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  • The tephrostratigraphy of core LC21. 5 cm low resolution samples on left of diagram with tephra counts represented by blue bars (capped at counts >3000 shards per gram). Results of high resolution re-sampling at 1 cm resolution on the right of the diagram. Samples extracted and analysed for geochemistry are labelled with red lines and names, with the extent of visible tephras denoted by red boxes. The visual extents of sapropels (S1, S3, S4 and S5) are indicated by the grey areas and respective labels (e.g. S1). Core depth below the sea floor in meters is shown on the left of the diagram. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.) ... Age model for LC21 (after Grant et al., 2012) constructed by correlating the δ18Oruber isotope stratigraphy to the Soreq cave (Bar-Matthews et al., 2000). Black crosses indicate radiocarbon dates while red crosses indicate tie-points between the isotope stratigraphies. The error range of the age model is shown by the orange band. Tephra layers are shown by vertical black lines, sapropels are shown as grey vertical bands and labelled S1, S3, S4a, b and S5. The Minoan (LC21 0.940) and Campanian Ignimbrite (LC21 4.925) tephras were used in the construction of the age model and are shown by dotted vertical lines. Dates for the tephras, as defined from this age model (with the exception of LC21 0.940 and 4.925), are given in Table 1. Tephra layers older than the period represented by the age model are shown here in blue. The reader is referred to Grant et al. (2012) for details of the construction of the age model (including the calculations of sedimentation rates) through the correlation of the LC21 isotope stratigraphy with that of Soreq cave. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.) ... Total Alkalis vs Silica diagrams (Le Bas, 1986) for the tephra samples described in LC21, arranged in stratigraphic order and divided for clarity into A) samples above sapropel 3, B) samples below sapropel 3, C) Al2O3 vs FeOt plot (after MacDonald, 1974) for sample LC21 (10.345) showing 5 shards which plot in the Pantellerite field. These samples from core LC21 are named with the depth in the core.
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  • Center for Environmental Sciences and Education/Quaternary Sciences Program, Northern Arizona University, Flagstaff, AZ 86011-5694, USA... Age model for Tustumena Lake (02-TL-03) and Paradox Lake (98-PL-01) cores. Solid curves were calculated based on the spline-fit routine of Heegaard et al. (2005), with k (number of splines used in the cubic smooth spline regression) set at 10 for both models); dashed curves are 95% confidence intervals used to estimate age errors for each tephra. Vertical dashes are median ages of calibrated-age probability distributions, and bars show 2σ calibrated age range. Two rejected ages >20 ka are not shown. See Table 1 for ages. ... Number of tephra in Paradox Lake per 200-yr interval and volcanic sulfate (ppb) from the GISP2 ice core, Greenland (Zielinski et al., 1996). Ages of individual tephra shown in Appendix A. ... Lacustrine sediment... Stratigraphy and magnetic susceptibility (MS) of (A) Tustumena Lake core (02-TL-03) and (B) Paradox Lake core (98-PL-01). Tustumena Lake surface core designations (02-TL-03a, 02-TL-03b, and 02-TL-03fc) are indicated by letters a, b and fc. Paradox Lake surface core designations (02-PL-01a, 02-PL-01b, and 02-PL-01d) are indicated by letters a, b, and d. Offsets for plotting of surface core MS (×10−5 SI): 02-TL-03a=250; 02-TL-03b=400; 02-PL-01b=400; 02-PL-01d=700. Surface core depths corrected for compression (02-TL-03a=1.75 cm; 02-TL-03b=1.65 cm). ... (A) Bathymetry of Tustumena Lake, showing core site (02-TL-03). (B) Bathymetry of Paradox Lake, showing core site (98-PL-01). Refer to Figure 1 for lake locations. ... Photomicrographs of sediment grain mounts with graduated abundance rankings, showing tephra-glass pumice, shard, and crystal morphologies (see de Fontaine, 2003, for further explanation). (A) trace: 1–5%, (B) prevalent: 5–25%, (C) abundant: 25–50%, (D) pure: >50%, (E) pumice (p), (F) shard (s), and (G) glass-coated crystal (x); p — pumice fragments. Photomicrographs are of Tustumena Lake core 02-TL-03 basal tephra at (A) 383.2, (B) 381.5, (C) 381.9, (D, E, F) 382.3, and (G) 382.7 cm depth. ... Late Quaternary
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  • Lithological units of Core PRD05 ... Distribution of selected foraminiferal species (with abundance >1% of all foraminifers) and ecological groups in Core PRD05. Foraminiferal abundance expressed as number of specimens per 100g dry sediment. Note different scales. ... Distribution of selected ostracod species (with abundance >1% of all ostracods) and ecological groups in Core PRD05. Ostracod abundance expressed as number of specimens per 100g dry sediment. Note different scales. ... Late Quaternary... Location of the studied Core PRD05. ... Lithological units of Core PRD05 with 14C dates and weight percentages of sediments with a grain size <63μm.
