The gravitational anomalies of simple bodies (sphere, cylinder, and fault) were used to develop methods for analyzing gravity data in the frequency domain. The Fourier transforms of the functional representations of the theoretical gravitational anomalies of these bodies were obtained. Mathematical relations were formulated between the transform‐versus‐frequency relationships and the depths and sizes of the bodies. Compound gravity anomalies (multiple cylinders, fault, and cylinder) were analyzed, and the transforms were reduced to transforms of anomalies due to individual simple bodies. These methods of analysis were applied to theoretical anomalies using numerical techniques, and the accuracy of both depth and size determinations was within a few percent in all cases.
Relationships between electrical and thermal conductivities of consolidated sandstone rocks and sediments were investigated. Equations given by Archie (1942) and Woodside and Messmer (1961) were combined to give an equation which relates the two conductivities for the rocks. Equations relating conductivity and porosity, given by Maxwell (1881), Bruggeman (1935), and Woodside and Messmer (1961) were combined to give two equations which relate thermal and electrical conductivities for sediments. Data from 65 rock samples and 105 sediment samples (including data for 37 rock samples published by Zierfuss and Van der Vliet, 1956) were use establishing the reliability and parameter values of the equations. The derived equations can be used to determine thermal conductivities from electrical conductivities providing thermal conductivities of the solid constituents can be approximated. For samples of sandstone rock, deviations of the data from values predicted by the equations are shown to be related to the variations in composition of the samples. Within the accuracy of the data, the thermal conductivities of sediment samples seem to be controlled more by the water content than by the mineral composition.
Four seismograms obtained during 1958 and 1959 from large quarry blasts at Promontory (1,221,000 and 2,138,000 Ib of explosive) and Lakeside, Utah (1,500,000 Ib), and the underground Blanca nuclear explosion (38,000,000 Ib equivalent) near Mercury, Nevada, were studied to ascertain whether converted waves of PS type were recorded and, if so, whether they could be used in an analysis of earth crustal layering, as proposed by Andreev in 1957. The PS converted wave is presumed to be composed principally of the SV‐type wave (vertically polarized shear wave) and to result from the conversion of energy from the parent compressional P wave at the interface between two crustal layers of contrasting seismic velocity. The method of analysis consisted in computing theoretical times of arrival for PS converted waves based on crustal layering and velocities in the area as determined from refraction seismic studies by Berg, Cook, and Narans [1959], by plotting the radial horizontal component versus the vertical component of velocity of ground motion over appropriate time intervals, and by comparing amplitudes and frequencies of the PS converted waves with the amplitude and frequency of the parent P wave. Arrivals, provisionally interpreted as PS converted waves, were detected on the traces of both the radial horizontal‐component seismometers (2 cps natural frequency) and the vertical component seismometers (2 cps). The amplitude of the PS converted waves was usually several times greater than that of the first arrival of the P wave. The successively later arrivals of PS converted waves from successively deeper horizons showed progressively greater ground‐velocity amplitudes, as found by Andreev on earthquake seismograms, but some variance from this generalization was found. The frequencies of the various PS converted wave arrivals were approximately the same as those of the parent P wave, between 5 and 10 cps. The crustal layering, which was determined by using the times of arrival of the PS converted waves, compared favorably with that given by Berg, Cook, and Narans for this area. The computed depths of the successive layers were: 5.5, 9.7, 16, and 26 km at Neola, Utah (epicentral distance of about 245 km from Lakeside blast); 12, 26, and 31 km at Gold Hill, Utah (173 km from Promontory); 8.6, 24, and 29 km, also at Gold Hill (379 km from Blanca); and 12, 22, and 31 km at Elko, Nevada (279 km from Promontory).
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