Ar-Ar Dating and Geochemical Characteristics of Qing-Longtai Diabase from the Liaohe Depression, North China: Finishing Time Restriction on Thinning Process of the Eastern North China’s Lithosphere
详细信息
- 责任者：Li Jun (School of Energy Sources ; China University of Geosciences ; Beijing 100083 ; China) ; Wu Changzhi
- 刊名：Geological Bulletin of China
- 出版年：2010
- 卷期：29(6)
- 关键词：辉绿岩 ; diabase ; 氩—氩计时 ; Ar-Ar dating ; 岩石圈 ; lithosphere ; 地壳减薄 ; crustal thinning ; 华北地区 ; North China
- 页码：p.842-850
- 图表：8 illus., 2 tables, 67 refs.
- 分类号：0801
- issnNo：ISSN1671-2552
- isbnNo：CN11-4648/P
摘要
Ar-Ar dating for whole rock from the Qinglongtai diabase returns a plateau age of 35.5±1.7 Ma, which is in good accordance with their isochronal age within the uncertainty. It shows that the diabase has intruded in the Paleogene Shahejie period.Geo-chemically, these diabases have low SiO2, high Na2O+K2O and TiO2 contents, with intensive differentiation between light REE and height REE, slight Eu positive anomaly, and generally enrich in large iron lithophile elements (LILE, such as Sr and Ba) and high field strength elements (HFSE, such Nb and Ta), and can be comparable to those typical ocean island basalts (OIB).