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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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  • Variation of CO3, SO4, Corg, CIA, SiO2/Al2O3, Zr/Al2O3 and TiO2/Al2O3 in the geochemical zones along the depth profile. Magnetic susceptibility of bulk sediments and mean grain size from Ortega-Guerrero et al. (1999) are also shown (for stratigraphic description see Fig. 2). ... Stratigraphic description of the 950cm long sediment core collected from the central part of paleo-lake San Felipe (a) and sedimentation rates along the depth profile calculated from AMS 14C dates (b). ... Late Quaternary... AMS radio carbon dates from the bulk sediments of San Felipe core. ... Lacustrine sediments
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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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  • Huntec seismic survey tracklines and core locations. ... Huntec boomer section showing the location of piston core TUL96B-02 (see Fig. 13), which is located in a region transitional between acoustically stratified glacial marine sediments of unit 3a and unstratified glacial marine sediments of unit 3b (not in section shown). Glacial marine sediments are overlain by unstratified post-glacial sediements of unit 4b. Water depth at the deepest point is 138m. ... Huntec boomer section showing truncation of stratified reflectors in glacial marine sediments (unit 3a) by postglacial sediments (unit 4a). Erosion of the glacial marine sediments (unit 3a) in the location of core TUL97-12 (Fig. 10) has allowed sampling of the lowermost facies of the glacial marine section. Water depth at the deepest point is 59m. ... Lithologic description, physical properties, and grain size measured in two cores considered representative of the upper facies of glacial marine unit 3a. Post-glacial sediments of unit 4a were sampled at the top of both cores. ... sediment physical properties... Quaternary stratigraphy... Lithologic description and physical properties measured in two cores showing an example of the differences in lithology and physical properties between the acoustically stratified post-glacial sediments of unit 4a (TUL96B-04) and acoustically unstratified and coarser grained psot-glacial sediments of unit 4b (TUL97B-12). The positions of radiocarbon ages are given along the right side.
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  • Map showing location of studied cores and drainage network of the Sea of Marmara. ... Geochronology of Sea of Marmara sediments obtained by linear extrapolation using the 14C dates in Table 1 and assuming uniform sedimentation rates between the dated intervals. Ages are in kyr BP (N.A.: not applicable) ... Lithological logs of cores in central part of Bosphorus Strait. Numbers on top refer to the water depth and those along the core length are radiocarbon datings. ... 14C dates, δ13C values and sedimentation rates at Site BPMB-14 in Bosphorus. AMS date is shown in bold italic ... 14C dates, δ13C values and sedimentation rates in the Sea of Marmara sediment cores. AMS 14C dates are shown in bold italic
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  • Radiocarbon age–depth model for the Narrows Lake sediment core from Pourquoi-Pas Island, with sediment accumulation rates for Narrows Lake and Col 1 Lake. ... Diatom stratigraphy of the Narrows Lake sediment core including statistically significant diatom zones. Marine diatom taxa are grouped to the right of the diagram, and freshwater to the left. Only species with a relative abundance exceeding 2% are shown. ... Radiocarbon age depth models and sediment accumulation rates for the Col Lake 1 sediment core from Horseshoe Island. One outlier is excluded from age–depth Model 1. The radiocarbon dates at 94–95 cm and 110–111 cm are both in a poorly defined area of the radiocarbon calibration curve and their two age ranges overlap – this means that although their mean ages create an age reversal, they could still be in sequence. Model 2 shows this alternative scenario, which we consider to be less likely. ... Stratigraphic analyses of the 1.3 m lake sediment core from the Narrows Lake, Pourquoi-Pas Island including sedimentary logs, physical properties and the presence of moss macrofossils and eggs of the fairy shrimp Branchinecta gaini. ... Stratigraphic analyses of the 1.11 m lake sediment core from Col Lake 1, Horseshoe Island including sedimentary logs, physical properties and the presence of moss macrofossils and eggs of the fairy shrimp Branchinecta gaini.
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  • Location map of the Sambhar playa in the Thar Desert; the playa is fed by the Mendha River from NE and the Rupangarh from SW. The western parts of the playa are covered with Quaternary aeolian deposits and the easternmost parts are used for salt production. A ∼23 m deep borehole, BH, was drilled in the center of the playa to obtain continuous core samples. ... Radiocarbon ages of the Sambhar playa core sediments, Thar Desert ... Variation of concentration of major cations and anions in (water) leachable fraction of core sediments with depth; (a) Mg2+, K+, (b) Na+, Ca2+, (c) Cl−, SO42−. Note the co-variance of Na+ and Cl− (reflects amounts of halite) and Ca2+ and SO42− (reflects gypsum content). A clear dominance of sulfates in the lower parts and that of chloride in the upper parts of the core is noticeable. The peaks of Mg2+ and K+ coincide with the occurrences of kieserite (MgSO4·H2O) and polyhalite (K2Ca2Mg(SO4)4·2H2O) respectively in the sediment samples. ... Carbonate mineralogy and geochemistry of core sediments from the Sambhar playa ... Quaternary climate... Evaporite facies identified in the Sambhar playa core, Thar Desert
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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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  • Raw and calibrated radiocarbon results for all fractions and the corresponding sediment depths for core site C90m ... Raw and calibrated radiocarbon results for all fractions and the corresponding sediment depths for core site C230m ... Location, water depth, and core length for the core sites used in this study ... Down-core bulk decalcified, humate, and humin age results for the three core sites: (a) C90m, (b) C150m, (c) C230m, plotted with respect to calendar age, sediment depth below surface, and a simplified stratigraphy. Solid lines indicate the model used to assign ages to down-core results. Age models are based upon ages from bulk decalcified and humin (humin) sub-fractions in the post-13,500 yr BP (pre-13,500 yr BP) interval. ... Lake sediments... Raw and calibrated radiocarbon results for all fractions and the corresponding sediment depths for core site C150m
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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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