摘要
以新疆西准噶尔玛依拉山-萨雷诺海蛇绿岩为重点进行讨论.该区出露的火成岩种类较多,表现出构造混杂特点.变质橄榄岩是具有一定亏损程度的地幔残体,LREE的富集主要是后期蚀变的结果.玄武岩的稀土分布型式是平坦型的或LREE略亏损型的.与MORB相比,REE的总量较高,高Fe和Ti,Mg值低,是一种演化的岩石,与东太平洋中隆地高Fe和Ti的铁质拉斑玄武岩成分相当,地球化学特征类似于MORB,可能形成于小洋盆环境.
This paper discussed mainly the ophiolite from Mayila-Saleinohai of West Jungger, where many types of igneous rocks outcropped, showing the feature of a tectonic melange. The metamorphic peridotite is considered as a relatively depleted mantle residuum with enriched LREE due to alteration. The basalt there shows a flat or little depleted LREE distribution pattern, comparing to MORB, with higher total REE content, high contents of Fe and Ti, and low Mg value. The composition of the basalt is much comparable to the ferruginous tholeiite found in the median ridge of East Pacific Ocean. The geochemical features indicated that the basalt probably formed in a small ocean basin background.
出处
《新疆地质》
CAS
CSCD
2004年第3期290-295,共6页
Xinjiang Geology
