Abstract
Abstract The main mesoscopic features of the ductile deformation in the Hongusan region of the Ryoke Belt can be explained in terms of a single deformation phase, Dm. The associated stretching lineation is roughly east–west and has an associated top‐to‐the‐west sense of shear. This information fills an important gap in our knowledge about the deformational history of the Ryoke metamorphic belt. Andalusite porphyroblasts are well‐developed in the Hongusan area and their microstructure can be used to link the deformational history with the metamorphism. However, the andalusite porphyroblasts show both intertectonic and post‐tectonic microstructures. Some porphyroblasts have an intertectonic core and post‐tectonic rim. Analysis of associated metamorphic minerals and bulk‐rock chemistry suggests that the distinct types of microstructure can be explained in terms of distinct formation reactions related to regional and contact metamorphism. The intertectonic microstructure shows the presence of a deformation pre‐dating Dm, referred to as Dc. These two deformation stages are sufficient to account for all the main deformation features. The distribution of post‐tectonic andalusite growth shows a very broad thermal effect around an intrusion in the area. This can help place constraints on the thermal history of the Ryoke metamorphic belt.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.