摘要
辽吉硼矿带是世界级非金属成矿省,但其成矿时代研究薄弱,成因类型和构造环境认识分歧。本文报道新获得的后仙峪超大型硼镁矿床金云母^(40)Ar-^(39)Ar年龄,并厘定成矿时代。主矿体金云母氩-氩坪年龄为884.4±8.9Ma(MSWD=0.47),正、反等时线年龄分别为885.0±7.5 Ma(MSWD=0.55)和885.8±7.3 Ma(MSWD=0.79),表明主成矿事件发生在885Ma左右,可能与Rodinia超大陆汇聚事件有关。矿体与闪长岩脉接触带蚀变岩的金云母氩-氩坪年龄为386.5±3.9Ma(MSWD=1.4),正、反等时线年龄分别为386.7±5.3 Ma(MSWD=2.6)和387.1±7.2 Ma(MSWD=3.9),代表成矿后局部改造事件的年龄,后期改造与早泥盆世岩浆作用有关。
The Liao-Ji giant boron belt is a world-class non-metallic ore province,but its metallogenic time has not been well constrained yet.The metallogenic type and tectonic setting of the Liao-Ji boron belt are still controversial.In this paper we present new ^(40) Ar-^(39) Ar phlogopite ages for the Houxianyu Boron deposit to time the boron mineralization.Phlogopite grains separated from the major ore-body yield ^(40) Ar/^(39) Ar plateau age of 884.4±8.9Ma(MSWD=0.47),isochron age of 885.0±7.5Ma(MSWD=0.55) and an...
出处
《岩石学报》
SCIE
EI
CAS
CSCD
北大核心
2009年第11期2752-2762,共11页
Acta Petrologica Sinica
基金
国家973项目(2006CB403500和2007CB815600)
自然科学基金项目(编号40352003和40425006)资助
关键词
氩-氩年龄
后仙峪硼矿床
辽吉硼矿带
辽河群
华北克拉通
^（40）Ar-^（39）Ar age
Houxianyu boron deposit
Liao-Ji boron belt
Liaohe Group
North China Craton
