摘要
小长山南超单元花岗岩是新疆北山构造带中重要的地质体 ,为华力西中期第 2序次岩浆侵入活动的产物 ,包括 5个单元 ,出露面积 132 .9km2 ,其中第 4单元同位素地质年龄 32 0 .2Ma±2 3Ma(锆石 ,Pb -Pb法 )。岩石系列属钙碱性 ,为明显同源岩浆演化序列 ,微量元素指示其具大陆弧背景下成熟弧花岗岩和I型花岗岩特征。
The southern Xiaochangshan granitic intrusive is an important geological body in Beishan tectonic belt, Xinjiang, produced by the second sequence magmatic intrusion in the middle Hercynian period. The superunit is composed of five units covering an area of about 132.9 km 2. The isotopic geological age of the fourth unit is 320.2±23 Ma (zircon, lead_lead age method). The rocks are of calc_alkaline series and belong obviously to the comagmatic evolutionary sequence. Trace elements show characteristics of the mature arc granite in the background of the land arc and I_type granite. The superunit was formed by the strong magmatic intrusion during the closing period of Beishan craton rift valley.
出处
《岩石矿物学杂志》
CAS
CSCD
北大核心
2002年第2期162-168,共7页
Acta Petrologica et Mineralogica
关键词
北山构造带
裂谷
花岗岩超单元
成熟弧
闭合期
Beishan tectonic belt
rift valley
granite super unit
the mature arc
closing period
