Evaluation of the Background Seismic Noise Level of the Buried Seismometers Installed by Two Caisson Installation Technique

Two caisson installation technique were conducted in the construction of DONET (Dense Oceanfloor Network System for Earthquakes and Tsunamis); one is using piston core technique [1], and the other is vibration hammer technique [2] that is developed to install the caisson using ROV. This paper describes the background noise level of seismometers installed by two caisson installation technique are discussed.