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1.
Eruptions of the active Karymsky stratovolcano began about 5300 (6100 14C) b.p. from within a pre-existing caldera which formed 7700 14C b.p. As indicated by 32 14C determinations on buried soils and charcoal, the volcano has gone through two major cycles of activity, separated by a 2300 year period of repose. The first cycle can be divided into two stages (6100–5100 and 4300–2800 b.p.). The earlier stage began with especially intense eruptions of basaltic andesite to dacite. The later stage was characterized by moderate-strength eruptions of andesite. The second cycle, which is characterized by weak to moderate intermittent eruptions of andesite, started 500 b.p. and continues to the present. Eruptive patterns suggest that this cycle may continue for at least another 200 years with an eruptive character similar to that of the recent past. 相似文献
2.
Summary Theoretical considerations are put forward for identifying the Dynamic and Static Methods of Diffusion measurements of aerosol particles. On the basic of this equality the Exhaustion Method of Diffusion developed byPollak andMetnieks for the size-frequency resolution of a heterogeneous aerosol by Dynamic Diffusion Methods should be applicable to Static Methods. This hypothesis is tested using a Pollak-Nolan nucleus counter as decay vessel. It is shown that turbulence in the counter is the most serious obstacle against this type of approach to finding the size components of an aerosol. The time involved, the high humidity in the counter and a hypothetical nucleus-free zone are other major difficulties for relatively large Aitken nuclei. It is established, however, that for particles whose diffusion coefficient is of the order of 10–3 cm2 sec–1, the proposed method should be quite workable. 相似文献
3.
Summary In this paper an attempt has been made to analyse the World shallow focus earth-quakes by the method ofGutenberg andRichter. Frequency-magnitude analysis of various earthquakes indicate that in the relation logN=a–b M, the ratio (b/a)–1 satisfies fairly well the seismicity of a region and it is felt that this ratio may be used as a measure of seismicity for a given region. 相似文献
4.
Summary The study of heat exchanges or temperature changes in the surface layers of the soil are important in agricultural science at tropical latitudes. The quantity, thermal diffusivity largely determines the temperature change produced in any layer of the soil when heat is conducted there from an adjacent layer. Therefore, the authors have determined the thermal diffusivity of the soil from range and lag methods suggested byJohnson andDavies [15]2) andCoutis [7] respectively. The values of diffusivity cbtained from these methods agree well with each other. The effect of soil moisture on diffusivity has been studied. The diffusivity increases with the increase of moisture in the surface layers of the scil. The ratio of ranges of soil temperature at different depths is found to be approximately constant which is in agreement with the theory of heat flow into the soils. The results of diffusivity obtained from these methods agree well with those results of past workers. The mean value of the thermal diffusivity of red sandy soil at the experimental site of Waltair is found to be 6.336×10–3 cm2/sec. 相似文献
5.
Estimation of in-situ hydraulic diffusivity of rock masses 总被引：1，自引：0，他引：1
Victor C. Li 《Pure and Applied Geophysics》1984,122(2-4):545-559
A method of estimating in-situ hydraulic diffusivity of rock masses by means of well-injection history and frequency of induced seismicity is presented. The method is based on the diffusion of injected fluid from a spherical cavity in a poroelastic half-space and the effective stress theory, as proposed byTerzaghi (1925, 1936) andHubbert andRubey (1959). Application of the method to two different regions, one in western New York and the other in Japan, resulted in estimated diffusivities of the order 103 and 104 cm2/sec, respectively. These values lie within the range of published estimates of in-situ diffusivity by other means, a summary of which is presented in tabular form. The calculated diffusivities suggest that the characteristic time of fluid diffusion is close to 0.1, rather than unity, as is sometimes assumed in the literature. 相似文献
6.
Subhas Dutta 《Pure and Applied Geophysics》1965,60(1):51-60
Summary The possibility of propagation of Rayleigh waves in an incompressible crust of constant density and rigidity varying exponentially with depth lying on a semi-infinite transversely isotropic base has been discussed in this paper. Frequency equation has been derived and numerical calculations are made. The result obtained in this case is compared with that ofNewlands [3]2) andDutta [4]. 相似文献
7.
