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Sedimentological and stratigraphical profiles of all cores and pits along transects A, B and C (see Fig. 2 for location). ... Ostracods and macrofossil counts in selected sediment samples from the study area. ... Field photographs of key sedimentary and surface features, and macrofossils. a) Yardang. b) Cliffed gravel platform. c) Vesicular surface on lake floor (F1). d) Elevated pebbles from salt heave processes. e) Reddish sand with carbonate concretions overlain by gravel lag. f) Gravel with well-developed carbonate coatings. g) Wind abraded surface. h) Lag deposit of pebbles, sand and carbonate tubules. i) Sandy (above) to pebbly (below) surface sediment along the spit (GS). j) Juvenile Diacypris spinosa. k) Predator hole in Reticypris sp. carpace. l) Charophyte oogonia. ... Google Earth caption of main geomorphological features in the Lake Frome shoreline study area. Black crosses mark DGPS readings, numbered red dots mark locations of sediment cores and pits in Fig. 6. Note reddish surface appearance on spit shoulder around point 25, and dark grey gravel patches on the lake floor (e.g. adjacent to point 33). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.) ... Geographical setting of Lake Frome study area. a) Location in Australia. b) Main topographical features in the Lake Frome and Callabonna area; lake area as defined by modern shoreline in light blue, area of maximum late Quaternary lake highstand as defined by 15 m contour line in dark blue. Lake bathymetry is illustrated with white contour lines below 0 m AHD spaced at 0.5 m intervals (adapted from Draper and Jensen, 1976). White circles mark locations of dated beach ridges (Cohen et al., 2011 & 2012; Gliganic et al., 2014), grey circles mark locations of dated lacustrine records (e.g. Bowler et al., 1986; Singh, 1981; De Deckker et al., 2011). Dune ridges around the lake margins are illustrated by grey lines, main creeks are dotted lines. c) Landsat TM image (band combination 3-2-1) at the end of the dry season 2011 illustrating the high reflectivity (white colour) of salts at the surface of Lake Frome. d) Landsat image (band combination 3-2-1) at the end of the wet season during the largest historically reported filling event in 1974 with approximately 90% of the lake floor covered by water. Note plumes of fine-grained sediment entered the lake from the Flinders Ranges. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.) ... Late Quaternary
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Schematic representation of water columns in the modern tropical western and eastern Atlantic Ocean with approximately depth of water masses (after various authors, see text). Mixed Layer = mixed surface water layer; SACW = South Atlantic Central Water; AAIW = Antarctic Intermediate Water; NADW = North Atlantic Deep Water; AABW = Antarctic Bottom Water. Water depth of core positions is indicated. ... RDA diagram (combined data sets of cores GeoB 2204-2 and GeoB 1105-4) of species accumulation rates in relation to the variable TOC (dashed arrow). Scale of axes is given in standard deviations. For abbreviations of species names, see Fig. 6. ... late Quaternary... Accumulation rates of the total sediment calculated according to the following equation (a). Average values of total sediment accumulation rates are given for both cores (b). Data for SR and DBD after Rühlemann (1996; Core GeoB 2204-2) and Meinecke (1992; GeoB 1105-4) ... Positions of sediment traps (S, E, PB, P1) after Dale (1992a, b) and core positions (GeoB 1105-4, GeoB 2204-2). Sediment trap data (Dale 1992a, b): Mean values of individuals cm−2 ka−1 are given for one station including sediment trap data of different water depths. Others include: Sphaerodinella albatrosiana, Calciodinellum operosum, cysts of Scrippsiella (= Rhabdothorax spp.), Bicarinate-type, ?calcareous cyst sp., unidentified calcareous cysts. For abbreviations of species names, see Fig. 6. ... Lithology and position of samples (used for calcareous dinoflagellate studies) of cores GeoB 1105-4 (Wefer et al., 1989) and GeoB 2204-2 (Bleil et al., 1994).
