It is common practice in nickel sulfide mines and exploration projects to refer to any breccia-textured or vein-hosted sulfide as “remobilised”, with the implication being that it has been moved by tectonic processes away from its original site of deposition. One of the central messages of this contribution is that, while tectonic dislocation or re-emplacement of sulfide bodies certainly can happen during deformation, it should not be automatically assumed that any sulfide ore mass lying outside its original host has necessarily been “remobilised”. In many of the cases illustrated here, the sulfide liquid invaded its floor or wall rocks at magmatic temperatures by essentially igneous processes that were an integral part of the primary ore-forming event. We recommend that the criteria for recognizing durchbewegung breccias should be applied before describing any sulfide body as “remobilised”, and that where these criteria are lacking, or ambiguous, then purely descriptive terminology should be used. This is critical to understanding orebody geometry during resource delineation: truly remobilized ores will have their geometry determined by the orientation of the stress field at the time of deformation, not at the time of emplacement, and consequently may bear no relationship to the geometry of the host igneous body.
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