江南古陆变质基底地层年代的修正和武陵运动构造意义

江南古陆变质基底的研究中，最突出的基础地质问题依然是地层年代的精确标定。地层年代标定涉及到成矿地层的划分和对比及其构造演化的时限，也直接影响层控矿床找矿中涉及的基础地质问题。在最新的中国地层年表中，前寒武纪地层对比和构造背景解释已发生重大变化。本文依据扬子块体和华夏块体新元古代地层中最新的系列锆石U—Pb测年结果，初步揭示“江南古陆”变质基底地层火山事件和分布范围。结合全球格林威尔造山运动基本特征，对江南古陆变质基底地层年代的修正将有利于重新厘定江南造山带的成矿背景，提供层控矿床基础年代地层资料，为新的矿产资源大调查服务。

A revised chronostratigraphic dating of metamorphosed basement strata of Jiangnan old land and its implication for Wuling tectonic movement

In the study of metamorphosed basement of Jiangnan old land, the conspicuous fundamental geologic problem still is accurate chronostratigraphic ascertainment of the basement. The chronostratigraphic ascer- tainment of the basement not only involves division and correlation of metallogenic strata and time limit of structure evolution, but also has a direct influence on the study of fundamental geology problem related to prospecting of stratabound ore deposits. In the latest chronostratigraphic scale of China, the correlation of Precambrian strata and explanation of tectonic setting have changed a great deal. Basing on the latest se- ries of zircon U-Pb dating data for the Neoproterozoic strata of the Yangtze and Cathaysia blocks, this pa- per preliminarily reveals distribution of metamorphosed basement strata and volcanism in the Jiangnan old land. In combination with basic characters of the global Greenvill orogeny, the revision of Chronostrati- graphic dating of metamorphosed basement strata of the Jiangnan old land will be beneficial to reconfirm the metallogenic background of the Jiangnan orogenic belt, and provides fundamental chronostratigraphic data of stratabound ore deposits to serve the new-round survey of mineral resources.