Irving Michelson 《Pure and Applied Geophysics》1965,61(1):149-151
Summary As a preliminary calculation of the Equilibrium Theory of Tides, a fictitious Earth-Moon configuration is analyzed byThomson andTait [1]2), in which non-sphericity of oceans is attributed to the attraction exerted by a stationary Moon. A rise of level is found at the which Earth-Moon orbital motion is accounted. This feature, which is utterly contradictory to fact according toG. H. Darwin [2] prompted him to remark that the equilibrium theory is nearly as much wrong as possible, in respect to the time of high water. An elementary analysis is given which, in demonstrating an exactly opposite finding, suggests a manner of removing one of the long-standing obscurities of the Laplace theory, remarked upon byHough andAiry, and in recent times byC. Eckart [3]. 相似文献
8.
Dr. Adrian E. Scheidegger 《Pure and Applied Geophysics》1954,28(1):75-90
Summary Investigations have shown that in groundwater- and oil-bearing strata there are preferential directions of flow that are often maintained over wide areas.Johnson & Hughes (1948, see Ref.) analysed a series of oil well cores by cutting them into small horizontal plugs and they obtained directional permeabilities which they plotted in the form of polar graphs. They were not able to give a physical explanation of this phenomenon. On the other hand, there exists a theory of permeability in which the latter is represented as a symmetric tensor. This theory has been developed byFerrandon (1948, see Ref.), but no experimental substantiation of it seems ever to have been attempted.In the present paper, the author undertakes to compare the two sets of findings. FromFerrandon's theory, the directional permeabilities (denoted byk) corresponding to the experiments ofJohnson & Hughes are calculated and it is shown thatk
–1/2 if plotted as polar graph, should form an ellipse. The data ofJohnson & Hughes are then are drawn. In this manner, a substantiation of the tensor theory ofFerrandon is obtained.
Published by Permission of Imperial Oil Limited, Calgary, Alberta (Canada). 相似文献
Zusammenfassung Untersuchungen der Permeabilität von Grundwasser und Erdöl führenden Gesteinsschichten haben gezeigt, dass dieselbe in vielen Fällen richtungsabhängig ist. Hierbei bleibt die Richtung extremaler Permeabilität oft über weite Gebiete konstant.Johnson & Hughes untersuchten eine Reihe von Bohrkernen von Oelquellen auf Richtungsabhängigkeit der Permeabilität. Hierzu schnitten sie aus denselben kleine, waagrechte Stücke, bestimmten deren Permeabilität und stellten das Ergebnis ihrer Messungen in der Form von Permeabilitätspolardiagrammen dar. Sie waren nicht im Stande, eine theoretische Erklärung der erhaltenen Kurven zu geben. Auf der anderen Seite existiert eine Theorie der Permeabilität, wobei die letztere als symmetrischer Tensor behandelt wird. Diese Theorie wurde vonFerrandon vorgeschlagen; es scheint aber, dass keine experimentelle Bestätigung davon je versucht worden ist.In der vorliegenden Arbeit vergleicht der Verfasser die zwei Typen von Untersuchungen. Nach derFerrandon'schen Theorie wird die «gerichtete» Permeabilität (mitk bezeichnet), die den Experimenten vonJohnson & Hughes entspricht, berechnet. Es wird gezeigt, dassk –1/2, als Polardiagramm dargestellt, die Gestalt einer Ellipse haben sollte. Die Resultate vonJohnson & Hughes werden dann in die Form vonk –1/2 umgerechnet und als entsprechende Polardiagramme dargestellt. In dieser Weise wird eine experimentelle Bestätigung der Tensortheorie vonFerrandon erhalten.
Published by Permission of Imperial Oil Limited, Calgary, Alberta (Canada). 相似文献
9.
B. D. Dore 《Pure and Applied Geophysics》1968,71(1):118-131
Summary A formula is derived for the spatial attenuation of the two possible modes of oscilation of a two-layer, rotating system. If the long-wave approximation is made, it is found with reference to the internal mode that this formula disagrees with an earlier result obtained byRattray [8]2). 相似文献
10.
Richard S. Lindzen 《Pure and Applied Geophysics》1965,62(1):142-147
Summary The response of the atmosphere to a diurnally oscillating thermal drive, asymmetric with respect to the equator, is investigated. It is found that the solutions ofLaplace's tidal equation do not form a complete set; all of them being orthogonal to the associated Legendre polynomial,P
2
1
(cos ), being the latitude. As an extension ofLaplace's theorem for gravitationally excited ocean tides to thermally driven atmospheric tides, it is shown that a diurnal drive whose latitude dependence is given byP
2
1
gives rise to no surface pressure oscillation. 相似文献
11.
