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Geomorphological applications of cosmogenic isotope analysis

Geomorphological applications of cosmogenic isotope analysis
Bibliography ; Dating ; Erosion rate ; Geochemistry ; Geomorphology ; Isotope analysis ; Mass movement ; Weathering
The AA. focus on the geomorphological applications of in situ-produced cosmogenic isotope analysis. The past decade has seen a rapid growth in applications of cosmogenic isotope analysis to a wide range of geomorphological problems
, and the technique is now playing a major role in dating and quantifying rates of landscape changes over timescales of thousands to several millions of years.

New isotopic and sedimentological measurements of the Thabaseek deposits (South Africa) and the dating of the Taung hominid

New isotopic and sedimentological measurements of the Thabaseek deposits (South Africa) and the dating of the Taung hominid
Archeological site ; Cape Province ; Dating ; Geochemistry ; Isotope dating ; Quaternary ; Sedimentology ; South Africa ; Stratigraphy

Carbon isotope composition of lake sediments in relation to lake productivity and radiocarbon dating

Carbon isotope composition of lake sediments in relation to lake productivity and radiocarbon dating
C14 dating ; Canada ; Carbon ; Geochemistry ; Isotope ; Lacustrine sediment ; Ontario ; Paleo-ecology ; Paleo-environment ; Quaternary
Canada ; Carbone ; Datation C 14 ; Géochimie ; Isotope ; Ontario ; Paléo-environnement ; Paléo-écologie ; Quaternaire ; Sédiment lacustre
The purpose of this paper is to contribute to developing criteria for evaluating the validity of radiocarbon dates of lake sediments from basins in calcareous terrain. In particular, the AA. test the hypothesis that the 13C content of lake sediments

Dating methods : geochronology and landscape evolution

Dating methods : geochronology and landscape evolution
Absolute dating ; Dating ; Geochronology ; Geomorphology ; Isotope dating ; Methodology
Revue des publications récentes sur le développement des isotopes utilisables pour dater des périodes de cent mille à dix millions d'années et sur les techniques de datation absolue disponibles pour quantifier des processus géomorphologiques au

Accuracy of post-bomb 137Cs and 14C in dating fluvial deposits

Accuracy of post-bomb 137Cs and 14C in dating fluvial deposits
Alluvium ; Arid land;Arid environment ; Arizona ; C14 dating ; Dating ; Flood ; Fluvial processes ; Isotope ; Semi-arid area ; United States
Alluvion ; Arizona ; Crue ; Datation ; Datation C 14 ; Domaine aride ; Domaine semi-aride ; Etats-Unis ; Fluviatile ; Isotope
The AA. evaluate the accuracy and precision of 137Cs and 14C in dating post-1950 deposits from known floods on two rivers in Arizona.

Dating methods: review for 1994

Dating methods: review for 1994
Aminostratigraphy ; C 14 dating ; Dating ; Geomorphology ; Isotope dating ; Methodology ; Palaeogeography ; Palaeomagnetism ; Thermoluminescence

Dating methods

Dating methods
Aminostratigraphy ; Bibliography ; C 14 dating ; Dating ; Isotope analysis ; Methodology ; Palaeomagnetism ; Thermoluminescence

Chronology and paleohydrology of Late Quaternary high lake levels in the Manyara Basin (Tanzania) from isotopic data (18O, 13C, 14C, Th/U) on fossil stromatolites

Chronology and paleohydrology of Late Quaternary high lake levels in the Manyara Basin (Tanzania) from isotopic data (18O, 13C, 14C, Th/U) on fossil stromatolites
Dating ; Isotope ; Lake level ; Palaeogeography ; Palaeohydrology ; Quaternary ; Tanzania
Datation ; Isotope ; Niveau lacustre ; Paléogéographie ; Paléohydrologie ; Quaternaire ; Tanzanie
In this article, new isotopic data on the hydrology and paleohydrology of the Lake Manyara basin are presented. They complement previous studies on lakes Natron and Magadi, to the north, and provide additional information on late Pleistocene

Structure and timing of the last deglaciation : oxygen-isotope evidence

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

Dating methods: a review for 1995

Dating methods: a review for 1995
Absolute dating ; Aminostratigraphy ; Bibliography ; C 14 dating ; Dating ; Glacial features ; Isotope dating ; Palaeo-environment ; Palaeomagnetism ; Palaeosol ; Quaternary ; Thermoluminescence

U-series dating by the TIMS technique of land snails from paleosols in the Canary Islands

U-series dating by the TIMS technique of land snails from paleosols in the Canary Islands
Canary Islands ; Dating ; Fauna ; Isotope dating ; Methodology ; Palaeo-ecology ; Palaeosol ; Uranium
A sequence of seven superimposed paleosols developed on eolian calcarenites and alluvium was sampled on the island of Lanzarote in order to examine the possibility of dating land snail shells by the U-series method, using a TIMS technique allowing
measurement of U and Th isotopes in very small samples.

