大兴安岭托河林场毕利亚山碱长花岗岩黑云母地球化学特征及地质意义  

Geochemical characteristics and geological significance of biotites from Bileashan alkali-feldspar granite of Tuohe forest farm in Da Hinggan mountains

作　　者：晋瑞香 孙国胜[1] 冯泓达 何欣[1] 王刚 赵天雪 刘承先[1] 

机构地区：[1]吉林大学地球科学学院,长春130061 [2]武警黄金部队第一支队,黑龙江牡丹江157000

出　　处：《世界地质》2017年第3期726-733,共8页World Geology

基　　金：内蒙古地勘基金项目(NMKD2014-38)

摘　　要：根据大兴安岭毕利亚山碱长花岗岩黑云母的电子探针(EPMA)测试结果,对黑云母的化学成分特征、成因类型及结晶时的温度和氧逸度进行了研究,并探讨岩浆源区的性质及成岩背景。毕利亚山碱长花岗岩黑云母具有高Si(SiO_2:39.876%~42.419%)、富Mg(MgO:18.138%~20.02%)、贫Fe(FeO^t:10.549%~11.468%)特征,属镁质黑云母;黑云母的结晶温度为590℃~650℃,且具有较高的氧逸度。其∑Al的值为1.01~1.044,Fe/(Mg+Fe)的值为0.228~0.262。Mg/(Mg+Fe^(2+)+Mn)的值为0.673~0.834,FeO^t/(FeO^t+MgO)的值为0.345~0.387,指示了其岩浆源区为富镁的岩石圈地幔,并且在岩浆演化过程中发生混染作用。Based on the electron microprobe（ EPMA） of biotites from Bileashan alkali-feldspar granite in the Da Hinggan mountains,the authors studied the chemical composition,genetic types,formation temperature and oxygen fugacity of biotites and discussed the characteristics and diagenetic background of magma sources. The studied biotites are characterized by high Si O2（39. 876% ~ 42. 419%） and Mg（18. 138% ~ 20. 02%）,low FeO^t（10. 549% ~ 11. 468%）,which belongs to Mg-biotites. The crystallization temperature of biotites ranges from590℃ to 650℃,with high oxygen fugacity. Total Al ranges from 1. 01 to 1. 044 and Fe/（ Mg ＋ Fe） varies from0. 228 to 0. 262,with Mg/（ Mg ＋ Fe^（2 ＋）＋ Mn） and FeOt/（ FeOt＋ MgO） in the ranges of 0. 673 to 0. 834 and0. 345 to 0. 387,respectively,suggesting magma source of Mg-riched lithospheric mantle,with contamination during the magma evolution.

关 键 词：黑云母 碱长花岗岩 成岩背景 大兴安岭 

分 类 号：P595[天文地球—地球化学]