摘要:

A small rocket magnetometer has been developed for use in investigation of electrical currents in the ionosphere. In three flights near the magnetic equator electrical currents were detected. The equatorial electrojet was found to consist of at least two layers of electrical current, one layer near an altitude of 100 km and the other 20 to 25 km higher. A current flowing in the opposite direction to the main electrojet current was found to the north of the electrojet.

ISSN:0148-0227    

DOI:10.1029/JZ064i005p00489

年代:1959

数据来源: WILEY

摘要:

The world‐wide character of the intensity changes in meson and nucleon components is shown by a study of data from Ottawa, Churchill, and Resolute during the period October 1956 to December 1957. Further discussion is essentially restricted to the mean nucleonic component derived from the three stations. The investigation reveals an association between transient decreases in cosmic‐ray intensity and the central meridian passage of active solar regions. On an average, the greater the activity rating of the regions, the larger is the cosmic‐ray decrease. It is not possible, however, to discuss the relation specifically in terms of the characteristics of the regions, such as flares, sunspots, and the like. Further support for the relation comes from observation of geomagnetic data. Attention is drawn to the similarity between small as well as large transient decreases in intensity with regard to presence or absence of recurrence tendency. The study supports the view that both the 27‐day variation and the Forbush events differ only in degree and could therefore be attributed to the same mechanism. It is possible to attribute the cosmic‐ray decreases to beams of ionized rarified gas emitted from the sun and differing considerably in their charac

ISSN:0148-0227    

DOI:10.1029/JZ064i005p00505

年代:1959

数据来源: WILEY

摘要:

Measurements of the radon‐decay products in the atmosphere over a 6‐year period have been made with a monitor which precipitates fine airborne particulate matter onto a moving metallic tape. A calibration of the apparatus showed that the mean value for radon content at Socorro, New Mexico, is 2.4×10−13curie/liter, with an average diurnal fluctuation of a factor of 3.1 between maximum and minimum values. The diurnal variation is attributed to the amount of vertical mixing due to eddy diffusion in the lower atmosphere. The gustiness in air motion near the ground is taken as a measure of the mixing that occurs, and it is measured with a hot‐wire anemometer. An annual variation in the atmospheric radioactivity is found which gives values during the fall months that are about twice those during the spring. This variation can also be explained in terms of the mixing that occurs at low levels as judged from mean wind‐speed data. Values for the coefficient of vertical diffusion are calculated from measurements of the exhalation rate of radon from the ground and the concentration of radon near ground level as determined from the monitor data. The mean value of the height‐independent diffusion coefficient is 6.7×104cm2/sec. Maximum values of as high as 55×104cm2/sec are found in the late afternoon of the month of April. Minimum values of the order of 2.0×104cm2/sec are found in the early morning hours in

ISSN:0148-0227    

DOI:10.1029/JZ064i005p00521

年代:1959

数据来源: WILEY

摘要:

Climax Observatory spectograms of the green coronal line, λ5303, for the period 1942–1944 near solar activity minimum have recently been remeasured. Analysis of these revised intensities indicates that the most consistent feature in the relation of green line intensity to geomagnetism is a minimum in geomagnetic activity following central meridian passage (CMP) of regions of high green line intensity. This effect may be interpreted as a result of the tendency of solar activity regions to coincide with regions of high green line intensity and to avoid M regions. In the period October 1953 to October 1954, at sunspot minimum, no relation appeared between green line intensity and geomagnetic activi

ISSN:0148-0227    

DOI:10.1029/JZ064i005p00527

年代:1959

数据来源: WILEY

摘要:

Thermal microstructure formations, coincident with the occurrence of flushing in a narrow Puget Sound embayment, have been observed and measured with a high‐sensitivity probe. Accompanying the larger formations which extend horizontally for thousands of yards, a microstructure is shown to exist which consists of elongated layers extending hundreds of yards with temperature differences of less than 0.1°C. Two series of isothermal diagrams constructed from vertical temperature measurements taken in the area during winter and summer flushing are presented to show the manner in which such formations are develop

ISSN:0148-0227    

DOI:10.1029/JZ064i005p00533

年代:1959

数据来源: WILEY

摘要:

Five frequency distributions were compared for their ability to fit maximum rainfall values in Illinois. Analyses were performed on both seasonal and annual maxima for storm periods of one to ten days. Calendar‐day rainfall amounts from 39 stations for the 40‐year period, 1916–1955, provided the basic data for the study. Initially, an evaluation was made of frequency relations based upon individual station data. This evaluation indicated that more reliable results would be obtained by determining average relations based upon data from several stations within an area. Consequently, the state was divided into four sections having approximate storm rainfall homogeneity. Next, average frequency relations based upon each of the five frequency distributions were determined for each section and storm period. Statistical tests indicated no marked superiority for any one of the distributions. Comparisons were made between results obtained from the methods of moments and least squares in data fitting. It was concluded that differences obtained between the two methods are insignif

ISSN:0148-0227    

DOI:10.1029/JZ064i005p00541

年代:1959

数据来源: WILEY

摘要:

The problem of water table fluctuations in response to repeated recharges is considered. The effect on the water table of intermittent constant recharge (recharge applied intermittently at a constant rate) and of intermittent instantaneous recharge (recharge applied instantaneoulsy at regular intervals) is analyzed in detail. The final results are shown to consist of a combination of periodic and transient components; the transients are monotonic decreasing functions.The theory may be applied to problems of ground‐water flow through aquifers and to land drainage problem

ISSN:0148-0227    

DOI:10.1029/JZ064i005p00549

年代:1959

数据来源: WILEY

摘要:

A simple numerical method for analyzing observations of drawdown in the neighborhood of a pumped well is described. It makes use of the ratio of the values of the drawdown at any two times and a graph computed from the theory. It has the advantage over existing procedures in that it is available for the analysis of isolated results and for small values of the time. The same method is applicable to the determination of thermal conductivity and practical examples of both cases are given.

ISSN:0148-0227    

DOI:10.1029/JZ064i005p00561

年代:1959

数据来源: WILEY

摘要:

G‐wave velocities for continental and oceanic paths do not differ by more than about 2 percent. Since the G‐wave velocity is controlled by the low velocity zone in the mantle, this zone is present beneath continents and oceans. This suggests that the composition and distribution of temperature are the same for depths greater than about 50 km under continents and oceans. The low velocity zone may be the source of the primary basaltic magma and could account for the long‐period nature of S waves. It may also represent a zone of decoupling for relative movements between crust and mantle.Love waves with long propagation paths recorded with long period seismographs are used to infer that the mean value of continental crustal thickness lies in the range of 32 to

ISSN:0148-0227    

DOI:10.1029/JZ064i005p00565

年代:1959

数据来源: WILEY

摘要:

Thermoluninescence as modified by pressure has been studied, and a relationship between pressure effects and geologic age has been observed. Experimental evidence indicates that the amount of pressure and the length of time that it is applied cause a marked variation in the ratio of thermoluminescence of pressed to unpressed samples. Geologically young samples showed a greater variability in the induced time‐pressure effects than did geologically older samples.The ratio of thermoluminescence of pressed to unpressed samples plotted against the time the pressure was applied showed a systematic variation from low values through a pronounced maximum and back to intermediate values. The amplitude of this curve shows an inverse relationship to the geologic age of the sample for limestones younger than Mesozoi

ISSN:0148-0227    

DOI:10.1029/JZ064i005p00569

年代:1959

数据来源: WILEY