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941.
942.
Donald W. Forsyth 《Geophysical Journal International》1975,43(1):103-162
943.
A Physical Model for the Creation of the Lithosphere 总被引:1,自引:0,他引:1
Douglas W. Oldenburg 《Geophysical Journal International》1975,43(2):425-451
944.
D. R. Van Stempvoort T. W. D. Edwards M. S. Evans W. M. Last 《Journal of Paleolimnology》1993,8(2):135-147
This pilot study examines the potential of obtaining a sedimentary record of paleoenvironmental/climatic/hydrologic conditions for saline Redberry Lake in southern Saskatchewan, Canada. The tools are mineralogy, stable isotopes and pigments. The upper meter of an offshore sediment core contains 10 to 20% by weight aragonite (CaCO3), which apparently precipitated in the water column. The 18O and 13C of the bulk aragonite (corrected for content of detrital calcite) vary by 4 to 5. Enrichment in 18O in aragonite is significantly correlated with pigment concentrations (chlorophyll a, phaeophytin). The 18O and pigment data provide evidence for relatively dry and/or warm conditions and high limnetic productivity for the period 2500 to 1500 yrs B.P. After 1500 B.P., the climate was apparently similar to the present, with two episodes of relatively enhanced productivity, dryness and/or warmth, at around 1000 to 900 and 500 to 200 B.P. During the past century, Redberry Lake has decreased approximately 8 m in depth and its salinity has doubled. No clear sedimentary signal was observed in response to these recent hydrologic trends. These changes have not been associated with a significant climate trend in the region, but may have been induced by land use changes in the catchment.This publication is the third of a series of papers presented at the Conference on Sedimentary and Paleolimnological Records of Saline Lakes. This Conference was held August 13–16, 1991 at the University of Saskatchewan, Saskatoon, Canada. Dr. Evans is serving as Guest Editor for this series. 相似文献
945.
Large-scale deformation associated with ridge subduction 总被引:1,自引:0,他引:1
Eric L. Geist Michael A. Fisher David W. Scholl 《Geophysical Journal International》1993,115(2):344-366
946.
Remnants of the Last Interglacial shoreline occur at Middle Lagoon on the far south coast of New South Wales. Relict beach sediments can be traced to a height of at least +4.8 m and are indicative of a former mean sea level of about +3 m. Thermoluminescence (TL) ages of 126 ± 13 ka and 114 ± 15 ka were determined for beach and aeolian facies respectively. Sands in the lower part of an exposure on the adjacent Gillards Beach gave TL ages of 108 ± 13 ka, but sands in the upper part of that exposure gave an age of 19.9 ± 3.5 ka. This chronological evidence of a stratigraphic unconformity in what was initially taken as pedogenic differentiation at Gillards Beach is supported by contrasting electron traps and colour centres in crystal lattices of quartz grains in these two samples. No tectonic displacement is apparent. This site provides the first evidence of the Last Interglacial sea level for 1000 km along the coast between Gippsland and Newcastle. 相似文献
947.
948.
949.
Plane Waves in Linear Viscoelastic Media 总被引:5,自引:0,他引:5
Peter W. Buchen 《Geophysical Journal International》1971,23(5):531-542
950.