Researchers say the estimated run-up height of the tsunami following Monday's massive earthquake in central Japan was over 4 meters in the Noto Peninsula.

A group led by Associate Professor Ishiyama Tatsuya of the University of Tokyo's Earthquake Research Institute began surveying the northwestern coast of the peninsula on Tuesday.

The group found that tsunami in Ishikawa Prefecture potentially surged inland to a height of about 4.2 meters at the Akasaki fishing port in Shika Town where a maximum seismic intensity of 7 was recorded.

The tsunami's height was assessed based on traces of water on exterior walls of buildings and debris that had washed ashore.

The height of tsunami on the coast is not known because there were no tide gauges. But it is generally believed to be less than half as high as waves that run inland.

The survey also found that the ground rose at several points along the coast. It rose about 25 centimeters at Akasaki harbor.

The ground was elevated by over 3 meters at multiple locations about 10 kilometers to the north.

It rose about 3.9 meters at Kaiso fishing harbor in Wajima City and about 4.1 meters at another port in the city about 5 kilometers to the north.

Researchers identified traces of tsunami at the ports where ground levels rose sharply, but they say the water did not reach any buildings.

Ishiyama says tsunami probably reached residential districts in areas where the co-seismic coastal uplift was small.