In this paper the author obtained a theoretical formula of waves generated by a vibrating bottom with a circular form. Substituting some numerical values into this formula, he gave a figure of variation of the wave height for one cycle vibration of the bottom. And he also found that an out-going wave disappears for values of x=a₀r₀ which satisfy
x·J₁′(x)-J₁(x)=0,
where r₀: a radius of the vibrating region,
a₀: a wave number of the out-going wave,
J₁(x): Bessel function of the first order.
A curve of the last equation versus r₀ was also presented.

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In this paper the author obtains theoretical formulas ((30) and (31)) of waves generated by a vibrating bottom with an elliptic form, and also an asymptotic formula ((32)) of an out-going wave far from the wave-generating source, an amplitude variation of which versus a direction is shown in Fig. 2 for the following numerical values, i. e.,
a depth of water (H)=31.2cm,
a period of a vibration of the botton (T)=1sec.,
an acceleration of gravity (g)=980.5cm/sec²,
a length of major axis (x₀)=70cm,
a length of minor axis (y₀)=50cm, }(Fig. 1)
an amplitude of vibration of the bottom (D′_bot)=1cm.
The author (1962a, 1962b) has already treated a problem on water waves generated by a vibrating bottom with an infinite rod (or a circular form). Then he has found that an out-going wave disappears when a₀x₀ (or a₀r₀) satisfies a functional relation, where a₀ is a wave number of the out-going wave and 2x₀ (or 2r₀) a width (or a diameter) of the vibrating region of the bottom. This phenomena is due to an interference of waves generated at each point in the vibrating region. This effect can also be seen in this paper. Amplitute variation of the out-going wave versus a direction has thus an anisotropy relevant to the lengths the major and the minor axis, and the ecentricity of the ellipse. This anisotropy of the amplitude variation is not parallel with the form of the vibrating ellipse. In Fig. 2, remark able variation of a wave height can be seen for an ellipse small eccentricity.

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§ 1. Geographycal distribution of seismic activities over the whole world. Main seismic belts of the world. Geographical distribution of big earthquakes. Geographical distribution of intermediate and deep earthquakes. Vertical distribution of earthquake foci in the profile across seismic belts. Crustal and Subcrustal or upper-mantle earthquakes. Types of seismic belts of the world. (Oceanic type, Island arc type, orogenic-zone type, and continental-platform type.) Sub-division of seismic zones into minor seismic regions.
§ 2. Three-dimensional distribution of seismic activity in and near Japan. Three dimensional distribution of earthquake foci in and near Japan. Earthquake provinces defined by C. Tsuboi and the relations among them seen from stereometric distribution of foci belonging to each of them.
§ 3. Regionality of magnitude frequency relation of earthquakes. Characteristic behaviour of magnitude-frequency relation of big earthquakes in the main seismic belts of the world. Coefficient b of Gutenberg-Richter magnitude-frequency relation log N=a+b (8-M) and its geotectonic implications.
§ 4. Relations between geotectonic structure and seismicity in and near Japan. Island arcs meeting around Japan. Constitution of Honshu Arc. Seismo-tectonic zoning of Japan and her vicinity.
§ 5. Cycle of geotectonic development and its bearing on seismicity Relation between coefficients a and b in Gutenberg-Richter magnitude frequency formula. Geotectonic situation of seismic regions of the world represented in the a-b diagram. A proposed scheme of cycle of geotectonic development and development of seismic activity.

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