Analysis of Groundwater Level Changes and Tectonic Strain Induced by Fault Movement (II)

The pore water pressure and volumetric strain of geologic formation could be changed by tectonic stress redistribution resulting from fault movement. During the occurrence of Chi-Chi earthquake, 157 monitoring wells in the footwall of Chelungpu fault recorded water level changes, inspiring the study of relations between groundwater level changes and tectonic strain due to the fault movement. This project intends to establish a conceptual model, develop a mathematical model and a finite-element model to evaluate the transient processes of groundwater level changes and tectonic strain due to fault movement under various geologic conditions and physical parameters. The theoretical study results will be compared and validated by the observed spatial and temporal distribution of groundwater level changes and horizontal displacement induced by the Chi-Chi earthquake. Results of this study are anticipated to enhance our understanding of major factors controlling the coupled process of groundwater level changes and volumetric strain due to fault movement. Furthermore, the project will cooperate with the United States and France in the research of static and dynamic processes of coseismic groundwater level changes