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931.
M. G. LAIRD 《Sedimentology》1968,10(2):111-120
Curved or planar discordant surfaces occurring within a limited stratigraphic range immediately beneath shallow marine deposits represent penecontemporaneous shear surfaces along which slumps have moved. Rotated packets of strata frequently retained within the curved discordant surfaces show both internal and external evidence of having moved laterally. Movement is considered to have been triggered off by a sudden shock or shocks which may have been either of sedimentary or tectonic origin. The slumping occurred at the change in gradient between slope and shallow marine shelf deposits.  相似文献   
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The historical development of analytical aerial triangulation block adjustment is mentioned by way of introduction. The advantages of separating the plan and height adjustments are given and the observation equations of a typical adjustment section are analysed to show that this convenient practice is justified in normal circumstances. The principles of a direct solution of the normal equations suitable for a moderate-sized computer, are explained and developed in detail for the height adjustment. The advantages of tie-strips in the height adjustment are demonstrated and the difficulties which then arise are discussed. An approximate method which overcomes these difficulties is developed. Details of the computer programmes used are given in Appendix B.  相似文献   
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Summary The process of radon diffusion in space and time through rocks is treated in detail from the point of view of radiometric prospecting for oil. Taking into account the depth and diffusivity conditions encountered in nature it is stated that vertical radon diffusion reaching from the oil deposits up to the surface cannot be expected. Time intervals as required for setting in of a stationary concentration state and decay conditions of the radon lead to the conclusion that the penetration of emanometric measurements seldom exceeds the depth of 5–10 m.  相似文献   
938.
Summary In this study the different forms of the electromagnetic field strength recordings at the Thera-Crete microwave line of link are examined, in comparison with the corresponding weather situations prevailing over that area. According to the amplitude of fluctuations, the different forms of recordings have been classified in three basic typesA, B, C and the annual frequency of the appearance of these types has been observed. Finally, the influence of weather situations on radio wave propagation was examined and it has been found that in most cases a close relationship exists between weather situations and the different fading forms of the electromagnetic field so that a prediction of the fading form be possible by means of the weather forecast.This study was sponsored by a research grant from NATO's Scientific Committee.  相似文献   
939.
Summary The validity ofBoltzmann's energy distribution law as applied to the charge distribution of monodisperse aerosols, i.e. aerosols which contain particles of one size only, was studied with improved equipment now available.Since monodisperse aerosols with particle size of about 10–6 cm cannot yet be produced and because aerosols in general contain particles of different sizes, polydisperse aerosols stored in a large gasometer were used for the investigation. The composition and the average radius of these aerosols heterogeneous in particle size were determined by the Exhaustion Method employing a diffusion battery without end-pieces or connecting tubing.The experimental curve found for the ratio of the uncharged (N 0) to the charged (N) nuclei versus radius (r) of the particles deviates for all investigated radii between 0.5 and 4.0·10–6 cm from the theoretical curve of a monodisperse aerosol computed according to the Boltzmann law. For radii smaller than about 1.4·10–6 cmN 0/N is smaller than that given by Boltzmann's law, for radii greater than 1.4·10–6 cm larger, or, in other words, forr<1.4·10–6 cm the number of charged nuclei found in the aerosols investigated is greater than that predicted byBoltzmann's law, and forr>1.4·10–6 cm smaller.The deviations from the theoretical curve forr>1.4·10–6 cm can be fully explained by the polydispersity of the aerosols used; forr<1.4·10–6 cm the deviations are too big to be attributed to polydispersity. From this it must be concluded thatBoltzmann's distribution law is not valid for the charge distribution of homogenous aerosols containing nuclei with radii smaller than about 1.4·10–6 cm.The equivalent radius as deduced from a substitute monodisperse aerosol in charge equilibrium for which theBoltzmann law is assumed valid, deviates in the range of 1.0·10–6<r<3.0·10–6 cm (or 90%>100N 0/Z>55%) on the average by up to 35% from the actual mean radius of the investigated polydisperse aerosols computed from the radii of their singly sized components.
