成都理工大学学报（自然科学版）2012，Vol.39Issue(4)：362-371,10.
黑龙江金厂金矿花岗斑岩锆石地球化学、U-Pb年代学及地质意义
Geochemistry and U-Pb geochrony of zircon from granite porphyry of Jinchang gold deposit in Heilongjiang, China and its geological significance
摘要
Abstract
The Jinchang gold deposit, located in the east segment of the Central Asian orogenic belt, is a large hydrothermal deposit associated with the Mesozoic magmatic activities. In order to determine the type, age and tectonic setting of the metallogenic magmatic rock, the authors measure the U-Pb dating and in situ trace elements of the zircons from granitic porphyry by cathodoluminescence (CL) images and LA-ICP-MS. All zircon grains have fine oscillatory zonings in CL images, and the ratio of Th/U is >0. 4, indicating their magmatic origin. Zircon U-Pb dating is 220 Ma and 103~ 123 Ma, representing the two-phase magmatic events. The zircon with age of 220 Ma belongs to the captured magmatic zircon. Correspondingly, zircons with ages of 103～123 Ma are derived from the new magma. Geochemistry and U-Pb dating of the zircons suggest that the captured zircon was derived from the Early Triassic granite porphyry. The trace elements of the zircons indicate that the granite porphyry originated from the highly melting and crystallization differentiation and the emplacing in the oxidizing environment in the shallow crust of the Early Triassic granite. The values of negative Eu anomalies in zircons from the new magma decreased in the oxidizing environment. The weighted average U-Pb age (113. 5 + 3. 8 Ma) of zircons from new magma is identical with the metallogenic age. Therefore, the Early Cretaceous magmatic event directly resulted in the gold mineralization in the Jinchang deposit. The mineralization occurred in lithospheric extensional setting related to the subduction of the Pacific Plate.关键词
锆石地球化学/锆石U-Pb年代学/岩浆锆石/地质意义/金厂金矿Key words
zircon geochemistry/ zircon U-Pb geochronology/ magmatic zircon/ geological significance/ Jinchang gold deposit分类
天文与地球科学引用本文复制引用
钱烨,孙丰月,李碧乐,陈静,第五春荣..黑龙江金厂金矿花岗斑岩锆石地球化学、U-Pb年代学及地质意义[J].成都理工大学学报（自然科学版）,2012,39(4):362-371,10.基金项目
中国地质调查局项目(资[2011]02-36-06) （资[2011]02-36-06）
