Fig. 8

Tracing of 10,000 fluid particles through one realisation of Model A. A Travel time of particles from lower to upper model boundary as a function of coordinates along the X axis. 50% particles exit the upper boundary between 1.2 and 1.7 days, and through fractures located between X = 503 m and X = 537 m. “golden fracture”: fracture through which 10% of the tracing particles exit. Time axis is in logarithmic scale. B Location of fractures through which particles exit the model, and other fractures from backbone network crossing the upper boundary (Y = 1000). The particles leave the upper boundary through 92 fractures spread over 287 m. In this interval, 71 fractures do not host exiting fluid particles. In all, 550 fractures intersect the upper boundary of the model domain. C Paths taken by fluid particles which enter the model domain through a single fracture on the lower boundary