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Par Collection Par Auteur Par Date Par Sujet Par Titre
  • Late Quaternary climate and hydrology of tropical South America inferred from an isotopic and chemical model of Lake Titicaca, Bolivia and Peru
  • Bolivia ; Climatic variation ; Geochemistry ; Isotope analysis ; Lake ; Lake level ; Model ; Oxygen 18 ; Palaeoclimate ; Palaeohydrology ; Peru ; Quaternary ; Salinity ; South America ; Tropical zone
  • A simple mass balance model provides insight into the hydrologic, isotopic, and chemical responses of Lake Titicaca to past climatic changes. Latest Pleistocene climate of the Altiplano is assumed to have been 20% wetter and 5°C colder than today
  • , based on previous modelling. The simulation of lacustrine change since 15,000 cal yr B.P. is forced by these modeled climate changes. Here the AA. employ an isotopic and chemical model in order to assess the magnitude of hydrologic changes required
  • to produce the observed lake-level changes and to investigate the expected isotopic and chemical response of the lake to water balance changes.
  • 2001
  • Stable isotope stratigraphy of a late last interglacial speleothem from Rana, northern Norway
  • Climate fluctuation ; Interglacial ; Isotope dating ; Norway ; Oxygen 18 ; Palaeo-environment ; Palaeoclimatology ; Quaternary ; Speleothem ; Stratigraphy ; Uranium
  • The AA. present high-resolution stable oxygen and carbon isotope records from a speleothem from northern Norway, giving details on climatic fluctuations from the late last interglacial and the last interglacial-glacial transition, as well
  • 2001
  • The origin of sulphates : an example of sulphur isotopic applications
  • Arid area ; Biogeochemical cycle ; Cold area ; Evaporite ; Geochemistry ; Gypsum ; Human impact ; Isotope analysis ; Palaeo-environment ; Pollution
  • This review is concerned with the technique of stable isotope analysis (δS 34) as a means of studying the sulphur cycle with particular emphasis on the formation of sulphate evaporites such as gypsum. Gypsum is found in all settings that promote
  • 2001
  • Accumulation glaciaire ; Densité ; Glaciologie ; Groenland ; Isotope ; Névé ; Oxygène ; Radioactivité ; Température ; Vitesse
  • Firn ; Glacial deposit ; Glaciology ; Greenland ; Isotope ; Oxygen ; Radioactivity ; Temperature
  • 2001
  • Late Quaternary vegetation dynamics in the southern Amazon Basin inferred from carbon isotopes in soil organic matter
  • Amazon Basin ; C 14 dating ; Carbon ; Climatic variation ; Forest ; Holocene ; Isotope analysis ; Palaeo-environment ; Quaternary ; Savanna ; South America ; Vegetation dynamics
  • Carbon isotopes of soil organic matter (SOM) were used to evaluate and establish the chronology of the vegetation dynamics of an ecosystem presently composed of savannas surrounded by forests. The study was carried out on a 200-km transect along
  • 2001
  • Carbon-isotope, diatom, and pollen evidence for Late Holocene salinity change in a brackish marsh in the San Francisco estuary
  • Analysis of diatoms, pollen, and the carbon-isotopic composition of a sediment core from a brackish marsh in the northern part of the San Francisco Estuary has provided a paleosalinity record that covers the past 3000 yr. Changes in marsh
  • 2001
  • Argentina ; C 14 dating ; Deuterium ; Isotope analysis ; Model ; Moss ; Palaeo-ecology ; Palaeoclimate ; Patagonia ; Peat bog ; Pollen ; Quaternary
  • Pollen assemblage changes and stable hydrogen isotope analysis of mosses from a bog in Tierra del Fuego, Argentina, provided independent proxies for reconstructing changes in effective moisture and temperature over the past 16,000 cal yr B.P
  • . A deterministic model was used to reconstruct the stable hydrogen isotope composition of meteoric water from the D/H ratios of bog mosses over the last 16,000 years.