Takashi Ichiye 《Pure and Applied Geophysics》1966,63(1):179-195
Summary A layer of a few hundred meters thickness with suspended matter (a nepheloid zone) was discovered byEwing andThorndike [4]3) near the bottom on the continental slope of the North Atlantic. A downward pressure gradient is produced in this layer due to increment of water density with suspensoid. When only the Coriolis force balances with this pressure gradient, a bottom nepheloid current flows southwestward parallel to the depth contours with a velocity of about 10 (cm/sec) for a slope of one degree. The pressure gradient for fluid with locally variable density above a sloping bottom is treated and an extra term due to density gradient along the slope is derived. The vertical profiles of the nepheloid current with an effect on the vertical eddy viscosity are computed. Two kinds of vertical distributions of eddy viscosity are determined from the observed nepheloid distributions and used in the calculations: constant but different values at two layers and those increasing with height. The effect of the change of density along the bottom is treated by introducing dimensionless variables. Rossby number of the nepheloid current becomes about 10–2 indicating inertia terms to be negligible. Rossby number of turbidity currents ranges from 2 (in a decaying area) to 5 (developing area), suggesting that inertia terms are more important than Coriolis terms. The trajectories of turbidity currents are computed from motion of a mass of mud under the Coriolis force and friction, and the results are applied to those inferred byHand andEmery [6] in the San Diego Through off California.LGO Contribution Number 925. 相似文献
12.
Summary The study of radiative transfer in clouds and fog requires a knowledge of basic radiation constants. For this purpose the volume extinction, scattering, and absorption coefficients, the maximum absorption coefficients for composite spectral lines, and the coefficients used to expand the phase function into a series of Legendre polynomials for analytic representation of the phase function are provided in tabular and graphical format. The analysis for cloud droplets is based upon the rigorous electromagnetic theory. All Mie computations are carried out in an exact manner avoiding any approximations. Absorption line constants as computed here are based upon the investigations ofElsasser withCulbertson [5]3) andWyatt, Stull, andPlass [18]. Tabulations are made on the basis of fifty spectral intervals covering the entire solar and infrared spectra. Polarization effects are disregarded in this study. 相似文献
13.
E. O. Holopainen 《Pure and Applied Geophysics》1967,67(1):156-165
Summary The annual mean distribution of the surface stress curl over the Northern Hemisphere has been estimated from the horizontal vorticity advection in the atmosphere by using the upper-wind statistics as published byCrutcher [2]3). The results are used to compute the wind-driven mass transport (Sverdrup transport) in North Atlantic and North Pacific. The calculated intensity of the Gulf Stream is largest at the latitude 35°N, where a mass transport of 45×106 tons sec–1 is obtained; for the maximum intensity of the Kuroshio current a value of 60×106 tons sec–1 is obtained.Research supported in part by the Section of Atmospheric Sciences, National Science Foundation, Grant GP-2561.The research for this study was started by the author at the Department of Meteorology and Oceanography, The University of Michigan, Ann Arbor, Mich. 相似文献
14.
Gopinath Sarkar 《Pure and Applied Geophysics》1967,66(1):37-47
Summary The displacement due to vertical impulsive load has been obtained by function theoretic method. Graphs have been drawn for horizontal as well as for vertical displacement. It has been shown thatPekeris's [12]2) method is easier to apply than that ofCagniard [2] for the same purpose. 相似文献
15.
Jay S. Fein 《Pure and Applied Geophysics》1977,115(5-6):1493-1500
The large-scale terms in the vorticity equation are evaluated usingKrishnamurti's (1971a, b) summer mean winds at 200 mb for a global belt from 25°S to 45°N. The production of vorticity by the divergent wind field is found to be imbalanced over all of the tropical and subtropical belt. As a result there is a requirement for a sub-grid scale (space or time) mechanism which removes negative vorticity from the regions of strong divergence (Tibetan and Mexican highlands) and removes positive vorticity from the regions of strong convergence (mid-oceanic troughs) at 200 mb during northern summer at a rate of approximately 4×10–10 sec–2. As suggested byHolton andColton (1972), in regions of strong and persistent convection, such as the Tibetan Plateau, deep cumulus clouds can account for this transport. However, the mechanism for removing positive vorticity in the vicinity of the upper tropospheric mid-oceanic troughs is still an intriguing and open question.On leave-of-absence at the National Science Foundation, Climate Dynamics Research Section. 相似文献
16.
