HR: 0800h
AN: H11D-0323 INVITED     [Abstracts]
TI: The Relationship Between Groundwater Monitoring Networks and the Chi-Chi Earthquake in Taiwan
AU: * Tan, Y
EM: yctan@ntu.edu.tw
AF: National Taiwan University, 1, Sec. 4, Roosevelt Road, Taipei, 106 Taiwan
AB: A visco-elastic model is developed to simulate the ground water level changes in the Cho-Shui River alluvial fan in Taiwan after the Chi-Chi earthquake with magnitude 7.3 on the Richter scale. In addition, an analytical solution is derived with the assumption that no leakage occurred in confined aquifers during the co-seismic period. The solution is used to analyze the data collected from a high-density network of Groundwater monitoring wells in the Cho-Shui River alluvial fan. The simulated ground water level changes agree with the observations. The viscosity coefficient of the model was found to correlate with the hydraulic conductivity of the aquifer. The field observations and the simulations reveal the influence of geological structures and heterogeneity on the ground water changes and locations of sediment liquefactions in the alluvial fan during the Chi-Chi earthquake. Possible applications to imaging subsurface hydraulic heterogeneity are discussed using information about ground water level changes induced by earthquakes. Keywords­GChi-Chi earthquake, Groundwater level changes in wells, Visco-elastic model, Delineation, Sand/gravel formation.
DE: 5114 Permeability and porosity
DE: 7209 Earthquake dynamics and mechanics
DE: 1829 Groundwater hydrology
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting