Geological and Geochemical Characteristics of the Lilaozhuang Iron Mine in Huoqiu Iron Deposit: Implications for Sedimentary Environment
详细信息
- 责任者：Huang Hua (College of Earth Sciences ; Chengdu University of Technology ; Chengdu 610059 ; China) ; Zhang Lianchang
- 刊名：Acta Petrologica Sinica
- 出版年：2013
- 卷期：29(7)
- 关键词：铁矿 ; iron ores ; 岩石地球化学 ; lithogeochemistry ; 安徽 ; Anhui Province
- 页码：p.2593-2605
- 图表：10 illus., 2 tables, 48 refs.
- 分类号：1001
- issnNo：ISSN1000-0569
- isbnNo：CN11-1922/P
摘要
The Lee Laozhuang iron mine lies in the central parts of Anhui Huoqiu iron deposit which is tectonically located in the southern margin of the North China Craton. The iron ore body is hosted in biotite quartz hornblende plagioclase gneiss ( schist) and marble,both of their protoliths are fine-grained clastic rocks and magnesium-rich carbonate rocks,respectively. The iron ore body is mainly occurred as banded,disseminated and massive. Petrology and mineralogy study are conducted on samples from the Lee Laozhuang iron mine,while major and trace element compositions were analyzed on the iron ores and surrounding rocks. The results have shown that Lee Laozhuang iron ores are mainly composed of Fe 2 O 3 ,SiO 2 ,MgO with low content of Al 2 O 3 and TiO 2 . The trace element compositions and total contents of rare earth element are low. The iron ore samples have ( La / Yb) PAAS of 0. 2 ～ 0. 5,significant positive anomaly in La ( La / La * = 2. 07 ～ 4. 03) 、Eu ( Eu / Eu * = 1. 72 ～ 3. 60) and Y ( Y / Y * = 1. 50 ～ 1. 87) . They have high Y / Ho ( Y/Ho =38. 4 ～47. 31 with an average of 42. 12) and Sr/Ba ( Sr/Ba =4. 92 ～28. 90 with an average of 13. 68) . These characteristics demonstrated that metallogenic materials of the Lee Laozhuang iron mine are mainly sourced from the mixture of hydrothermal and seawater. The banded iron formations have no significant negative anomaly of Ce ( Ce / Ce * = 0. 67 ～ 0. 81) ,in combined with low Fe 2 O 3 T / FeO ( Fe 2 O 3 T / FeO = 2. 60 ～ 3. 19 with an average of 2. 95) ,indicating it is the primary ore. In addition,the geochemical analysis have shown that the protoliths of schist and gneiss within iron ore in the Lee Laozhuang iron mine may be formed from clays or sandy sedimentary rocks of the continental margin,suggesting that the seawater was reduced with low oxygen fugacity during the iron ore precipitation. The normalized REE pattern have shown strongly LREE depletion and HREE enrichment with a wide range ( La / Yb) N ( 8. 46 ～ 25. 78 with an average of 19. 48) ,indicating deposited materials are possibly sourced from terrigenous contribution. In summary,the Lee Laozhuang BIF iron mine was formed in confined basins of active continental margin,which was influenced by the submarine volcanic hydrothermal activities.
© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号 地址：北京市海淀区学院路29号 邮编：100083 电话：办公室：(+86 10)66554848；文献借阅、咨询服务、科技查新：66554700 |