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  • Spatial (core transect across the system) and time (isotopic stages) variation of the bulk sedimentation rate, mean carbonate content, and derived terrigenous and carbonate sedimentation rates. Cores location in Fig. 2. ... Quaternary... Core location ... Lithology, CaCO3 records and correlation of the sediment cores across the Sao Tomé system (core location in Fig. 2). Lithologic sketch drawn from visual core description: 1) carbonate-rich mud, 2) clayey silt, 3) silt, 4) fine sand, 5) coarse sand. Tie points (fine line) indicate peak-to-peak correlations among the cores from the CaCO3 records. The limits of the isotopic stages defined in cores KS8813 and KS8817 are reported in plain lines. Data from the pilot cores (KP8813 and KP8817) are plotted separately above the Kullenberg cores (KS). ... Spatial (average by core) and temporal (average for glacial and interglacial sediments) variability of the mineral assemblages (untreated sediment cores. Data in Table 5. ... sediment... CaCO3 %, and bulk, carbonate and terrigenous sedimentation rates
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  • Correlations of chemical index of alteration (CIA) with K/Na ratio and Sr/Ba ratio in the core sediments. The strong correlation between K/Na ratio and CIA demonstrates their uses as proxy for identifying degree of chemical weathering. ... A–CN–K diagrams for sediment averages from Cores G3, DY and PD and comparisons of the chemical index of alteration (CIA) with those of the modern Changjiang, Huanghe and loess sediments. ... Quaternary... The averages of mean grain size (Mz) compositions and elemental concentrations of the sediments of Cores G3, DY and PD ... Comparisons of elemental ratios in the sediments between Cores G3, DY and PD and the modern Changjiang and Huanghe Rivers (Unit of CaCO3: weight%) ... A–CN–K (Al2O3–(CaO*+Na2O)–K2O) diagrams for the sediments from Cores G3, DY and PD. Note the variable distribution patterns of different core samples. Kao: kaolinite; Gi: gibbsite; Chl: chlorite; Sm: smectite; Ill: illite; Pl: plagioclase; Ksp: potassium feldspar. The A–CN–K diagram was modified after Nesbitt and Young (1982, 1984).
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  • Quaternary... Late... sediments... sediment... Sediments
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  • Correlation of climate-proxy records of cores NIOP469 and 74KL. Data of core 74KL is taken from Sirocko et al. (1993, 1996). (A) Sr/Ca ratio in bulk sediment fraction, NIOP469. (B) Mg/Al ratio in bulk sediment fraction, NIOP469; Dolomite content in terrigenous fraction >2μm, 74KL. (C) Logarithm of end-member ratio EM2:EM3 in siliciclastic fraction, NIOP469; Terrigenous sediment content, 74KL. (D) Neogloboquadrina dutertrei δ18O, NIOP469; Globigerinoides ruber δ18O, 74KL. ... Sediment composition in core NIOP469. (A) Neogloboquadrina dutertrei δ18O. (B) carbonate content. (C) Sr/Ca ratio in bulk sediment fraction. (D) Mg/Al ratio in bulk sediment fraction. (E) Logarithm of end-member ratio EM2:EM3 in siliciclastic fraction. ... Turbidite distribution and thickness in cores NIOP468–NIOP472. The division of core NIOP469 into chronostratigraphic units is based on 14C datings; subdivision of the other cores is based on correlation of various compositional parameters (δ18O, Ca content, grain-size distribution; Figs. 3 and 7), determined on intercalated hemipelagic muds, with the records of core NIOP469 (see text for discussion). Turbidite frequency and sedimentation rate are indicated for each chronostratigraphic unit. ... Sediment cores ... Mixing model of the Makran continental slope sediment samples. (A) All 384 sediment samples. (B) Binary mixing of EM1 and EM2 prevails in the turbiditic sediments (n=65) in cores NIOP469 and NIOP472. (C) Binary mixing of EM2 and EM3 prevails in the hemipelagic sediments (n=319) in cores NIOP468–NIOP472.
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  • Sediment drift... Shaded and contoured (interval of 200m) bathymetric map of the south Aegean Sea. The thick red line indicates the isobath of 100m. The top left shaded bathymetric map of the entire Aegean Sea shows the surface circulation (grey arrows) and areas of dense water formation (black stars) (adapted from Canals et al., 2009). The top right bathymetric map shows the location of seismic lines and analysed sediment cores. White circles represent the AEG cores, whereas black circles represent the DEH cores. AMC: Asia Minor Current. ... Late Quaternary Eastern Mediterranean Transient events... Bathymetric map showing the distribution of the identified sedimentary facies in the southwest Aegean Sea. White bullets indicate the sampling locations of analysed sediment cores. White and black circles represent the location of the AEG and DEH sediment cores, respectively. ... Identified sedimentary facies in all analysed cores together with stratigraphic correlation. BC1–9: bottom-current related beds. The location of the cores is shown in Fig. 5. ... Sediment core photographs illustrating examples of the identified sedimentary facies. The location of the cores is shown in Fig. 5. ... Age estimation of each bottom-current related bed (BC1–9) in comparison with the NGRIP oxygen isotope curve (NGRIP Members, 2004) and the sea-level fluctuation curve. Little stars indicate actual AMS 14C ages. Open lines indicate uncertainty in the age prediction. The location of the cores is shown in Fig. 5.
