The Tangba Gold District is located in the eastern part of the southern mineralization sub-belt of the West Qinling gold ore belt.The gold ore bodies are mainly distributed in the fault structures near the hanging and foot walls of granite porphyry,or in the granite porphyry.The granite porphyry is closely related to gold mineralization.The geochemical analysis of the rock shows that the granite porphyry in the study area has high silicon (w(SiO₂) 70.84 %-75.23 %),rich aluminum (w(Al₂O₃) 14.59 %-16.08 %),A/CNK=1.05-1.32(mean value 1.16),which is supersaturated type silicon aluminum,belonging to typical peraluminous granite; the total amount of rare earth elements is low(30.72×10^-6-97.81×10^-6),LREE is enriched,HREE is depleted,and light and heavy rare earth fractionation is obvious(w(La)_N/w(Yb)_N=3.77-18.64),with moderate negative europium anomaly(δEu=0.55-0.82,average 0.67); trace element characteristics are characterized by large ion lithophile element enrichment and high field strength element relative loss.The zircon U-Pb dating results of LA-ICP-MS show that the diagenetic age of granite porphyry is 212.8 Ma±2.7 Ma,belonging to the Late Triassic.The rock mass may have formed during the ascending and emplacement process of the granitic magma formed by partial melting of sedimentary rocks dominated by the various sandstone components,and is a typical crustacean genetic type.The Tangba granite porphyry has the characteristics of post-collisional magmatism.It is the product of the partial melting of the crust under the thickening of the crust due to the collision of the North China plate and the Yangtze plate in Indosinian period.The granite porphyry formed in the transformation stage from the extrusion environment to the extension environment.