As the landmark rock of the continent, granite forms the basis of the upper crust of the continent, and the formation process of granite is usually closely related to the tectonic, metamorphic and mineralization of the continent. The origin of granite has been the subject of much debate since the 18th century, when geological science was still in its infancy. The debate on the origin of granite can be found in the treatises of Gilluly (1948), Pitcher (1993) and Young (2003), which will not be listed here. What needs to be mentioned is that since the plate tectonic theory came out in the 1960s, many explanations about the origin of granite have been re-recognized within the theoretical framework of plates. In many cases, consensus appears to be converging, but actual debate continues.

The misunderstanding of Bowen's (1914, 1922, 1948) theory of basaltic magma crystallization differentiation is to combine the sequence of mineral crystallization with the rock sequence of magmatic rocks from basic to acidic. Experimental results prove that the crystallization and fractionation of basaltic magma can only produce a small amount of residual granitic melt, which obviously conflicts with the fact that there are many granites in the field (Holmes, 1926; Read, 1957). The mineral reaction series can actually be applied to magmatic systems of different compositions. In other words, the initial crystallization from the magmatic system is not necessarily basic rock, and the last formation is not necessarily felsic (acidic) rock, because the nature of the rock crystallized from the melt depends on the composition of the melt rather than the order of mineral crystallization (Kennedy, 1933). Walton (1960) once commented on Bowen's understanding as follows: "There is nothing wrong with Bowen's chemical theory or its application to the separation of basaltic magma, which is still a basic principle of petrology. But However, igneous theory is rigidly bound to a single model, and it is somewhat speculative to suggest that the evolution of most igneous rocks is due to the intrusion of basaltic magma into the crust to cool, crystallize and separate. The same chemical theory can be applied to other models."

In the 1940s (Gilluly, 1948), the debate between the "becoming theory" represented by H. H. Read and the "magma theory" represented by N. L. Bowen, as more and more scholars agreed The magma origin of granite ends. However, where does the magma that makes up the granite body come from? In Bowen's words: When the granites? (Where does the granite come from?)

The overwhelming understanding on this issue is that granite is formed by the partial melting and solidification of rocks of various compositions in the earth's crust. This point of view combines two different understandings of the origin of granite in the early days: magmatism (thinking that granite comes from the crystallization of magma) and becoming theory (thinking that granite is a silicon-aluminum-rich sedimentary rock that undergoes granitization under dry or water-bearing conditions. transformed). It is proposed that granite is the result of ultra-metamorphism (deep melting) of crustal rocks, which is of great significance to the study of the origin and chemical differentiation of the crust, because they are related to the thermal state of the crust and the composition of the protolith in a specific period, including How much granite magma can be produced, the temperature at which the granite was formed and the amount and source of water, the tectonic setting and the process of plate action, etc.