摘要：Abstract
The integrated evaluation of borecores from the
Mezősas-Furta fractured metamorphic hydrocarbon reservoir
suggests significantly distinct microstructural and
rock mechanical features within the analysed fault rock
samples. The statistical evaluation of the clast geometries
revealed the dominantly cataclastic nature of the samples.
Damage zone of the fault can be characterised by
an extremely brittle nature and low uniaxial compressive
strength, coupled with a predominately coarse fault breccia
composition. In contrast, the microstructural manner
of the increasing deformation coupled with higher uniaxial
compressive strength, strain-hardening nature and
low brittleness indicate a transitional interval between
the weakly fragmented damage zone and strongly grinded
fault core. Moreover, these attributes suggest this unit is
mechanically the strongest part of the fault zone. Gougerich
cataclasites mark the core zone of the fault, with their
widespread plastic nature and locally pseudo-ductile microstructure.
Strain localization tends to be strongly linked
with the existence of fault gouge ribbons. The fault zone
with ∼15 m total thickness can be defined as a significant
migration pathway inside the fractured crystalline reservoir.
Moreover, as a consequence of the distributed nature
of the fault core, it may possibly have a key role in compartmentalisation
of the local hydraulic system.
