HR: 0800h
AN: H11D-0330    [Abstracts]
TI: Using Earthquake and Seasonal Variation of Precipitation to Characterize the Aquitard Properties of the Choshuishi Alluvial Fan, Taiwan
AU: Wang, S
EM: n4891110@ccmail.ncku.edu.tw
AF: Department of Resources Engineering, National Cheng-Kung University, Department of Resources Engineering, National Cheng-Kung University, Tainan, 701 Taiwan
AU: Hsu, L
EM: nett@mail2000.com.tw
AF: Department of Resources Engineering, National Cheng-Kung University, Department of Resources Engineering, National Cheng-Kung University, Tainan, 701 Taiwan
AU: Lai, W
EM: laiwenji@dprc.ncku.edu.tw
AF: Department of Resources Engineering, National Cheng-Kung University, Department of Resources Engineering, National Cheng-Kung University, Tainan, 701 Taiwan
AU: * Hsu, K
EM: kchsu@mail.ncku.edu.tw
AF: Department of Resources Engineering, National Cheng-Kung University, Department of Resources Engineering, National Cheng-Kung University, Tainan, 701 Taiwan
AU: Wang, C
EM: clwang@mail.ncku.edu.tw
AF: Department of Resources Engineering, National Cheng-Kung University, Department of Resources Engineering, National Cheng-Kung University, Tainan, 701 Taiwan
AB: Characterizing the subsurface system is important to understand the processes of groundwater flow, solute transport or earthquake mechanism. The Choshuishi Alluvial Fan is one of the most important groundwater resources in Taiwan. The aquifers are mainly composed of gravel and coarse sand and are separated by aquitards of clay and silt. The existing monitoring system composing of 188 monitoring wells at 73 stations mainly provides hydrogeological information of aquifer for the purpose of water resources management. However, the properties of aquitards are required to construct a fully three dimensional hydrogeoloical model. Natural excitations such as earthquake, rainfall or atmospheric pressure change is useful to characterize the properties of aquitard. The post-seismic groundwater fluctuation of Chi-Chi earthquake with Mw 7.6 happened in 1999 is used to obtain the diffusivity of aquitard. Long-term record of groudwater level fluctuation is analyzed by harmonic analysis to obtain the vertical hydraulic conductivity. With the obtained aquitard properties, the hydrogeology of the Choshuishi Alluvial Fan becomes more lucid.
DE: 1829 Groundwater hydrology
DE: 1854 Precipitation (3354)
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting