Abstract:
Petrographic study and Dickison's framework component statistical analysis show that the Permian sandstones are mainly feldspathic litharenite, and the debris was mainly derived from immature components. The data of major elements, minor elements and rare earth elements indicate that the tectonic setting of the provenance was continental island arc, with the sandstone debris mainly derived from upper crustal felsic rocks. The Permian sandstones, from old to young, are characterized by transition from recycled orogenic belt to magmatic provenance. In combination with petrological studies, the authors hold that the tectonic setting of the Permian sandstones tended gradually to become stable, which recorded the final closure process in the eastern part of the central Asian orogenic belt.