地球学报2001，Vol.22Issue(1)：55-60,6.
岚皋早古生代碱质煌斑杂岩地球化学特征及成因探讨
Geochemical Characteristics and Petrogenesis of the Early
Paleozoic Alkali Lamprophyre Complex from Langao County
徐学义 1夏林圻 1夏祖春 1黄月华2
作者信息
- 1. 中国地质调查局西安地质矿产研究所
- 2. 西北大学地质系,
- 折叠
摘要
Abstract
The alkali lamprophyre complex from Langao County, whose chondrite-normalized REE patterns all incline to the right and whose major elements vary regularly, has abundant incompatible elements. Studies on major and trace elements indicate that there existed two parallel fractional crystallization trends during the evolution of primary magma which suffered insignificant contamination of crustal material. The enrichment of LREE and incompatible elements with the change of Zr/Nb, Ce/Y, Dy/Yb, La/Yb and Zr/Sm ratios show that the lamprophyre magma couldn't have been derived from partial melting of spinel-, garnet-lherzolite mantle source or amphibole-bearing spinel or garnet lherzolite mantle source. Sr-Nd-Pb isotope variations indicate that the source of lamprophyre magma was mainly composed of HIMU mantle. The mantle plume not only played an important role in the formation of lamporphyre, but also controlled the metasomatism that occurred in the source of the alkali lamprophyre complex.关键词
煌斑杂岩/地球化学/成因/岚皋分类
天文与地球科学引用本文复制引用
徐学义,夏林圻,夏祖春,黄月华..岚皋早古生代碱质煌斑杂岩地球化学特征及成因探讨[J].地球学报,2001,22(1):55-60,6.
