17:15 〜 19:15
[MTT36-P01] Cryoseismology studies for monitoring surface environment in polar regions – A decade progress around the Lützow-Holm Bay region, East Antarctica -
キーワード：雪氷圏地震学、東南極、リュツォ・ホルム湾地域、共振微動、インフラサウンド
Majority areas of Antarctica and Greenland are covered by the thick ice sheet and characterized by the evolving cryosphere in the surfce environment. In polar regions, associated with recent trend on climate change such as global warming, glacier relating earthquakes are increasing during 21st century, especially in Greenland. In this presentation, a decade of progress in “Cryoseismology” in East Antarctica, particularly in the Lützow-Holm Bay (LHB) region, is reviewed by focusing on major scientific achievements from seismic and infrasound investigations. For exmaple, specific cryoseismic events are demonstrated, which occurred in the coastal area of the LHB. Frequency-overtone seismic signals in harmonic tremors were recorded explained by assuming constant-durating sources, suggesting inter-glacial asperities that generate characteristic tremors. Moreover, the harmonic tremors in April 2015 were identified to be involved in discharge events of a large volume of sea-ice, linking with collision events between icebergs which had drifted from eastward offshore of the Enderby Land (Tanaka et al., 2019). In contrast, infrasound generating sources’ locations and propagation directions were also determined by using a couple of array deployment in LHB. Time-space variations of the infrasound source locations in 2019-2021 were recently studied by a combination of two local arrays deployed at coastal outcrops of the region. Seasonal variations were clearly identified in frequency contents of the signals as well as propagating directions during the three years (Kanao et al., 2024). These scientific findings could give a new insight into the understanding of multi-sphere dynamics among cryosphere, atmoephere, ocean and solid earth in the Antarctic.