Abstract:

The tectonic evolution and the orogenic time of Bogda Mountain have been debated for a long time, and so far, few systematic researches  have been done on this issue. In this paper, based on field surveys and preview papers, the tectonic evolution of Bogda Mountain has been studied elaborately with the application of several methods such as magmatite characteristic, sedimentary recycle，paleo-current direction and sediment dispersal patterns analysis. The results show that the tectonic evolution of Bogda Mountain mainly experienced three stages of tectonic inversion, i.e. (1) a rifted trough of Middle-Late Carboniferous and a weak orogeny period at the end of  Late Carboniferous; (2) a rifted-basin of  Early-Middle Permian and a paleo-Bogda Mountain uplift-leveling period from Late Permian to Triassic and at the end of Late Triassic; and (3) a weak-extensional basin of Early-Middle Jurassic and intermittent uplift periods of present-Bogda Mountain from Late Jurassic to present. The structure belts with the northeast direction resulted from Indosinian movement in the Chaiwopu sag south to Bogda Mountain are potential exploration areas.

Key words: tectonic evolution, tectonic inversion, weak orogeny, paleo-Bogda Mountain, present-Bogda Mountain