Open AccessSpatial Distribution of Groundwater Level Changes Induced by the 2006 Hengchun Earthquake Doublet
Author(s) -
Yeeping Chia,
Jeng Jiann Chiu,
Po-Yu Chung,
Y. Chang,
Wen Liang Lai,
Y. Kuan
Publication year - 2009
Publication title -
terrestrial, atmospheric and oceanic sciences/terrestrial, atmospheric, and oceanic sciences
Language(s) - English
Resource type - Journals
eISSN - 2223-8964
pISSN - 1017-0839
DOI - 10.3319/tao.2008.01.10.01(tt
Subject(s) - groundwater , spatial distribution , distribution (mathematics) , geology , seismology , environmental science , remote sensing , geotechnical engineering , mathematics , mathematical analysis
Water-level changes were ob served in 107 wells at 67 monitoring stations in the southern coastal plain of Tai wan during the 2006 Mw 7.1 Hengchun earthquake doublet. Two consecutive coseismic changes induced by the earth quake doublet can be observed from high-frequency data. Obervations from multiple-well stations indicate that the magnitude and direction of coseismic change may vary in wells of different depths. Coseismic rises were dominant on the south east side of the costal plain; whereas, coseismic falls prevailed on the north west side. In the transition zone, rises appeared in shallow wells whilst falls were evident in deep wells. As coseismic ground water level changes can reflect the tectonic strain field, tectonic extension likely dominates the deep subsurface in the transition area, and possibly in the en tire southern coastal plain. The coseismic rises in water level showed a tendency to de crease with distance from the hypocenter, but no clear trend was found for the coseismic falls