11:15 AM - 11:30 AM
[SGD02-09] Development of a new portable gravity gradiometer for field measurements
The first prototype of the gravity gradiometer was tentatively operated at the Sakurajima Volcanological Observatory of Kyoto University, located on the active volcanic island of Sakurajima, Kyusyu Japan. From this tentative operation, it was found that the instrument was robust against seismic vibration; the resolution was ±0.3μGal/m, which is the same level as that operated at a quiet observation station. This result indicates that this gravity gradiometer could detect local underground activities, which are buried in seismic noise and have not been detected by previous gravimeters. However, the first prototype is heavy (weighs about 200 kg) and it was difficult to install it at the local observatory without crane equipment. We are developing a new laser-interferometric gravity-gradiometer that is designed to be portable and more practical for field measurements. In this presentation, I will report the status and prospects of the development.
 S. Shiomi et al. (2012): Development of a Laser-interferometric Gravity-gradiometer, Journal of Geodetic Society of Japan Vol. 58, No.4, pp. 131-139.
 S. Shiomi (2002): Test mass metrology for tests of the Equivalence Principle, Ph.D. thesis, The University of Birmingham, Edgbaston, Birmingham, UK.