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  • Location of studied surface sediment samples (Ormara transect, Hab-transect off Karachi and Indus transect) ... Location of studied surface sediment samples (Ormara transect, Hab-transect off Karachi and Indus transect) and core SO90 137KA off Pakistan. ... Proxies from coarse fraction analysis of core 137KA indicating aragonite dissolution: (A) coarse fraction content (>63 μm); (B) relative abundance of pteropods and heteropods including fragments; (C) Limacina inflata dissolution index distinguishing six dissolution stages, from 0 (perfect preservation) to 5 (worst preservation); (D) pteropod fragmentation index: fragments/(fragments+whole tests); (E) GISP2 Greenland ice core record (Grootes et al., 1993); bioturbation scale: dark grey=distinctly to indistinctly laminated sediments, light grey=indistinctly laminated sediments, white=bioturbated sediments, modified after von Rad et al., 1999). ... Geochemical proxies of core 137KA indicating organic and carbonate productivity (modified after von Rad et al., 1999): (A) total organic carbon (TOC) content; (B) bulk calcium carbonate content; (C) strontium concentration; (D) bulk aragonite content; (E) GISP2 Greenland ice core record (Grootes et al., 1993); bioturbation scale: dark grey=distinctly to indistinctly laminated sediments, light grey=indistinctly laminated sediments, white=bioturbated sediments, modified after von Rad et al., 1999). ... Sketch showing the two pteropod preservation modes in sediment core 137KA off Pakistan: (a) present-day situation with shallow deep winter mixing due to a weak NE monsoon, stable OMZ, absence of pteropods in core 137KA, pteropod occurrence restricted to shelf/upper continental slope; (b) good to excellent preservation during times of intermediate water formation down to 600 m water depth. The position of core 137KA is indicated by a star. ... Late Quaternary
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  • Location, depth, total core recovery, length of core section studied (cm below seafloor) and dominant lithology of sediment cores collected adjacent to the CLSC ... Ages determined for cores adjacent to the CLSC with 14C techniques and the depth within the cores where the 120-ka disappearance level of Globigerinoides ruber (pink) is located ... Principal component loadings for three components in the HCl soluble fraction, recalculated on a detrital-free, CaCO3-free basis of sediments from cores collected adjacent to the CLSC, after subtraction of volcaniclastic layers ... Downcore plots of the HCl soluble Mn concentrations (wt%) recalculated on a detrital-free CaCO3-free basis of sediment cores collected adjacent to the CLSC, indicating the ages (ka) of Mn peaks in each core as calculated from interpolation of 14C and palaeobiostratigraphic dates. Depths are recalculated (cmbsf*) after subtraction of volcaniclastic layers. *Peaks in Mn in core SO67/159 were determined using δ18O stratigraphy data after Gehrke (1992). ... Summary of bulk element concentrations and mean element partitioning of calcareous sediments in cores collected adjacent to the CLSC (n=40) ... hydrothermal sediments
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  • X-radiographs of core MW-1. (a: Planar cross lamination, b: plant fragments). ... Multi-proxy data of core MW-1. ... Stratigraphic description of core MW-1. ... Late Quaternary stratigraphy... Palynomorph percentage diagram for core MW-1. ... Topographic map of the study area with the coring site (core MW-1). (1: Kyunggi Bay, 2: Cheonsoo Bay, 3: Hampyung Bay, 4: Haenam Bay).
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  • Paleoenvironmental Reconstructions from Marine Sediments @ AWI
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  • 230Thexcess profile in cores BC 14, BC 20 and BC 25 showing sedimentation rates of 0.27, 0.23 and 0.23cmka−1, respectively. ... Compositional (EDS) analysis (wt%) of glass shards for each layer obtained for each sub-samples from the three sediment cores. The data of core BC 8 are provided for comparison. ... Comprehensive facts of the several parameters studied of the volcanic horizons from the CIB sediment cores. ... Correlation of abundance of glass shards (no of shards g−1 of sediment) in BC 14, 20 and 25 with respect to age (ka) of the cores, with Cr/Sc ratio of bulk sediments and ash wt% based on Cr (Image 1) and Nb (Image 2) concentration normative calculations. Note the presence of volcanic activity indicated by abundance of glass shards, Cr/Sc ratio and single element normative calculations and excellent correlation in all the ash layers in all the three cores. Elemental concentration in ppm. ... Details of sub-samples recovered from three sediment cores from the CIB.
