摘要
对安徽铜陵新桥铜-硫-铁-金矿床区内的石英闪长岩和辉绿岩中的锆石分别进行了SHRIMP精确定年研究,石英闪长岩中锆石206Pb/238U年龄为(140.4±2.2)Ma,辉绿岩中锆石的年龄较复杂,其中发现了元古代锆石颗粒,其锆石207Pb/206Pb年龄为(2261±14)Ma,(1612±8)Ma,(919±12)Ma,(831±17)Ma。另外还有一组早古生代年龄的锆石,锆石206Pb/238U年龄为(443±13)Ma。以上这些新资料说明该区可能存在元古代基底的信息,且燕山期岩浆活动对本区成矿具有重要意义。
High-precision SHRIMP U-Pb dating was performed on zircon from quartz diorite and diabase in the Xinqiao Cu-S-Fe-Au deposit, Tongling ore district, Anhui. Zircon from quartz diorite yielded a 206Pb/238U age of (140.4±2.2) Ma, while the zircon age of diabase is relatively complex. Several Proterozoic zircon grains were found in diabase, which yielded 207Pb/206Pb ages of (2 261±14) Ma, (1 612±8) Ma, (919±12) Ma and (831±17) Ma. In addition, there is also a group of Early Paleozoic zircon grains, whose 206Pb/238U age is (443±13) Ma. The above new data give the information of the possible existence of Proterozoic basement in this district, and Yanshanian magmatism is of great significance for mineralization in the district.
出处
《中国地质》
CAS
CSCD
2004年第2期169-173,共5页
Geology in China
基金
国土资源部国际合作与科技司重点项目(20010209)
中国地质调查局地质大调查项目(200110000004)
国土资源部专项(20010103)资助。