黑龙江宁安英城子热液金矿床与成矿伴生的辉绿玢岩的锆石U-Pb年龄及其地质意义

Zircon U-Pb dating of associated diabase prophyrite with Yingchengzi hydrothermal gold deposit in Ning'an, Heilongjiang and their geological significance

英城子热液金矿床产于张广才岭岩浆构造带东侧的早古生代花岗岩岩体内的韧脆性剪切带中。矿区内出露的辉绿玢岩中锆石的SHRIMPU--Pb测年结果表明:16个单颗粒锆石的谐和年龄值可划分为4组,分别为849.7～897.0Ma、755.6±19.2Ma、486～514.0Ma和419～451Ma。结合锆石的特征和相关地质测年结果,初步认为辉绿玢岩岩浆作用发生在麻山期或加里东期陆内造山后的地壳伸展环境内(432Ma);该区在晚元古代和早古生代属于佳木斯地块的一部分或地壳演化与佳木斯地块、额尔古纳地块处于相同的地质环境中。

Yingchengzi hydrothermal gold deposit is located in the ductile-brittle shear zone of Early Paleozoic granite body from the east of Zhangguangcailing magma tectonic belt. The zircon SHRIMP U-Pb dating of diabase porphyrite cropout in the mine field indicates that the concordant ages of 16 single-grain zircons can be divided into four groups,including 849. 7 ～ 897. 0 Ma,755. 6 ± 19. 2 Ma,486 ～ 514. 0 Ma and 419 ～ 451 Ma. Combining with zircon characteristics and related geological dating data,the authors preliminarily confirm that the magmatism of diabase porphyrite occurred in continental post orogenic extensional setting （432 Ma） of Mashan or Caledonian periods. This area belongs to a part of Jiamusi Massif in Late Proterozoic and Early Paleozoic,or its crustal evolution was in the same environment as Jiamusi and Ergun massifs.