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971.
Water Resources - Linearized equations of two-dimensional hydraulics have been analyzed by the method of small perturbations within a wide range of alluvial features sizes at large values of Froude... 相似文献
972.
973.
H.V. Warren S.J. Horsky A. Kruckeberg G.H.N. Towers J.E. Armstrong 《Journal of Geochemical Exploration》1983,18(3):169-173
Summary of biogeochemical prospecting for mercury mineralization in the Pinchi Fault is given. One thousand two hundred and eight plant samples were collected and analyzed for mercury. In mineralized areas the typical mercury content of dried plants was not less than 0.2 and 0.4 μg/g and even concentrations between 0.6 and 1.6 μg/g were observed. In nonmineralized zones at least 90% of the plants contained no more than 0.15 μg/g of mercury. Analytical and sampling procedures are described. 相似文献
974.
Studies on saprolitized charnockites associated with a landslip observed in the Blue Mountains in close proximity of the Porthimund Dam (11°22'E 76°34′30″N), Nilgiris District, Tamilnadu State, South India, are reported.Laboratory investigations of the geotechnical properties were carried out to evaluate the nature and degree of weathering quantitatively for estimating the soundness of the charnockites constituting the slip zone. The results of per cent decomposed product of the crest, scarp and toe portions of the slip denote positive correlations with porosity and compressibility; and negative correlations against density, wave velocity, Young's modulus, compressive strength and tensile strength. It is also seen that in the absence of the information on decomposed product, weatherability could still be evaluated considering the per cent change of any physical parameter.Such studies should prove valuable in the mapping of weatherability zones and the assessment and determination of foundation conditions. 相似文献
975.
Astronomy Reports - A large fraction of the energy released during the gravitational collapse of the core of a massive star is carried by neutrinos. Neutrinos play the main role in explaining... 相似文献
976.
Geotectonics - Synthesis of the results of U–Pb dating of detrital zircons (dZr) from the Uppermost Precambrian–Phanerozoic strata of the southern and southeastern framing of the East... 相似文献
977.
R. R. Gabdullin N. V. Badulina E. A. Bakai E. V. Rubtsova A. Yu. Yurchenko E. V. Karpova A. V. Ivanov M. A. Varzanova A. V. Sergienko T. A. Konovalova M. V. Parakhina 《Moscow University Geology Bulletin》2018,73(4):346-360
The composition and origin of the Callovian–Oxfordian deposits of the Sudak Bay were characterized on the basis of the generalization and analysis of our own results, as well as published and unpublished data. The botanical future was first implemented for the geological mapping of the Oxfordian deposits. 相似文献
978.
979.
Wet granular materials are three-dimensionally simulated by the discrete element method with water bridges incorporated between particles. The water bridges are simplified as toroidal shapes, and the matric suction is constantly maintained in the material. A comparison with experimental tests in the literature indicates that the toroidal shape approximation may be one of the best choices with high practicability and decent accuracy. Mechanical behaviours of wet granular materials are studied by triaxial tests. Effects of particle size distributions and void ratios are investigated systematically in this study. The hydraulic limit of the pendular state is also discussed. It gives the capillary cohesion function which is not only determined by the degree of saturation but also positively correlated to relative density and particle size polydispersity and inversely proportional to mean particle size. Furthermore, the capillary strengthening effect is also analysed microscopically in aid of the Stress–Force–Fabric relationship, mainly in fabric anisotropy, coordination number and stress transmission pattern, which revealed the micro-mechanisms of the additional effective stress induced by capillary effect. 相似文献
980.
V. I. Grebenshchikova M. I. Kuzmin O. A. Proydakova O. V. Zarubina 《Doklady Earth Sciences》2018,480(2):735-740
The long-term data (1950–2017) on the chemical composition of the water from the source of the Angara River, which is the only run-off from Lake Baikal, a large and clean fresh water reservoir, are presented. The absence of water contamination despite the anthropogenic influence is shown. The similarity and constancy of the current composition of the waters in the lake and the Angara River are recorded. It is recommended to continue geochemical studies of this unique world heritage site. 相似文献