Tectonophysics

a branch of tectonics that studies the physical conditions of the occurrence of tectonic deformations, such as folds and faults, in rock layers.

Tectonophysics uses the findings of physics and mechanics regarding the plastic deformation and fracture of solid bodies to study large-scale deformations occurring in parts of the earth’s crust of nonuniform (for example, granular or stratified) structure. Because tectonic deformations develop gradually over long periods of time, tectonophysics must trace all stages in the plastic deformation of rocks and in the growth of faults in rocks. In addition, tectonophysics takes into account the characteristic crustal conditions under which the deformations occur—for example, the influence of gravity, of hydrostatic pressure, and of increased temperature gradients. The ultimate aim of tectonophysical research is to establish the genesis of observed tectonic structures, which formed in the stress fields that existed in the crust in earlier times. The importance of tectonophysics stems from the circumstance that an understanding of the mechanism of formation of tectonic structures will make it possible to predict the patterns of their distribution in the earth’s crust.

The methods of tectonophysical investigation are based on (1) the reconstruction of ancient tectonic stress fields for individual regions or the crust as a whole in accordance with the data of structural analysis and (2) the experimental reproduction of tectonic structures under laboratory conditions through the use of models. The second approach is founded on the principle of physical similitude and uses natural rocks or equivalent materials, such as silicone, clay, bitumen, petroleum oils, and gelatin.

The term “tectonophysics” was introduced by the Soviet geologists V. V. Belousov and M. V. Gzovskii in 1954. In the USSR, problems of tectonophysics are studied at the Institute of Litho-sphere Physics of the Academy of Sciences of the USSR and Moscow State University (V. V. Belousov and others), at the Institute of Geological Sciences of the Academy of Sciences of the Kazakh SSR (E. I. Patalakha and others), and in the experimental tectonic laboratory of the Institute of Geology and Geophysics of the Siberian Division of the Academy of Sciences of the USSR (I. V. Luchitskii and others). Problems in tectonophysics are discussed at sessions of the International Geological Congress and are the subject of special international symposia.

In the USSR, work in tectonophysics is published in the periodicals Geotektonika (Geotectonics) and Izvestiia AN SSSR: Seriia fizika Zemli (Proceedings of the Academy of Sciences of the USSR: Physics of the Earth). The international journal Tectonophysics has been published in the Netherlands since 1964.