TITLE:
Observation and Data Archiving System of a Superconducting Gravimeter at Syowa Station, Antarctica
AUTHORS:
Yuichi Aoyama, Hiroshi Ikeda, Hideaki Hayakawa, Koichiro Doi, Yoichi Fukuda, Kazuo Shibuya
KEYWORDS:
Superconducting Gravimeter, Remote Observation Monitoring, High Quality Data, Antarctica
JOURNAL NAME:
International Journal of Geosciences,
Vol.6 No.10,
October
28,
2015
ABSTRACT: A superconducting
gravimeter (SG, model TT70#016, GWR Instruments) was deployed for the first
time in Antarctica in 1992 at Syowa Station. Observations began in April 1993.
Although the SG was equipped with a 10 K cryocooler, its liquid helium (LHe)
required refilling twice a year to maintain its superconducting state. The LHe
was produced by a separate helium liquefier. After continuous gravity
measurement with the SG for 11 years, it was replaced by a second SG (CT#043) with
a 4 K cryocooler in December 2003 in order to reduce loads of person in charge
for LHe production. Because the manufacturer could not supply a replacement 4 K
cryocooler, this SG ceased measurement in November 2009. In January 2010, a new
superconducting gravimeter (OSG#058) was installed and had recorded
high-quality gravity time series with data acquired every second for more than
five years without interruption. Because the personal computer (PC) controlling
the observation and data acquisition is connected with PCs in Japan through an
Intelsat satellite communication link, we can check the status of observations
in real time. It is also possible to fix remotely certain problems with the
gravimeter. The observed gravity data are transferred daily to a data server in
Japan. Also included in the upload are diagnostic data of the gravimeter such
as the temperature of the coldhead and environmental data such as atmospheric
pressure. Plots of the daily data are publicly available. The raw data with a 1
s sampling interval are also released to registered researchers. The released
gravity time series along with the environmental data are greatly useful for
investigating solid earth dynamics especially in the long period bands. We
provide necessary information to use these long-range data sets.