The Kushigata Range active fault zone is located at northeastern margin of the Echigo (Niigata) plain, central Japan, its length is 16 km and its mean vertical slip rate is about 0.2 to 0.4 m per 1000 years. We excavated two trenches across the Kajikawa fault, one of the Kushigata Range fault zone. Three faulting events are identified at both two trenches. The latest faulting occurred between BC1,200 and BC520, penultimate events was between BC4,850 and BC3,635, and the earlier event was between BC9,210 and BC7,330. Vertical slip of the latest and penultimate events are 0.7 m and about 1 m. Timing of the latest event is concordant to that of liquefaction event observed at the archaeological cites in the northern part of the Echigo (Niigata) plain.
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