Japan sits at the juncture of three major tectonic plates, Pacific, Euroasian and Philippine. The Hakone volcano is above a triple juncture point. Monitoring the surface expansion of this structure is crucial to understanding the subsurface plate dynamics and the risks to local people from volcanic eruption, earthquake and tsunami events.
The Hot Springs Research Institute of Kanagawa Prefecture constantly monitors this volcano with respect to the surrounding ground using a combination of EDM, GPS and Tilt meter technology.
The two automated laser systems consist of motorized Leica DI3000 EDM units housed in a ruggedized structure with power backup. These constantly measure slant ranges corrected by accurate meteorological measurements to a number of prisms located throughout the caldera. All measurements are data based to provide a time line data set of the ground surface expansion.
The four GPS systems were originally Trimble 4000SSE units using Trimble post-processing software. In October 2001, Akasaka Tec based in Yokohama, Japan replaced this system with four Leica SR530 GPS units, a telephone modem network and CRNet™ software. This provides the Institute with superior GPS measurement quality and the ability to automatically alarm should a slant range exceed an operator defined limit. Additionally, all GPS determined vector solutions and raw data are now stored in a modern database structure for easier playback and analysis.
The combination of Leica EDM and Leica GPS in an integrated real time monitoring system will help make Kanagawa Prefecture a safer place.