Abstract:

Yemaquan large-scale deposit, found in recent years in the Qimantage area, Eastern Kunlun, is related to intrusive rock and is skarn type iron copper polymetallic deposit. Using zircon LA-ICP-MS U-Pb method, the authors measured the Yemaquan granodiorite formation age for (392.4±2.2) Ma, which belongs to the Variscan Stage. Previous use of molybdenite Re-Os method obtained isochron age of skarn type copper-molybdenum polymetallic ores and skarn type molybdenum ores which are (225.0±4.0) Ma (n=7,MSWD=0.24) and (230.1±4.7) Ma (n=5, MSWD=0.12). In the stage of hydrothermal superimposition, in mineralization periods, early metallogenic hydrothermal is likely to be provided by Yemaquan granodiorite (392.4±2.2 Ma). Since there are much acidic rocks in this area, the intermediate-acid rock mass may be the main source for iron-copper polymetallic deposit; therefore, the intrusive body formation age, in the search for skarn type iron-copper polymetallic deposit, not only has important theoretical significance, but also has important practical significance.

Key words: granodiorite, diagenetic age, Fe-Cu deposit, Yemaquan, Qimantage, Eastern Kunlun