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131.
Summary The problem of the propagation of finite Love Waves in a heterogeneous elastic half space lying over a homogeneous elastic half space, using the quasilinear stress-strain relation due toS. Ferhst [4] is considered in detail. The variations of the parameter in the layer assumed to be of the form 1= 0e
z, 0e
z where is a constant andz is distance measured from the surface into the layer. 相似文献
132.
D. R. K. Rao 《Pure and Applied Geophysics》1972,98(1):146-152
Summary Results of sunspot cycle influence on solar and lunar ranges at a low latitude station, Alibag, outside the equatorial electrojet belt, show that the sunspot cycle association in solar ranges is three times that of the lunar ranges in thed- andj-seasons. This is in general agreement with the earlier results for non-polar latitude stations. The association with sunspot number of individual lunar amplitudes is greatest for lunar semidiurnal harmonic in thej-season. During this season, the sunspot cycle influence on lunar variations is more than that on solar variations, thereby indicating that the lunar current is situated at a level more favourable for sunspot cycle influence than the level of the current associated with solar variations. With the increase in solar activity a shift appears in the times of maxima of semidiurnal lunar variation towards a later lunar hour ine- andj-seasons and in the year. 相似文献
133.
S. Subba Rao 《Bulletin of Volcanology》1971,35(4):998-1011
Recent investigations on the Deccan Traps reveal many new findings of alkaline rocks more commonly occurring as minor intrusions than as lava flows. In comparison to the vast extent of the Deccan Traps, the alkaline rocks are negligible in their volume and are confined to tectonic belts in parts of Western India. The rocks exhibit no systematic variation in their petrographical and chemical characters thereby suggesting that they were not derived from a primary alkali olivine-basalt magma. The possibility of derivation of alkaline magma locally along the rift zones is proposed. Some of the alkaline rocks are shown to have been formed due to the effective role of volatiles in bringing dissociation of feldspar in certain cases, and alkali metasomatism in others. The syntexis of the pre-Deccan Trap carbonate rocks along the Narmada rift zone is also responsible for some occurrences. 相似文献
134.
B. S. R. Rao I. V. Radhakrishna Murthy C. Visweswara Rao 《Pure and Applied Geophysics》1973,110(1):2056-2065
Summary A common computer program for the interpretation of vertical magnetic anomalies of spheres and horizontal cylinders has been developed. The input consists of the observed anomalies noted against their distances measured from an arbitrary point in the profile and a code number for each model. The program is written so that the positions and magnitudes of the maximum and minimum anomalies are located and their ratios and signs are used to define the initial parameters of the model under consideration. The errors resulting from these approximate values are derived and are solved for the increments to be given to the initial values. The process is repeated until the sum of the squares of the errors is less than 0.25% of the sum of the squares of the observed anomalies. The method has been tested on various theoretical examples and the results justify the validity of the programme. 相似文献
135.
N. Jagan Mohana Rao P. Sathyamurthi T. V. Ramana Rao 《Pure and Applied Geophysics》1973,104(1):608-613
Summary The SCI values of zonal and meridional winds over Natal, Brasil are calculated. The results are compared with another southern Hemispheric Station Ascension Island and circulation patterns in the Stratosphere are discussed. Also a comparison is made of the zonal winds over Natal with those of an Equatorial Station (Thumba, India) and a station in Subtropics (Sonmiani, Arabian Sea islands).On leave from Dept. of Meteorology and Oceanography, Andhra University, Waltair (India). 相似文献
136.
Summary Laboratory induced polarization (IP) or overvoltage measurements over a spherical body at different depths is discussed. Some nomograms are also designed to calculate rapidly induced polarization parameters such as frequency effect, polarization factor and chargeability in the field or laboratory. 相似文献
137.
The paper presents the results of a photometric study of the hydroxyl bands (7–2) and (8–3) in the night airglow spectrum at Mt. Abu in the winter and spring of 1966–1972. The observed nocturnal variation differs from the variation expected from the theoretical studies of Hesstvedt, Hunt, Shimazaki and others. Instead of a gradual fall in intensity after sunset to shortly before sunrise, a peak in intensity is found at a time which changes from month to month and roughly coincides with the transit times of the X-ray star TAU (XR-1)-Crab Nebula. Anexplanation of the observed phenomenon is offered in terms of the increased energy output into the D and E regions of the atmospheres, increased eddy diffusion, and production, of additional O(3P) and O3 in the region 80–95 km. O3 reacting with H gives rise to OH*. 相似文献
138.
Manoranjan Rao Lalmani V.V. Somayajulu B.A.P. Tantry 《Planetary and Space Science》1973,21(6):1076-1079
Quite often the VLF hiss powers recorded by space probes are some orders of magnitude greater than those predicted by the theory of incoherent Cerenkov radiation. In this note we suggest that the wavegrowth via the Landau instability might satisfactorily account for the disparity between the theory and experiment. 相似文献
139.
Summary. Palaeomagnetic investigations were carried out on nine lava flows around the Dhar region, which constitute the northern part of the Deccan traps. The stability of remanent magnetism of these specimens was analysed by an alternating magnetic field, thermal demagnetization and memory tests. Six flows exhibited characteristic components of magnetization, with a mean direction of D =143°, I =+46° ( K = 107.1, α95 =5.5°). This gives a VGP located at 29° N, 67° W (δp =4.5°, δm = 7.0°). The lower site with normal magnetization and the upper five sites with reverse magnetization indicate a geomagnetic field reversal during the initial phases of Deccan volcanism in the Early Tertiary period. A rapid northward migration of about 18° in latitude and a simultaneous anticlockwise rotation of 37° is calculated for the subcontinent. 相似文献
140.
U. R. Rao K. G. McCracken F. R. Allum R. A. R. Palmeira W. C. Bartley I. Palmer 《Solar physics》1971,19(1):209-233
Comparison of Explorer 34 observations on solar protons in the energy range 0.7–55 MeV with similar observations from other spacecrafts show that the large field aligned anisotropies which are observed during the rise time of a flare event change to an equilibrium anisotropy coming radially from the sunward direction due to the convective removal of the solar particles. At very late times during the decay (T 4 days) the anisotropy is observed to be from a direction 45° E of the satellite-Sun line which is interpreted as indicative of positive density gradient of solar cosmic ray population. The dependence of both types of equilibrium anisotropies on the energy and the velocity of the particles and on plasma velocity are shown to be in agreement with the theoretical predictions. The amplitude of the large field aligned anisotropies observed earlier in the event is found to be independent of the rise time of the event and to vary as (Vt)–1.Interplanetary magnetic sector crossings during a flare event, cause abrupt changes in both the amplitude and phase of the non-equilibrium anisotropy whereas they have no significant effect on equilibrium anisotropy. The effect of azimuthal density gradients on the decay time constants of flare enhancements are also examined in an attempt to understand the complicated structures, often observed, in the time intensity profiles at low energies.Part of this work was done while the author was at the University of Texas as Dallas, U.S.A.Now at the National Academy of Sciences, Washington, D.C. 相似文献