Seismic Survey for the Subglacial Lake in Antarctica

초록

The Korea Polar Research Institute (KOPRI) conducted Korea's first seismic survey of an Antarctic glacier to investigate the size and subsurface structure of subglacial lake D2 beneath the David Glacier. The initial seismic survey was conducted during the 2019-2020 Antarctic summer season, utilizing infrastructure from the Jang Bogo Station and the Korean inland route (K-Route). This survey confirmed the existence of a subglacial lake and provided comprehensive data for preliminary structural analysis. Based on these findings, a second seismic survey was conducted during the summer of 2021-2022. In this survey, we employed a methodology to address the environmental challenges of the Antarctic inland ice sheet and to enhance detection resolution for subglacial lake sedimentary structures. In the second survey, the explosive charge was increased from 400 g to 1,600 g, the number of rod-type receiver channels was expanded from 48 to 96 channels, and the fold number was increased from 1 to 4 or 8, improving data quality and clarity. In addition, 25-30 m hot-water drilling was used to position explosives within the boreholes, which were then allowed to freeze solidly to maximize energy transmission efficiency. These high-quality seismic data enabled precise delineation of the subglacial lake's size, structural features, and underlying sedimentary layers, thereby providing critical information for selecting optimal sites for further hot-water drilling. This dataset establishes foundational resources for Antarctic subglacial lake research and will support future studies on subglacial lake dynamics and structural analyses across Antarctica.

키워드