摘要 |
PROBLEM TO BE SOLVED: To provide a displacement observation method capable of accurately observing displacement when the displacement of the sea surface or the ground surface is observed by using a GPS.SOLUTION: A displacement observation method uses, when the displacement of the sea surface is observed by a GPS tsunami gauge 1 which is an observation station having a GPS receiver, a corrected precision calendar delay-corrected by a device such as a satellite clock/electric wave transmitter for a satellite clock error included in an IGS precision calendar. The position of a reference point 2 in a main reference station network 3A is measured by using auxiliary information obtained at two auxiliary reference station networks 3X and 3B arranged at a place different from that of the main reference station network 3A to obtain correction information provided to the tsunami gauge 1 in an area A to be an observation target. When the obtained position of the reference station 2 is displaced, the correction information obtained at the main reference station network 3A is determined to be invalid. |