摘要
西藏打加错南北向地堑系处于冈瓦纳大陆北缘,地堑系总体延伸方向(175~190°),延伸长度>50 km,延伸宽度5~15 km.根据该地堑构造带内发育的鱼鳞山组(N2Qy)玄武岩测年结果以及地堑构造带内发育的活动温泉,判断该地堑构造活动时期早于13.43 Ma,现今仍在强烈活动.在打加错地堑系东西两侧的地垒中共发现5处金属矿(化)点,各矿(化)点与中酸性岩体活动及近SN断裂构造有密切关系,特别是近南北向展布的中酸性小岩体更易形成斑岩型铜矿.
The S-N trending graben system in Dajiacuo area, Qinghai-Tibetan plateau, is located in the northern margin of Gondwana with extension direction of 175-190;, extension length;50 km and extension width of 5-15 km. According to the dating results of basalts in Yulinshan Formation and activities hot-springs de- veloped in the graben tectonic belt, it is considered that the tectonic activity of the graben is earlier than 13.43 Ma and the strong activity is still undergoing up to now. Five metallic mineral occurrences are found in the horsts developed in the eastern and western side of the Dajiacuo graben system, showing a close re- lationship of mineralization with intermediate-acid rocks and S-N-trending fault, especially those S-N-tren- ding intermediate-acid minor-intrusions are more favourable for forming porphyry copper deposits.
出处
《资源调查与环境》
2013年第4期249-256,共8页
Resources Survey & Environment
基金
中国地质调查局地质调查项目"西藏打加错地区4幅区调"(项目编码:1212011086038)资助
关键词
地堑
地垒
打加错
西藏
graben
horst
Dajiacuo area
Tibet