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  • A detailed 31,000-year record of climate and vegetation change, from the isotope geochemistry of two New Zealand speleothems
  • Carbon ; Cave ; Glaciation ; Isotope analysis ; New Zealand ; Oxygen 18 ; Palaeo-environment ; Palaeobotany ; Palaeoclimate ; Pleistocene ; Quaternary ; South Island
  • This paper presents continuous high-resolution stable isotope records of environmental change in New Zealand from speleothems that grew over the last 31,000 yr. Oxygen isotope variation in these speleothems primarily represents changes
  • in the meteoric waters falling above the caves, possibly responding to latitudinal changes in the position of the Subtropical Front in the Tasman sea. Carbone isotope variations in the speleothems record changes in forest productivity, closely matching existing
  • 1998
  • Strontium isotope ratios in streams and the effect of flow rate in relation to weathering in catchments
  • Discharge ; Geochemistry ; Isotope analysis ; Scotland ; Strontium ; Tracer ; United Kingdom ; Water erosion ; Watershed ; Weathering
  • To provide more detail information on the effect of flow rate on strontium isotope ratios, the Sr 87/Sr 86 ratio was measured in streamwater samples taken at low and high flow rates and also in samples taken at four and eight hourly intervals during
  • 1998
  • Strontium isotope ages of the marine Merced Formation, near San Francisco, California
  • California ; Foraminifera ; Glacio eustatic change ; Isotope analysis ; Pleistocene ; Quaternary ; Sea level ; United States of America
  • The strontium isotopic compositions of foraminifers were determined to refine the age of coastal sediments of the Merced Formation and to evaluate the relation between transgressive-regressive cycles and Pleistocene glacio-eustatic sea-level
  • 1998
  • Do stable isotope data from calcrete record late Pleistocene monsoonal climate variation in the Thar Desert of India?
  • Calcrete ; Carbon ; Geochemistry ; India ; Isotope analysis ; Monsoon ; Oxygen 18 ; Palaeoclimate ; Pedogenesis ; Pleistocene ; Quaternary ; Rajasthan
  • In this paper, the AA. attempt to construct a detailed terrestrial late Pleistocene climatic record in India by studying oxygen and carbon stable isotopes in pedogenic calcrete from the Thar Desert. The nearly continuous calcrete record in eolian
  • intervals and the chronology from thermoluminescence, infrared- and green-light-stimulated luminescence dates give a good opportunity to examine the isotopic data for paleoclimatic variability and relate this to other marine and terrestrial records.
  • 1998
  • Isotopic fingerprints of paleoclimates during the last 30,000 years in deep confined groundwaters of southern India
  • This paper reports results, related to paleoclimatic events during the last 30,000 years, obtained from isotope studies of deep confined groundwater of southern India. This is the first study of the confined groundwaters of southern India
  • 1998
  • Late Pleistocene C4 plant dominance and summer rainfall in the southwestern United States from isotopic study of herbivore teeth
  • Arizona ; California ; Global change ; Isotope analysis ; Model ; Monsoon ; Nevada ; New Mexico ; Palaeo-environment ; Palaeoclimatology ; Pleistocene ; Precipitation ; Quaternary ; United States of America
  • Patterns of climate and C4 plant abundance in the southwestern United States during the last glaciation were evaluated from isotopic study of herbivore tooth enamel. The primary objectives were to : delineate synoptic patterns in late Pleistocene C4
  • 1998
  • East Asian monsoon climates and Gobi dynamics in marine isotope stages 4 and 3
  • factors during marine isotope stages (MIS) 4 and 3. The magnetic susceptibility data are compared with other climatic proxy data to improve the well-publicized reconstruction of the past monsoons. The improved reconstruction is then used to see whether
  • 1998
  • Evidence from Lake Baikal for siberian glaciation during oxygen-isotope substage 5d
  • The paleoclimatic record from bottom sediments of Lake Baikal (eastern Siberia) reveals new evidence for an abrupt and intense glaciation during the initial part of the last interglacial period (isotope substage 5d). This glaciation lasted about
  • 1998
  • Isotopic composition of ice cores and meltwater from Upper Fremont Glacier and Galena Creek rock glacier, Wyoming
  • Geochemistry ; Glacial ablation ; Glacier ; Isotope analysis ; Meltwater ; Rock glacier ; Spatial variation ; United States of America ; Wyoming
  • 1998
  • Atmospheric circulation ; China ; Continentality ; Evaporation ; Isotope analysis ; Monsoon ; Oxygen 18 ; Precipitation ; Spatial variation ; Temperature
  • of different regions are of certain divergence, which is related to the stable isotopic fractionations of the 2 processes, the evaporation of origins and the precipitating of vapor.
