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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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  • late Pleistocene... Interpretive core logs of the sediments recovered from Cap Timiris Canyon indicating hemipelagic deposits and turbiditic sequences. Sediments from the canyon (GeoB 8509–2) are heavily intercalated with thin turbidite deposits of 2 to 40 cm thickness, whereas the levee sediments (GeoB 8502–2 and GeoB 8507–3) are less influenced by turbidity currents. Question marks indicate reworked turbidite deposits. Age control for GeoB 8509–2 is shown by radiocarbon dates. Sediments of GeoB 8507–3 and the investigated upper sequence of GeoB 8502–2 from the proximal and distal levee are correlated to isotope-dated reference cores (Wien et al., 2006) and date back to 55 and ∼70 ka, respectively. ... marine sediments... Relative proportions of modelled end-member grain-size distributions for a) the distal levee site GeoB 8502–2, b) the proximal levee record GeoB 8507–3 and c) the intra-canyon core GeoB 8509–2 of Cap Timiris Canyon since late Pleistocene times. Note that the age model of sediment core GeoB 8509–2 is based on radiocarbon dates. According to the core-to-core correlation it would date back to ∼15 ka (Wien et al., 2006, see also 3.1 this study). ... Sediment texture with weight-percentages for a) sand, b) silt and c) clay fractions, d) terrigenous silt fraction and e) bulk carbonate content of the three gravity cores recovered from Cap Timiris Canyon (see text for details). ... Grain-size distributions for sediment core GeoB 8502–2 at the distal levee of Cap Timiris Canyon. Displayed are grain sizes for the bulk silt fraction (BS), the terrigenous (TS) and the carbonate silt fraction (CS), respectively, during the past 70 ka. ... Photos of the X-ray radiographs of sediment core GeoB 8509–2 showing bioturbated hemipelagic sediments in the lower and upper most part of both pictures as well as turbidite deposits in the middle. Picture a) of 869–890.5 cm core depth shows a fining upward turbiditic sequence with cross lamination at the base followed by fine laminated silt and fine-grained hemipelagic mud. Picture b) of 444–462 cm core depth (see Fig. 2) displays very fine-grained laminated mud deposits.
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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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  • Modal abundance and vertical distribution of heavy minerals in core ZX1 divided into units A (20.0–14.9m), B (14.9–10.5m), C (10.5–2.7m) and D (2.7–0.5m). Percentages have been normalised to account for the presence of rock fragments in the heavy mineral assemblages. (1) Metamorphic minerals are garnet, staurolite, sillimanite, kyanite and chloritoid; (2) ZTRA represents zircon, tourmaline, rutile and apatite. ... Late Quaternary sediment log of core ZX1 showing general lithology, grain size, sediment description, heavy mineral and foraminifer assemblages in relation to sea-level change, depositional environment and climate fluctuation. ... Map showing morphological features of the Yangtze delta plain and location of core site (after Chen, 1999). ... Depths and ages of radiocarbon-dated samples from core ZX1 ... Modal abundance of detrital grains in core ZX1
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  • Vertical profiles of sediment cores from the Algiers area: KMDJ01 (a), KMDJ02 (b), KMDJ03 (c), KMDJ04 (d). Basic sedimentological parameters, magnetic susceptibility, are shown with relative abundance of bio- and geo-indicators of sediment's provenance. Ages are calendar 14C ages. ... Vertical profiles of sediment cores from the Chenoua–Tenes area: KMDJ06 (a), KMDJ07 (b), KMDJ08 (c). Basic sedimentological parameters, magnetic susceptibility, are shown with relative abundance of bio- and geo-indicators of sediment's provenance. Ages are calendar 14C ages. ... (A). Detailed maps of the Algiers area locating position of analysed sediment cores. (B). Detailed maps of the Chenoua–Tenes area locating position of analysed sediment cores. ... Sediment cores... Late Quaternary... Chronology of the seven cores ... Comparison of accumulation sediment rates of seven studied sediment cores. Thickness of debris flow interval of KMDJ01 was not taken into account.
