Rainfall and runoff were monitored in 10 th small catchments underlain by Granitic rock basins and Mesozoic sedimentary rock basins upstream of Ibi River in Gifu Prefecture. Following findings were obtained (1) Runoff peak response time (it's time lag) is longer in Mesozoic sedimentary rock basins than in Granitic rock basins. (2) Large changed runoff duration curve were obtained only in P 1 and P 2 catchments of Mesozoic sedimentary rock basins. Runoff characteristics of Granitic rock basins are one pattern, but these of Mesozoic sedimentary rock basins are two patterns. This suggests that Granitic rock basins are enough to obtain one basin, but Mesozoic sedimentary rock basins are not enough to do it.
