摘要
目的准确测定南天山库勒湖蛇绿岩的形成时代,探讨其地质意义。方法采用激光剥蚀等离子质谱(LA-ICP-MS)法,对库勒湖蛇绿岩中辉长岩锆石进行U-Pb同位素定年。结果辉长岩形成年龄(或结晶年龄)为418.2 Ma±2.6 Ma(MSWD=0.80)。结论南天山库勒湖蛇绿岩的形成时代为末志留世—早泥盆世早期,与古南天山洋盆的俯冲-消减时代相当,它的形成很有可能与古南天山洋盆的俯冲-消减作用有关。
Aim Todate precisely for Kulehu opiolite, and discuss its geological implication. Methods Dating for zircons of gabbro from Kulehu ophiolite by LA-ICP-MS. Results The crystallizing age of magma of gabbro is 418. 2 ± 2. 6 Ma ( MSWD = 0. 80). Conclusion Kulehu ophiolite formed in Late Silurian to Early Devonian corre- sponding to the subducting time of Palaeo-southern Tianshan Ocean, and it stands a good chance that the formation of kulehu ophiolite is related to the subduction of Palaeo-Southern Tianshan Ocean.
出处
《西北大学学报(自然科学版)》
CAS
CSCD
北大核心
2007年第1期107-110,共4页
Journal of Northwest University(Natural Science Edition)
基金
中国地质调查局综合研究资助项目(2003130000631212010611804)
国家自然科学基金资助项目(40472044)