2:50 PM - 3:05 PM
[SGD03-05] Construction of a laser-strainmeter network for accurate seismic and geodetic observations
Keywords:strainmeter, laser, crustal deformation, Kamioka, Inuyama, Tenryu-Funagira
At Kamioka site, two laser strainmeters with baselines of 100m and 1500m are in operation [2, 3]. At Inuyama and Tenryu-Funagira sites, a 30-m strainmeter and a 400-m one are installed, respectively . These strainmeters clearly detect earth tides, and their amplitudes are consistent with the calculation based on the tidal force, the standard Earth's model, and the topographic effects around the sites. Using the site effects, coseismic strain steps observed by the strainmeter network are compared with fault parameters estimated from seismic observations and the detectability of the fault mechanisms using the strainmeter network is estimated. For long-term strain changes, local disturbances of the sites and detectability of the network are estimated using GNSS data. In the presentation, we discuss detectability of the strainmeter network for seismic and geodetic signals and prospects for monitoring crustal activities using long-baseline laser strainmeters.
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