古地理学报Issue(6)：926-934,9.DOI:10.7605/gdlxb.2014.06.073
藏北羌塘盆地中央隆起带下二叠统展金组沉积岩稀土元素地球化学特征及其地质意义
REE geochemical characteristics and geological significance of sedimentary rocks of the Lower Permian Zhanjin Formation in central uplift zone of Qiangtang Basin,northern Tibet Plateau
摘要
Abstract
There is a hot debate on the Neopaleozoic tectonic evolution history of central uplift zone of Qiangtang Basin,northern Tibet Plateau.The clastic sedimentary strata,with great geological significance for the research on palaeogeography and tectonic setting of study area,were discovered in the Lower Per-mian Zhanjin Formation of the Well Qiangzi 5 in Jiaomuri area of central uplift zone.Based on the rare earth element (REE) geochemical analysis of 17 samples of silty mudstone and muddy siltstone,the data show that the ΣREE is entirely high,and the ratios of ΣLREE /ΣHREE and LaN /Yb N indicate that the differentiation is slight.The Ce anom , Ce /Ce * and Eu /Eu * ratios suggest that the sedimentary rocks of Zhanjin Formation formed in a certain depth of shallow water.The Lan /Yb n values decrease gradually from bottom to top in the Well Qiangzi 5,which reflects that the sedimentary rate at the bottom sequence is low-er than at the upper sequence.The REE geochemical characteristics and relative parameters imply that the sedimentary rocks of Zhanjin Formation were mainly derived from the basalt and sedimentary rocks.The critical characteristic parameters,as well as the La-Th-Sc tectonic discrimination diagram imply an arc-like tectonic setting for the depositional basin of Zhanjin Formation.关键词
羌塘盆地/中央隆起带/二叠系/展金组/稀土元素特征/地球化学Key words
Qiangtang Basin/central uplift zone/Permian/Zhanjin Formation/REE character-istics/geochemistry分类
天文与地球科学引用本文复制引用
胡俊杰,李琦,方念乔,杨静懿,黄静,陈若瑜..藏北羌塘盆地中央隆起带下二叠统展金组沉积岩稀土元素地球化学特征及其地质意义[J].古地理学报,2014,(6):926-934,9.基金项目
中国地质调查局“羌塘盆地油气地球化学实验技术及应用研究”项目（编号12120112211 12）资助 （）
