Fig. 4

Estimation of water flows around microseismic clusters. a, b Variation in elastic wave velocity in rock fractures in a Phase 2 and b Phase 3 compared to the velocity in Phase 1. Velocity variation is shown by the color of each circle. Each circle is at the hypocenter of the analyzed earthquakes. c, d Cross sections of the fractures and distributions of microseismic events along the blue dashed line in the horizontal map. Results for c Mqs1 and 2 and d Mqs3. The color scales at the top of c and d indicate the probability that a fracture exists