micro continental blocks collided and almagamated to form the craton, and different phases of metamorphism during Precambrian time from around 3 to 1.6 billion years ago. In Mesozoic to Cenozoic time (146-2.6 million years ago), the Precambrian basement rocks were extensively reworked or reactivated. Precambrian Tectonics (4.6 billion years ago to 1.6 billion years ago) Precambrian tectonics of the North China Craton is complicated. Different scholars have proposed different models to explain the tectonics of the Craton, with two dominant schools of thought come from Kusky (2003, 2007, 2010) and Zhao (2000, 2005, and 2012). The major difference in their models is the interpretation of the two most significant Precambrian metamorphic events, occurring 2.5 billion years ago and 1.8 billion years ago respectively, in the North China Craton. Kusky argued that the metamorphic event 2.5 billion years ago corresponded to the amalgamation of the Craton from their ancient blocks, while Zhao argued that the later event was responsible for the amalgamation. Kusky's Model: The 2.5 Ga Craton Amalgamation Model Kusky's model proposed a sequence of events showing the microblocks amalgamating 2.5 billion years ago. First, in the Archean time (4.6-2.5 billion years ago), lithosphere of the craton started to develop. Some ancient micro-blocks amalgamated to form the Eastern and Western Blocks 3.8 to 2.7 billion years ago. The formation time of the blocks is determined based on the age of the rocks found in the craton. Most rocks in the craton were formed at around 2.7 billion years ago, with some small outcrops found to have formed 3.8 billion years ago. Then, the Eastern Block underwent deformation, rifting at the Western Edge of the Block 2.7 to 2.5 billion years ago. Evidences for a rift system have been found in the Central Orogenic Belt and they were dated 2.7 billion years old. These included ophiolite and remnants of a rift system. Collision and amalgamation started to occur in Paleoproterozoic time (2.5–1.6 billion years ago). From 2.5 to 2.3 billion years ago, the Eastern and Western Blocks collided and amalgamated, forming the North China Craton with the Central Orogenic Belt in between. The boundary of the Central Orogenic Belt is defined by Archean geology which is 1600 km from west Liaoning to west Henan. Kusky proposed that the tectonic setting of the amalgamation is an island arc, in which a westward dipping subduction zone was formed. The two blocks then combined