Contributors: Moy, Christopher M, Howard, William R, Gagan, Michael K

Date: 2006-10-29

late Quaternary sediment cores from the South Tasman Rise...Sediment cores MD972106 (45° 09' S, 146° 17' E, 3310 m water depth) and...Quaternary Science, 21(7), 763-777, https://doi.org/10.1002/jqs.1067 ...Late Quaternary palaeoceanography of the Circumpolar Deep Water from the...sediment cores from the South Tasman Rise (STR) to reconstruct deep- water...Late Quaternary palaeoceanography of the Circumpolar Deep Water from the ... Abstract: We use sediment cores from the South Tasman Rise (STR) to reconstruct deep- water circulation in the southwest Pacific sector of the Southern Ocean. Sediment cores MD972106 (45° 09' S, 146° 17' E, 3310 m water depth) and GC34 (45° 06' S, 147° 45' E, 4002 m water depth) preserve records covering the last 160 kyr, with chronology controlled by calibrated accelerator mass spectrometry radiocarbon dates and benthic foraminiferal d18O tied to SPECMAP. The STR benthic foraminiferal d13C records provide new d13C values for Southern Ocean deep water spanning the last 160 kyr at sites unlikely to be affected by variations in productivity. The records establish that glacial benthic foraminifera (Cibicidoides spp.) d13C values are lower relative to interglacial values and are comparable to previous glacial benthic d13C records in the Indian and Pacific sectors of the Southern Ocean. Comparisons of the benthic foraminiferal d13C time series at the STR are made with the equatorial Pacific (V19-30 and Site 846) and the equatorial Atlantic (GeoB1115). The similarity of benthic d13C records at the STR to the equatorial Pacific suggest the Southern Ocean deep-water mass closely tracked those of the deep Pacific, and the presence of a d13C gradient between the STR and the equatorial Atlantic suggests there was continual production of northern source deep water over the past 160 kyr. Category: geoscientificInformation Source: Supplement to: Moy, Christopher M; Howard, William R; Gagan, Michael K (2006): Late Quaternary palaeoceanography of the Circumpolar Deep Water from the South Tasman Rise. Journal of Quaternary Science, 21(7), 763-777, https://doi.org/10.1002/jqs.1067 Supplemental Information: Not Availble Coverage: Not Available

