UK structure site report : Boddam Fault, Peterhead Granite

Understanding the architecture and connectivity of faults and fractures in granitic intrusions is critical for understanding fluid-flow in deep geothermal systems (DSGs). The Boddamfault zone cross-cuts the Peterhead granite, andprovides an excellent analogue for the subsurface expression of fault and fracture zones in granitic bodies. The fault system comprises offset NNE-SSW striking fault segments inferred to link at a relay zone, at BoddamCastle, via NE-SW sinistral and NW-SE dextral strike-slip faults. A series of N-S high-angle reverse faults also occur, but their relationship to the fault zone is uncertain. The relay zone displays a high fault and fracture density and connectivity which could contribute to enhanced fluid flow in the system. The work suggests that fault relay zones could be considered as higher-permeability targets for geothermal exploration.