Mid-proterozoic metamorphic rocks, metamorphism and crustal evolution in the west of liaoning province

摘要

Meteamorphic supracrustal rocks of mid-Proterozoic in the west of Liqoning province consist of quartzite, phyllite-schist, marble, fine-grained felsic gneiss and a small proportion of actinolite schist, being a transgressive sedimentary cycle with intermediate-acid volcanic activity and subalkalic basaltic magmatic activity. The majority of metamorphic plutonic rocks are plagiogranitic gneisses. According to the Rb-Sr isochron age, paleontology and stratigraphic contact relation, and so on, we think they are mid- Proterozoic intrusion.