1980 AD. During the European–North American Industrial Revolution, the mean Hg accumulation rate exceeded the pre-Industrial values by a factor of 63. Based on comparisons with historical records of anthropogenic activities in Europe and Belgium, the predominant regional anthropogenic sources of Hg during and after the Industrial Revolution were coal burning and smelter Hg emissions. Mercury accumulation rates and chronologies in the Misten cores were consistent with those reported for other European peat records. [less ▲]

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See detailMineralogy and physico-chemical properties of alluvial clays from
Nzeugang Nzeukou; Fagel, Nathalie ULg; Njoya, André et al

in Applied Clay Science (2013), 83-84

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See detailHydrological instability during the Last Interglacial in central Asia: a new diatom oxygen isotope record from Lake Baikal
Mackay, Anson; Swann, Georges; Fagel, Nathalie ULg et al

in Quaternary Science Reviews (2013), 66

Last Interglacial variability is commonly used as an analogue for variability in a future, warmer world. Pervasive cycles are increasingly apparent in Last Interglacial archives, although studies in ... [more ▼]

Last Interglacial variability is commonly used as an analogue for variability in a future, warmer world. Pervasive cycles are increasingly apparent in Last Interglacial archives, although studies in continental regions are under-represented. Here we provide a new isotopic record of diatom silica (d18Odiatom) spanning c. 127.5e115 ka BP from Lake Baikal in central Asia. Peak rain-fed discharge occurred c. 125.4 ka BP, shortly after July insolation maximum and initiation of Siberian soil development. Between 127 and 119.7 ka BP there are six marked fluctuations in d18Odiatom values, with a pacing of approximately 1.26 0.3 ka, similar to fluctuations of within lake productivity. Fluctuations in d18Odiatom values show good agreement with patterns in Atlantic meridional overturning circulation (AMOC), supporting hypothesis of strong teleconnections via theWesterlies between the North Atlantic and central Asia. Two periods of low d18Odiatom values are especially notable. The earliest between c. 126.5 and 126 ka BP is concurrent with the final stages of the Heinrich 11. The second between 120.5 and 119.7 ka BP is also concurrent with an increase in ice-rafted debris in the North Atlantic. Aquatic productivity in Lake Baikal increased between 119.7 and 117.4 ka BP before declining to the top of the record (115 ka BP) concomitant with a shift to predominately cool steppe catchment vegetation. However, isotopic composition of discharge into Lake Baikal provides evidence for strong penetration of Westerlies into central Asia during the latter stages of the Last Interglacial. Variability in d18Odiatom values was compared between the Last Interglacial and the Holocene. Millennial-scale variability was significantly more stable during the Last Interglacial, possibly linked to diminished influence of freshwater discharge on AMOC during periods of higher, global mean temperatures. [less ▲]

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See detailHydrological instability during the Last Interglacial in central Asia: a new diatom oxygen isotope record from Lake Baikal
Mackay, Anson; Swann, Georges; Fagel, Nathalie ULg et al

in Quaternary Science Reviews (2013), 66

Last Interglacial variability is commonly used as an analogue for variability in a future, warmer world. Pervasive cycles are increasingly apparent in Last Interglacial archives, although studies in ... [more ▼]

Last Interglacial variability is commonly used as an analogue for variability in a future, warmer world. Pervasive cycles are increasingly apparent in Last Interglacial archives, although studies in continental regions are under-represented. Here we provide a new isotopic record of diatom silica (d18Odiatom) spanning c. 127.5e115 ka BP from Lake Baikal in central Asia. Peak rain-fed discharge occurred c. 125.4 ka BP, shortly after July insolation maximum and initiation of Siberian soil development. Between 127 and 119.7 ka BP there are six marked fluctuations in d18Odiatom values, with a pacing of approximately 1.26 0.3 ka, similar to fluctuations of within lake productivity. Fluctuations in d18Odiatom values show good agreement with patterns in Atlantic meridional overturning circulation (AMOC), supporting hypothesis of strong teleconnections via theWesterlies between the North Atlantic and central Asia. Two periods of low d18Odiatom values are especially notable. The earliest between c. 126.5 and 126 ka BP is concurrent with the final stages of the Heinrich 11. The second between 120.5 and 119.7 ka BP is also concurrent with an increase in ice-rafted debris in the North Atlantic. Aquatic productivity in Lake Baikal increased between 119.7 and 117.4 ka BP before declining to the top of the record (115 ka BP) concomitant with a shift to predominately cool steppe catchment vegetation. However, isotopic composition of discharge into Lake Baikal provides evidence for strong penetration of Westerlies into central Asia during the latter stages of the Last Interglacial. Variability in d18Odiatom values was compared between the Last Interglacial and the Holocene. Millennial-scale variability was significantly more stable during the Last Interglacial, possibly linked to diminished influence of freshwater discharge on AMOC during periods of higher, global mean temperatures. [less ▲]

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