## 5 Discussion  
### Regularity of Mineralization and Alteration Zoning  
The typically lateral and vertical alteration zone of porphyry copper deposits was first proposed by [PERSON] and [PERSON] [6], including concentric-banded alteration zones of potassic, phyllic, argillic, and propylitic zones, with typical hydrothermal mineral associations within each zone, as well as metal sulfide minerals and related mineralization zones displayed in various occurrences. [PERSON] [2] and [PERSON] et al. [9] summarized the consistent mineralization and alteration zoning pattern in porphyry copper systems, which comprises sodic-calcic, potassic, chlorite-sericite, sericitic, and advanced argillic zones centrally from the bottom upward or outward. Similar to that of typical porphyry deposits, the Beiya deposit exhibits mineralization-alteration zoning of potassic, phyllic (pyritic-sericitic), propylitic, and argillic alteration from the center outward or upward (Figure 4). However, the propylitic zone is not fully developed and is absent or overprinted by the argillic zone in some areas (Figure 4). Wall-rocks, especially the Beiya Fm. limestones, have an influential impact on mineralization and alteration in the Beiya deposit, just as they do in other porphyry copper deposits worldwide [2], which results in contact and wall-rock alteration and the corresponding hydrothermal vein-type mineralization.  
Additionally, it displays mineralization occurrence zoning at Beiya. Porphry-type mineralization commonly occurs in veins and veinlets; skarn-type mineralization appears as long and thick veins or irregular-shaped veins; hydrothermal vein-type and distal hydrothermal-type mineralization occur in veins, bedded, near bedded, and lenticular shapes; oxidizing-leaching enriched mineralizations are mainly sack-like or irregular in shape. These various occurrences are dominantly controlled by structures and lithologies, which are generally observed in many porphyry and associated deposits [2; 4; 37; 38].  
The element migrations of different zones further reflect their alteration and mineralization characteristics. In the potassic and phyllic zone, the high temperature metallogenic element associations of Cu, Mo, Bi, and Au are significantly enriched, while the low temperature metallogenic element association of Pb, Zn, and Au significantly increases outward in wall-rock alteration zone (Table 1; Figure 7), demonstrating an obvious metallogenic element association zoning that consistent with the spatial interrelationships of mineralization in the porphyry copper system [2] and confirming a recent study that the alteration zones in the porphyry deposit result from gradual cooling of a single magma-hydrothermal continuous interaction with porphyry intrusion [12]. The gain and/or loss of oxides in different zones reflects the primary generation or replacement of hydrothermal minerals. In the wall-rock mineralization-alteration zone, there is a decrease in Na\({}_{2}\)O, MgO, and CaO with an increase in Fe\({}_{2}\)O\({}_{3}\)\({}^{*}\), SiO\({}_{2}\), K\({}_{2}\)O, and Al\({}_{2}\)O\({}_{3}\), reflecting the development of an amount of pyrite, magnetite, quartz, and some clay minerals and the replacement of calcite and dolomite. In the potassic zone, K\({}_{2}\)O, MgO, and Fe\({}_{2}\)O\({}_{3}\)\({}^{*}\) are slightly enriched, while SiO\({}_{2}\), Al\({}_{2}\)O\({}_{3}\), and CaO slightly decrease, indicating the formation of K-feldspar, hydrothermal biotite, and pyrite and the replacement of plagioclase. In the phyllic zone, Na\({}_{2}\)O, SiO\({}_{2}\), and Fe\({}_{2}\)O\({}_{3}\) are enriched, with K\({}_{2}\)O, Al\({}_{2}\)O\({}_{3}\), CaO, and MgO decrease, reflecting the formation of some quartz, sericite, and pyrite and the replacement of plagioclase or mafic minerals.