Contributors: Rossignol-Strick, Martine, Duzer, Daniele

Date: 1979-11-15

late Quaternary cores off Senegal shows a juxtaposition of Mediterranean...Late Quaternary sediment cores off West Africa...core 47. Cosmopolitan taxa dominate the assemblage and only a few species...core. Dinoflagellate cysts display a tropical assemblage with mostly estuarine...Late Quaternary pollen and dinoflagellate cysts in marine cores off West...late Quaternary cores off Senegal shows a juxtaposition of Mediterranean...cores. Category: geoscientificInformation Source: Supplement to: Rossignol-Strick...Late Quaternary pollen and dinoflagellate cysts in marine cores off West ... Abstract: The pollen record of three marine late Quaternary cores off Senegal shows a juxtaposition of Mediterranean, Northern Saharan, Central Saharan elements, which are considered transported by the trade winds from a winter-rainfall area, and Sahelian, Soudanese, Soudano-Guinean elements, considered transported both by winds and mostly by the Senegal River, and coming from the monsoonal, summer tropical rainfall area of southern West Africa. Littoral vegetation is either the edaphically dry and saline Chenopodiaceae from sebkhas at the time of the main regression, or the warm tropical humid mangrove with Rhizophora during the humid optimum period. Four stratigraphic zones reflect, from basis to top: Zone 4. A semi-arid period with a balanced pollen input. Zone 3. A very arid period with the disappearance of monsoonal pollen, probably from the disappearance of the Senegal River, a very saline littoral plain with Chenopodiaceae, a larger input of northern Saharan pollen from intensified trade winds. Zone 2. A quite humid period, much more so than today, very suddenly established, with a northward extension of the monsoonal areas, a rich littoral mangrove, and weakening of the trade winds. Zone l. A slow and steady evolution toward the present semi-humid conditions with regression of the mangrove, and of the monsoonal areas toward the south. Tentative datations and correlations with the Tchad area suggested: zone 4: 22,500 to 19,000 years BP; zone 3: 19,000 to 12,500 years BP; zone 2: 12,500 to 5,500 years BP; zone 1: 5,500 years BP to top of core. Dinoflagellate cysts display a tropical assemblage with mostly estuarine neritic elements and also a weak oceanic component, mostly in the lower slope core 47. Cosmopolitan taxa dominate the assemblage and only a few species point to more specialized environments. Quantitative variations of the assemblage are the basis of stratigraphy which is not similar to the pollen stratigraphy, and an inshore-outshore gradient has to be taken into account to correlate the three cores. Category: geoscientificInformation Source: Supplement to: Rossignol-Strick, Martine; Duzer, Daniele (1979): Late Quaternary pollen and dinoflagellate cysts in marine cores off West Africa. Meteor Forschungsergebnisse, Deutsche Forschungsgemeinschaft, Reihe C Geologie und Geophysik, Gebrüder Bornträger, Berlin, Stuttgart, C30, 1-14 Supplemental Information: Not Availble Coverage: EVENT LABEL: * LATITUDE: 15.443333 * LONGITUDE: -17.306667 * DATE/TIME: 1971-01-01T00:00:00 * ELEVATION: -625.0 m * LOCATION: East Atlantic * CAMPAIGN: M25 * BASIS: Meteor (1964) * DEVICE: Kasten corer EVENT LABEL: * LATITUDE: 15.480000 * LONGITUDE: -17.360000 * DATE/TIME: 1971-11-17T00:00:00 * ELEVATION: -945.0 m * Recovery: 5.5 m * LOCATION: East Atlantic * CAMPAIGN: M25 * BASIS: Meteor (1964) * DEVICE: Kasten corer EVENT LABEL: * LATITUDE: 15.825000 * LONGITUDE: -17.861667 * DATE/TIME: 1971-11-17T00:00:00 * ELEVATION: -2576.0 m * Recovery: 6 m * LOCATION: East Atlantic * CAMPAIGN: M25 * BASIS: Meteor (1964) * DEVICE: Kasten corer

Contributors: Wells, Patricia, Wells, Graeme, Cali, Joe, Chivas, Allan R

Date: 1994-02-18

Core...Late Quaternary sediments of core BMR96GC21 in the southeast Indian Ocean ... Abstract: Not Available Category: geoscientificInformation Source: Not Available Supplemental Information: Not Availble Coverage: EVENT LABEL: * LATITUDE: -23.772167 * LONGITUDE: 108.500667 * ELEVATION: -2100.0 m * Recovery: 1.8 m * LOCATION: Southeast Indian Ocean * DEVICE: Core

