岩石矿物学杂志2001，Vol.20Issue(2)：123-133,11.
北京西山髫髻山组火山岩的地球化学特征与岩浆起源
Geochemical Features and Origin of Volcanic Rocks of Tiaojishan Formation in Western Hills of Beijing
李伍平 1章大港 2路凤香 3李献华 4周瑶琪 2孙善平 5李家振5
作者信息
- 1. 长安大学地球科系,中国科学院广州地球化学研究所,
- 2. 石油大学油气资源与环境地质研究所,
- 3. 中国地质大学地球科学学院,
- 4. 中国科学院广州地球化学研究所,
- 5. 中国地质大学地质系,
- 折叠
摘要
Abstract
Tiaojishan Formation in Western Hills of Beijing was dated at Late Jurassic based on the Ar-Ar ages for tachyandesites (all plateau ages and isochrone ages of plagioclase are respectively 148.91±2.98 Ma and 146.60±2.93 Ma). Geochemistry of elements and isotopes show that volcanic rocks of Tiaojishan Formation are mainly of high-K calc-alkaline series characterized by indistinct Eu anomaly, relative enrichment of large-ion lithophile elements such as.Rb, Sr and Ba, relative depletion of high field-strength elements (e.g. Nb, Ta, Ti, Zr, Hf ), and low Nd, Sr and Pb ratios, suggesting the features of island -arc and active continental margin and enriched mantle. The authors think that volcanic rocks of Tiaojishan Formation were derived from partial melting of old-age (Archean) basaltic rocks of the lower crust and the crust-mantle transitive zone by the underplating of basaltic magma during intrcontinental orogeny. 关键词
髫髻山组/下地壳-壳幔过渡带/玄武质岩石/晚侏罗世/陆内造山带/北京西山分类
天文与地球科学引用本文复制引用
李伍平,章大港,路凤香,李献华,周瑶琪,孙善平,李家振..北京西山髫髻山组火山岩的地球化学特征与岩浆起源[J].岩石矿物学杂志,2001,20(2):123-133,11.
