  Numerical simulations of vein evolution contribute to a better understanding
of processes involved in their formation and possess the potential to provide
invaluable insights into the rock deformation history and fluid flow pathways.
The primary aim of the present article is to investigate the influence of a
realistic boundary condition, i.e. an algorithmically generated fractal
surface, on the vein evolution in 3-D using a thermodynamically consistent
approach, while explaining the benefits of accounting for an extra
dimensionality. The 3-D simulation results are supplemented by innovative
numerical post-processing and advanced visualization techniques. The new
methodologies to measure the tracking efficiency demonstrate the importance of
accounting the temporal evolution; no such information is usually accessible in
field studies and notoriously difficult to obtain from laboratory experiments
as well. The grain growth statistics obtained by numerically post-processing
the 3-D computational microstructures explain the pinning mechanism which leads
to arrest of grain boundaries/multi-junctions by crack peaks, thereby,
enhancing the tracking behavior.
