Abstract:

Precise geodetic observations with VLBI, GPS and DORIS have been carried out at Syowa Station (69.0degS, 39.6 degE), Antarctica. Crustal uplift rates of 4.6 +- 2.2 mm/yr (VLBI), 2.3 +- 0.3 mm/yr (GPS) and 3.6 +- 0.2 mm/yr (DORIS) gave consistent estimates with each other. Regional GPS campaigns (1998-2004) in the 100-km-long SW-NE trending bedrock areas gave the uplift rates of 1.1-4.5 mm/yr. Repeated AG measurements with an FG5 three times during 1994-2004 showed the gravity decrease rate of -0.3 +- 0.4 microGal/yr, which has consistent tendency with the value by kinematics. We archived 10 years' SG observations (1993-2003) and obtained tidal gravimetric factors to an accuracy within 0.1% for the periods from 0.5 to 32 days. Comparison of GRACE-derived monthly gravity fields with SG non-tidal variations are underway. We also archived >20,000 SAR (JERS-1, ERS-1, ERS-2) scenes during 1992-2004 received by the Syowa S/X-band antenna, and delineated the grounding lines of the East Antarctic coastal zones (25degW to 40degE) from InSAR analyses to update the ADD coastlines. Two OBPs were installed to the north of Syowa Station (2004.12 - 2006.02, 66.9degS and 37.8degE) and the one picked up after 50 days recorded the tsunami induced by the Sumatera Earthquake of December, 2004. In the austral summer season 2005-2006, airborne geophysical survey flights over the area of 64S-74S by 36E-48E, will be conducted in cooperation with the AWI, Germany.