The radiolarian fossil assemblage from one rock sample usually comprises numerous species. Based on the data of occurrence from several horizons in a continuous stratigraphic section, range of each species could be estimated. When a species does not find from a mid horizon but occurs from the below and the above horizons, the species is regarded as existence as an interpolated species in the mid horizon.
Therefore, the total specific number from the mid horizons increases by adding the supplemented numbers to the actually occurred numbers. However, the specific number of the lowermost and uppermost horizons remains only actually occurred numbers. We must think over this "supplementary effect" in the mid horizons.
We made a model of steady faunal change on the basis of the following conditions: specific number, origination rate, extinction rate and detection rate in each horizon are independently constant through a section, and the time interval between horizons is constant. Using this model, we can estimate the specific number in any horizons. Comparing the actual data with this model, the pattern of origination and extinction is discussed on Late Permian and Middle Jurassic samples. It seems that radiolarians steadily flourished during Late Permian time, and the decrease trend toward the end-Permian is not detected. It seems that the origination rate of radiolarians increases in Middle Jurassic time.

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During progressive simple shear deformation, linear elements rotate so that there is a tendency of all the linear elements to align themselves parallel to the direction of the bulk shear. The amount of rotation may thus be considered as a fundamental measure of the degree or intensity of shearing, i.e. by how much the shearing has progressed or advanced. This (i.e. the degree or intensity of shear deformation) has been expressed here by identifying two parameters rotation angle (θ) and coefficient of rotation (ω) that give an idea of the degree or intensity of shear deformation at two or more points of a shear zone, especially in a comparative way.

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[in Japanese]

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