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Percentages of the 15 more important species and groups of species and Shannon–Wiener H(S) diversity index of the studied samples in the sediment cores. ... Distribution of the identified Biofacies along the studied cores and correlation. ... Boundaries of the biofacies in the six cores ... Fig. 3 represents the correspondence analysis results for the 15 more significant benthic foraminiferal species and group of species of our study. The sum of all eigenvalues obtained from Correspondence Analysis (CA) is 0.83 (Table 3). The A1 axis has eigenvalue λ1 equal to 0.34 of the total dispersion of the species scores on the ordination axis, and the A2 axis has eigenvalue λ2 equal to 0.25. However, cumulative percentage variance of species–sample relations for the two axes reaches 52.87. Therefore it displays statistically relevant information and can be further used for an environmental interpretation. Species showing similar distribution patterns and related to the same environmental conditions are plotted close to each other on the CA graph. The CA plot of species scores shows the high concentration of species in the centre of the ordination diagram. Thus, these species may have their statistical optima there or alternatively may have a very weak correlation with integrated environmental parameters. Species Correspondence Analysis distinguishes the benthic foraminiferal assemblages in four clusters. The frequencies of the taxa belonging to these groups have been summed and plotted for each core (Fig. 4a–f).Table 3Eigenvalues.Value%SimilarityCumulativeEigenval 10.3430.2730.27Eigenval 20.2522.652.87Eigenval 30.1412.3365.2Eigenval 40.19.3874.58Sum0.83... The analysis of fossil sediments is based on 6 gravity cores (EYB: 1, 10, 6, 5, 7, 8) ranging in length from 113 to 255 cm and retrieved by a trawler vessel from the south shelf, slope and basinal setting of the North Evoikos Basin. Details of the cores are reported in Table 1 and depicted in Fig. 2.Table 1Details of the sediment cores: location, depth and lengthCoresLatitudeLongitudeWater depth (m)Length (cm)EYB-1023,39937938,61649581120EYB-123,3691638,63362785113EYB-623,3077738,723095186140EYB-523,28016838,71548258145EYB-723,23828938,74451375255EYB-823,17547238,770684416195... General bathymetry and coring locations in the North Evoikos Gulf. ... Details of the sediment cores: location, depth and length
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Comparison of the clay mineralogical signatures of the recent (i.e., mean for oxygen isotope stage or OIS 1) sediments of CONTINENT and Verhashagin cores with the uppermost part of short cores recovered all over the lake. The data are reported from North to South. ... Clay mineralogical assemblages of piston core CON01-605-3 on Vydrino Shoulder, piston core CON01-604-2 and pilot core CON01-604-2a on Posolsky Bank and, piston core CON01-603-2 and pilot core CON01-603-2a on Continent Ridge. The clay assemblages of two cores from the Academician ridge are shown for comparison (data from Fagel et al., 2003). The mean assemblage composition of the surface sediments of Selenga River is shown for comparison. ... List of minerals found in Baikal sediments and/or the Selenga River watershed ... Result of cluster analysis based on detrital heavy mineral compositions of samples from the studied piston cores and various Quaternary sediments in the Baikal region. The abbreviations refer to the core locations (CR=Continent Ridge, VS=Vydrino Shoulder, PB=Posolsky Bank, ZP=Zalina Proval). The numbers indicate the sampling depths in cm. ... Bulk and clay mineralogy of Recent sediments from the upper parts of gravity (GC) and piston cores collected in the various Lake Baikal sub-basins and main river tributary deltas
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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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(a) The physiography of the East Sea (courtesy by Prof. K.I. Chang, Seoul National University) and the location of four core sediments. (b) The surface- and deep-circulation patterns in the East Sea (courtesy by Dr. J.J. Park, Seoul National University). (c) The satellite view of sea surface temperature in the East Sea (courtesy by NFRDA). ... The chronostratigraphic construction of core GH99-1239 with a stratigraphic comparison to a well-dated core GH99-1232 (modified from Itaki and Ikehara, 2003). ... Downcore variation of the sedimentary organic matter δ13C and δ15N values of the four sediment cores in the East Sea. (a) GH99-1239, (b) GH99-1246, (c) KT92-13P5, and (d) 96EBP4. KT92-13P3 and 96EBP4 were partly published by Minoura et al. (1997) and Khim et al. (2007), respectively. ... The average δ13C and δ15N values of sedimentary organic matter of the core sediments ... Correlation between the δ13C and δ15N values of sedimentary organic matter measured in the four sediment cores (a) GH99-1239, (b) GH99-1246, (c) KT92-13P5, and (d) 96EBP4.
