Changes

===Structural deformation===

===Structural deformation===

[[Deformation|Fracturing and brecciation associated with folds, faults, and diapirs]] generally increase the reservoir quality of well-indurated rocks (see [[Evaluating fractured reservoirs]]). [[Fracture]] porosity is typically low, usually providing only about 1% porosity; however, fractures in large reservoirs may hold considerable reserves. Fracture permeability may be as high as tens of darcies and is directional in nature. Conversely, fractures filled by mineralization or with gouge may produce a permeability barrier in the direction perpendicular to the fracture. Brecciation along fracture or fault zones may occur due to shearing or dissolution and collapse. Except where mineralization has occurred in the breccia, brecciation can increase both porosity and permeability considerably. Closely spaced sealing faults can significantly compartmentalize a reservoir.

[[Fracture|Fracturing]] and [[breccia]]tion associated with folds, faults, and [[diapirs]] generally increase the reservoir quality of well-indurated rocks (see [[Evaluating fractured reservoirs]]). [[Fracture]] porosity is typically low, usually providing only about 1% porosity; however, fractures in large reservoirs may hold considerable reserves. Fracture permeability may be as high as tens of darcies and is directional in nature. Conversely, fractures filled by mineralization or with gouge may produce a permeability barrier in the direction perpendicular to the fracture. Brecciation along fracture or fault zones may occur due to shearing or dissolution and collapse. Except where mineralization has occurred in the breccia, brecciation can increase both porosity and permeability considerably. Closely spaced sealing faults can significantly compartmentalize a reservoir.

===Wettability===

===Wettability===