青海水泉子地区晚奥陶世侵入岩岩石学特征及构造环境分析

ROCK GEOCHEMICAL CHARACTERISTICS AND TECTONIC ENVIRONMENT OF LATE ORDOVICIAN INTRUSIVE ROCKS IN SHUIQUANZI AREA OF QINGHAI PROVINCE

结合水泉子地区地质背景,对晚奥陶世侵入岩地质、岩相、岩石化学、稀土元素、微量元素等地球化学特征进行了总结和分析。研究结果显示,岩石构造环境为活动大陆边缘的岛弧,与该地区晚奥陶世的洋盆闭合作用有关,是与俯冲汇聚构造环境有关的大陆弧型花岗岩,为东昆仑西段祁漫塔格加里东期洋壳的存在提供了直接证据。

Based on the geological background of Shuiquanzi area,the geochemical characteristics,such as geology,petrography,petrochemistry,rare earth elements and trace elements of the Late Ordovician intrusive rocks were summarized and analyzed. The results showed that the rock tectonic setting was the island arc of the active continental margin,which was related to the closure of the Late Paleozoic oceanic basin in the area. It was the continental arc granite associated with the subduction structure. It was the western part of the East Kunlun Mountains. The presence of the eastern oceanic crust provided direct evidence.