Geophysics in war and peace

Geophysics is the science dealing with physical processes or facts related to the Earth, to its solid body as well as to the water and the atmosphere. It may be divided into general geophysics, the study of geophysical problems for reasons primarily scientific, and applied geophysics which is concerned with problems of economic or military importance [see "References" at end of abstract, Gutenberg, 1937]. As geophysicists investigate problems covering the whole Earth, international cooperation is highly important. On the other hand, cooperation with other sciences, especially geology, geochemistry, and astronomy, is necessary. Geodesy is closely related to geophysics, and sometimes is considered a part of it or combined with it in "geonomy." Knowledge of the fundamental problems of physics is required of a geophysicist. Details depend on the particular problems; the theory of elastic waves plays an important role in many investigations; the theory of gravitation, electricity, magnetism, optics, and other studies in other fields, In applied geophysics, familiarity with fundamental problems of electrical engineering (electronic devices in instruments) is essential.