Determination of swelling in addition to clay mineralogical composition is important to clarify the contribution of clays on the occurence of landslide . The clay fractions (<2μm) separated from landslide areas of Okinawa (Shimajiri mudstone), where the contribution of clay was estimated to be relatively low, contained clay mica, smectite and chlorite as dominant clay minerals . The smectite content was relatively low with a value of about 30%, and its swelling was again low . On the other hand, the clay fraction separated from landslide area of Kamenose, Osaka, where the contribution of clay was estimated to relatively high, contained about 90% of smectite and its swelling was high.

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The possibility of application of one-meter-depth temperature measurement for investigating groundwater vein streams in Jawa and Taiwan was examined by measuring one-meter-depth temperature and temperature of flowing groundwater in some landslide areas in both countries on April 1982.
As a result of this investigation, next matter are shown:
1) Normal one-meter-depth temperature (θ_u) and temperature of flowing groundwater (θ_w) are influenced by elevation and latitude in Japan, but both temperature in Jawa and Taiwan are influenced only by ele vation of each investiaated area. The relation between θ_u and θ_w was shown in Table-3.
2) Converted values into elevation of zero meter of θ_u are 29.8°C in Jawa and 25.3°C in Taiwan and the values of θ_w are 26.3°C in Jawa and 22.6°C in Taiwan. These values in both countries are very higher than those in Japan. θ_u and θ_w in both countries lower 0.5°C per 100 meters. This fall rate is a little lager than that of Japan on April (0.45°C/100m).
3) Difference between θ_u and θ_w is 2.7-4.2°C in Jawa and 0.9-3.5°C in Taiwan in this investgating time. Application of investigation by measuring of one-meter-depth temperature is possible in every landslide areas in J awa, but this application is not possible in a part in Taiwan.
4) The effectiveness of this investigating methode was shown at Cianjur Seratan in Jawa and Jiau Lin Pyng and Lung Tan in Taiwan (Figs. 8 and 9).

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