Magnetic fabric separation and analysis of rock tectonic deformation

Both detailed rock magnetism and structural analysis suggest that the routine anisotropy of magnetic susceptibility (AMS) measurements can not suffice for the interpretations of complicated tectonic deformation, because AMS is the result of all the magnetic minerals contribution. In this paper, we reviewed the measurements of anisotropy of anhysteretic remanence (AARM), low-temperature AMS (LT-AMS), and high-field AMS (HF-AMS) to separate different components in the AMS. Thus, contribution of multiple magnetic minerals to AMS can be obtained quantitatively, which will contribute to different tectonic interpretations. On this basis, we described the theoretical basis, technological innovations, and its application prospect of AMS separation methods for the different magnetic components in deformed rocks. We also discussed the complexities and limitations of the shape factor (T) and the degree of anisotropy (P-j) in grain-scale single crystals for the interpretation of tectonic deformation. Finally, some typical examples of separation of magnetic fabric and its applications in orogeny strain analysis were listed.