In order to obtain the absolute vertical rates at all
benchmarks, we link levelling data with tidal records.
Kato and Tsumura (1979) have developed a method to
evaluate absolute crustal movements from tidal records.
Using this method, the average uplift rates over the period
from 1981 to 1995 at Maisaka, Omaezaki and Yaizu tidal
stations are estimated to be 3.8 ± 0.6, –7.0 ± 0.5, and
–6.9 ± 0.7 mm/yr, respectively. The linear rate of Omeazaki
station was used as a known value for adjustment of the
levelling network, because this station has long history
and high accuracy.