  • 1998
  • Chevron ridges and runup deposits in the Bahamas from storms late in oxygen-isotope substage 5e
  • 1998
  • Isotopes radioactifs artificiels dans les mers de l'Arctique occidental au cours de la période 1972-1996
  • Arctique océan ; Barents mer ; Déchet radioactif ; Eau de mer ; Isotope ; Kara mer ; Mer Blanche ; Mer de Norvège ; Mer du Groenland ; Radioactivité ; Sédiment marin ; Zone froide
  • Arctic Ocean ; Barents Sea ; Cold area ; Groenland Sea ; Isotope ; Marine sediment ; Norwegian Sea ; Radioactive waste ; Radioactivity ; Sea water ; White Sea
  • 1998
  • Climate ; Evaporation ; Groundwater ; Hydrochemistry ; Isotope analysis ; Precipitation ; Salinisation ; Sri Lanka ; Topography ; Water ; Water cycle ; Water quality ; Watershed
  • whithin a relatively short distance. Sri Lanka is spatially divided into a dry zone, an intermediate zone and a wet zone, and there are rainy and dry seasons. Zonation of groundwater quality was made clear using field investigation, chemical and isotopic
  • 1998
  • Oxugen-isotope and C 14 data associated with Late Pleistocene syngenetic ice-wedges in mountains of Magadan region, Siberia
  • 1998
  • To explore the paleoclimatic role of the NBC, (North Brazil Current), the AA. studied a sediment core from the upper continental slope off northeastern Brazil. They used radiocarbon dating and oxygen isotope data for age control. Variations
  • in the carbonate content and the ratio between the elements Ti, Fe, and Ca were used as continental climate indicators. To reconstruct past hydrographic conditions, they measured the stable oxygen isotope ratios in the carbonate shells of 2 shallow-dwelling
  • 1998
  • Atmospheric circulation ; Carbon ; Clay mineral ; Holocene ; Isotope analysis ; Lacustrine sediment ; Monsoon ; Oxygen 18 ; Palaeogeography ; Palaeolake ; Palynology ; Saudi Arabia ; Yemen
  • Paleoecology and paleohydrology of the Ramlat as-Sab'atayn are reconstructed from a comparative study including sedimentology, mineralogy, stable isotope ratios of carbonates, and palynology of lacustrine sediments recovered from the al-Hawa
  • 1998
  • Le Pléistocène et les colonnes d'isotope d'oxygène des dépôts du fond
  • Dating ; Geochronology ; Glaciation ; Isotope analysis ; Marine sediment ; Pleistocene ; Quaternary ; Sea floor ; Stratigraphy
  • 1998
  • Atlantic Ocean ; Baltic Sea ; Biogeochemistry ; Continental shelf ; Dating ; Eutrophication ; Geochemistry ; Isotope analysis ; Marine sediment ; Pollution ; Sedimentation
  • 1998
  • This paper reports the chronology as established by the uranium-series dating on a core drilled from Badwater Basin in Death Valley. To assess the source of uranium in these lacustrine deposits, the AA. have also analyzed uranium and its isotopic
  • 1998
  • England ; Floodplain ; Geochemistry ; Grain size distribution ; Isotope analysis ; Microrelief ; Sediment transport ; Sedimentation ; Spatial variation ; Stream ; United Kingdom
  • 1998