High strain rate loading causes pervasive dynamic microfracturing in crystalline materials,
with dynamic pulverization being the extreme end-member. Hydraulic properties (permeability,
porosity, and storage capacity) are primarily controlled by fracture damage and will therefore change
significantly by intense dynamic fracturing—by how much is currently unknown. Dynamic fracture
damage observed in the damage zones of seismic faults is thought to originate from dynamic stresses near
the earthquake rupture tip. This implies that during an earthquake, hydraulic properties in the damage
zone change early. The immediate effect this has on fluid-driven coseismic slip processes following the
rupture, and on postseismic and interseismic fault zone processes, is not yet clear. Here, we present
hydraulic properties measured on the full range of dynamic fracture damage up to dynamic pulverization.
Dynamic damage was induced in quartz-monzonite samples by performing uniaxial high strain rate
(> 100 s−1) experiments in compression using a split-Hopkinson pressure bar. Hydraulic properties were
measured on samples subjected to single and successive loadings, the latter to simulate cumulative damage
from repeated rupture events. We show that permeability increases by 6 orders of magnitude and porosity
by 15% with dissipated energy up to dynamic pulverization, for both single and successive loadings. We
present damage zone permeability profiles induced by earthquake rupture and how it evolves with
repeated ruptures. We propose that the enhanced hydraulic properties measured for pulverized rock
decrease the efficiency of thermal pressurization, when emplaced adjacent to the principal slip zone
