Development of laser interferometer strain-seismometer

2005 Fiscal Year Final Research Report Summary

• Project/Area Number: 15340148
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Solid earth and planetary physics
• Research Institution: Nagoya University
• Principal Investigator: YAMADA Isao Nagoya University, Graduate school of environmental studies, Prof., 大学院・環境学研究科, 教授 (60022670)
• Co-Investigator(Kenkyū-buntansha): FUKAO Yoshio Japan agency for marine-earth science and technology, Director of IFREE, 地球内部センター, センター長 (10022708) ; ARAYA Akito Tokyo University, Institute of Earthquake, Associate Prof., 地震研究所, 助教授 (30272503)
• Project Period (FY): 2003 – 2005
• Keywords: seismometer / laser interferometer / strain seismometer / broad-band seismometer

Research Abstract

We developed the strain-seismometer which used a laser interferometer in this project. This year, we did observation with this super long period seismometer and did comparison with a record of quartz pipe strain meter and STS -1 type broad-band seismometer.
As a result it does not extend to performance of a STS -1 type seismometer.
We can get a good record by revising atmospheric pressure and a change of minute temperature in an observation trench. The cause of noise is understood that it was warp of the laser interferometer by around 1/100 deg.temperature change in a trench by observation of temperature by an exact thermometer and observation of atmospheric pressure change by a micro-barometer.
The developed strain seismometer seems to do warp by temperature more greatly, because various kinds of materials are used every a part by difficulty and a price of production. I have to build the system which is not influenced in a temperature change by materials of super iron-nickel alloy with a little temperature changes.