Underground temperature survey at one meter depth was conducted at the Minazuki landslide in Ishikawa Prefecture with the purpose of investigating the flowing channels of the water infiltrated from a spring and a pond which exist in the upper part of the landslide area. Parts of low temperature proLably caused by the flow of ground water were determined after the effect of various factors have been taken off from the obtained data. As a result of the investigation, it was found that the parts, which originate from the spring and/or pond, join together at the flat land of the upper part of the area and part into three zones; near the northern boundary of the area and the central part as well as near the southern boundary of the area; those three zones extend separatedly toward the toe of the slope.
If each low temperature zone assumed to be caused by the flow of ground water with a large filtaration velocity (about 2.1× 10^-1cm/sec) and a lower temperature (12.20° C) as compared with those in the usual ground at one meter depth(22.12° C), it is probable that a vein of ground water exists under each zone. Among three veins, three veins of the northern side and the central part were convinicingly evidenced by tracer method for ground water. And the existence of the vein of the southern side is highly probable, as there are a small landslide and springs at an extension of the zone.
The scale of those veins were calculated with the aid of θ _z=1y diagrams. As a result of those calculations, it war shown that each vein had their top between six and seven metrs depth and that the sizes of them were increasingly greater toward the north.

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The purpose of this study is to clalify the characteristics of groundwater and base runoff small basins composed of relatiuely unconsolidated sediment of the Osaka group. The auth in carried out observations of groundwater levels, stream discharges, and precipitation fro orm middle June,1975 to late March,1976.
At first, the variations of groundwatr level and the characteristic of base runoff are studied. There are two aquifers in a basin. The groundwater levels in a main aquifer do not always reflect the rainfall pattern. The groundwater level in the main aquifer is found to be proportional to the amount of base runoff during dry periods. From the change in the height of groundwater storage and the groundwater runoff from the main aquifer, the amount of groundwater recharge is estimated weekly, and the characteristics of base rnuoff relative to the groundwater recharge are examined.
The base runoff is found to change according to the magnitude of groundwater recharge, and does not necessarily decrease exponentially during dry periods.

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