Author(s)

Shigeru Toda, Hiroki Miyamachi, Hiroshi Murakami, Tomoki Tsutsui, Masaki Kanao

Department of Earth and Environmental Sciences, Faculty of Science, Kagoshima University, Kagoshima, Japan.
Department of Earth Sciences, Faculty of Education, Aichi University of Education, Kariya, Japan.
Faculty of Engineering and Resource Science, Akita University, Akita, Japan.
National Institute of Polar Research, Tokyo, Japan.
Technical Center for Seismological Observations Ltd., Tsukuba, Japan.

A gravity survey was conducted along the Mizuho traverse routes in austral summer of 1999-2000 by the 41^st Japanese Antarctic Research Expedition (JARE-41). The main purpose of the survey was to obtain detail gravity anomaly along the traverse routes, where deep seismic exploration was simultaneously conducted in order to obtain a fine crustal structure of the Mizuho Plateau. By using SCINTREX (CG-3M) gravity meter, the survey was carried out at 160 sites with about 1 km interval in a distance of 190 km from S16 to Z20 on the traverse routes. Free-air and Bouguer anomalies were calculated using precise locations by GPS measurements, by taking into account an effect of the thick icesheet. The furrowed negative Free-air anomalies are identified around H192, where middle points of the whole traverse routes. Two bedrock elevation models derived both by seismic refraction analyses and radio-echo sounding might correspond to the bottom and the top of a mixture layer composed from ice-moraine rocks over the bedrock surface. Thickness of the crust estimated by Bouguer anomalies is 0.5 - 1 km larger toward inland at the terminal point of Z20 along the profile.

Gravity Survey; Mizuho Traverse Routes; Bedrock Elevation; Bouguer Gravity Anomaly; Crustal Structure

S. Toda, H. Miyamachi, H. Murakami, T. Tsutsui and M. Kanao, "Gravity Survey along the Mizuho Traverse Routes, East Antarctica: SEAL Seismic Exploration in 1999-2000," International Journal of Geosciences, Vol. 4 No. 10, 2013, pp. 1392-1400. doi: 10.4236/ijg.2013.410136.