Articles | Volume 372
https://doi.org/10.5194/piahs-372-217-2015
https://doi.org/10.5194/piahs-372-217-2015
12 Nov 2015
 | 12 Nov 2015

Liquefaction-fluidization induced land subsidence: impact of the 2011 Tohoku earthquake on reclaimed land around Tokyo bay area, Japan

A. Kagawa, K. Furuno, T. Kusuda, Y. Sakai, T. Yoshida, and O. Kazaoka

Abstract. The 2011 Tohoku earthquake caused major liquefaction-induced, ground deformation of the reclaimed land surrounding Tokyo Bay. In this area, liquefaction was visibly manifest by sand boils, ejection of sandy water, land subsidence and floating underground tanks. The level measurements show a correspondence between the degree of liquefaction-fluidization and the amount of subsidence. The strata most susceptible to liquefaction are hydraulically emplaced dredged fill and artificial strata on thick uncompacted Holocene deposits. On the other hand, the phenomena of seismic isolation coursed by liquefaction had saved the single-family houses from collapse.