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  • Stages of inundation of the central Sunda Shelf. Shape and position of the certain morphological structures (Proto-Kapuas and Proto-Lupar Rivers, Natuna Islands, paleo-coastline) is partly hypothetical. Selected stages: (a) 30kyr—progradation of clinoforms and isolated sediment bodies (not shown). (b) 21calkyr bp—widespread exposure. Sediment bypassing through the central valley and deposition in the shoreline area. (c) 15kyrcal. bp—drowning and fill of the lowermost river course. Sedimentation focussed within the drowned part of the valley. Change from deltaic to estuarine conditions. (d) 14calkyr bp—rapid retreat of the river mouth and drowning of the valley during heavily accelerated sea-level rise. Sea-level approximately reached the margin of the interfluve plain (−70 m modern water depth in average) and a network of distributary channels replaced the former drainage system. (e) 13calkyr bp—complete submergence of the area. Valleys remain as depressions on the seafloor from this time onward and the shelf starved of terrigenous sediments. ... Schematised cross-section along the transect showing the depositional units and major surfaces (as defined in the text) based on the core data. For legend see Fig. 4. For abbreviations see Figs. 2 and 8. TST: terrestrial (black), mangrove (plant symbols), marine (lined; delta front to inner shelf facies). ... (a) Lithology of sediment cores. Depth in meters below sea surface (mbss). Core length is half of this scale. In the middle part of the transect, two different elevations are cored (inside the central valley and on the adjacent plains of the seafloor). Note that (i) some cores represent a group of cores containing the same facies succession merged for simplification and (ii) the distance between the cores is not equidistant in reality (cf. Fig. 1). (b) Correlation by discrimination of environmental units. The cores are normalized on the subaerial surface, which formed during the exposure around the last glacial maximum. ... Study area (a) and SO-115 transect on the Sunda Shelf (b); solid line: the transect presented here; (c) locations of sediment cores (black circles) with core numbers as used in Fig. 4. Position of the seismic records shown in Fig. 3 (grey rhombs): ‘x’ refers to profiles a and b, ‘o’ to profile c in Fig. 3. A-V, NS-V, PK-V, PL-V indicate the positions of the paleo-valleys of the Anambas, North Sunda, Kapuas and Lupar rivers (after Haile, 1969). ... Seismic profiles showing typical patterns of depositional units and erosional surfaces. SPGM and SLGM indicate the (subaerial) surfaces during the penultimate and the last glacial maximum; ts=transgressive surface, rs=ravinement surface (with indices 1–3 as used in the text). Arrows mark the positions of three cores. ... Late Quaternary
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  • Clay mineral assemblages correlate remarkably well during the last 85 ka, when both cores overlap. The arrow marks a conspicuous kaolinite peak in core MD03-2611, which could result from an independent discharge of a “Palaeo-River Vincent”, and is not found in core MD03-2607. The dashed line represents the composition of river clays from sample at Swan Reach (star in Fig. 2), closest to the modern river mouth. Oxygen isotope stages 1–6 are indicated, cold stages are shaded. ... late Quaternary... 3-D image of the Murray Canyons offshore South Australia to show the significantly incised topography of the canyons which continue down to approximately 5000 m. Note the vast expanse of the Lacepede Shelf that extends approximately down to the 120-m contour which would have been close to the edge of the continent during the Last Glacial Maximum (LGM). The location of the two cores mentioned in the text is shown by a star. Possible courses of the Palaeo-River Vincent and the Palaeo-Murray on the dry shelf during the LGM are shown. Map adapted from Hill and De Decker (2004). ... Oxygen isotopes, measured in the planktic foraminifera Globigerina bulloides, carbonate content and linear sedimentation rates, calculated from stratigraphic tie-points, show dramatic differences between cold periods and low sea levels and warm periods in core MD03-2607. The differences are less pronounced in core MD03-2611. Shaded sections represent cold isotope stages 2, 4 and 6. ... Detailed clay mineralogies and clay/silt-ratios for the last 20 ka for both cores. As ages are interpolated from 12 ka to the core top, assuming constant sedimentation rates, individual peaks may be offset by up to 1000 years between cores (e.g. the large deglacial illite peaks, P1 and P2). Some absolute dates, at least for one core, are needed to establish exact ages for the timing of events in the Holocene sequence. The arrow again marks a conspicuous kaolinite and quartz/feldspar peak at 14 ka in core MD03-2611, which we interpret as resulting from an independent discharge of a “Palaeo-River Vincent”.