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Clay mineralogical data: ratios of relative contents of illite to chlorite (+ kaolinite) and smectite to illite. Smectite crystallinity is computed as IB and illite crystallinity computed as HHW (smaller values correspond to higher crystallinity). Original data are indicated by small circles and plotted as thin lines; thick lines are smoothed (as in Fig. 4). Core intervals related to precession minima are marked in light grey and those relating to precessional maxima in dark grey. ... Quaternary... clastic sediments... (A) Map of the study area with location of core GeoB 3375-1 and principal oceanographic features (after Strub et al., 1998). Distribution of Quaternary volcanism and forearc alluvial basins (after Thornburg and Kulm, 1987b), continental hydrology and climatic zonation (after Heusser, 1984). (B) Geological map of Chile between 25°S and 30°S (after Zeil, 1986and Thornburg and Kulm, 1987b). Dashed lines in the northern part indicate recent dry valleys. ... Silt grain-size data. Sorting and median show cyclic variations. High resolution silt grain-size distributions are plotted for the extremes of each cycle for the carbonate-free fraction (left) and carbonate fraction (right). Additionally, the carbonate content record is shown on the right side. Thin lines with data points represent the original data set, thick lines are smoothed curves (except for silt grain-size distributions). The lines were smoothed by using a three point moving average. Core intervals related to precession minima are marked in light grey and those relating to precessional maxima in dark grey. ... Age model for sediment core GeoB 3375-1. Age control points (indicated by arrows, see Table 1) include three 14C AMS dates and a graphical correlation point of the δ18O record of N. pachyderma (sin.) with the SPECMAP δ18O stack (Imbrie et al., 1984). Further downcore two more control points were obtained by correlation of the median of the silt fraction (thick line represents smoothed record performed by three point moving averaging) with the precession index (after Berger and Loutre, 1991). Resulting sedimentation rates are plotted to the right. ... Age control points of core GeoB 3375-1
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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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Latitude, glacial rain rates and glacial 231Paex/230Thex ratios of several sediment cores (Kumar et al., 1995) ... PS2499-5: age, mean sedimentation rate, 230Th constant flux sedimentation rate, bulk SAR and rain rate ... PS248-1: core depth and corresponding age, initial 230Thex, mean sedimentation rate, 230Th constant flux sedimentation rate, bulk SAR and rain rate ... Average 231Paex/230Thex ratios for the isotope stages 1 to 5 of sediment core PS2499-5 (circles), glacial (boxes) and interglacial (crosses) 231Paex/230Thex ratios of several sediment cores (Kumar et al., 1995), plotted against bulk sediment rain rate. ... Sediment accumulation rates (SAR) [g/cm2 kyr] of the cores PS2498-1 and PS2499-5 compared with the sediment redistribution corrected rain rate vs. age. The error bars mark the standard deviation of the mean (1 σ) of the 230Thex activities. The shaded areas mark the glacial stages 2 and 4.
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Sediment chemical analysis of the core Xinias 1. ... Preliminary reconstruction of past lake-level changes in Lake Xinias, based on the lithology of the single sediment core sampled by Bottema (1979). ... Late Quaternary lake-level changes... Department of Quaternary Geology, Lund university, Tornavägen 13, S-22363 Lund, Sweden... Ostracods in selected samples of the early Holocene aragonitic (samples 1 and 2) and calcitic (samples 3 and 4) sediment in core Xinias 1a ... sediment stratigraphy... Topographic map of the past Lake Xinias, showing the location of the studied transect of sediment cores. The shoreline before the recent drainage is indicated by broken line. ... Correlation of the cores Xinias 1–5 in the stratigraphical transect and the separate core Xinias 6.
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