Geophysical Abstracts 152 January-March 1953

VOLCANOLOGY 51
14356. Thomson, Andrew, and Bremner, P. C. Permafrost drilling and soil-tem­
perature measurements at Resolute, Oornwallis Island, Canada: Nature,
v. 170, no. 4330, pp. 705-706, 1952.
Temperatures have been measured in 2 drill holes, 307 and 453 feet deep. The
average conductivity of core samples was determined by Misener as £=0.006 cgs
units at 31.2 C. Short period fluctuations in the temperatures at the 8-inch level
reflect fluctuations of air temperatures, but are damped out and become practi­
cally negligible at 60 inches. Seasonal temperature changes are perceptible to
about 50 feet with a lag of about 6 months. Complete freezing of the active
]ayer was observed to take place in about 3 weeks. Temperatures at 98, 300, and
450 feet are practically constant at 13.50, 11.59, and 9.54 C respectively.
The layer between 50 and 98 feet is nearly isothermal. M. O. R.
VOLCANOLOGY
14357. Werenskold, W. Faults and volcanoes: Am. Geophys. Union Trans., v.
34, no. 1, p. 110, 1953.
It is suggested that temperature and pressure in the earth's crust are so adjusted
that no melting occurs except in special cases although the temperature is near
the melting point. Movement along a vertical fault would disturb this balance;
below the uplifted flank pressure would be lowered so that melting, and sub­
sequent lava flows, might result. M. C. R.
14358. Imbo, Giuseppe. Temperature d'irrigidimento di attuali lave etnee [The
temperature of solidification of the present day lavas of Etna]: Accad.
sci. fls. et mat Napoli Rend., ser. 4, v. 18, p. 18-21,1951.
During the eruption of Etna of November 25, 1950, the temperature of ejected
lava was measured, and the temperature of solidification was found to be 635 C,
some 30° lower than in some recent eruptions. As in some previous studies, the
temperature of solidification was found to be related to the whole process of
eruption, its total duration, and to the presence or absence of explosive phe­
nomena preceding and accompanying the eruption. 8. T. V.
TECTONOPHYSICS
FORCES IN THE EARTH AND OROGENESIS
14359. Scheidegger, Adrian E. Examination of the physics of theories of
orogenesis: Geol. Soc. America Bull., v. 64, no. 2, p. 127-150, 1953.
This is a review of the theories of orogenesis from the viewpoint of the physicist.
The principal conclusion is that all theories of orogenesis must remain purely
speculative until more factual data about the earth are known. M. C. R.
14360. Bullen, K. E. On strain energy and strength in the earth's upper mantle:
Am. Geophys. Union Trans., v. 34, no. 1, p. 107-109, 1953.
Considerations of strain energy suggest that either the Gutenberg-Richter
magnitude formula gives the energy of large earthquakes too great by a factor
rather greater than ten, or that the fracture resisting strength of the material
in the focal region of the greatest deep earthquakes is at least of order 500
kg/cm3 . It is suggested further that SR%, where $ denotes the breaking