Nirmal Kumar Sinha 《Pure and Applied Geophysics》1969,73(1):47-59
Summary The aim of this paper is to study the propagation of love-type waves in a homogeneous half-space overlain by a heterogeneous crust with various types of heterogenety. Frequency equations are obtained in each of the cases and numerical calculations are done in some cases and the results thus obtained are compared with those done byJeffreys andMitra [3]2). 相似文献
17.
Prof. Dr. Georg Wüst 《Pure and Applied Geophysics》1952,21(1):7-18
Summary Recent research, and particularly that undertaken by the «Kieler Institut für Meereskunde», has suggested a re-examination of the water households of both the Mediterranean and the Baltic Seas. It is hoped that a comparative study of the two may contribute to a better understanding of the maritim-meteorological and oceanographic characteristics of either sea. The latest rain maps byW. Daume, F. Möller, andW. Brogmus show an average annual amount of rainfall of 345 mm in the Mediterranean, and 474 mm in the Baltic. In both cases these figures are roughly 15 per cent lower than what authors have so far assumed them to be. The figures for the fresh-water sypply from the land have also been revised in recent publications byDaume andBrogmus, the annual figures for the Mediterranean being 350 km3 (i. e. 129mm in hight), while the annual figure for the Baltic is 480 km3 (i. e. 1243 mm in hight). These figures have been used together with recent, but still largely hypothetical, figures for the difference between in- and outflow at the straits (Gibraltar, Bosphorus, the Belts, and the Sound), to calculate the evaporation from the basic water-household equation. The annual evaporation figure is 1450 mm for the Mediterranean, and only 473 mm for the Baltic. Again, these figures differ from former estimates, but they are confirmed by other considerations, and calculations of maritime meteorology. It is with these new figures in mind that the author finally goes into the question of the hydrographic and climatic effects of a damming-up of the above-mentioned straits.Soergel's fantastic «Atlantropa» project, already criticised bytroll, van Einerm andDaume, is briefly treated from the point of view of the water household and is found to be largely impracticable. It is pointed out that the systematic collection of further information on the meteorological and oceanographic conditions of the two seas is urgently needed for the sake of further reducing the margin of error in the above calculations.
Zusammenfassung Auf Grund neuerer, besonders auch im Kieler Institut für Meereskunde durchgeführter Untersuchungen wird der Versuch gemacht, die Wasserhaushalte des Mittelländischen Meeres und der Ostsee einer Revision zu unterziehen und durch eine vergleichende Betrachtung zu einem vertieften Verständnis der maritim-meteorologischen und ozeanographischen Besonderheiten beider meere beizutragen. Aus neuen Regenkarten vonW. Daume, F. Möller undW. Brogmus ergibt sich die mittlere Niederschlagshöhe für das Mittelmeer zu 345 mm/Jahr und für die Ostsee zu 474 mm/Jahr, das sind in beiden Fällen um rd. 15% niedrigere Werte, als frühere Autoren vermuteten. Auch für die Süßwasserzufuhr vom Lande werden im Anschluss an die neuen Arbeiten vonDaume undBrogmus neue Zahlen geboten: für das Mittelmeer 350 km3/Jahr (=129 mm/Jahr Wasserhöhe), für die Ostsee hingegen 480 km3/Jahr (=1243 mm/Jahr Wasserhöhe). Unter Benutzung dieser Zahlen und neuerer z.T. zwar noch sehr hypothetischer Angaben über die Differenz von Ausstrom und Einstrom in den ozeanischen Verbindungsstraßen (Straße von Gibraltar, Bosporus, Belte und Sund) wird die Verdunstung aus der Grundgleichung des Wasserhaushaltes rechnerisch ermittelt und für das Mittelmeer zu 1450 mm/Jahr, für die Ostsee hingegen zu nur 473 mm/Jahr gefunden, Werte, die von früheren Schätzungen abweichen, aber auch durch andere maritim- meteorologische Ueberlegungen und Berechnungen gestützt werden können. Zum Schluss wird die Frage der hydrographischen und klimatischen Auswirkung der Abdämmung der genannten Meeresengen vom Standpunkte dieser neuen Wasserbilanzen kritisch geprüft. Das phantastische «Atlantropa»-ProjektSoergels wird im Anschluss an die kritischen Betrachtungen vonTroll, van Einerm undDaume vom Standpunkte des Wasserhaushalts kurz beleuchtet und seine Durchfürhung in grossen Teilen als unmöglich angesehen. Weitere systematische maritimmeteorologische und ozeanographische Beobachtungen werden für beide Nebenmeere als dringend erwünscht bezeichnet, um die in dem Bilanzen noch bestehenden Unsicherheiten weiter zu verringern.相似文献
18.