  • 2001
  • Holocene climate inferred from oxygen isotope ratios in lake sediments, central Brooks Range, Alaska
  • Analyses of sediment cores from two lakes in the central Brooks Range provide temperature and moisture balance information for the past 8500 cal yr at century-scale resolution. Two methods of oxygen isotope analysis are used to reconstruct past
  • 2001
  • Raised coral terraces at Malakula, Vanuatu, southwest Pacific, indicate high sea level during marine isotope stage 3
  • were analysed by the thermal inonization mass spectrometry (TIMS) U/Th dating technique, yielding information on sea levels during late marine isotope stage 3 and early stage 4. The findings are in good agreement with sea-level estimates from raised
  • 2001
  • Carbon ; Climatic index ; Germany ; Isotope analysis ; Loess ; Methodology ; Organic materials ; Palaeo-environment ; Precipitation ; Rhine ; Valley
  • High-resolution paleoprecipitation reconstructions for the last glaciation based on the isotopic record organic matter in loess from Nussloch (Rhine Valley, Germany) are consistent with paleoprecipitation inferred from peat in the same area using
  • 2001
  • Sea level fluctuations during oxygen isotope stage 5 : new data from fossil shorelines in the Sorrento Peninsula (Southern Italy)
  • 2001
  • The AA. compare the Taylor Dome oxygen isotope record with the isotope records of Vostok and Byrd Station, Antarctica, and GISP2, Greenland. The features of the Taylor Dome δ O 18 record suggest that climate changes were essentially synchronous
  • 2001
  • Alaska ; Geochronology ; Glaciation ; Glacier advance ; Isotope dating ; Moraine ; Palaeo-environment ; Pleistocene ; Thermoluminescence
  • glaciation early during the late Pleistocene, in contrast to the deep-sea isotopic record of global ice volume.
  • 2001
  • Evidence for millennial-scale climate change during marine isotope stages 2 and 3 at Little Lake, Western Oregon, USA
  • Pollen and geochemical data from Little Lake, western Oregon, suggest several patterns of millenial-scale environmental change during marine isotope stage (MIS)2 (14,100-27,600 cal yr B.P.) and the latter part of MIS3 (27,600-42,500 cal yr B.P
  • 2001
  • Australia ; Chronostratigraphy ; Climatic variation ; Dating ; Glaciation ; Glacier advance ; Isotope analysis ; Moraine ; Mountain ; New South Wales ; Pleistocene ; Quaternary
  • 2001
  • Canada ; Coastal dune ; Coastal environment ; Earth surface processes ; Forest soil ; Isotope analysis ; Ontario ; Sand ; Soil properties ; Stratigraphy ; Tracer
  • 2001
  • Antarctic Ocean ; Climatic variation ; Diatom ; Foraminifera ; Holocene ; Isotope analysis ; Oxygen 18 ; Palaeoclimatology ; Palaeogeography ; Sea ice ; South Atlantic Ocean ; Surface temperature
  • high sedimentation rate in the Holocene and its position relative to strong hydrographic gradients in the subantarctic South Atlantic. The AA. measured multiple proxies including oxygen isotopes of diatoms and foraminifera, February sea surface
  • 2001
  • Aerial photography ; Bank erosion ; Channel geometry ; Flood ; Floodplain ; France ; Garonne ; Isotope analysis ; Riparian vegetation ; Sedimentation rate ; Stream ; Suspended load ; Twentieth Century
  • 2001
  • Aerial photography ; Chile ; Geographical information system ; Isotope dating ; Lacustrine sediment ; Land use ; Palynology ; Photointerpretation ; Sediment budget
  • 2001
  • Archaeology ; Australia ; C 14 dating ; Charcoal ; Dating ; Geochemistry ; Human occupation ; Isotope dating ; Quaternary ; Thermoluminescence
  • 2001