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Интеллектуальная Система Тематического Исследования НАукометрических данных |
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State of the problem. It has long been observed that the northern parts of global submeridional structures are displaced to the west relative to their southern parts. This refers primarily to four “channel” structures spaced about 90° apart in longitude; these define the geometrical symmetry of the tectonic plan of the Earth, namely the Mid-Atlantic Ridge, the Mid-Indian Ridge, the Western Pacific subduction zone, and the East Pacific Rise (if we consider the small Juan de Fuca spreading system as a northern extension of the latter). In addition, North America relative to South America and the northern Atlantic coast of Africa relative to its southern part are characterized by displacement to the west. Such a global structural pattern creates the impression of “twisting” of the Earth; that is, the clockwise movement of the Northern Hemisphere relative to the Southern Hemisphere, when viewed from the North Pole. If such a relative displacement occurred, then it means, in the tectonophysical aspect, that some sinistral shear movement has been functioning in the Earth’s lithosphere. Without attempting a comprehensive broad generalization, we present some examples, showing sinistral shear “twisting” of the Earth relative to the axis of its rotation. Some examples of “twisting” of the Earth in the geologic past: (1) the above mentioned displacement of the northern parts of the global submeridional structures to the west relative to their southern parts; (2) the counterclockwise rotation of the “geodynamic pair” of Siberia-Laurentia in Proterozoic; (3) the sinistral displacement of the Northern Hemisphere relative to the Southern Hemisphere after the break-up of the last Pangaea; (4) the oblique orientation of the global network of planetary fracturing; (5) the eastword declination of the axis of submeridional compression; (6) Baikal rift as a “megarupture” by the sinistral latitudinal shear; (7) the sinistral “beveling” of geophysical fields; (8) the dextral “twisting” of Venus. All these examples confirm the idea of possible sinistral “twisting” of the Earth. The cause of such “twisting” is unclear, although it is likely connected with the Earth’s rotation around its axis. Conclusions. The above examples support the possible sinistral “twisting” of the Earth suggested by many authors. The cause of such a “twisting” is still under discussion. It can be due to the combination of the northern drift of the Earth’s core with the differential rotation of the mantle layers around the Earth’s axis, a different velocity of rotation of the Northern and Southern Hemispheres around the Earth’s axis, or a general tendency of galactic matter towards vortex twisting. At the same time, some of these examples show that many paleomagnetic reconstructions can be usefully considered in the tectonophysical aspect, which may lead to the development of a new scientific field, named “paleomagnetic tectonophysics”.