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  • Results of the radiocarbon dating of core from Dabaka swamp. ... Lithostratigraphical sediment description of the core from Dabaka swamp, Assam. ... Quaternary Palynology Division, Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow-226007, Uttar Pradesh, India... Palynoassemblage recovered from sediments of Chayagaon reserve forest and swamp. 1. Emblica officinalis, 2. Ilex sulcata, 3. Syzygium cumini, 4. Lagerstroemia parviflora, 5. Elaeocarpus rugosus, 6. Shorea robusta, 7. Terminalia bellirica, 8. Salmalia malabaricum, 9. Artocarpus chaplasha, 10. Mimusops elengi, 11. Lannea coromandelica, 12. Symplocos racemosa, 13. Acacia catechu, 14. Areca catechu, 15. Melastoma malabathricum, 16. Ligustrum compactum, 17. Non-cereal (Poaceae), 18. Cereal (Poaceae), 19. Tubuliflorae, 20. Xanthium strumarium, 21. Chenopodiaceae, 22. Caryophyllaceae, 23. Polygonum serrulatum, 24. Impatiens balsamina, 25. Onagraceae, 26. Cyperaceae, 27. Nymphaea nouchali, 28. Pinus khasiana, 29. Alnus sp., 30. Pteris sp (trilete spore), 31 & 32. Trilete spore (unknown), 33. Biological degradation of trilete spore, 34. Woodwardia sp. (monolete spore), 35. Davallia sp. (monolete spore), 36 & 37. Partial degradation in Woodwardia spore, 38. Botryococcus sp., 39. Pediastrum sp., 40. Tetraploa sp., 41. Diplodia sp., 42. Ascospore of Cookeina, 43. Alternaria sp., 44. Glomus sp., 45. Microthyriaceae, 46. Trachiedal pits, 47. Parenchymatous tissue.
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  • Depth distribution of pH, EC, CaCO3, OC, particle size distribution and textural class of the Bhognipur core. ... The XRD analysis of core sediments from IITK core shows dominance of mica in the silt (50–2μm) and coarse clay (2–0.2μm) fractions that also contain mixed-layer minerals, smectite, vermiculite, HIV, PCh, kaolin, feldspar and quartz (see Figs. 1–3 in the supplementary material). The fine clay fractions (<0.2μm) are dominated by mica and smectite along with vermiculite, HIV, PCh and kaolin. The smectite is predominantly LCS and dioctahedral in nature in fine clay fraction but silt and coarse clay fractions are dominantly HCS. The collapsing characteristics of K-saturated fine clay on heating from 110°C to 550°C indicate that most of the LCS has hydroxy-interlayering (Harward et al., 1969).... Identification key for the clay minerals in IITK and Bhognipur cores, Ganga–Yamuna interfluve, India. ... (a) Stratigraphy and paleosol distribution of the IITK drill core. A total of 4 major stratigraphic units and 13 paleosols were identified in this core covering a time span of ~100ka. The entire core is dominated by muddy sediments with thin silt layers at regular intervals. (b) Stratigraphy and paleosol distribution of the Bhognipur drill core. A total of 6 major stratigraphic units and 10 paleosols were identified in this core. This entire core is distinctly coarser in the lower parts with >10m sand body representing a major channel. ... Depth distribution of pH, EC, CaCO3, OC, particle size distribution and textural class of the IITK core. ... Study area in the Ganga–Yamuna interfluve (GYI) showing drill core at Indian Institute of Technology, Kanpur (IIT, K) and Bhognipur, Kalpi (BHOG, K).
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  • (a) Principal tectonic features of the New Ireland and Manus Basins, showing the location of the TLTF volcanic chain, the active New Britain volcanic arc (subdivided into the main arc, Rabaul–Tavui, and the backarc Witu Islands) and Bagana (modified after Herzig et al., 1998). Place name abbreviations: NI, New Ireland; NH, New Hanover; PNG, Papua New Guinea; BI, Bougainville Island. (b) Enlargement of the area within the dashed rectangle, showing the EDISON I and II core stations superimposed on the bathymetry from 1000–4000 mbsl contoured at 500 m intervals (the 1000 mbsl contour east of New Ireland is omitted for clarity). For the Feni group, Ambitle (A) and Babase (B) Islands are labelled. ... Ash beds in the New Ireland sediment cores plotted against calendar age (note change of scale at 30 ka). All documented eruptions from the TLTF volcanoes are older than 500 ka with the exception of one from Feni (Wallace et al., 1983; Licence et al., 1987). Rabaul eruptive history after Nairn et al. (1995). ... Location of sediment core stations ... Sediment ages obtained by AMS 14C ... δ18O profiles plotted against calendar age for the sediment cores. All values of δ18O were determined relative to PeeDee Belemnite. The stacked low-latitude oxygen isotope record of Bassinot et al. (1994) is provided for reference, together with δ18O stages (italics) separated by dashed lines. EoC=sediment age at the base of each core. Ages could not be assigned to sediments older than 18 ka in core 17677 (see text).
