DOI: 10.3724/SP.J.1085.2013.00339

Advances in Polar Science 2013/24:4 PP.339-343

Field measurements of absolute gravity in East Antarctica

This paper reports the results of field-based absolute gravity measurements aimed at detecting gravity change and crustal displacement caused by glacial isostatic adjustment.The project was initiated within the framework of the 53rd Japanese Antarctic Research Expedition(JARE53).Absolute gravity measurements,together with GPS measurements,were planned at several outcrops along the Prince Olav Coast and Sôya Coast of East Antarctica,including at Syowa Station.Since the icebreaker Shirase(AGB 5003)was unable to moor alongside Syowa Station,operations were somewhat restricted during JARE53.However,despite this setback,we were able to complete measurements at two sites:Syowa Station and Langhovde.The absolute gravity value at the Syowa Station IAGBN(A)site,observed using an FG-5 absolute gravimeter(serial number 210;FG-5#210),was982 524 322.7±0.1μGal,and the gravity change rate at the beginning of 2012 was-0.26μGal·a-1.An absolute gravity value of 982535 584.2±0.7μGal was obtained using a portable A-10 absolute gravimeter(serial number 017;A-10#017)at the newly located site AGS01 in Langhovde.

Key words:absolute gravity,field measurement,Antarctica,A-10 and FG-5 absolute gravimeters,GPS,JARE

ReleaseDate:2015-04-16 13:27:19

1 Wahr J, Da Zhon H, Trupin A. Predictions of vertical uplift caused by changing polar ice volumes on a viscoelastic earth. Geophys Res Lett, 1995, 22(8): 977-980.

2 Nakada M, Okuno J. Temporal gravity change and crustal movement induced by glacial rebound: method to estimate recent mass balance of Antarctic and Greenland ice sheets. Mizusawa, Joint symposium: New era of satellite gravity mission and satellite altimetry//National Astronomical Observatory of Japan, 2001 (in Japanese with English abstract).

3 Mäkinen J, Amalvict M, Shibuya K, et al. Absolute gravimetry in Antarctica: Status and prospects. J Geophys, 2007, 43(3): 339-357, doi:10.1016/ j.jog.2006.08.002.

4 Sugawara Y. Gravity measurements with the portable absolute gravimeter FG-5 at Antarctica (W). Kokudo Chiriin Jihou, 2012, 121: 9-19 (in Japanese).

5 Fukuda Y, Higashi T, Takemoto S, et al. Absolute gravity measurements in Australia and Syowa Station, Antarctica, IAG Symposia 129//Jekeli C, Bastos L, Fernandes J. Gravity, geoid and space missions. New York: Springer, 2005: 280-285.

6 Micro-G LaCoste. A10 portable gravimeter user's manual. http://, 2008.

7 Wessel P, Smith W H F. New, improved version of Generic Mapping Tools released. EOS Trans AGU, 1998, 79(47): 579.

8 Ueda J. Preliminary survey report on estimation of displacement rate due to post glacial rebound by absolute gravity measurement and GPS measurement in the coastal region of Antarctica (AP18)//Tokyo: Japan Association of Surveyors, 2011 (in Japanese).

9 Kazama T, Hayakawa H, Higashi T, et al. Gravity measurements with a portable absolute gravimeter A10 in Syowa Station and Langhovde, East Antarctica. Polar Science, 2013, 7(3-4): 260-277.

10 Higashi T, Doi K, Hayakawa H, et al. Gravity measurements using absolute gravimeter FG5 and secular gravity changes at Syowa Station, Antarctica. J Geod Soc Japan, 2013, 59(2): 37-43 (in Japanese).

11 Ekman M, Makinen J. Recent postglacial rebound, gravity change and mantle flow in Fennoscandia. Geophys J Int, 1996, 126(1): 229-234.

12 Ohzono M T, Tabei K, Doi K, et al. Crustal movement of Antarctica and Syowa Station based on GPS measurements. Earth Planets Space, 2006, 58: 795-804.