https://repository.kopri.re.kr/handle/201206/5520 2026-04-17T03:33:38Z https://repository.kopri.re.kr/handle/201206/6575 Title: Detection of long period seismic events by using a portable gravity meter, gPhone Authors: Lee, Won Sang; Yoo, Hyun Jae; Yun, Sukyoung; Park, Yongcheol; Lee, Choon-Ki; Shin, Dong-Hoon; Eom, Jooyoung; Seo, Ki-Weon Abstract: A gravity meter has been used for exploring subsurface mineral resources and monitoring long-period events such as Earth tides. Recently, researchers found several other intriguing features that we could even detect large teleseismic earthquakes and monitor seismic ambient noise using gravimeters. The zero-length spring suspension technology gives the gPhone (Micro-g LaCoste) excellent low frequency sensitivity, which may have implications for investigating much longer-period natural events (e.g., Earth's hum, tsunami waves, etc.). In this study, we present preliminary results through temporary operation of the gPhone at Geumsan in South Korea for 9 months (Nov. 2008-Jul. 2009). The gPhone successfully recorded large teleseismic events and showed a clear seasonal variation of the Double frequency microseisms during its operation period. 2015-01-01T00:00:00Z https://repository.kopri.re.kr/handle/201206/9021 Title: Improvement of oceanic T-wave excitation modeling method and its application Authors: Lee, Won Sang 2015-01-01T00:00:00Z https://repository.kopri.re.kr/handle/201206/6574 Title: Hydroacoustic Observation on the 2011 Tohoku Earthquake Authors: Lee, Won Sang; Yun, Sukyoung Abstract: The MW 9.0 thrust-fault earthquake has occurred in the Pacific coast of Tohoku, Japan, on March 11, 2011. We present the detection of the great earthquake and analyze T-waves associated with the main event and two other big aftershocks (MW > 7) recorded in a hydroacoustic array (H11N) in the Pacific Ocean by performing array and spectral analysis to examine characteristics of T-waves generated from the big events. The complex rupture process of the main event directly influences on the shape of the T-waves, and the peak locates on where T-waves excited from fast rupturing process arrive. We compare the two aftershocks with different fault type and show that the fault type and the source depth change shape and spectral contents of T-waves. 2013-01-01T00:00:00Z https://repository.kopri.re.kr/handle/201206/8098 Title: Engineering Seismology, Geotechnical and Structural Earthquake Engineering (Seismic ambient noise and its applicability to monitor cryospheric environment) Authors: Lee, Joohan; Lee, Won Sang; 한신애 2013-01-01T00:00:00Z