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  • Location of the marine sediment cores investigated in this study, and mean austral summer (A) and winter (B) sea surface temperatures (SST) (color shading, °C; Locarnini et al., 2010) plotted together with mean annual horizontal circulation at the surface (black arrows; Stramma and England, 1999). During austral summer (winter) the Brazil Current is strengthened (weakened) and our study area experiences higher (lower) SST (Matano et al., 1993; Locarnini et al., 2010). ACC: Antarctic Circumpolar Current; BC: Brazil Current; NBC: North Brazil Current; SAC: South Atlantic Current; SSEC: Southern South Equatorial Current. This figure was partly produced with Ocean Data View (Schlitzer, 2012). See Table 1 for more information about the sediment cores. ... Proxy records for the upper Brazil Current spanning the late Holocene based on marine sediment cores GeoB2107-5 and GeoB6211-1/2. (A) GeoB2107-5 Globigerinoides ruber white (w) δ18O; (B) GeoB2107-5 Globorotalia truncatulinoides dextral (d) δ18O; (C) GeoB6211-1/2G. ruber w δ18O; (D) GeoB6211-1/2 permanent thermocline (i.e., GeoB6211-1 G. truncatulinoides d and GeoB6211-2 Globorotalia inflata) δ18O; (E) GeoB6211-1/2 G. ruber w Mg/Ca sea surface temperatures (SST); and (F) GeoB6211-1/2 ice volume corrected (ivc) surface seawater (ssw) δ18O, a proxy for local sea surface salinity. Note that (A) and (C), and (B) and (D) are plotted on the same y-axis scale to facilitate comparison. In (A)–(D) the black lines represent a three-point running average. ... Centennial-scale variability of the Brazil Current during the late Holocene compared to circum-Atlantic climate records. (A) Low sea surface temperatures (SST) events from marine sediment core LO09-14 collected in the subpolar North Atlantic at 58.94°N/20.41°W (Berner et al., 2008); (B) Detrended Mg percentage in calcite from lacustrine composite sediment core E96-1P/E96-5M/E96-6M collected in eastern equatorial Africa at 0.29°S/29.71°E (Russell et al., 2003; Russell and Johnson, 2005); (C) Δδ18O Globigerinoides sacculifer – Globorotalia tumida from marine sediment core GeoB3910-2 collected in the western South Atlantic at 4.25°S/36.35°W (Arz et al., 2001); (D) δ18O from composite stalagmite LG3/LG11 collected in central-eastern Brazil at 14.42°S/44.37°W (Strikis et al., 2011); (E) Globigerinoides ruber white (w) δ18O from marine sediment core GeoB2107-5 collected in the western South Atlantic at 27.18°S/46.46°W (black line represents a three-point running average) (this study); (F) ice volume corrected (ivc) surface seawater (ssw) δ18O from composite marine sediment core GeoB6211-1/2 collected in the western South Atlantic at 32.51°S/50.24°W (black line) (this study) together with a sinusoid with period of 730yr (gray line). See Table 3 and the Discussion for more information about records (A)–(D). ... Late Quaternary... Age model and sedimentation rates for marine sediment cores GeoB2107-5 and GeoB6211-1/2. Solid black line refers to core GeoB6211-1, and solid gray line refers to core GeoB6211-2. Cores GeoB6211-1 and GeoB6211-2 were used to produce the composite record GeoB6211-1/2. ... Marine sediment cores used in this study.
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  • Radiometric dates from Lake Titicaca cores and altiplanean outcrops. The radiocarbon dates were calibrated using the Calib 3.0 program (Stuiver and Reimer, 1993) ... Summary pollen percentage diagram for core TD1, Lake Titicaca (from Mourguiart et al., 1995c). ... Temperature and water depth variations reconstructed from (a) pollen and (b) ostracod studies (core TDI, Lake Titicaca; after Argollo and Mourguiart, 1995b, c). ... Lake Titicaca and Lake Pocoyu level fluctuations during the last 32,000yr compiled from references discussed in the text. Triangles represent dated samples from lacustrine terraces; vertical lines represent results from the pollen analysis; the full line represents results from the transfer function on ostracods (cores TD1 and TJ from lakes Taraco-Guaqui and Chucuito, respectively; standard error of 0.81 and 2m approximately); the intermittent line represents historical data. High lake levels are highlighted with shaded bands.
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