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  • Late Quaternary climate dynamics... The Tortoise Lagoon (TOR) summary pollen and charcoal record against depth (cm) and age (cal yr BP). Also shown is the lithology of the sediment core with black representing peat sediments, brown reflecting lake muds and yellow representing sandy peats that occur towards the base of this record. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.) ... The Native Companion Lagoon (NCL) summary pollen and charcoal record against depth (cm) and age (cal yr BP). Also shown is the lithology of the sediment core with black representing peat sediments and yellow reflecting sandy peats that occur towards the base of this record. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.) ... The Principal Component Analysis (PCA) and key pollen taxa plotted on a common age scale from the three sites. Also shown are the OZ-INTIMATE climate events (Reeves et al., 2013a, see text for details). LGIT = Last Glacial Interglacial Transition; LGM = Last Glacial Maximum. The early and late deglacial of Reeves et al. (2013a) have been combined into the LGIT. ... Lake sediments... The Welsby Lagoon (WEL) summary pollen and charcoal record against depth (cm) and age (cal yr BP). Also shown is the lithology of the sediment core with black representing peat sediments and yellow reflecting sandy peats that occur towards the base of this record. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.) ... Radiocarbon Dates for the three North Stradbroke Island sites. Data shown includes sample depth, laboratory, 14C age and calibrated age (INTCAL 09; Reimer et al., 2009) for each of the cores. NC is the code for the samples taken from Native Companion Lagoon (17 14C samples); TOR is the code for the samples taken from Tortoise Lagoon (6 + pollen concentrate 14C samples); and Welsby or WEL is the code for samples taken from Welsby Lagoon (17 14C samples). Radiocarbon not used in the age models for each record have a NA in the calibrated age column.
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  • Overview of dosimetric data and IRSL-ages obtained from cores Lz1027 and Lz1028. Please note that the water content is given in relation to dry sediment weight. ... Lithology, grain-size and selected biogeochemical data of core Lz1028. Obtained ages and interpretations are given on the right side. Please note that the water content is given in relation to wet sediment weight. ... Location of Lake El'gygytgyn in northeastern Siberia (upper part) and position of sediment cores at the southern shelf and in the deepest part of the lake (lower part). Digital elevation model after Kopsch (2005); lake bathymetry after Belyi (2001). ... Model of lake-level changes of Lake El'gygytgyn as derived from cores Lz1027 and Lz1028 from the southern lake shelf. The oldest sediments of Unit IV from core Lz1028 indicate a deep-water period prior to 185ka although the exact range of the level cannot be deduced from the sediments (a). Between 185ka and prior to 40ka at least one period with low lake level and subsequent erosion has to assumed (b). The exact lake level is not known for this period as well. During MIS 3 or an older warm stage, the lake level was probably 10m higher than in present (c) while it decreased during MIS 2. In late glacial times the lake level was around 10m lower than today (d). The bench was formed due to the onset of wave action at this level. Furthermore, beach sediments (Unit II) were deposited at the position of Lz1027. Subsequently, the lake level rose quickly to the Holocene level and the present shelf conditions with limited sedimentation came into being (e). Please note that the profiles are directed from the shelf to the crater rim. ... Late Quaternary... Lithology, grain-size and selected biogeochemical data of core Lz1027. Obtained ages and interpretations are given on the right side. Please note that the water content is given in relation to wet sediment weight.
