Abstract
Anisotropy of magnetic susceptibility (AMS) was measured in the Namwon granite body (217–176 Ma), southwest Korea, along with some microscopic observations. It was revealed that the Namwon granite has subvertical magnetic foliation and subhorizontal magnetic lineation, but only weak signs of solid-state deformation. The trend of the magnetic foliation and lineation dextrally converges into the trend of the Sunchang shear zone (NNE) along the western margin of the Namwon granite body. The patterns of the magnetic foliation and lineation, as well as the weak signs of solid-state deformation, suggest that the magnetic fabrics reflect the synplutonic flow pattern of the Namwon granite influenced by the dextral ductile shearing along the Sunchang shear zone. Although the Namwon granite was considered as post-tectonic pluton, i.e., a pluton that postdated the dextral shearing along the Sunchang shear zone, the dextral movement must have lasted after the full consolidation of the Namwon granite body.
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Otoh, S., Jwa, YJ., Nomura, R. et al. A preliminary AMS (anisotropy of magnetic susceptibility) study of the Namwon granite, southwest Korea. Geosci J 3, 31–41 (1999). https://doi.org/10.1007/BF02910232
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DOI: https://doi.org/10.1007/BF02910232