Jiaodong Peninsula is the only known Late Mesozoic giant gold metallogenic system with unique metallogenic mechanism within the Precambrian metamorphic terrane in the world, it belongs to a new genetic type of Jiaodong-type gold deposits. The formation, change and preservation process of this metallogenic system is of great significance to enrich and perfect the theory of gold mineralization. Xiadian is a super-large gold deposit that located in the middle-south section of Zhaoping gold belt in Jiaodong Peninsula. It is a typical Jiaodong-type gold deposit, the main ore-hosting rocks are Late Jurassic Linglong granite and a small amount of hidden Early Cretaceous Guojialing granite. The magmatism and mineralization ages of this deposit have been precisely defined, but its fine evolution process and post-ore change and preservation are not effectively constrained. Therefore, the tectonothermal history of the deposit is comprehensively constrained by using magmatism-mineralization geochronology and apatite fission track thermochronology, and its controlling factors are revealed, so as to improve the understanding of this metallogenic system and provide support for the evaluation of deep prospecting potential. Zircon U-Pb dating results show that the Linglong and Guojialing granites are emplaced at 151.7 +/- 2.1Ma (2 sigma) and 125.8 +/- 1.6Ma (2 sigma), respectively. The 40Ar/39Ar ages of biotite and muscovite in the region indicate that the Linglong intrusion cooled slowly after emplacement and underwent ductile deformation. The Guojialing granitoid underwent syn-magmatic ductile deformation, followed by rapid cooling. Both intrusions cooled to 350 +/- 50 degrees C at ca.124Ma, and the transition from ductile deformation to brittle occurs in the region later. The 40Ar/39Ar age of hydrothermal sericite and the U-Pb age of hydrothermal monazite in the Xiadian gold deposit indicate that intense brittle tectonic events and gold mineralization occurred at ca.120Ma. In this paper, apatite fission track (AFT) analysis was carried out using 7 rock/ore samples collected from the 532 tunnel at the -652m level of the Xiadian gold deposit, including the hanging wall and footwall of Zhaoping detachment fault that underwent different degrees of deformation. Except for the secondary fault gouge samples from the hanging wall affected by abnormal thermal events, the median AFT age of the other six samples ranged from 32.5 +/- 1.7Ma (1 sigma) to 23.6 +/- 2.9Ma (1 sigma), and the AFT length are unimodal with slightly negative deviation characteristics. The average AFT length is lower than 14 mu m (range from 12.0 +/- 0.3 mu m to 13.8 +/- 0.3 mu m), indicating that the deposit monotonically slowly passed through the apatite partial annealing zone (125 similar to 60 degrees C) at approximately 32 similar to 23Ma and underwent a similar thermal history. Combining the existing thermochronology data and the zircon U-Pb and AFT data in this study, the tectonothermal history of the Xiadian gold deposit since the emplacement of the host rocks (Linglong and Guojialing intrusions) was reconstructed. The average cooling and denudation rate of the Xiadian gold deposit since ca.120Ma gold mineralization to nowadays is 1.8 degrees C/Myr and 0.059km/Myr, respectively. Thus, the total amount of denudation is 7km. Compared with the quantitative evaluation of the overall denudation degree and the deep mineralization potential of the northwest Jiaodong area and the maximum ore depth of the borehole similar to 1. 5km, it is concluded that the deep prospecting potential of the Xiadian gold deposit is promising. Jiaodong Peninsula is the only known Late Mesozoic giant gold metallogenic system with unique metallogenic mechanism within the Precambrian metamorphic terrane in the world, it belongs to a new genetic type of Jiaodong-type gold deposits. The formation, change and preservation process of this metallogenic system is of great significance to enrich and perfect the theory of gold mineralization. Xiadian is a super-large gold deposit that located in the middle-south section of Zhaoping gold belt in Jiaodong Peninsula. It is a typical Jiaodong-type gold deposit, the main ore-hosting rocks are Late Jurassic Linglong granite and a small amount of hidden Early Cretaceous Guojialing granite. The magmatism and mineralization ages of this deposit have been precisely defined, but its fine evolution process and post-ore change and preservation are not effectively constrained. Therefore, the tectonothermal history of the deposit is comprehensively constrained by using magmatism-mineralization geochronology and apatite fission track thermochronology, and its controlling factors are revealed, so as to improve the understanding of this metallogenic system and provide support for the evaluation of deep prospecting potential. Zircon U-Pb dating results show that the Linglong and Guojialing granites are emplaced at 151.7 +/- 2.1Ma (2 sigma) and 125.8 +/- 1.6Ma (2 sigma), respectively. The 40Ar/39Ar ages of biotite and muscovite in the region indicate that the Linglong intrusion cooled slowly after emplacement and underwent ductile deformation. The Guojialing granitoid underwent syn-magmatic ductile deformation, followed by rapid cooling. Both intrusions cooled to 350 +/- 50 degrees C at ca.124Ma, and the transition from ductile deformation to brittle occurs in the region later. The 40Ar/39Ar age of hydrothermal sericite and the U-Pb age of hydrothermal monazite in the Xiadian gold deposit indicate that intense brittle tectonic events and gold mineralization occurred at ca.120Ma. In this paper, apatite fission track (AFT) analysis was carried out using 7 rock/ore samples collected from the 532 tunnel at the -652m level of the Xiadian gold deposit, including the hanging wall and footwall of Zhaoping detachment fault that underwent different degrees of deformation. Except for the secondary fault gouge samples from the hanging wall affected by abnormal thermal events, the median AFT age of the other six samples ranged from 32.5 +/- 1.7Ma (1 sigma) to 23.6 +/- 2.9Ma (1 sigma), and the AFT length are unimodal with slightly negative deviation characteristics. The average AFT length is lower than 14 mu m (range from 12.0 +/- 0.3 mu m to 13.8 +/- 0.3 mu m), indicating that the deposit monotonically slowly passed through the apatite partial annealing zone (125 similar to 60 degrees C) at approximately 32 similar to 23Ma and underwent a similar thermal history. Combining the existing thermochronology data and the zircon U-Pb and AFT data in this study, the tectonothermal history of the Xiadian gold deposit since the emplacement of the host rocks (Linglong and Guojialing intrusions) was reconstructed. The average cooling and denudation rate of the Xiadian gold deposit since ca.120Ma gold mineralization to nowadays is 1.8 degrees C/Myr and 0.059km/Myr, respectively. Thus, the total amount of denudation is 7km. Compared with the quantitative evaluation of the overall denudation degree and the deep mineralization potential of the northwest Jiaodong area and the maximum ore depth of the borehole similar to 1. 5km, it is concluded that the deep prospecting potential of the Xiadian gold deposit is promising.