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  • Abstract: An astronomically tuned late Quaternary planktic foraminiferal delta18O record of Site MD972142 (12°41.33'N, 119°27.90'E; 1557 m water depth) in the southeastern South China Sea was established. The difference in delta18O between MD972142 and ODP792 of the Sulu Sea is regarded as a maritime proxy of the summer monsoon intensity over the South China Sea and Southeast Asia. The profile of this maritime proxy matches well with the summer monsoon index obtained from the terrestrial record of Louchuan, central Chinese Loess Plateau. The amplified planktic delta18O signals of the South China Sea relative to the Sulu Sea record are partly caused by the changing intensities of the East Asian Monsoons at the glacial-interglacial time-scale throughout the late Quaternary. Category: geoscientificInformation Source: Supplement to: Wei, Kuo-Yen; Chiu, Tzu-Chien; Chen, Yue-Gau (2003): Toward establishing a maritime proxy record of the East Asian summer monsoons for the late Quaternary. Marine Geology, 201(1-3), 67-79, https://doi.org/10.1016/S0025-3227(03)00209-3 Supplemental Information: Not Availble Coverage: EVENT LABEL: (MD972142) * LATITUDE: 12.685000 * LONGITUDE: 119.465000 * Recovery: 35.91 m * CAMPAIGN: MD106 * BASIS: Marion Dufresne (1995) * METHOD/DEVICE: Calypso Corer
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  • Stages of inundation of the central Sunda Shelf. Shape and position of the certain morphological structures (Proto-Kapuas and Proto-Lupar Rivers, Natuna Islands, paleo-coastline) is partly hypothetical. Selected stages: (a) 30kyr—progradation of clinoforms and isolated sediment bodies (not shown). (b) 21calkyr bp—widespread exposure. Sediment bypassing through the central valley and deposition in the shoreline area. (c) 15kyrcal. bp—drowning and fill of the lowermost river course. Sedimentation focussed within the drowned part of the valley. Change from deltaic to estuarine conditions. (d) 14calkyr bp—rapid retreat of the river mouth and drowning of the valley during heavily accelerated sea-level rise. Sea-level approximately reached the margin of the interfluve plain (−70 m modern water depth in average) and a network of distributary channels replaced the former drainage system. (e) 13calkyr bp—complete submergence of the area. Valleys remain as depressions on the seafloor from this time onward and the shelf starved of terrigenous sediments. ... Schematised cross-section along the transect showing the depositional units and major surfaces (as defined in the text) based on the core data. For legend see Fig. 4. For abbreviations see Figs. 2 and 8. TST: terrestrial (black), mangrove (plant symbols), marine (lined; delta front to inner shelf facies). ... (a) Lithology of sediment cores. Depth in meters below sea surface (mbss). Core length is half of this scale. In the middle part of the transect, two different elevations are cored (inside the central valley and on the adjacent plains of the seafloor). Note that (i) some cores represent a group of cores containing the same facies succession merged for simplification and (ii) the distance between the cores is not equidistant in reality (cf. Fig. 1). (b) Correlation by discrimination of environmental units. The cores are normalized on the subaerial surface, which formed during the exposure around the last glacial maximum. ... Study area (a) and SO-115 transect on the Sunda Shelf (b); solid line: the transect presented here; (c) locations of sediment cores (black circles) with core numbers as used in Fig. 4. Position of the seismic records shown in Fig. 3 (grey rhombs): ‘x’ refers to profiles a and b, ‘o’ to profile c in Fig. 3. A-V, NS-V, PK-V, PL-V indicate the positions of the paleo-valleys of the Anambas, North Sunda, Kapuas and Lupar rivers (after Haile, 1969). ... Seismic profiles showing typical patterns of depositional units and erosional surfaces. SPGM and SLGM indicate the (subaerial) surfaces during the penultimate and the last glacial maximum; ts=transgressive surface, rs=ravinement surface (with indices 1–3 as used in the text). Arrows mark the positions of three cores. ... Late Quaternary
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  • Abundance pattern of the sea-ice indicators Fragilariopsis curta and F. cylindrus in sediment cores PS2305-6, PS2276-4 and PS1768-8 from a W–E transect. For location of cores, see Fig. 2. ... Abundance pattern of the sea-ice indicators Fragilariopsis curta, F. cylindrus and F. obliquecostata in six sediment cores from a S–N transect across the Southern Ocean and interpretation of sea-ice extent during glacial maxima in MIS 2 and 4. For location of cores, see Fig. 2. ... Locations of sediment trap moorings and sediment cores in the Atlantic sector of the Southern Ocean. The schematic representation of frontal zones and average sea-ice distribution is according to Naval Oceanography Command Detachment (1985), Peterson and Whitworth (1989), Peterson and Stramma (1991), Orsi (1993). ... sediment trap... Combined relative abundance of Fragilariopsis curta and Fragilariopsis cylindrus in surface sediments from the Atlantic and eastern Indian sector of the Southern Ocean. For references for the location of oceanographic fronts and sea-ice distribution, see Fig. 2.
