If one axial symmetry is assumed, three components of the displacement can be generally devided into two groups. One corresponds to the displacement of
SH wave and the other does to the displacement made of
P and
SV waves in rectangular coordinates. The general rule has been obtained which finds displacement potentials φ and φ, including the following conditions: displacement pontentials must be the solution of the wave equation of
P and
S waves and the displacements made of φ and φ should satisfy the equation of motion.
The well known displacement potentials in rectangular and cylindrical coordinates are reduced to the special cases of the general rule. In the present paper the displacement potentials in spherical coordinates have been given by the general rule. Displacement potentials in different coordinates can be related to each other.
The density of energy flow has been expressed with the displacement potential in the general coordinates. Energy flows of spherical waves will be easily calculated by the use of the displacement potentials in spherical coordinates. Energy flows exist not only in radial direction but also in direction of the latitude. The flows in lateral direction mean diffracted waves.
The origin of φ does not always coincide with that of φ, as in case of reflected
S and
P waves. The expression becomes very complicated as to energy flows due to the interferences of
P and
S waves.
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