Tago 642/119 RLR(1983) is 11.6m below BM Attach-31
Documentation added 2009-05-05
Data 1999 onwards appears to be slightly higher than previously.
Documentation added 2012-02-22
A massive earthquake magnitude 9.0 occurred at 14.46 JTS (05.46 UTC) on Friday 11th March 2011 with the epicentre situated approx. 70km east of the Oshika Peninsula of Tohoku. It was the largest earthquake ever to hit Japan triggering a tsunami with waves of up to 40.5m and travelling up to 10km inland.
Documentation added 2014-03-13
The GPS benchmark information has been downloaded from the SONEL website. GPS benchmark P114 is 14.073m above RLR.
Geographical Survey Institute Kitasato -1 Tsukuba-shi Ibaraki-ken 305