Category: Transient Plane Source
Abstract: The frictional heat produced by the 1999 Chi-Chi, Taiwan earthquake was estimated by identifying a temperature anomaly that is present in a borehole drilled through a large slip region of the fault. The temperature rise was estimated by solving an equation representing one-dimensional thermal conduction in an infinite medium. In order to solve this equation, the thermal diffusivity of fracture zone materials were measured using the transient plane source technique. It was also necessary to measure the specific heat and density of these materials. The dynamic shear stress was estimated to be 0.5 to 0.9 MPa, and the estimated heat produced was 0.68 to 1.32 x 1017 J. The total frictional energy produced by faulting was estimated to be 2.4 x 1017 J.
Reference: Geophysical Research Letters, 33, 16 (2006)