inscription
PORTAIL D'INFORMATION GÉOGRAPHIQUE

Résultats de la recherche (178 résultats)

Affinez votre recherche

Par Collection Par Auteur Par Date Par Sujet Par Titre
  • Eau souterraine ; France ; Géochimie ; Géographie physique ; Hydrochimie ; Hydrogéologie ; Isotope ; Karst ; Provence-Alpes-Côte d'Azur ; Traçage ; Vaucluse
  • Etude par traçage naturel (géochimique et isotopique) des eaux de la région, démontrant que la Fontaine de Vaucluse n'est pas le seul exutoire des Plateaux de Vaucluse. - (AW)
  • Cycle de l'eau ; Géographie physique ; Hydrologie ; Isotope ; Recherche ; Technique de recherche
  • Applications hydrologiques des techniques isotopiques : instrumentation, traçage et surtout comportement des isotopes du milieu naturel en tant que révélateur du fonctionnement du cycle hydrologique. - (CG)
  • Les isotopes du milieu dans les eaux naturelles
  • Eau ; Ecoulement ; Géographie physique ; Hydrogéologie ; Hydrologie ; Hydrologie continentale ; Isotope ; Nappe aquifère ; Recharge ; Technique de recherche
  • Les isotopes du milieu (isotopes constitutifs de l'eau, isotopes dissous) peuvent être utilisés à des fins scientifiques et techniques en hydrologie: étude des crues, du rôle des neiges, du transfert de l'eau et des modalités de recharge dans la
  • Oxygen isotope constraints on surface ocean temperatures
  • Donnée substitutive ; Foraminifère ; Géographie physique ; Isotopes de l'oxygène ; Paléoclimatologie ; Quaternaire zone chaude ; Température de surface de l'océan
  • Published oxygen isotope results from benthic and planktonic foraminifera are used to constrain the extent to which surface ocean temperatures in the tropics changed between glacial and inter-glacial time. The possible impacts of bioturbation
  • and of the redistribution of oxygen isotopic ratios within the sea, putting aside the oxygen isotope results, are consistent with the CLIMAP project conclusion that tropical ocean temperatures remained within ca. 2oC of their present value.
  • On the isotopic composition of late Cenozoic sea water
  • Cénozoïque ; Eau de mer ; Facteur glaciologique ; Géographie physique ; Inlandsis ; Isotope ; Océan ; Paléo-océanographie ; Paléoclimatologie ; Paléotempérature ; Quaternaire marin
  • Up to one fourth of the isotopic change in foraminifera found in deep-sea cores (or some 0.3 /) may be due to a gradual change in the isotopic composition of the Antarctic and Greenland ice sheets. Therefore the peak-to-valley variation of the 0
  • uncorrected isotopic curves, and the last stadial (e.g. Weichselian around 18,000 B.P.) less intense.
  • Oxygen isotope studies and quaternary marine climates in Climatic variations and variability: facts and theories.
  • This paper describes the isotopic fractionations and shows that variations of the oxygen isotopic composition of foraminifera along deep sea cores are generally a continental ice volume index and thus a worldwide oceanic stratigraphic marker
  • . Specific applications of oxygen isotopes related either to past temperature changes or local sea water isotopic composition variations are presented.
  • Oxygen isotope ratios from tree rings containing compression wood
  • During studies of oxygen isotope : temperature relationships for tree rings in the Canadian Rockies, the AA. noted differences in oxygen isotope ratios between samples from compression wood and normal radii in the same stem. This paper briefly
  • Migracija radioaktivnyh izotopov v vodnyh ekosistemah (Migration des isotopes radioactifs dans les écosystèmes aquatiques)
  • Eau ; Ecosystème ; Géographie physique ; Hydrobiologie ; Isotope ; Modèle
  • Middle Pliocene climatic change in the western Mediterranean from faunal and oxygen isotopic trends
  • Ere tertiaire ; Géographie physique ; Isotope O18-O16 ; Méditerranée ; Méditerranée, Ouest ; Paléoclimatologie ; Paléontologie ; Pliocène
  • Faunal and oxygen isotopic evidence for surface water salinity changes during sapropel formation in the eastern Mediterranean
  • Datation ; Eau de surface ; Foraminifère ; Géochronologie ; Géographie physique ; Isotope ; Milieu marin ; Méditerranée ; Oxygène ; Paléoclimatologie ; Salinité