D. A. Tanner 《Pure and Applied Geophysics》1972,97(1):111-126
Summary In a recent paperHunt andTanner [3]2) investigated the waves generated by a steadily moving two-dimensional pressure distribution, which was zero ahead of the disturbance and a constantp
0, tehind it, these regions being joined smoothly by a cubic function. Only those solutions with supercritical flow in both regions were considered, these were found to lead to an asymmetric solitary wave.This result is now extended to take account of the possibility of subcritical flow in either or both the regions, that is when there is a cnoidal wave train either behind and or ahead of the main solitary wave crest.The wave profiles are determined by the iterative method employed in the previous paper. This together with the wave drag associated with each system is computed for various values ofp
0/U
2, where is the fluid density andU a typical velocity. 相似文献
19.
G. J. Day 《Pure and Applied Geophysics》1955,31(1):169-181
Summary The measurement of condensation nucleus concentration from an aircraft is considered and preliminary observations made with a photo-electric condensation nucleus counter discussed. It is concluded that at heights up to 6000 ft concentrations of condensation nuclei vary, from 200 cm–3 in clean maritime air to 5 × 103 cm–3 generally over large industrial areas and 35 × 103 cm–3 downwind of specific industrial sources. It appears that sea spray makes a contribution to the nucleus population.Mr. G. J.Day, B. Sc., Meteorological Research Flight, Royal Aircraft Establishment,Farnborough, Hants. (Great Britain). 相似文献
20.
Walter Rau 《Pure and Applied Geophysics》1956,33(1):114-120
Zusammenfassung Die für die Erzeugung von Salzteilchen aus dem Meer wesentlichen Vorg?nge werden untersucht, wobei die Teilchen nachVittori nachgewiesen und vermessen werden. Es zeigt sich, dass Zerplatzen von aufsteigenden Luftblasen allein wenig wirksam ist.
Dagegen nimmt die erzeugte Teilchenzahl mit wachsender Zersprühgeschwindigkeit rasch zu. Dichten von 106 pro cm3 durchgeblasener Luft sind leicht realisierbar. Die Ergebnisse werden im Hinblick auf die für und wider dieK?hler’sche Hypothese vorgebrachten Argumente und auf die tats?chlichen Chloridgehalte der Atmosph?re diskutiert.
Dr.W. Rau, Max-Planck-Institut für Physik der Stratosph?re,Weissenau (Würtibg.). 相似文献
Summary The processes essential for the production of salt-particles from the sea are investigated, the particles being identified and measured according toVittori. Bursting air bubbles are shown to be mostly ineffective. The number of produced particles increases rapidly with accelerating velocity of spraying. Populations of 106 per cm3 of air blown through the water are possible. The results are discussed with regard to the arguments stated pro and contra the hypothesis ofK?hler and to the chlorid contents of the atmosphere.
Résumé Les facteurs essentiels pour la production de particules de chlorure de sodium hors de la mer sont examinés en indiquant et mesurant les particules selon la méthode deVittori. L’éclatement des bulles d’air ascendant dans l’eau est démontré être peu efficace. Le nombre de particules produits s’augmente très vite, si la vélocité de jaillissement s’accro?t. On peut aisément réaliser des densités de 106 par cm3 d’air soufflé. Les résultats sont discutés en vue des arguments constatés pro et contre l’hypothèse deK?hler et de la quantité de chlorure, contenue effectivement dans l’atmosphère.
Dr.W. Rau, Max-Planck-Institut für Physik der Stratosph?re,Weissenau (Würtibg.). 相似文献