[S-SS05] Advancements in Regional Seismic Networks: Operations, Applications, and Development

[SSS05-06] Seismic Deployment over the Antarctic Continent during the International Polar Year (IPY2007-2008) : POLENET & AGAP/GAMSEIS

*Masaki Kanao¹, Seiji Tsuboi², Genti Toyokuni³ (1.National Institute of Polar Research, 2.JAMSTEC, 3.Tohoku University)

Keywords:Antarctic continent, International Polar Year, POLENET, AGAP/GAMSEIS, Gambursev Sub-Glacial Mountains

During the last International Polar Year (IPY) campaign in 2007-2008, the Antarctica GAmburtsev Province / GAmburtsev Mountain SEISmic experiment (AGAP/GAMSEIS) was an internationally coordinated deployment by serving broadband seismic stations over the high altitude ice plateau area (Gambursev Mountains (Dome-A) - Dome-F) in East Antarctica. Two remote stations (GM06, GM07 (Dome-F)) were newly established by Japanese initiatives. The GAMSEIS deployment gave constraints on the origin of Gamburtsev Sub-Glacial Mountains with broad structure and evolution of East Antarctic craton and subglacial environment. The detection of seismic signals from phenomenon at the base of the ice sheet, such as outburst floods from subglacial lakes were expected from detailed analyses. The AGAP initiative during IPY2007-2008 was a unique opportunity for implementing the global network (GSN), as well as serving as a part of the geophysical observing network covering the whole area of Antarctic continent (the POLENET). From the GAMSEIS data, local signals involving ice sheet and atmosphere variations were recorded, with a significant number of teleseismic events. Moreover, field observations by using portable broadband seismometers have been carried out at several outcrops around the coast of the Lützow-Holm Bay region, East Antarctica since 1996 by Japanese initiative. These local array observations have also been conducted in cooperation with the Global Alliance of Regional Networks (GARNET), Antarctic international programs at the IPY (AGAP, POLENET, SERCE, etc.). The recorded data are of enough quality to be used for various waveform analyses to clarify the heterogeneous structure of the Antarctic Plate and surrounding areas. In this presentation, a general overview of these IPY projects and scientific achievements are demonstrated, focusing on the obtained precise structure of the crust and upper mantle of the region.