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991.
Uranium has been measured by homogenized fission track analysis in 34 samples of 22 achondrites. Potassium has been determined in aliquots of eleven of these. The results, combined with previous Al data, are not compatible with achondrite formation from chondritic material by previously suggested fractional melting or metal-sulfide segregation processes. 相似文献
992.
Attia A. Ashour 《Physics of the Earth and Planetary Interiors》1973,7(3):303-312
The different methods and techniques employed in the theory of electromagnetic induction in thin sheets are reviewed and the methods for approximation to the solution are indicated. These depend on whether the sheet is closed or finite and on whether the integrated conductivity and/or the frequency of variations is high or low.Results for induction in finite sheets which are suitable for ocean modelling are given. These include sheets of perfect conductivity and sheets of finite conductivity which is either discontinuous or continuous at the boundary. The dependence of the “coastline effect” for a global ocean on the location of the edge of the continental shelf, the period of variation of the external field and the conductivity of the underlying earth is explained. 相似文献
993.
P. A. Mohr 《Bulletin of Volcanology》1962,24(1):421-428
Recent Quaternary faulting and vulcanicity accompanied by peculiar subsidence phenomena in the northern part of the Main Ethiopian Rift are described for the first time. A suggested sequence of geological events is given. 相似文献
994.
F. Zebender P. Zimmermann R. Märki A. Hörler H. Ambübl 《Aquatic Sciences - Research Across Boundaries》1961,23(1):296-308
Ohne Zusammenfassung 相似文献
995.
Summary Relatively good correlation between such remote phenomena as microseisms, geomagnetic activity and ionospheric absorption of radio waves has been observed. These phenomena are probably connected by a considerably increased penetration of energetic particles into the atmosphere under conditions of geomagnetic activity. 相似文献
996.
S. E. HJELT 《Geophysical Prospecting》1976,24(1):1-18
By using two components of anomalous magnetic fields and a formulation including complex numbers it is possible to calculate the position parameters of thick plates and both magnetization and position of thin plates directly from any two or three points of anomaly profiles. The formulae (interpretation operators) allow automatic topographic corrections to be made. The new two-component operators give more reliable results than the conventional methods of interpretation. The variance of the parameter values obtained with subsequent points of an anomaly measures directly, the total error of interpretation. The application of infinite thin plate operators to a long profile results in characteristic patterns, from which the estimation of the number of plates and their approximate position is possible. 相似文献
997.
998.
999.
1000.
Water Resources - The forked channel is a rare and poorly known type of branching channel, the distribution of flow in which is of key importance for water transport, economic activities, and water... 相似文献