3D Pore-network quantitative analysis in deformed carbonate grainstones

On the basis of the obtained results, inferences about the control of pore network properties on permeability were made for both host rock and deformation bands. In the host rocks, high values of connectivity seem to be associated with high values of permeability, whereas higher values of the specific surface area seem to correspond to lower permeability. Within the deformation bands, both porosity and pore connectivity are reduced except for local solution-enlarged stylolites and fractures (slip surfaces) preferentially connected parallel to the deformations bands.
The morphology and distribution of connected pores may have an impact on the permeability may explain variability on their permeability reported for the studied rocks.
In the fault zones, both connected porosity and pore connectivity decrease drastically due to the collapse or occlusion of pores by compaction, cataclasis or cementation. Therefore, the cemented and the cataclastic zones could be considered as local buffer zones or barriers to fluid flow. On the contrary, the connected pore-network, made of solution-enlarged stylolites and slip surfaces, is preferably connected and distributed parallel to the fault. Therefore, this configuration of conduits and local barriers may cause an anisotropy in the permeability within the fault zone.

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