Contributors: Gerhardt, Sabine, Groth, H, Rühlemann, Carsten, Henrich, Rüdiger

Date: 2000-01-29

Late Quaternary: Reconstruction of Budget and Currents...Late Quaternary: Reconstruction of Budget and Currents...sediment cores from the Brazilian Continental Slope...late Quaternary sediment cores on the Brazilian Continental Slope: implications...late Quaternary records of aragonite preservation determined for sediment...late Quaternary sediment cores on the Brazilian Continental Slope: implications...cores recovered on the Brazilian Continental Slope (1790-2585 m water ...late Quaternary records of aragonite preservation determined for sediment ... Abstract: We present late Quaternary records of aragonite preservation determined for sediment cores recovered on the Brazilian Continental Slope (1790-2585 m water depth) where North Atlantic Deep Water (NADW) dominates at present. We have used various indirect dissolution proxies (carbonate content, aragonite/calcite contents, and sand percentages) as well as gastropodal abundances and fragmentation of Limacina inflata to determine the state of aragonite preservation. In addition, microscopic investigations of the dissolution susceptibility of three Limacina species yielded the Limacina Dissolution Index which correlates well with most of the other proxies. Excellent preservation of aragonite was found in the Holocene section, whereas aragonite dissolution gradually increases downcore. This general pattern is attributed to an overall increase in aragonite corrosiveness of pore waters. Overprinted on this early diagenetic trend are high-frequency fluctuations of aragonite preservation, which may be related to climatically induced variations of intermediate water masses. Category: geoscientificInformation Source: Supplement to: Gerhardt, Sabine; Groth, H; Rühlemann, Carsten; Henrich, Rüdiger (2000): Aragonite preservation in late Quaternary sediment cores on the Brazilian Continental Slope: implications for intermediate water circulation. International Journal of Earth Sciences, 88(4), 607-618, https://doi.org/10.1007/s005310050291 Supplemental Information: Not Availble Coverage: EVENT LABEL: * LATITUDE: -8.531667 * LONGITUDE: -34.023333 * DATE/TIME: 1993-03-22T00:00:00 * ELEVATION: -2080.0 m * Recovery: 0.43 m * LOCATION: Brazil Basin * CAMPAIGN: M23/3 * BASIS: Meteor (1986) * DEVICE: MultiCorer EVENT LABEL: * LATITUDE: -8.528333 * LONGITUDE: -34.021667 * DATE/TIME: 1993-03-22T00:00:00 * ELEVATION: -2072.0 m * Recovery: 8.97 m * LOCATION: Brazil Basin * CAMPAIGN: M23/3 * BASIS: Meteor (1986) * DEVICE: Gravity corer (Kiel type) EVENT LABEL: * LATITUDE: -8.573333 * LONGITUDE: -34.345000 * DATE/TIME: 1993-03-22T00:00:00 * ELEVATION: -1790.0 m * Recovery: 0.45 m * LOCATION: Brazil Basin * CAMPAIGN: M23/3 * BASIS: Meteor (1986) * DEVICE: MultiCorer EVENT LABEL: * LATITUDE: -8.735000 * LONGITUDE: -34.135000 * DATE/TIME: 1993-03-23T00:00:00 * ELEVATION: -2585.0 m * Recovery: 0.35 m * LOCATION: Brazil Basin * CAMPAIGN: M23/3 * BASIS: Meteor (1986) * DEVICE: MultiCorer

Contributors: Bostock, Helen C, Opdyke, Bradley N, Gagan, Michael K, Fifield, L Keith

Date: 2009-04-24

sediment influenced all the cores down to 2000 mbsl. The percentages of...Late Quaternary siliciclastic/carbonate sedimentation in the Cabricorn...cores decreased with water depth, while the percentage of clay increased...core tops increases with water depth, while HMC decreases, and is present...sediment cores, which supports a coeval sedimentation model. Category...Late Quaternary siliciclastic/carbonate sedimentation model for the Capricorn...Sediment accumulation rates also vary between cores in the Capricorn Channel...sediment cores, which supports a coeval sedimentation model. Category...Late Quaternary siliciclastic/carbonate sedimentation model for the Capricorn ... 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

Contributors: Patricia Wells

Date: 1994-01-01

Late Quaternary sediments of core BMR96GC21 in the southeast Indian Ocean ... 398 occurrences