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  • Ocean Sediment
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  • Changes in heavy metal distribution (mg g–1) with respect to clay content (%) of the sediments; unit 1 (+), unit 2 (x), unit 3 (▵) turbidites and coccoliths (·). ... Changes in heavy metal distribution (mg g–1) with respect to silt content (%) of the sediments; unit1 (+), unit2 (x), unit 3 (▵) turbidites and coccoliths (·). ... Sampled core lengths, water depths, locations and number of sub-samples taken from each core. ... Average heavy metal concentrations of different types of rocks and sediments of Black Sea. ... Locations of the cores.
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  • Late Quaternary... DEPTH, sediment/rock
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  • Mineral compositions of bulk sediments from core GS05 (Caspian Sea, southern basin). ... Map of the Caspian Sea with locations of core GS05 (present investigation) and of core GS04 (studied by Kuprin et al., 2003). ... (234U/238U) and (232Th/234U) activity ratios for bulk sediments, carbonates and clays from the core GS05 and for the Caspian Sea Water. *: Activity ratios determined by counting, the others have been measured by Thermo-Ionisation Mass Spectrometer (TIMS). ... Sr isotopic compositions, U/Th disequilibria (234U/238U) AR and (230Th/234U) AR, and Th/U elemental ratios (ppm/ppm) in the whole sediments, the carbonates (the three leaching procedures give the same results) and the clays. The variations are represented relative to depth of core GS05 from the Caspian Sea, with the representation of the four lithological sections (unit 1 = U1, transition zone = TZ, unit 2 = U2 and unit 3 = U3). WS = whole sediment and carbo = carbonate fraction. ... Sediment... Age (yr BP, not calibrated) and depth (cm) of sediments from the core GS05. The ages are summary in Table 2 (Chalié, 1997; Guichard F., pers. com.). The data allow proposing an age–depth model in three parts, following the lithological units. The points with circle correspond to ostracod analyses. ... a) Ca/Mg ratios versus Ca/Si ratios and b) Ca/Sr ratios versus Zr/Th ratios in the whole sediments (WS), in carbonates and in clays of the core GS05 from the Caspian Sea (unit 1 = U1, transition zone = TZ, unit 2 = U2 and unit 3 = U3). Fig. 7a suggests that the sediments could be explained by a simple mixing between two end members: a biogenic end member (represented by A, between the unit U2; the richest in carbonate and the carbonates) and a detrital end member (represented by B, close to the clays). But Fig. 5b suggests that the carbonates and the silicates have several origins and the sediment is not the simple result of mixing in different proportion of same carbonates and silicates.
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  • Late-Quaternary... A) Scatterplot of organic matter content (LOI 550) versus magnetic susceptibility (SI) for the Harding Lake composite core plotted by lithologic unit and B) surface sediments from core F-10, (7.1 m BML), A-12 (10.75 m BML), E-12 (15.91 m BML), B-10 (38.05 m BML), and C-10 (42.1 m BML). We utilize this conceptual model (i.e. changes in organic matter content and magnetic susceptibility) to interpret relative lake-level changes. Shallow water sediments are characterized by high magnetic susceptibility and low organic matter. Intermediate water depths are characterized by moderate magnetic susceptibility and organic matter content (eg. Unit 2 corresponds to core F-10, A-12, and E-12 sediment properties from 7 to 16 m water depths). Deep water sediments are characterized by low magnetic susceptibility and high organic matter content (eg. Unit 3-4 sediments correspond to core B-10 and C-10 sediment properties from 38 to 42 m water depths). ... A) Lake-level curve for Harding Lake inferred from core-transect data and sediment physical and geochemical properties. The dashed line between 14,000 and 9,400 yr BP represents uncertainty in the reconstruction due to lower (>16.8 m below modern level; BML) or fluctuating lake-levels during this time. B) Comparison with a lake-level reconstruction for Birch Lake, Alaska determined from seismic profiles and core transects (Abbott et al., 2000). C) July insolation (watts/m2) for 65° North (Berger and Loutre, 1991). D) Relative sea level data (Peltier and Fairbanks, 2006) and the ice-equivalent eustatic sea level history (smooth black line) (Waelbroeck et al., 2002). ... Magnetic susceptibility for cores C-10, D-10, and E-10 recovered from 42.1 m water depth showing the anomaly match used to construct the 422 cm composite depth scale. Gray bars indicate the major anomalies present in each core. ... Harding Lake composite core proxy data plotted against age in yr BP. Data also plotted against core depth (cm) for Unit 1 sediments spanning the Last Glacial Maximum. ... Composite core sedimentology and age-depth model developed from the AMS radiocarbon and 210Pb profile generated with the CLAM code for R software (Blaauw, 2010) with linear sedimentation rates (cm/yr). Gray squares indicate stratigraphically reversed dates that were rejected from the age model due to extremely small carbon yields and presumed modern carbon contamination. ... Lake sediment geochemistry... Alaska Quaternary Center, University of Alaska-Fairbanks, Fairbanks, AK 99775, USA
