4:45 PM - 5:00 PM
[SGD02-12] Design and operation of a 1.5-km laser strainmeter installed in the KAGRA underground site (III)
Keywords:strainmeter, laser, crustal deformation, KAGRA, Kamioka
In 2016, a new laser strainmeter with a 1.5-km baseline was constructed at an underground site and started test observation. The site is a part of KAGRA gravitational wave detector [3, 4] in Kamioka. The strainmeter clearly detected earth tides with a slight amplitude reduction due to the topographic effect, seismic waves from local and distant earthquakes , and coseismic strain steps associated with generation of seismic faults by earthquakes .
For long-term strain changes, 1.5-km data showed smaller strain changes than that of existing 100-m laser strainmeter , however more data are needed to draw a definitive conclusion. In the presentation, we discuss detectability of the 1.5-km laser strainmeter especially for long-term strain changes and prospect for monitoring crustal dynamics using the long-baseline strainmeter.
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