Research status and progress of Paleozoic ophiolites in Beishan orogenic belt

As one of the most important parts of orogenic belt, the formation and emplacement of the ophiolitic mélange belt is closely related to regional orogenic events.Four ophiolitic mélanges belts are involved in the Beishan orogenic belt, of which the Hongliuhe-Niujuanzi-Xichangjing ophiolitic mélange belt is the oldest one, indicating that the Bishan Ocean was opened as early as Early Cambrian, and might be closed in Permian at the latest.The study of tectonic affinity also shows that the evidence for the division of the discovered ophiolitic mélange zones as the first-scale tectonic unit is still insufficient.Because the identification, formation, emplacement age of ophiolites and evolution of various ocean basins, as well as their tectonic properties are restricted by objective expression about geological survey of Beishan ophiolite belts, it is suggested that one of the key means to further study and solve hot issue in the area in the future is to pay attention to the large scale fine basic geological survey of each ophiolite belt.