Enargy taken up by co-seismic chemical reactions during a large earthquake : An example from the 1999 Taiwan Chi-Chi earth quake

Frictional heat in a fault zone during earthquake slip transiently induces chemical reactions that may use energy released during the earthquake. We estimated the energy used by such reactions (EC) by a numerical analysis incorporating frictional heat, thermal diffusion, chemical kinetics, and energy conservation, and found that EC has an auto-feedback effect that inhibits temperature rise in fault zone. During the 1999 Taiwan Chi-Chi earthquake, estimated EC was 0.43 MJ/m2, corresponding to 0.79% of the frictional heat generated. This low percentage probably reflects the low initial concentrations of reactive materials. However, in the case of a fault with abundant reactive materials, EC could reach >50% of the frictional heat and the auto-feedback effect could be large. At this case EC is a non-negligible component on earthquake energy budget and can affect fault mechanics.