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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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  • CHIRP-sonar profiles KS143 and KS37 show an example of localized turbid zones (TZ) within the late Quaternary transgressive deposit above reflector ES1 (profiles location in Figs. 7,11). These acoustic anomalies occur where shallow faulting affect the pre-TST units (arrows in lower profile) and possibly connect deposits of slightly higher permeability. These offsets facilitate fluid expulsion from deeper impregnated levels. ... Simplified stratigraphic scheme of the late Quaternary deposits on the western margin of the central Adriatic Sea. The SPECMAP curve (Martinson et al., 1987) is reported to show the inferred age of units within the last sequence (s1) and the overlying late Pleistocene to early Holocene TST and the late Holocene HST. ... late Quaternary... CHIRP-sonar profiles CSS538 and YD7 show reflector discontinuities affecting downlapping reflectors within the distal forced regressive unit of sequences S1 (A) and of sequences S2 and S3 (B). The otherwise uniform reflectors appear interrupted by transparent intervals and show small diffraction hyperbolae emanating from their clear-cut edges (upper inset). These acoustically transparent areas do not extend to the underlying downlapping units or to the overlying late Quaternary transgressive and highstand drape. ... sediment deformation... (A) CHIRP-sonar profile CSS700 and line drawing illustrate the overall stratigraphy of the western Adriatic margin. ES1–3 denote regional erosion surfaces that record subaerial exposure and successive wave reworking at the top of forced regressive wedges (these surfaces are numbered 1 to 4 in Trincardi and Correggiari, 2000 and Ridente and Trincardi, 2002). A thick transgressive systems tract (TST) includes a progradational unit encased in marine mud. The late Holocene highstand systems tract (HST) mud wedge in this section shows seafloor and subsurface irregularities that do not involve the TST section beneath the subhorizontal maximum flooding surface (mfs). Reflector irregularities possibly suggest sediment deformation also in older deposits (black arrow) ascribed to the former highstand of sea level within depositional sequence S1. (B) Profile KS11 (ca. 50 km to the north) shows a simple sigmoidal geometry of the late Holocene HST in the lack of sediment deformation. ... Bathymetric map of the central Adriatic reporting the extent of all evidence of acoustically transparent and/or irregularly stratified reflector packages here ascribed to soft sediment deformation older than the late Holocene HST. Bathymetric contour interval is 5 m except in water depths greater than 200 m, south east of the Gargano Promontory. Structural elements are reported from Fig. 1.
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  • Hydrogen index values determined at long sediment cores PS2741-1, PS2763-7, and PS2761-10. The Holocene time interval is marked by the shading. Dark gray, organic carbon enriched lithologies are marked as dark gray bars. ... Magnetic susceptibility records of six sediment cores from the Kara and Laptev Sea continental margin used for core correlation. Arrows and numbers mark reservoir-corrected AMS 14C ages. Water depths are given in the lower right corner of each record. ... AMS 14C datings performed on marine bivalves from cores PS2718-6 and PS2719-1 at the “Leibniz-Labor für Altersbestimmungen” of Kiel University (see text for further explanation), and linear sedimentation rates ... Average linear sedimentation rate, bulk accumulation rates and accumulation rates of total organic carbon determined at cores PS2138-1, PS2741-1, PS2474-3, PS2767-4, PS2763-7, PS2757-8, and PS2761-10 (cf. Table 2) ... Magnetic susceptibility of long sediment cores (see Fig. 1 for location) representing oxygen isotope stages 1–6 and used for core correlation and stratigraphic framework. Arrows and numbers mark reservoir-corrected AMS 14C ages (data from Core PS2767-4; Spielhagen, 1997, unpublished data). The Holocene time interval is marked by light gray shading. Dark gray, organic carbon enriched lithologies are marked as dark gray bars. ... Late Quaternary
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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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  • 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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