摘要
据1∶5万区域地质调查,大雁山岩体与上覆百足山组（K1b）呈不整合接触。对大雁山花岗闪长岩进行SHRIMP锆石U-Pb同位素定年,其谐和年龄为230.3±3.1 Ma（MSWD=3.1）,表明大雁山岩体为印支期岩浆活动的产物。岩体Al2O3含量为13.72%-14.35%,A/CNK为1.08-1.26,Rb/Sr为3.27-6.24,微量元素组成与南岭印支期花岗岩较为相似,为典型的陆壳改造型花岗岩类。研究认为,大雁山岩体形成于印支地块与华南地块拼合过程中的同碰撞构造环境,其成岩作用与碰撞过程中的加厚地壳物质的部分熔融有关。
According to 1∶50000 regional geological survey, contact relationship between Dayanshan pluton and the overlying Lower Cretaceous strata（K1b） is unconformity. The Concordia age of the SHRIMP zircon U-Pb dating of granodiorite from Dayanshan pluton is 230.3±3.1 Ma（MSWD=3.1）, and it shows that Dayanshan pluton is the product of Indonesian magmatism. Its Al2O3 is 13.72%-14.35%, A/CNK is1.08-1.26, Rb/Sr is 3.27-6.24, and trace element composition is similar to Nanling Indonesian granites. It is the typical crustal transformation type granite（S-type）. This research indicates that Dayanshan pluton was formed in the process of syn-collisional orogeny between Indonesian block and Southern China block, and its diagenesis was colsely related to the melting of thickened crustal material in the collision process.
出处
《矿物学报》
CAS
CSCD
北大核心
2016年第1期91-96,共6页
Acta Mineralogica Sinica
基金
中国地质调查局区域地质调查项目(编号:1212011220528)