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  • Location of Lesina lagoon with position of the cores mentioned in this paper. ... Lithology, micropaleontology (foraminifers and ostracods), facies associations and sequence stratigraphic interpretation of cores S3 and S4. SB1: sequence boundary of the post-Tyrrhenian depositional sequence, TS1: post-Tyrrhenian transgressive surface, RS1: post-Tyrrhenian ravinement surface, SB2: sequence boundary of the Last Glacial to Holocene depositional sequence, TS2: Holocene transgressive surface, RS2: Holocene ravinement surface, LST: lowstand systems tract, TST: transgressive systems tract, HST: highstand systems tract, IVF: incised-valley fill. Position of the maximum flooding surfaces (MFS) is approximate. ... Representative S3 core (depth: 10.50–21.00 m) photographs of major facies associations and key surfaces for stratigraphic interpretation of the post-Tyrrhenian depositional sequence. A: alluvial plain, L: lagoon, T: transgressive sand sheet, M: shallow marine, P: swamp. Note the sequence boundary SB1, coinciding with the transgressive surface TS1, overlying a concretioned level of alluvial plain deposits and the ravinement surface RS1 separating the transgressive deposits (lagoon facies association and transgressive sand sheet). ... S4 core photographs (depth: 0.00–21.00 m) depicting the Last Glacial to Holocene depositional sequence. a) Note the transgressive surface TS2 at the base of lagoon (facies association L) and back-barrier deposits (facies association B) of Holocene age, and the ravinement surface RS2 underlying regressive beach-ridge deposits (facies association S). b) This photo shows the thick fluvial-incised sands (facies association C) overlying lagoon deposits of post-Tyrrhenian age by means of an erosion surface which correspond to the sequence boundary SB2 of the Last Glacial to Holocene depositional sequence. ... Late Quaternary... Schematic reconstruction of the subsurface facies architecture of the Lesina lagoon during Late Quaternary. Abbreviations are defined in the text and in previous figures.
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  • Pollen and organic-walled dinoflagellate cysts datasets on marine sediment core GeoB6211-2 off southern Brazil, which was collected during RV Meteor cruise M46/2 in the Argentine Basin in 1999 (Schulz et al., 2001; Wefer et al., 2001).
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  • AMS radiocarbon dates obtained from bulk organic carbon of sediments recovered in vibrocores from the northern Larsen continental shelf ... Location map of the northern Larsen continental shelf NE Antarctic Peninsula showing the geography of the region and bathymetry of the continental shelf. Light grey areas denote regions of the continental shelf shallower than 400m. Boxed areas on the map refer to detailed EM120 swath bathymetric maps in Figs. 2, 3, 5, 6 and 7, and sediment cores in Figs. 10–13. ... (a) EM120 shaded relief image of Southern Prince Gustav Channel and adjacent shelf (Grid cell size 50m×50m) showing subtle to well-developed highly attenuated bedforms (mega-scale glacial lineations) and crudely streamlined bedforms. Sediment cores recovered from the region are indicated. (b) Detailed image of the shelf south of Prince Gustav Channel showing very subtle highly attenuated glacial lineations, crudely streamlined bedforms and grounding-zone. A prominent ship's artefact trends NNW–SSE across the swath image. Acoustic artefacts parallel to the NNW–SSE ship tracks are superimposed on the NW–SE glacial features. (c) TOPAS acoustic record from the shelf south of Prince Gustav Channel (profile located in Fig. 5a).... (a) EM120 shaded relief image (Grid cell size 50m×50m) showing glacial bedforms across the Larsen-A shelf. Gouges orientated SW–NE are present on the shallow shelf south/southeast of Greenpeace Trough. Sediment cores recovered from the region are indicated. White arrows indicate grounded ice flow direction. Detailed images include: (b) highly attenuated lineations and drumlins in Greenpreace Trough, (c) short irregular bedrock-cored drumlins at the head of Greenpeace Trough and (d) TOPAS acoustic record from Greenpeace Trough illustrating a typical sub-bottom sedimentary record of a drumlin and inter-drumlin area of the trough floor. ... Lithofacies in cores from the northern Larsen continental shelf (after Eyles et al., 1983) ... (a) EM120 shaded relief image of outer Robertson Trough and shallow outer shelf banks (Grid cell size 50m×50m) showing; (b–d) Streamlined subglacial lineations are mainly oriented SW–NE but are cross-cut by WNW-ESE lineations along the margins in water depths Sediment cores recovered from the region are indicated.
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