  • A review of various factors influencing the stable carbon isotope ratio of organic lake sediments by the change from glacial to post-glacial environmental conditions
  • Composition isotopique ; Géochimie ; Géographie physique ; Holocène ; Isotopes du carbone ; Lac ; Paléolimnologie ; Quaternaire ; Quaternaire supérieur ; Sédiment lacustre ; Sédimentologie
  • Stable-isotope geohydrology of the Lower Maner Basin, Andhra Pradesh, India
  • Andhra Pradesh ; Cours d'eau ; Eau ; Eau souterraine ; Géochimie ; Géographie physique ; Hydrochimie ; Inde ; Isotope ; Précipitation
  • Structure and timing of the last deglaciation : oxygen-isotope evidence
  • Foraminiferal oxygen-isotope data from 24 Tropical Atlantic sediment cores, constrained by 77 14 C dates, are stacked to form a composite record of isotopic Termination 1. This record indicates that most of the isotopic transition at the end
  • An isotopic study of paleosol carbonates from Olduvai gorge
  • The isotopic composition (oxygen and carbon isotopes) of paleosol carbonates is used to give estimates of the paleoclimatic history of East Africa during the Plio-Pleistocene. Three major periods of climatic change in this terrestrial setting
  • occurred at about 1.67, 1.3 and 0.6 myr. These involved major changes in flora as well as major changes in the isotopic composition of meteoric water. Overall, the climate has become warmer and more arid over the part 2.2 myr.
  • Carbon isotopic changes in benthic foraminifera from the western South Atlantic: reconstruction of glacial abyssal circulation patterns
  • Analyse isotopique ; Atlantique ; Atlantique Sud ; Circulation abyssale ; Foraminifère benthique ; Géographie physique ; Isotope O18-O16 ; Isotopes du carbone ; Océan ; Paléohydrologie ; Pléistocène supérieur ; Quaternaire marin ; Rio Grande ; Vema
  • Oxygen-and carbon-isotopic analyses have been performed on the benthic foraminifer Planulina wuellerstorfi in seven Late Quaternary cores from the Vema ChannelRio Grande Rise region.
  • Oxygen-isotope analyses and Pleistocene ice volumes
  • The oxygen-isotope record from fossil foraminifera in deep-sea sediments is commonly used as a proxy for global ice volume. The linkage between O and ice volume, however, is probably nonlinear. The AA. have developed a simple numerical model
  • of the isotopic response of the oceans to ice-volume change. They illustrate the response of their model to simple hypothetical ice-volume transitions of ice growth and ice decay. Sensitivity tests are illustrated for all model parameters. The results suggest
  • that oxygen-isotope records reproduce the general patterns on ice-volume change fairly accurately. The foraminiferal isotope record, however, may misrepresent the true amplitude of the ice-volume signal and lag true ice volume by 1000 to 3000 yr.
  • Strontium isotopes in trees as an indicator for calcium availability
  • Preliminary analyses of water (precipitation, throughfall, runoff, soil-water), soil (mineral matter) and biological material (trees, musselshells) show that the use of the strontium isotope ratio 87 Sr/86Sr is a powerful tool in estimating
  • Deutérium ; Eau ; Géographie physique ; Hydrochimie ; Hydrométrie ; Isotope ; Oxygène 18
  • This note recommends to hydrologists and hydrogeologists a new method of presentation of natural isotopic contents of waters. That may contribute to easier interpretation of such measurements. It is illustrated with two examples of recent isotopic
  • Monsoon fluctuations in two 20,000-yr B.P. Oxygen-isotope/pollen records off southwest India
  • Carotte océanique ; Géographie physique ; Holocène ; Inde ; Isotopes de l'oxygène ; Mousson ; Palynologie ; Paléoclimatologie ; Pléistocène supérieur ; Quaternaire zone chaude ; Variation climatique
  • Information about the origin of thermomineral waters and gas by means of environmental isotopes in eastern Azerbaijan, Iran, and southeast France in Hydrogeothermal studies. 26th International geological congress.
  • Azarbaïjan ; Deutérium-Oxygène 18 ; Eau météorique ; Eau souterraine ; Eau thermominérale ; France ; France du Sud-Est ; Géographie physique ; Hydrogéologie ; Hydrothermal ; Iran ; Isotope ; Recharge naturelle ; Source ; Tritium ; Volcanisme