Geothermal Controlling Structures
The secondary permeability (i.e. faults and fractures) involved in rock formations is typically the predominant control of fluids in geothermal reservoirs. The structural controls of this permeability have been studied in detail by James E. Faulds in the Basin and Range where he demonstrated that certain structural settings are more favorable than others (reference: http://www.atlasgeoinc.com/wp-content/uploads/GRC2011-Faulds.pdf).
Faults, fault intersections, pull-aparts,and fissures in various forms and orientations are often host to geothermal systems. Some non-structural attributes are also grouped into this category such as the gaps boundaries between intrusions and host rock or between different strata, as well as lithographically controlled systems (those where porosity of a formation is a primary contributor to the reservoirs hydrology).