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  • Stratigraphic zones in the Kirisjes Pond sediment core, based on Verleyen et al. (2004a). ... δ13Corg vs. C/N of representative samples in the marine and freshwater zones of the Kirisjes Pond sediment core compared with samples between 156 and 158cm (KPI, KPII). ... HPLC–MS peak assignments from Kirisjes Pond sediment extracts. ... MIS 3 marine transgression in the Larsemann Hills based on the presence of marine sediments in Kirisjes Pond compared with ice-volume-equivalent sea level derived from the continental-margin earth model E1 presented in Lambeck et al. (2002, Figure 11), and the Vostok Ice Core d180atm data derived from the World Data Centre for Paleoclimatology and are presented on the GT4 timescale (Petit et al., 1999) and used as a proxy for mean surface air temperature over time. The radiocarbon dates of late Quaternary raised beach deposits in the Syowa Oasis around Lützow-Holm Bay are based on incorporated marine fossils, with data compiled by Miura et al. (1998a). These are presented as uncalibrated ages. MIS 1 marine transgressions in the Larsemann Hills are based on data presented in Verleyen et al. (2005). ... Diatom species composition of sediments between 146 and 158cm in the Kirisjes Pond core (%). Only species recorded at >2% relative abundance are included.
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  • Vertical variations of coarse fractions (%), calcium carbonate (%), and organic geochemical components in core YSDP 103 ... Average sedimentation rates (m/kyr) of core YSDP 103 on the basis of calendar ages (left) and lithology of the core (M=mud, Gs=gravelly sand, and R=rock fragments) with 7 calendar ages (right). ... Oxygen and carbon isotopes (‰) of benthic foraminifer (Cibicides lobatulus) in core YSDP 103 ... AMS 14C and calendar ages in core YSDP 103 ... Vertical distributions of 30 dominant benthic foraminiferal species (%) in core YSDP 103. The order of species follows relative abundances (%).
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  • Variations of Ta/Sc with depth in the five studied sediment cores (enclosed core names in Fig. 2; closed circles in Fig. 1). Gray zones highlight visible tephra horizons in the cores: the AT, B–J, DKP, and Aso-4 tephra horizons as indicated in Fig. 2. Peaks in Ta/Sc indicate the presence of an alkaline tephra component, and the codes next to each peak indicate the core name and the number of the peak within the core. The two arrows in GH86-2-N indicate dips in Ta/Sc, suggesting the presence of a non-alkaline tephra component. Parentheses show identification and regional correlation of tephra and cryptotephra horizons. Gray zones show tephra horizons visible to the naked eye. ... Correlation between reported tephra and identified cryptotephra and speciation of some thinly laminated (TL) layer in the four studied cores (enclosed name cores), based on TL layer profiles and identified tephra layers. The gray bands indicate the dark colored TL layers. The vertical scale for the four studied cores (enclosed core name) is based on the linear interpolated ages using the AT (29.4ka) and the Aso-4 (87ka) tephra positions or the linear interpolated and extrapolated ages using the AT and the base of TL-14 (51.5ka) positions (Tada et al., 1999). TL-14 layers in the northern Japan Sea/East Sea are frequently associated with the B–J tephra (48–51ka; Ikehara et al., 2004). ... Refractive index of glass shards in the cryptotephra positions from core GH86-2-N. ... Photo-micrographs of typical tephra-derived grains from the six Ta/Sc-peak-layers in core GH89-2-28. ... Late Quaternary... The depth profiles and bulk data of trace-element analysis from five marine sediments, using INAA.