Zusammenfassung Die Gültigkeit desBoltzmannschen Gesetzes der Energieverteilung für die Ladungsverteilung von monodispersen Aerosolen, das heisst Aerosolen, welche Teilchen von nur einer Grösse enthalten, wurde mit den jetzt zur Verfügung stehenden verbesserten Mitteln studiert.Da monodisperse Aerosole mit Teilchengrössen von ungefähr 10–6 cm noch nicht erzeugt werden können und Aerosole im allgemeinen Teilchen von verschiedenen Grössen enthalten, wurden für die jetzige Untersuchung polydisperse Aerosole, welche in einem grossen Gasometer gespeichert waren, benützt. Die Zusammensetzung und der mittlere Radius dieser Aerosole mit heterogener Teilchengrösse wurden nach der Exhaustions-Methode unter Benützung einer Diffusionsbatterie ohne Endstücke oder Verbindungsröhren bestimmt.Die experimentell gefundene Kurve, welche das Verhältnis der ungeladenen (N 0) und geladenen (N) Kerne als Funktion des Radius (r) darstellt, weicht für alle untersuchten Radien zwischen 0.5 und 4.0·10–6 cm von der theoretischen Kurve eines monodispersen Aerosols, wie sie nachBoltzmann's Gesetz berechnet wird, ab. Für Radien kleiner als ungefähr 1.4·10–6 cm ist das VerhältnisN 0/N kleiner als es durchBoltzmann's Gesetz gegeben wird, für Radien grössen als 1.4·10–6 cm grösser oder, mit anderen Worten, fürr<1.4·10–6 cm ist die Zahl der geladenen Teilchen, die in den untersuchten Aerosolen gefunden wurde, grösser als die vonBoltzmann's Gesetz vorausgesagte, und fürr>1.4·10–6 cm kleiner.Die Abweichungen von der theoretischen Kurve fürr>1.4·10–6cm können vollkommen durch die Polydispersität der benützten Aerosole erklärt werden; fürr<1.4·10–6 cm sind die Abweichungen zu gross, als dass sie der Polydispersität zugeschrieben werden könnten. Daraus muss geschlossen werden, dassBoltzmann's Verteilungsgesetz für die Ladungsverteilung eines homogenen Aerosols, welches Kerne mit Radien kleiner als ungefähr 1.4·10–6 cm enthält, nicht gültig ist.Der äquivalente Radius, wie er von einem im Ladungsgleichgewicht befindlichen, monodispersen Ersatz-Aerosol, für welchesBoltzmann's Gesetz als gültig angenommen wird, abgeleitet werden kann, weicht im Bereich von 1.0·10–6<r<3.0·10–6 cm (oder 90%>N 0/Z>55%) durchschnittlich bis zu 35% vom tatsächlichen mittleren Radius des untersuchten polydispersen Aerosols ab.


The research reported in this article has been supported in part by the Geophysics Research Directorate of the Air Force Cambridge Research Laboratories, through the European Office of the Air Force Research Division, United States Air Force under Contract AF 61(052)-26, by the United States Department of Army, through its European Research Office, Contract DA-91-591-EUC-1282 & 1657 and by the Instrumentation Engineering Physics & Analysis Laboratory of the General Electric Co., Schenectady, New York under Retainer Agreement.  相似文献   
940.
Summary The effect of thickening of the crustal layer in mountainous region on the dispersion curve of Love waves has been studied. Perturbation method has been applied to obtain the modified frequency equation for Love waves through the surface of separation between a semi-infinite material and a layer the thickness of which abruptly increases throughout a certain length of the path. The effect is to decrease the phase velocity of the waves particularly in the low period range. It has been pointed out that by proper study, the amount of thickening may be obtained.  相似文献   
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