THERMAL CONDUCTIVITIES OF ROCKS 271 



Report of Four Years' Study of Earth Temperatures in Wells. 



By Charles E. Kern. 

 The Oil and Gas Journal, Tulsa, vol. 29, No. 33, 193 1, pp. 54 and 104. 



This report, made to the American Petroleum Institute, covers four years 

 of work to indicate a possible method for assisting in the location of oil 

 domes. 



The recording of earth temperatures undertaken with the financial support 

 of the American Petroleum Institute has been under the general supervision 

 of van Orstrand, who initiated, about ten years ago, the geothermal method 

 for locating oil domes. 



Temperature tests taken in approximately 350 oil wells in Texas, Okla- 

 homa, California, and New Mexico have served as foundations for drawing 

 maps and diagrams. They show the relation between temperature and 

 structure in many instances. 



The difficulties in interpreting thermal readings are discussed. 



The Cooling and Temperature of the Earth. 



By B. Gutenberg. 



Sonderdruck aus dem Handbuch der Geophysik, vol. 2, 1929, 35 pp. Gbriider 



Borntrager, Berlin. 



This special reprint from the Handbook of Geophysics, vol. 2, contains 

 two chapters dealing with the temperature phenomena of the earth : 



Chapter 1. Facts based on observations. 



Chapter 2. Theoretical considerations. 

 The following items are discussed in chapter 1 . 



1. Measurement of temperature inside the earth's crust. — Means of 

 measurement are explained and figures showing the results of a series of 

 measurements are given. 



2. The geothermal degree. — Tables showing the geothermal degrees in 

 various countries and at various depths are given, and the causes of the 

 variation of these degrees are discussed. 



3. Heat conductivity of rocks. — Two tables, one showing the heat con- 

 ductivity as a function of humidity and amount of pores in the rocks and 

 another giving the figures for the heat conductivity of several rocks, as 

 established by various authors, and curves showing the dependency of the 

 heat conductivity on the temperature (according to Wolff) are added. 



4. Specific heat of rocks. — Figures for a few rocks are given. 



5. Melting temperature and melting heat. — A table with figures for the 

 constants of melting curves, according to Wolff, and a melting curve for 

 helium, according to Simon, are given. 



6. Temperatures of lavas ; transformation-temperatures. — Lava tempera- 

 tures according to Perret, Day, Jaggar and Shepherd are collected in a 

 table. 



7. Radioactive substances and the production of heat by them. — Two 

 tables showing (1) the production of heat according to the amount of Ra, 

 Th, and K in rocks, and (2) showing the radioactivity of Vesuvius lavas 

 according to Joly are given. In chapter 2, ' Theoretical considerations,' the 

 author discusses : 



8 . The cooling of the earth during the pre-geological epochs. 



9. The cooling of the crystalline earth crust and the temperature resulting 



