重力ポテンシャル差計としての光格子時計の地球物理応用の可能性

摘要

Relativistic geodesy using optical lattice clocks based on direct measurement of the gravity potential is expected to improve a static geoid model serving as the reference of height. On the other hand,in plate subduction zones like Japan where crustal deformation is active, time variations in the gravity potential caused by tectonic phenomena are not negligible. In this paper,geopnysical impacts of monitoring temporal potential changes with a relative precision of 10-18 are discussed. Measured potential variations are much more sensitive to height changes of observation sites than to the underground mass redistributions. This means that optical lattice clocks allow us to evaluate accuracy of GNSS-derived height changes and to monitor rapid movement of crustal fluids such as magma, combined with gravity measurement.