摘要:

After a brief review of what is already known about the whole Earth, from the upper limit of the atmosphere at several hundred miles above the surface down to the very center at a depth of four thousand miles, attention is called to six of the particularly baffling problems in geophysics. These are: The origin of mountain chains; the origin of geosynclines, that is to say, the great troughs or depressions that existed during geologic times at various places on the Earth, that by filling with the products of erosion washed down from adjacent land areas are intimately associated with the great deposits of limestone, shale, and sandstone, often amounting to several miles in thickness; the cause of igneous activity, including volcanism, a group of phenomena that continue to give us striking evidence of a hot and active interior of the Earth; the origin of deep‐focus earthquakes, that is, the ones caused by some still mysterious processes at depths of as much as four hundred miles below the surface; the origin of the Earth's magnetic field about which much is known, but of which the underlying cause is still uncertain; and the temperatures prevailing in the interior of the Earth, a knowledge of which would provide a clue for solving many other problems. It is urged that more effort be devoted to scientific investigations in the several branches of the physics of the Earth, utilizing all possible theoretical as well as experimental method

ISSN:0002-8606    

DOI:10.1029/TR028i005p00673

年代:1947

数据来源: WILEY

摘要:

This paper presents the results and methods employed to obtain a geographical position in the polar regions from measured zenith distances of the sun during periods of continuous daylight.

ISSN:0002-8606    

DOI:10.1029/TR028i005p00680

年代:1947

数据来源: WILEY

摘要:

This paper explains the method used to adjust the arcs of triangulation in North and South Dakota by simultaneous adjustment. The least‐squares adjustment of 836 equations and 1913 v s or corrections was accomplished with no serious difficulty and gave satisfactory correction

ISSN:0002-8606    

DOI:10.1029/TR028i005p00683

年代:1947

数据来源: WILEY

摘要:

On October 8, 1946 an earthquake was felt throughout an area of about 25,000 square miles in eastern Missouri, western Illinois, and northwestern Kentucky. The data obtained from 691 questionnaires returned show that: (1) The shock was felt over a wide area but was not of destructive intensity; (2) the felt area as a whole was almost circular in shape; (3) the region of stronger intensities was eccentric to the total felt area, being toward the south; (4) near the epicenter the earthquake noises were described as sharp and of short duration while at greater distances the noises were described as rumbling and of long duration. The epicenter determined from seismographic data is in southeastern Iron County about midway between the towns of Chloride and French Mills, Missouri (37°28′N, 90°34′W; H = 01h12m02.5SU.T.). This point is roughly 50 miles northwest of the New Madrid seismic district. The epicenter is in the vicinity of the Hogan fault which is postulated as delineating the southwest side of the structural block of the St. Francois Mountains (the major structural and physiographic unit of the northeastern Ozark Highl

ISSN:0002-8606    

DOI:10.1029/TR028i005p00687

年代:1947

数据来源: WILEY

摘要:

The horizontal pendulums of the seismograph at the University of Texas have been equipped with McComb‐Romberg “pick‐ups.” Instead of recording directly, the light from the pick‐up mirror falls on a split photo cell; the current from this photo cell is amplified and sent through the recording galvanometer. The output of the amplifier is also fed to an auxiliary circuit which controls the intensity of the recording light so that its brilliance is approximately proportional to the speed with which the galvanometer spot

ISSN:0002-8606    

DOI:10.1029/TR028i005p00691

年代:1947

数据来源: WILEY

摘要:

This paper describes common errors that are often disregarded in the securing and application of wind‐speed data, obtained by the use of the conventional rotating‐cup anemometer. The magnitudes of the errors, as determined by computation and from extensive field tests in the Salt Lake Desert, are discussed, and their importance in various types of meteorological work is briefly considered. Some remedial measures are summarily outli

ISSN:0002-8606    

DOI:10.1029/TR028i005p00696

年代:1947

数据来源: WILEY

摘要:

So far as the writer has been able to determine, some of the rather voluminous data here presented are the first of their kind ever obtained through continuous registration. In addition to values of solar and sky energy received on various surfaces, simple formulas have been evolved to enable the reader to calculate the amount of solar energy to be expected on vertical surfaces facing south. Auxiliary tables should facilitate the calculation of the angle of the Sun's rays on a south vertical surface at any hour and on any day at various latitudes.

ISSN:0002-8606    

DOI:10.1029/TR028i005p00705

年代:1947

数据来源: WILEY

摘要:

The use of radar to measure rainfall quantitatively was proposed. A hypothetical radar installation on Santiago Peak, California, was examined as a tool for determination of rainfall intensities over the whole of the Los Angeles coastal drainage basin. It was stressed that research should be undertaken that would be aimed toward a correlation between the image of an A‐oscilloscope or a PPI‐scope and the corresponding isohyetal pattern derived from observed rainfall data. A new table classifying precipitation intensity relative to average drop size, drop distribution, terminal speed of fall, and liquid water content of the air was presented (see Table

ISSN:0002-8606    

DOI:10.1029/TR028i005p00713

年代:1947

数据来源: WILEY

摘要:

The recurrence tendency in magnetic character figures is evaluated by auto‐correlation coefficients for various intervals up to 83 days for each year from 1890 to 1944, The strength of the 27‐day recurrence pulse varies during the 55 years, being generally strong from about two years after sunspot maximum through the minimum year. Evidence for persistent recurrence intervals other than multiples of about 27 days is very weak. The magnitudes of the correlation coefficients for short intervals indicate that the time unit of geomagnetic activity is two to three days. Formulas for the prediction of magnetic character figures by the method of least squares are based on the mean auto‐correlation coefficients for intervals of 1, 26, 27, 28, and 54 days for stages of the sunspot cycle with weak and strong recurrence conditions. A prediction formula with a non‐linear term is also

ISSN:0002-8606    

DOI:10.1029/TR028i005p00715

年代:1947

数据来源: WILEY

摘要:

An investigation to determine the extent to which underwater pressure recordings may be used to characterize sea‐surface conditions has been in process during the past six months. On the basis of information derived from consistent photographic recordings of sea‐surface patterns and simultaneous underwater pressure records at Woods Hole and Bermuda, it appears possible to derive the average interference pattern of the sea surface from the underwater recordi

ISSN:0002-8606    

DOI:10.1029/TR028i005p00722

年代:1947

数据来源: WILEY