There are 2 basic types of natural fractures that need to be studied when characterising naturally fractured reservoirs - whether it be a geothermal or hydrocarbon reservoir. These are extension and shear fractures.
Deformation bands are fault-like structures that reduce the reservoir quality of otherwise good quality sandstones. Here we look at their impact upon effective permeability, which has implications during reservoir development.
Deformation bands can compartmentalise reservoirs, causing challenges for hydrocarbon production. Here we look at the New Red Sandstone on Arran which is host to an impressive network of deformation bands.