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  • Accuracy of North American human skeleton ages
  • This study examines the dichotomy that C 14 ages for noncollagenous fossils are underestimated, whereas ages for collagenous fossil bones are more accurate. There is a high probability that amino acids from poorly preserved fossils will date younger
  • than the true age of the fossil and that the radiocarbon dates could be decreased by 2 000 to 9 000 yr or more. By existing AMS techniques, the measured ages would probably be Holocene, not Pleistocene.
  • 1990
  • Fission-track ages of tuff layers related to the Pliocene-Pleistocene boundary on the Boso Peninsula, Japan
  • Four additional fission-track ages (one from the Kurotaki Formation and three from the Amatsu Formation) are presented here. These fission-track ages provide restriction for the controversy on magneto-biostratigraphy.
  • 1990
  • Age and paleoclimatic significance of the Stansbury shoreline of Lake Bonneville, northeastern Great Basin
  • The AA. present new data on the geomorphology, stratigraphic position, and age of the Stansbury shoreline. In addition, they offer a paleoclimatic hypothesis to explain the Stansbury oscillation.
  • 1990
  • Relative ages of wetland and upland surfaces as indicated by pedogenic development
  • This paper investigates the relationship between the relative age of Coastal Plain surfaces, as indicated by the degree of soil profile development and wetness characteristics. The goal is to determine the extent to which wetlands can be considered
  • 1990
  • Younger Dryas climatic reversal in Northeastern USA? AMS ages for an old problem
  • 1990
  • Factors that interfere with the age determination of rock varnish
  • 1990
  • U-Pb zircon ages of volcanism and plutonism in the Mishibishu greenstone belt near Wawa, Ontario
  • 1990
  • Ages of travertine deposits in eastern Grand Canyon National Park, Arizona
  • 1990
  • Reciet periglacial structures. Occurrences, age and development in different matrices on a coastal plain of southwestern Sweden
  • 1990
  • The purpose of this paper is to access the effect of climate on peat accumulation in Canada. Four aspects of the subject are considered : how geographic and historic gradients of temperature and precipitation compare with the distribution and age
  • 1990
  • The objective of this paper is to present evidence for a different age for the lava and the associated soils, based on the amount of pedogenic carbonate in the soil that buries the lava, on dated volcanic ash that occurs upstream along the valley
  • 1990
  • The purpose of this article is to examine cosmogenic production of 3He in a basalt flow with a very well-constrained age, to use that production rate to date other geologic events such as flood events and volcanic eruptions, and to discuss problems
  • 1990
  • In this paper, the AA. consider how age variations, as reported, may allow alternative interpretations of existing glacial-stratigraphic models.
  • 1990
  • in Michigan and Wisconsin, to arrive at estimates of the geochronometric ages of treethrow mounds.
  • 1990
  • The results of this study suggest that detailed analyses of episodic alluvial and aeolian loess deposits and paleosols may yield important information on age of paleosols and paleoclimates that persisted during the time of their development.
  • 1990
  • that what appeared to be an ecological mixing was probably a taphonomic problem, wherein full-glacial-age fossils were probably reworked into latest Wisconsin sediments.
  • 1990
  • ) sediment dating. Seventeen TL dates were measured. None of the TL dates contradict the ages given by radiocarbon. Older dune deposits have also been dated to address the wider problem of the episodic nature of dune emplacement.
  • 1990
  • Article historique sur les diverses conceptions et représentations du cycle de l'eau. Deux époques apparaissent : l'époque du pragmatisme et des spéculations du premier millénaire avant J.-C. à la fin du Moyen Age| la période d'observations, mesures
  • 1990
  • Analysis of observational and proxy forms of evidence of climatic change especially in the Alps and the Rocky Mountains for three time scales : late glacial maximum (ca 18 000 B.P.)| little ice age (ca A. D. 1550-1850)| and recent, the last based
  • 1990
  • Action anthropique ; Agriculture ; Agropédologie ; Analyse pollinique ; Géographie historique ; Géographie physique ; Micromorphologie ; Moyen Age ; Palynologie ; Paléo-environnement ; Pays-Bas ; Plaggen ; Pédogenèse ; Siècle 20 ; Sol ; Sol sableux
  • 1990