Early Paleozoic Intermediate-Acid Magmatic Activity in Bairiqiete Area along the Buqingshan Tectonic Melange Belt on the Southern Margin of East Kunlun Mountains : Constraints from Zircon U-Pb Dating and Geochemistry
详细信息
- 责任者：Liu Zhanqing (Key Laboratory of Western Mineral Resources and Geological Engineering ; Ministry of Education ; School of Earth Science and Resources ; Chang’an University ; Xi’an 710054 ; China) ; Pei Xianzhi
- 刊名：Geology in China
- 出版年：2011
- 卷期：38(5)
- 关键词：岩浆活动 ; igneous activity ; 混杂堆积 ; melange ; 酸性岩 ; acidic rocks ; 中性岩 ; neutral rocks ; 铀—铅计时 ; U-Pb dating ; 昆仑山 ; Kunlun Mountains
- 页码：p.1150-1167
- 图表：12 illus., 3 tables, 55 refs.
- 分类号：0801
- issnNo：ISSN1000-3657
- isbnNo：CN11-1167/P
摘要
///Based on 1∶50 000 regional geological mapping on the southern margin of the East Kunlun Mountains and using methods of detailed field section measurement and petrologic analysis as well as LA-ICP-MS zircon U-Pb dating and geochemical investigation, the authors studied the intermediate-acid magmatic rocks in Bairiqiete area of the Buqingshan tectonic melange belt. The results show that the rocks are mainly granodiorite with 206Pb/238U average weighted age of (441±6) Ma (MSWD=0.75) and intermediate-acid volcanic rock such as rhyolite-porphyry with 206Pb/238U average weighted age of (438±3) Ma (MSWD=2.0). Geochemically, the former is characterized by high content of Si, Al and Na and should belong to the Na-enriched calc-alkali series, whereas the latter is of Si-saturated, aluminous and calc-alkali series.