摘要
通过对甘肃省白银市乌金峡一带中酸性侵入体的地质学、岩石化学、地球化学等研究，发现该侵人体高w（Na2O），低w（MgO）、w（TFeO）、w（Al2O3）、w（K2O），w（TiO2）、w（MgO）、w（MnO）、W（TFeO）、w（CaO）、w（K20）与w（SiO2）负相关，w（Na2O）与w（SiO2）正相关；轻、重稀土都有分异，但轻稀土更明显，且轻稀土富集，8（Eu）轻度正异常一亏损，大离子亲石元素Ba、Th、Sr富集，Rb、Li亏损，属同源岩浆演化的产物。岩浆结晶温度为700℃～890℃。形成时代大致为奥陶纪中晚期，属干岛弧构措环境，为中祁谇地块和北祁连洋间相互作用的结果。
Through the geological, petrochemical and geochemical research on intermediate acid intrusive rock located in Wujinxia area of Baiyin City in Gansu Province, it is found that w（Na2 O） are high, meanwhile, w（MgO）, w（TFeO）, w（ Al2O3 ） and w（ K2 O） are low, w（TiO2 ）, w（MgO）, w（MnO）, w（TFeO）, w（CaO）, w（ K2 O） and w（ SiO2 ） are negative correlated, w（Na2O） and w（SiO2 ） are positive correlated, LREE and HREE are differentiated, LREEs are more obviously enriched, and 8（Eu） are depleted, large ion lithophile elements such as Ba, Th, Sr are enriched, Rb and Li are poor. The temperature of magmatic crystallization is from 700 ℃ to 890 ℃. The intrusinve body was the product of comagmatic evolution during the mutual interaction of Central Qilian massif and Qilian ocean in the island are tectonic environment of middle-to later Ordovician period.
出处
《地球科学与环境学报》
CAS
2008年第3期240-248,277,共10页
Journal of Earth Sciences and Environment
关键词
白银市
乌金峡
中酸性侵入体
中祁连
地质特征
构造意义
岩石地球化学
甘肃
Wujinxia area
gaiyin City
intermediate-acid intrusive
Central Qilian massif
geological characteristic
tectonic significance
geochemistry rock
Gansu Province
