摘要
分析研究认为,中灶火地区分布的鄂拉山组火山岩为中酸性、亚碱性之钙碱性系列高钾低钛型的火山岩;火山岩的稀土元素总量变化较大(139.45×10-6~219.55×10-6),轻稀土元素相对富集(LREE/HREE在7.695~13.46之间,平均为9.09),稀土元素配分曲线均呈现右倾较缓的平滑线.δEu值在0.53~0.83之间,具有弱负Eu异常;岩石微量元素配分图中曲线型式基本一致,反映了该区火山岩的同源性.通过构造环境分析认为,区内鄂拉山组火山岩形成于挤压碰撞作用形成的岩浆弧.
Study on the volcanic rocks from Elashan Formation in Zhong Juh area,Qinghai Province,indicates that it belongs to acid-intermediate high-K and low-Ti calc-alkali series. The analysis results reveal that ∑ REE varies from139.45×10-6 to 219.55×10-6,with enrichment of LREEs（LREE/HREE of 7.695-13.46,averagely 9.09）. The distribution patterns show gently right-dipping smooth curves with weak negative Eu anomaly（δEu =0.53-0.83）. The general uniformity of trace element curve patterns reflects the homogeneity of volcanic rocks in this area. According to the analysis on tectonic environment,it is concluded that the volcanic rocks is the product of magmatic arc formed by compression and collision.
作者
赵明福
史连昌
李成福
魏有宁
李玉龙
ZHAO Ming-fu, SHI Lian-chang, LI Cheng-fu, WEI You-ning, LI Yu-long(1. Qinghai Bureau of Geological Survey, Xining 810000, China; 2. College of Earth Sciences, Jilin University, Changchun 130061, Chin)
出处
《地质与资源》
CAS
2018年第2期117-123,共7页
Geology and Resources
基金
青海省地质勘查基金项目"青海省昆仑河地区1:5万矿调多元地质信息集成与找矿预测"(编号2016020021jc021)
关键词
鄂拉山组火山岩
地球化学特征
构造环境
中灶火地区
青海省
volcanic rock of Elashan Formation
geochemical characteristics
tectonic environment
Zhong Juh area
Qinghai Province