Contributors: Müller, Peter J, Cepek, Martin, Ruhland, Götz, Schneider, Ralph R

Date: 1997-10-19

Late Quaternary: Reconstruction of Budget and Currents...late Quaternary periods when this species was scarce or absent because...Late Quaternary: Reconstruction of Budget and Currents...late Quaternary coccolith datum levels: Validation by oxygen isotopes....late Quaternary sediment core from the Walvis Ridge and compared the results...Quaternary sediments may be subject to bias if algae with different temperature...late Quaternary sediments from the Walvis Ridge: Implications for the ...late Quaternary sediments from the Walvis Ridge: Implications for the ...late Quaternary sediment core from the Walvis Ridge and compared the results...late Quaternary coccolith datum levels: Validation by oxygen isotopes....core record while the coccolithophorid study was confined to the last ...late Quaternary sediments from the Walvis Ridge...late Quaternary periods when this species was scarce or absent because ... Abstract: Sea surface temperatures (SSTs) derived from the alkenone UK'37) record of Quaternary sediments may be subject to bias if algae with different temperature sensitivities have contributed to the sedimentary alkenone record. The alkenone-derived SST records are usually based on a UK'37-temperature relationship which was measured in culture experiments using the coccolithophorid Emiliania huxleyi (F.G. Prahl, L.A. Muehlhausen and D.L. Zahnle, 1988. Further evaluation of long-chain alkenones as indicators of paleoceanographic conditions. Geochim. Cosmochim. Acta 52, 2303-2310). To assess possible effects of past species changes on the UK'37-temperature signal, we have analyzed long-chain alkenones and coccolithophorids in a late Quaternary sediment core from the Walvis Ridge and compared the results to SST estimates extracted from the d18O record of the planktonic foraminifer Globigerinoides ruber. Alkenones and isotopes were determined over the entire 400-kyr core record while the coccolithophorid study was confined to the last 200 kyr when the most pronounced changes in alkenone content occurred. Throughout oxygen-isotope stages 6 and 5, species of the genus Gephyrocapsa were the predominating coccolithophorids. E. huxleyi began to increase systematically in relative abundance since the stage 5/4 transition, became dominant over Gephyrocapsa spp. during stage 3 and reached the highest abundances in the Holocene. Carbon-normalized alkenone concentrations are inversely related to the relative abundances of E. huxleyi, and directly related to that of Gephyrocapsa spp., suggesting that species of this genus were the principal alkenone contributors to the sediments. Nevertheless, SST values obtained from the UK'37-temperature relationship for E. huxleyi compare favourably to the isotope-derived temperatures. The recently reported UK'37-temperature relationship for a single strain of Gephyrocapsa oceanica (J.K. Volkman. S.M. Barrett, S.I. Blackburn and E.L. Sikes, 1995. Alkenones in Gephyrocapsa oceanica: Implications for studies of paleoclimate. Geochim. Cosmochim. Acta 59, 513-520) produces unrealistically high SST values indicating that the temperature response of the examined strain is not typical for the genus Gephyrocapsa. This is supported by the C37:C38, alkenone ratios of the sediments which are comparable to average ratios reported for E. huxleyi, but significantly higher than for the G. oceanica strain. Most notably, the general accordance of the alkenone characteristics between sediments and E. huxleyi persists through stages 8 to 5 and even in times that predate the first appearance of this species (268 ka; H.R. Thierstein, K.R. Geitzenauer and B. Molfino, 1977. Global synchroneity of late Quaternary coccolith datum levels: Validation by oxygen isotopes. Geology 5, 400-404). Our results suggest that UK'37-temperature relationships based on E. huxleyi produce reasonable paleo-SST estimates even for late Quaternary periods when this species was scarce or absent because other alkenone-synthesizing algae, e.g. of the genus Gephyrocapsa. Category: geoscientificInformation Source: Supplement to: Müller, Peter J; Cepek, Martin; Ruhland, Götz; Schneider, Ralph R (1997): Alkenone and coccolithophorid species changes in late Quaternary sediments from the Walvis Ridge: Implications for the alkenone paleotemperature method. Palaeogeography, Palaeoclimatology, Palaeoecology, 135(1-4), 71-96, https://doi.org/10.1016/S0031-0182(97)00018-7 Supplemental Information: Not Availble Coverage: EVENT LABEL: * LATITUDE: -20.104000 * LONGITUDE: 9.185833 * DATE/TIME: 1988-03-02T00:00:00 * ELEVATION: -2209.0 m * Penetration: 12 m * Recovery: 10.79 m * LOCATION: Walvis Ridge, Southeast Atlantic Ocean * CAMPAIGN: M6/6 * BASIS: Meteor (1986) * DEVICE: Gravity corer (Kiel type)

