摘要
根据^(40)Ar-^(39)Ar法和扩散理论,应用^(40)Ar-^(39)Ar阶段加热法测得河北迁安县蟒山花岗闪长岩-英云闪长岩岩体的HB-7、HB-8两个黑云母的坪年龄和相应的封闭温度分别为2059.4Ma、336℃和2072.9Ma、353℃。年龄值反映了黑云母冷却到其封闭温度至今所经历的时间。从2500Ma至2000Ma,岩体抬升速率为28m/Ma,冷却速率为0.8℃/Ma,表明该岩体在早元古代就是缓慢冷却的。
In the paper, using ^(40)Ar-^(39)Ar method and diffusion theory, the authors study isotopic geochronology and closure temperature of biotites from Mangshan granodiorite-tonalite of Qian'an county, Hebei Province.
HB-7 biotite and HB-8 biotite from the pluton after incremental heating gave two ^(40)Ar-^(39)Ar plateau ages of 2059.4Ma and 2072.9Ma, and their closure temperature are 336℃ and 353℃, respectively. The pluton has an uplift rate of 28m/Ma from 2500 Ma to 2000 Ma ago and a cooling rate of 0.8℃/Ma. These results show that the pluton slowly cooled during the early Proterozoic.
出处
《岩石学报》
SCIE
EI
CAS
CSCD
北大核心
1992年第4期332-340,共9页
Acta Petrologica Sinica
关键词
蟒山
黑云母
年龄
温度
Biotite
^(40)Ar-^(39)Ar age
Closure temperature
Mangshan granodiorite-tonalite
Hebei