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  • Major and minor elements in bulk sediments of core MD03-2603, profiles vs. Al and vs.Ti, plotted inst age (0–491ka BP); marine isotope stages (MIS) are reported on top. a. Profiles of Ba/Al (above) and Ba/Ti (below), used as a reference for constraining the core chronology (see Fig. 3). b. Profiles of Mn/Al (above) and Mn/Ti (below). c. Profiles of Mo/Al (above) and Mo/Ti (below). Dash/thin lines: 5-point running mean (for Mo/Al and Mo/Ti). d. Profiles of Fe/Al (lighter) and Fe/Ti (darker). e. Profiles of Ni/Al (lighter) and Ni/Ti (darker). f. Profiles of Zn/Al (lighter) and Zn/Ti (darker). Thicker lines: 5-point running mean of each parameter. Gray shaded areas: interglacial marine isotope stages (MIS 1, 3, 5, 7, 9, 11, 13). ... Age model of core MD03-2603, based on the comparison of: a. the LR04 δ18O marine benthic stack (‰ VPDB; Lisiecki and Raymo, 2005), to b. down-core logs of reflectance and Ba/Al atomic ratio. Correlation is feasible back to 491ka BP. c. Diatom biostratigraphy based on four species, recognized as biomarkers, supports the core chronology. LOD, Last Occurrence Datum (or appearance) of the extinct diatom species; LCO, Last Common Occurrence of the extinct diatom species. Eucampia antarctica is a biostratigraphic marker for the LGM (Burckle and Burak, 1996; Gersonde et al., 2005). AMS 14C date: indicated by an arrow at cm 4–5. d. Sedimentation rate (S) obtained by the age model. Light gray line: depth vs. S, calculated between 43 age control-points; thick gray line: depth vs. age. The average S is also shown (6.8cmka−1). ... sedimentation processes... a. Ba/Al profile in core MD03-2603, plotted against age, used for constraining the core chronology, in comparison to: b. EPICA Dome C ice core high-resolution deuterium profile, and c. temperature change, both on EDC3 timescale (Jouzel et al., 2007). EPICA data are shifted by 3ka towards younger ages, in analogy to previous work (Parrenin et al., 2007). We show the correspondence existing between each one of the Ba/Al peaks of the studied sediment sequence and the successive MIS (1–13) as recorded in the EPICA Dome C isotopic record, back to the age of 491ka. d. Age profile of Mn/Al, and e. Mo/Al (dashed line: 5-point running mean), in comparison to: f. high-resolution record of aeolian dust fine particle percentage (FPP), and g. dust mass concentration, both determined by laser particle counter (Lambert et al., 2008). The absence of correspondence between Mn/Al peaks and dust mass concentration for MIS 8, 10 and 12 is interpreted as a diagenetic effect, affecting the Mo/Al profile to a lesser extent. ... a. LR04 δ18O benthic stack (‰ VPDB) for 43 selected tie-points vs. Ba/Al (black dots) and Ba/Ti (open triangles) atomic ratios in bulk sediments of core MD03-2603. Values are inversely correlated: Pearson's correlation coefficients (R2) vs. δ18O are with pcore record of Ba/Al and Ba/Ti, converted to the age scale, de-trending and evenly sampling the series at 1ka, a significant correlation to the δ18O benthic stack record still exists.. ... Down-core profile of lithological characteristics, sediment structures, reflectance and volume-specific magnetic susceptibility (κ, solid lines: 5-point running mean, i.e. average of 10cm), diatom census counts (given as valvesg−1 dry sediment), relative percentages of diatom species encountered in core MD03-2603. Diatoms having similar ecological preferences (sea-ice: Gersonde and Zielinski, 2000; Armand et al., 2005; water stratification: Crosta et al., 1997; Leventer et al., 2002; unconsolidated sea-ice: Leventer et al., 1996; Armand et al., 2005) are joined as cumulative percentage. Gray shaded areas from reflectance to diatom census profiles point to coincidence between highs in reflectance and in diatom content. Depths in centimeters below the seafloor.
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