Research Article

Fault “Corrosion” by Fluid Injection: A Potential Cause of the November 2017 5.5 Korean Earthquake

Figure 13

Timescales for equilibration of concentration of dissolved silica (i.e., Si(OH)4) in fractures of width (where , 0.6, and 6 mm), after Rimstidt and Barnes [68]. Calculations assume Si(OH)4 concentrations of zero, initially, increasing to 99.3% of the equilibrium value, thus depicting five times the “time constant” for the dissolution. Box represents a temperature and a 2-3 month timescale, consistent with the bottom-hole temperature and postinjection time-delay observed at Pohang in 2017.