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  • ALLEN, D. C.
  • SIMPSON, C. J. S. M.
  • Declining trend in the C 13/C 12 ratio of atmospheric carbon dioxide from tree rings of South African Widdringtonia cedarbergensis
  • This paper reports the first high-resolution (annual) C 13/C 12 chronology for both Africa and the Southern Hemisphere. The 77-yr stable carbon isotope chronology was developed from 6 Widdringtonia cedarbergensis trees from a site in the Cedarberg
  • Mountains, Western Cape Province, South Africa. The results indicate that C 13/C 12 ratios are not different from 1900 to 1949. After 1949, however, values become significantly more negative to 1977. This decline can be related to the anthropogenic impact
  • Potential for C 14 dating of biogenic carbonate in Hackberry (Celtis) endocarps
  • Action biogène ; Archéologie ; Carbonate ; Datation ; Datation C 14 ; Etats-Unis ; Méthodologie ; Nebraska ; Quaternaire ; Utah
  • Archaeology ; Biogenic process ; C 14 dating ; Carbonate ; Dating ; Methodology ; Nebraska ; Quaternary ; United States of America ; Utah
  • This paper reports on C 14 systematics of modern hackberry endocarp carbonate and examine its potential as a C 14 dating substrate. C 14 dates of fossil endocarp carbonates compared favorably with dates obtained by other means at archaeological
  • and geological sites ranging in age from the late Pleistocene through the early Holocene. They therefore suggest that hackberry endocarp is a suitable substrate for C 14 dating provided that its morphological and mineralogical integrity is preserved.
  • A magnetostratigraphic comparison between 14 C years and varve years during the Late Weichselian indicating significant differences between the time-scales
  • Datation ; Datation C 14 ; Géographie de l'Europe ; Paléomagnétisme ; Stratigraphie ; Suède ; Technique de recherche ; Varve
  • Statistical correlations between the two independantly dated time-scales suggest that at 10 500-10 200 14 C years B. P. the varvechronology exceeds the 14 C chronology by the order of 500-600 varve/year. Further correlations between the time-scales
  • at 12 000 14 C years B. P. suggest that the difference between the chronologies increased steadily from 12 000 to 10 000 14 C years B. P. If these correlations are correct they imply that the 14 C production rate increased steadily during the Late
  • Commentary on G. C. Pickvance's The rise and fall of urban movements...
  • DEVEAUX, C.
  • BLANCHON, C.
  • DEVEAUX, C.
  • BLANCHON, C.
  • Réédition de l'ouvrage de 1966 revu par C. G. Topley.
  • TOPLEY, C. G., (Collaborateur)
  • Yields of agriculture in the E. C. regions 1950-1973.
  • Les paysages de l'Antiquité. Terres et cadastres de l'Occident romain, IVe siècle avant J.-C./IIIe siècle après J.-C.
  • COLLIN-DELAVAUD C.
  • KING, C. A. M., (Editeur scientifique)
  • JOHNSON, B. L. C.
  • L eau dans les espaces funeraires d Alexandrie aux epoques grecque et romaine (IVeme siecle av. J-C - IIIeme siecle ap. J-C)
  • Representations et celebrations du pouvoir imperial dans les provinces syriennes d Auguste a Constantin : (31 av J-C - 337 ap J-C)
  • C. Colomb et la Riviera ligure
  • Amérique ; COLOMB (C.) ; Découverte ; Exploration ; Histoire de la géographie
  • PAMPALONI, C.