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  • Abstract: A model is presented for hemipelagic siliciclastic and carbonate sedimentation during the last glacial-interglacial cycle in the Capricorn Channel, southern Great Barrier Reef (GBR). Stable isotope ratios, grainsize, carbonate content and mineralogy were analysed for seven cores in a depth transect from 166 to 2892 m below sea level (mbsl). Results show variations in the flux of terrigenous, neritic and pelagic sediments to the continental slope over the last sea level cycle. During the glacial lowstand terrigenous sediment influenced all the cores down to 2000 mbsl. The percentages of quartz and feldspar in the cores decreased with water depth, while the percentage of clay increased. X-ray diffraction analysis of the glacial lowstand clay mineralogy suggests that the siliciclastic sediment was primarily sourced from the Fitzroy River, which debouched directly into the northwest sector of the Capricorn Channel at this time. The cores also show a decrease in pelagic calcite and an increase in aragonite and high magnesium calcite (HMC) during the glacial. The influx of HMC and aragonite is most likely from reworking of coral reefs exposed on the continental shelf during the glacial, and also from HMC ooids precipitated at the head of the Capricorn Channel at this time. Mass accumulation rates (MARs) are high (13.5 g/cm**/kyr) during the glacial and peak at ~20 g/cm** 3/kyr in the early transgression (16-14 ka BP). MARs then decline with further sea level rise as the Fitzroy River mouth retreats from the edge of the continental shelf after 13.5 ka BP. MARs remain low (4 g/cm**3/kyr) throughout the Holocene highstand. Data for the Holocene highstand indicate there is a reduction in siliciclastic influx to the Capricorn Channel with little quartz and feldspar below 350 mbsl. However, fine-grained fluvial sediments, presumably from the Fitzroy River, were still accumulating on the mid slope down to 2000 mbsl. The proportion of pelagic calcite in the core tops increases with water depth, while HMC decreases, and is present only in trace amounts in cores below 1500 mbsl. The difference in the percentage of HMC in the deeper cores between the glacial and Holocene may reflect differences in supply or deepening of the HMC lysocline during the glacial. Sediment accumulation rates also vary between cores in the Capricorn Channel and do not show the expected exponential decrease with depth. This may be due to intermediate or deep water currents reworking the sediments. It is also possible that present bathymetry data are too sparse to detect the potential role that submarine channels may play in the distribution and accumulation of sediments. Comparison of the Capricorn Channel MARs with those for other mixed carbonate/siliciclastic provinces from the northeast margin of Australia indicates that peak MARs in the early transgression in the Capricorn Channel precede those from the central GBR and south of Fraser Island. The difference in the timing of the carbonate and siliciclastic MAR peaks along the northeast margin is primarily related to differences in the physiography and climate of the provinces. The only common trend in the MARs from the northeast margin of Australia is the near synchronicity of the carbonate and siliciclastic MAR peaks in individual sediment cores, which supports a coeval sedimentation model. Category: geoscientificInformation Source: Supplement to: Bostock, Helen C; Opdyke, Bradley N; Gagan, Michael K; Fifield, L Keith (2009): Late Quaternary siliciclastic/carbonate sedimentation model for the Capricorn Channel, southern Great Barrier Reef province, Australia. Marine Geology, 257(1-4), 107-123, https://doi.org/10.1016/j.margeo.2008.11.003 Supplemental Information: Not Availble Coverage: Not Available
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  • X-radiographs (B, C and E) and photographs (A and D) of selected core sections. For symbols on the right side, see Table 3. Core locations are shown in Fig. 1B. ... Description and interpretation of sedimentary facies in core sediments ... Schematic diagrams of the depositional model in the Ulleung Interplain Gap and the adjacent areas during the late Quaternary. Cross sections cut through the South Korea Plateau and the Oki Bank. UIC=Ulleung Interplain Channel; UIG=Ulleung Interplain Gap. ... Summary of sedimentary logs and correlation of cores. For location of cores, see Figs. 1B, 7B, 9D and 10. Solid triangles indicate tephra layers of known eruption ages (Machida, 1999; Gorbarenko and Southon, 2000). U-Oki=Ulleung-Oki tephra (9.3 ka); AT=Aira-Tn tephra (24.7 ka). Open triangles represent AMS 14C dates. Asterisks in cores from the Ulleung Interplain Gap denote the layers of ‘laminated Mn-carbonate mud’ (facies CaM). For detailed acoustic characters of echo types (types I-2, I-3, II-1, III-2 and IV-3), see Table 4. ... Location, water depth and length of sediment cores
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  • cores... core... late... Sediment... Quaternary.
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