- 责任者：Qi Tianjiao (State Key Laboratory of Geological Processes and Mineral Resources ; China University Geosciences ; Beijing 100083 ; China) ; Xue Chunji
- 刊名：Earth Science
- 出版年：2012
- 卷期：37(6)
- 关键词：铁矿 ; iron ores ; 基性岩 ; basic rocks ; 新疆 ; Xinjiang
- 页码：p.1315-1326
- 图表：6 illus., 2 tables, 47 refs.
- 分类号：1001
- issnNo：ISSN1000-2383
- isbnNo：CN42-1233/P
The basic igneous rock in Cihai giant iron district has a close relationship with the iron mineralization which is the key to understanding of the larger scale of iron metallization and the metallogenic setting.The diabase is the main basic igneous rock in Cihai iron district,and the platy iron-vein group are hosted by the fault-fissures in diabase;the U-Pb dating of single-grained zircon from diabase yielded an average weighted 206Pb/238U age of 263.8±3.6Ma（n=11,MSWD=1.3）which is contemporary with that of the basic igneous rock in Permian Tarim basin,eastern Tianshan orogenic belt and Beishan tectonic-metallogenic belt.The trace elements chondrite-normalized patterns of basic igneous rock in Cihai iron district are relatively flat with Sr,Ba enriched and Nb lost lightly;the REE chondrite-normalized patterns are flat.The content of trace elements and magmatic nature of basic igneous rock in Cihai iron district are similar to that of the basic igneous rocks in Permian Tarim basin,eastern Tianshan orogenic belt and Beishan tectonic-metallogenic belt and they all belong to alkaline-calc-alkaline series with close genetic relationship;the basic igneous magma of Cihai district most possibly originated from asthenospheric mantle.The basic igneous rock in Cihai district is possibly apart of Tarim large igneous provinces formed by Permian mantle plum;and the large scale of iron mineralization are also formed in the setting of mantle plum which is a branch of mantle plum in Tarim basin as Beishan tectonic-metallogenic belt.