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Yingdi LUO02/15/2012Ge169/277

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Chang et al. 2009 Chihshang Fault: 35km long Reverse fault 20-30 mm/yr Chihshang Fault: 35km long Reverse fault 20-30 mm/yr 2003 Chengkung EQ.

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Chang et al. 2009 Well A Average Well B 15mm/yr 2003 Chengkung EQ. 5X creep rate

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Well A Average ground water level Average ground water level Well B Water table (estimated) Chang et al. 2009 De-trended shortening Rainfall 50 day lag: Rising water table Increased Rainfall 50 day lag: Rising water table Increased Rainfall

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Saar & Manga 2003 Stream discharge gauging station Stream discharge gauging station Summit Mt. Hood Seismometers Earthquakes

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Saar & Manga 2003

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Cumulative mean daily stream discharge Cumulative mean daily stream discharge Cumulative number of earthquakes Cumulative seismic moment Cumulative seismic moment

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Saar & Manga 2003 Cumulative mean daily stream discharge Cumulative mean daily stream discharge Cumulative number of earthquakes Cumulative seismic moment Cumulative seismic moment

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Saar & Manga 2003 Interpolated Time Series Time lag: 151 days

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Saar & Manga 2003

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Periodic pore-fluid pressure variation 1D half-space diffusion equation Hydraulic diffusivity Solution

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Saar & Manga 2003 Periodic pore-fluid pressure variation 1D half-space diffusion equation Hydraulic diffusivity Solution Permeability Hydraulic conductivity Hydraulic diffusivity

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Periodic pore-fluid pressure variation 1D half-space diffusion equation Hydraulic diffusivity Solution Chang et al. 2009 Hydraulic diffusivity t ~ 50day, z ~ 30m => ~ 1.2e-4 m 2 /s

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Periodic pore-fluid pressure variation 1D half-space diffusion equation Hydraulic diffusivity Solution Chang et al. 2009 Rate-strengthening friction

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Chang et al. 2009

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Hydraulic diffusivity = 0.05m 2 /s

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Christiansen et al. 2007

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Chang, S.H., Wang, W.H. & Lee, J.C., 2009. Modeling temporal variation of surface creep on the Chihshang fault in eastern Taiwan with velocity- strengthening friction, Geophysical Journal International, 176, 601-613. Christiansen, L.B., Hurwitz, S. & Ingebritsen, S.E., 2007. Annual modulation of seismicity along the San Andreas Fault near Parkfield, CA, Geophysical Research Letters, 34. Saar, M.O. & Manga, M., 2003. Seismicity induced by seasonal groundwater recharge at Mt. Hood, Oregon, Earth and Planetary Science Letters, 214, 605-618.