| The study area is located in the southwestern part of the South China Block and the southern part of the Nandan-Binyang metallogenic belt.A systematic sampling of granite samples was carried out in Kunlunguan area.A temperature-time simulation of apatite fission track dating,apatite(U-Th)/He dating,and apatite fission track was performed.This paper quantitatively calculates the uplift rate and erosion amount of the Kunlunguan pluton,preliminarily constructs the history of thermal evolution since the Mesozoic-Cenozoic in the Kunlunguan pluton,discusses the relationship between the uplift process of the rock mass and the regional tectonic events,and predicts the preservation potential after the formation of the deposit in the study area.The fission track length of apatite is 12.1±0.4~13.4±0.4?m.The average length of the samples is not much different,but the overall length is small,indicating that the sample has been retained in the annealing zone for a long time.The average age test results for apatite(U-Th)/He were: 45.4Ma,35.4Ma,34.7Ma,39.3Ma.The age values of apatite fission track are 63.6Ma,51.4Ma,56.0Ma and 86.8Ma.The results of the test are less than the age of rock formation,indicating that the samples undergo annealing process and record the age after tectonic movement.Through the test results and time-temperature simulation,the cooling rate of the sample is calculated to be 0.18~4.39 ? /Ma,the uplift rate is 5.9~146m/Ma,and the denudation amount is 1.3~1.8Km by the age-closed temperature calculation method.It is preliminarily considered that after the formation of the Kunlunguan pluton,it experienced a very rapid cooling process(102~94.3 Ma),followed by two rapid uplifting cooling processes(63.3~51.4 Ma)and(33.6~20.1 Ma).Compared with the regional tectonic events,it is considered that the last two uplifts may be related to the lateral collision of the Indo-Asian plate and the strike slip movement of the Ailao Mountain-Honghe shear zone.According to the results of this paper,the metallogenic depth of Sn ore deposit,ZnCu ore polymetallic deposit in the study area are compared.It is presumed that the Sn polymetallic ore deposit in the study area has undergone partial denudation,the Zn-Cu ore deposit has been denuded to a lesser degree,and there is also a greater prospecting potential in the deep. |
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