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The presence of the Brunhes-Matuyama magnetic reversal in deep-sea core sediments makes possible an alternative to the usual K/Ar radioisotope method of dating the reversal as found in rocks. The alternative method uses correlations of Northern
Hemisphere summer insolation with oxygen-isotope ratios from tropical cores. The latitude-dependent insolation variations are calculated from planetary mechanics and thus provide a highly accurate astronomical time scale. The insolation variations strongly
influence glacial-ice volume fluctuations that dominate the oxygenisotope ratio changes recorded in core sediments. The summer half-year insolation variations are identified with corresponding isotope-ratio changes in cores from the present through glacial
isotope-ratio minima in the two cores (relative to ages based on uniform overall deposition) to match the ages of low-eccentricity insolation minima. The age shifts reflect residual nonuniformities of deposition. The validity of this matching procedure
1982

Comparisons of sedimentation rates obtained by Pb and pollen analyses of 1-m cores collected throughout the Potomac Estuary show good agreement in the majority of cores that can be analyzed by both methods. Most of the discrepancy between
the methods can be explained by the analytical precision of the Pb method and by the exactness with which time horizons can be identified and dated for the pollen method. X-radiographs of the cores and the distinctness of the pollen horizons preclude
1982

Carbonate content and faunal composition of two gravity cores from the coastal Arabian sea provide evidence of a major environmental change in surface ocean waters about 13,000 yr B.P. Radiocarbon dating indicates that deposition rates ranged from
1.8 to 9.8 cm/10 yr, with a major change in rate occurring in one core at about 7500 yr B.P.
1982

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.
1982

Two sediment cores of 4 m length from Mecklenburger Bay and the Arkona basin were analysed as to their contents of Fe, Mn, Zn, Cr, Ni, Pb, Cu, Co, Cd and Hg, their origin, and their influence. (HL).
1982

basinwide study, the climatic optimum 125,000 yr ago and the glacial maximum 18,000 yr ago. In addition, patterns of climatic change were examined in seven piston cores from 127,000 yr ago to the present day.
1982

degree by high-intensity sulfur-rich eruptions (e.g., Agung, 1963), which may however be relatively small in total ejecta volume. Such eruptions leave little geologic record, but appear as acidity peaks in polar ice cores.
1982

(1975) ; Advection froide ; Atmosphère ; Circulation atmosphérique ; Circulation méridienne ; Convection ; Corée du Sud ; Couche limite planétaire ; Courant ; Courant chaud ; Defense military Satellite Program ; Dynamique de l'atmosphère ; Effet
1982

Analysis of the benthonic foraminiferal faunas in two sediment cores recovered from the Vema and Hunter Channels in the western South Atlantic shows that the level of the transition between deep and bottom waters shallowed sharply about 700,000 yr
1982

ont affecté en janvier 1972 la façade orientale de l'Asie, où l'A. les suit de la Corée au sud des Philippines. D'importantes téléconnexions sont mises en évidence entre les systèmes tempérés et les systèmes convectifs des basses latitudes, d'échelle
1982

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