3.9.8 Fault System (Forkastningssystem)
3.9.8.1 A fault system consists of two or more intersecting or geometrically associated faults or fault sets assumed to have been formed during the same faulting episode (Fig. 17).
3.9.8.2 Fault system, like fault zone and fault complex, ranks next above fault.
3.9.8.3 No limitations are placed on the extent of a fault system beyond those applying to the individual faults in the system.
3.9.8.4 The structure is mappable with the help of geomorphological, geological and/or geophysical methods.
3.9.8.5 The individual faults in the fault system may have identical or different structural character (see Section 3.9.4.5).
3.9.8.6 A fault system should preferably be defined formally and is named in accordance with the "general rules for naming and defining geological units" (Chap. 2) and the provisions of Section 3.9.1. The proper name (Section 2.2.2) is placed between the words "the ... Fault System" in the compound name.
3.9.8.7 Fault systems are usually dominated by faults of one main type, normal, lateral or reverse faults. However, local variations in orientation of the principal stress axes may occur giving rise to genetically associated faults of two or all three main types within a single fault system. The locations of fault systems can be predetermined by older zones of crustal weakness. Fault systems can therefore be underlain by or associated with faults that were active during an earlier deformational episode.
3.9.8.8 Examples: No formally named fault systems are known from Norway or Norwegian territories. Several genetically associated fault sets on the continental shelf are likely to be fault systems according to the present definition. Faults that can most readily be defined as belonging to a single fault system are those formed in the roof rocks of rising magmatic bodies, salt domes and diapirs.
3.9.8.9 Key reference: Fault system has previously been used synonymously with fault set (Bates & Jackson 1980).
