Consequently, if the rotation of the planet leads to a common zonality of the envelopes, we can conclude that: the climatic and tectonic life of the planet is subject to this same latitudinal zonality. This third-order regularity is implied by the first two.
The third regularity can be explained only in terms of an interaction between the terrestrial envelopes, under conditions where the masses of each envelope move at their own particular velocities, so that motions of different phase appear along the rotation axis of the Earth (that is, perpendicular to the latitudes). It is obvious that, if the veloci ties of motion of the envelopes are different, the atmosphere and hydrosphere will affect them. Certain conclusions can be drawn from this. The evolution of the Earth's solid crust can be explained most simply on the basis of the law of gravity, by assuming it to be a consequence of this law under the given conditions of planetary rotation, and orogenesis can be explained in the same way. Moreover, this same law of gravity and motion of the gravitating masses explains the motion of the atmosphere.
It is not possible, on the other hand, to explain the motion of the atmosphere purely in terms of the thermal conditions. Similarly, thermal conditions cannot account for the structure of the Earth (although hitherto it has been almost universally accepted that they could). However, both these phenomena can be explained by the combined effects of the rotation of the Earth and gravity. Phenomena originating in the atmosphere can be accounted for more by the structure of the atmosphere itself than by the radiant energy of the Sun and its influx; in any case, this atmospheric structure must not be ignored.
How deeply into the Earth does this common zonality of the body of the planet extend? Apparently very deeply indeed, since it applies not only to the [outer] lithosphere but also to the barysphere [centrosphere] and the mantle as well.
Earthquakes and seismic surveying tell us a great many things about the interior of the Earth. As pointed out by Morain (1927), the latitudinal distribution of earthquakes indicates an increase in seismicity at the 35th parallel and at the equator. According to Lichkov (1929), the zonality of
earthquakes is associated with the rotation of the Earth and thus correlates well with the zonality of epeirogenic movements. This also pertains to the most ordinary shallow earthquakes with hypocenters at depths of around 30 km.
Stoyko (1952) states that deep-focus earthquakes with hypocenters at depths greater than 70 km show their relation to the Earth's rotation most clearly. He confirmed the special seismicity of the regions around the 35th parallel and the equator, and he found a definite correlation between deep-focus earthquakes and fluctuations in the angular velocity of the Earth's rotation. Stoyko explained this correlation in terms of the special state of the interior of the Earth in these regions, and he assumed that the frequent earthquakes appearing as a consequence of this special state indicate a variation in the velocity of terrestrial rotation.
However, it may be more logical to take the point of view stated by us previously, according to which in this case we have to do with something other than a special critical state of the material of the Earth which causes changes in the volume of this material. As Eigenson (1954) has pointed out, the variation in rotational velocity is apparently a result of the action of external repulsive forces. Seismic phenomena, according to this interpretation, are a unique means of relieving the excess stresses which we referred to above when discussing the regions of the subcrustal layer. Deep faults in the Earth's crust are confined to the 35th parallel, and consequently the genesis of these planetary faults is related to the rotation of the Earth (Sel'skii, 1949).
It is quite clear that deep-focus earthquakes in the Tethys region and in its continuation into Asia are confined to focus depths of the order of 300 km. Obviously, in this case the effect of the Earth's rotation will reach to this depth, producing latitudinal structures. In Europe the results of this effect show up down to depths of no more than 100 to 120 km. Faults are in all probability related to deep-focus earthquakes.