Contributors: Lamy, Frank, Klump, Jens, Hebbeln, Dierk, Wefer, Gerold

Date: 2000-08-16

cores and from North Atlantic sediments. Besides showing dominantly precession-driven...sediments, reveal a high-frequency variability of the position of the ...Late Quaternary rapid climate change in northern Chile. Terra Nova, 12...sediments from the Chilean continental slope off the southern border of...Late Quaternary rapid climate change in northern Chile. Terra Nova, 12...Late Quaternary geochemical record of sediment core GeoB3375-1 ... Abstract: Analyses of terrigenous sediments from the Chilean continental slope off the southern border of the Atacama desert (27.5°S), focusing on illite crystallinity and the Fe:Al ratio of the sediments, reveal a high-frequency variability of the position of the Southern Westerlies, which is very similar to the coeval short-term climatic events known from Greenland ice cores and from North Atlantic sediments. Besides showing dominantly precession-driven variability in precipitation over the Andes, these analyses also reveal rapid changes in weathering intensity along the Chilean Coastal Range during the last 80,000 years. These rapid changes occur at much shorter timescales than the 19-100 kyr orbital forcing of the Milankovitch cycles. Category: geoscientificInformation Source: Supplement to: Lamy, Frank; Klump, Jens; Hebbeln, Dierk; Wefer, Gerold (2000): Late Quaternary rapid climate change in northern Chile. Terra Nova, 12, 8-13, https://doi.org/10.1046/j.1365-3121.2000.00265.x Supplemental Information: Not Availble Coverage: EVENT LABEL: * LATITUDE: -27.466667 * LONGITUDE: -71.251667 * DATE/TIME: 1995-06-07T00:00:00 * ELEVATION: -1947.0 m * Recovery: 4.89 m * LOCATION: South-East Pacific * CAMPAIGN: SO102/2 * BASIS: Sonne * DEVICE: Gravity corer (Kiel type)

Contributors: Ehrmann, Werner, Seidel, Martin, Schmiedl, Gerhard

Date: 2013-04-27

sediments in the source areas. Category: geoscientificInformation Source...sediment core GeoTü SL143...late Quaternary sediment core from the central Aegean Sea. The record ...Late Quaternary North African humid periods documented in the clay mineral...Late Quaternary North African humid periods documented in the clay mineral...sediments. Global and Planetary Change, 107, 186-195, https://doi.org/...late Quaternary sediment core from the central Aegean Sea. The record ... Abstract: The ratio between the clay minerals kaolinite and chlorite has been investigated in high resolution in a late Quaternary sediment core from the central Aegean Sea. The record spans the last ca. 105 ka. The kaolinite/chlorite ratio was used to reconstruct the fine-grained aeolian dust influx from the North African deserts, mainly derived from desiccated lake depressions. It therewith can be used as a proxy for wind activity, aridity and vegetation cover in the source area. The data document three major humid phases in North Africa bracketing the formation of sapropel layers S4, S3 and S1. They occur at >105-95 ka, 83.5-72 ka and 14-2 ka. The first two phases are characterised by relatively abrupt lower and upper boundaries suggesting a non-linear response of vegetation to precipitation, with critical hydrological thresholds. In contrast, the onset and termination of the last humid period were more gradual. Highest kaolinite/chlorite ratios indicating strongest aeolian transport and aridity occur during Marine Isotope Stage (MIS) 5b, at ca. 95-84 ka. The long-term decrease in kaolinite/chlorite ratios during the last glacial period indicates a gradual decline of deflatable lake sediments in the source areas. Category: geoscientificInformation Source: Supplement to: Ehrmann, Werner; Seidel, Martin; Schmiedl, Gerhard (2013): Dynamics of Late Quaternary North African humid periods documented in the clay mineral record of central Aegean Sea sediments. Global and Planetary Change, 107, 186-195, https://doi.org/10.1016/j.gloplacha.2013.05.010 Supplemental Information: Not Availble Coverage: EVENT LABEL: (GeoTü SL143) * LATITUDE: 38.261830 * LONGITUDE: 25.103170 * ELEVATION: -665.0 m * LOCATION: Aegean Sea * DEVICE: Gravity corer (Kiel type)

Contributors: Wells, Patricia, Wells, Graeme, Cali, Joe, Chivas, Allan R

Date: 1994-02-18

Core...Late Quaternary sediments of core BMR96GC21 in the southeast Indian Ocean ... Abstract: Not Available Category: geoscientificInformation Source: Not Available Supplemental Information: Not Availble Coverage: EVENT LABEL: * LATITUDE: -23.772167 * LONGITUDE: 108.500667 * ELEVATION: -2100.0 m * Recovery: 1.8 m * LOCATION: Southeast Indian Ocean * DEVICE: Core