Abstract
Seafloor displacements need to be measured continuously to monitor seafloor stability during methane hydrate production. Ground displacement at an onshore landslide site is usually monitored using instruments such as slide sensors. These instruments measure relative displacements between a fixed point and measuring points in the landslide mass. However, they cannot be used for monitoring displacement at the seafloor where it is difficult to establish a fixed reference point.
In this study, we propose a new method for monitoring seafloor displacement using a 3-component servo-accelerometer system. The basic concept of the proposed method is to calculate displacements from double integrals of acceleration waveform records. Theoretically, a velocity waveform is obtained from a single integral of an acceleration waveform, and displacement is obtained from double integrals of an acceleration waveform. One of the most important points in data processing is to reduce noise, especially long-period trends, which produce many errors in integral calculations.
