The structural styles of the main Mesoproterozoic stratigraphic units in Zhangshiyan Geopark show obvious differences, with multiple angular unconformities. The most important one is the angular unconformity between the Mesoproterozoic Changcheng System and the Paleoproterozoic Gantaohe Group. This unconformity was formed by the Lüliang Movement, which led to the stabilization of the North China Plate. The Lüliang Movement coincided with the final formation of the Columbia supercontinent and has geological responses in Tarim of China, Africa, Australia, Siberia, North America, Eastern Europe, and other regions. It can be internationally compared with major tectonic events such as the Hudsonian Orogeny in North America and the Karelian Orogeny in Europe, giving it significant value for global tectonic correlation.
Simply put, this indicates that the underlying Neoarchean older strata underwent intense folding and uplift during the Wutai Movement. After long-term weathering and erosion, they were later covered by the deposition of overlying younger strata, leaving a long gap in the sedimentary record. This tectonic event not only caused folding of the strata, but was also accompanied by strong migmatization and large-scale granite intrusion. The Beitai granitic gneiss seen in Mount Wutai today is a clear marker of this thermal event. From a global perspective, this movement represents an important continental accretion and stabilization event of the North China Craton, also known as the Middle Plate, during the early Precambrian, making the ancient continental crust more stable.
These unconformities reflect multiple orogenic and epeirogenic movements, providing important evidence for reconstructing the geological evolution history of the Central Orogenic Belt of the North China Craton. They are of great significance for tectonic correlation and geotectonic research.