Cosmogenic 3He ages and frequency of late Holocene debris flows from Prospect Canyon, Grand Canyon, USA

Cosmogenic isotopes in geomorphology
Arizona ; C 14 dating ; Canyon ; Dating ; Fluvial dynamics ; Isotope dating ; Mudflow ; United States of America ; Watershed
In this study, the AA. report 3He dates for the oldest surfaces on debris flows in Prospect Canyon and use them with conventional 14C dates and photographic evidence to estimate the frequency of the late Holocene debris flows that have affected Lava

Grundwasser - Altersbestimmung : Methodik und Anwendung (Groundwater - dating : methods and applications)

Grundwasser - Altersbestimmung : Methodik und Anwendung (Groundwater - dating : methods and applications)
The paper gives a short survey of the most important methods of groundwater dating on the basis of isotope measurements. The fundamental models (piston flow model, exponential model...) are discussed. Practically important possibilities

Continental oxygen isotopic record of the last 170,000 years in Jerusalem

Continental oxygen isotopic record of the last 170,000 years in Jerusalem
Cave ; Climatic variation ; Interglacial ; Isotope dating ; Israel ; Jerusalem ; Karst ; Oxygen 18 ; Palaeoclimate ; Quaternary ; Th/U dating
A long radiometrically dated oxygen isotopic record of continental climatic variations since the penultimate glaciation was obtained from a stalagmite deposited in a sealed cave in Jerusalem. This record shows that speleothems have the potential
of assigning dates to long- and short-term climatic events, with possible refining of Milankovitch tuning of ice and marine records which themselves are not datable. Short-term (1000-yr) events are very significant in the region, reaching 50% of glacial

Phytolith and carbon isotope evidence for late Quaternary vegetation and climate change in the Southern Black Hills, South Dakota

Phytolith and carbon isotope evidence for late Quaternary vegetation and climate change in the Southern Black Hills, South Dakota
C 14 dating ; Carbon ; Climatic variation ; Grassland ; Holocene ; Isotope analysis ; Palaeobiogeography ; Quaternary ; South Dakota ; United States of America ; Vegetation
Analyses of phytoliths and carbon isotopes document the rate and nature change in late Quaternary grasslands in the Red Valley of the southern Black Hills. This paper will evaluate the temporal sensitivity and spatial limits of the methods.

Palaeoclimate signals as inferred from stable-isotope composition of ground ice in the Verkhoyansk Foreland, Central Yakutia

Palaeoclimate signals as inferred from stable-isotope composition of ground ice in the Verkhoyansk Foreland, Central Yakutia
Asian part of Russia ; C 14 dating ; Deuterium ; Ice wedge ; Isotope analysis ; Oxygen 18 ; Palaeoclimate ; Periglacial features ; Permafrost ; Quaternary ; Sakha ; Siberia
In this study, the AA. present stable-isotope data from ice-wedges of Weichselian and Holocene ages from the foreland of the Verkhoyansk Mountains, as well as from Central Yakutia, and discuss their palaeoclimatic implications.

Stable isotope stratigraphy of a late last interglacial speleothem from Rana, northern Norway

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

Stable carbon isotope record of Holocene environmental change in the central Great Plains

Stable carbon isotope record of Holocene environmental change in the central Great Plains
C 14 dating ; Climatic variation ; Drought ; Holocene ; Isotope analysis ; Loess ; Nebraska ; Organic materials ; Palaeo-environment ; United States of America
First the AA. review the background and methodology behind the use of stable isotopes of carbon in paleoenvironmental research; then, they consult the literature to describe their knowledge of ecosystem and climate change, including recurring

Dating of Greenland ice cores by flow models, isotopes, volcanic debris, and continental dust

Dating of Greenland ice cores by flow models, isotopes, volcanic debris, and continental dust
Datation ; Glace ; Groenland ; Géochronologie ; Géographie des régions polaires ; Isotope ; Stratigraphie ; Variabilité
notre ère), à partir des retombées de cendre volcanique soluble. Les variations saisonnières en micro-particules ou en isotopes stables sont mesurées pour trois carottes de 400m de longueur, venant du Groenland. Description des techniques utilisées pour
rétablir la forme des profils d'isotopes lourds. Evaluation de l'erreur absolue de datation.

Reevaluation of the lake-sediment chronology in the Dead Sea Basin, Israel, based on new 230Th/U dates

Reevaluation of the lake-sediment chronology in the Dead Sea Basin, Israel, based on new 230Th/U dates
Dating ; Dead Sea ; Geochronology ; Isotope analysis ; Israel ; Lacustrine sediment ; Lake level ; Palaeogeography ; Stratigraphy ; Th/U dating
. The general validity of the ages was demonstrated by subjecting them to tests of internal isotopic consistency, agreement with stratigraphic order, and concordance with 14C ages.

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