从裂变径迹分析探讨房山岩体地质热历史  

Thermal history of the Fangshan granodiorite intrusion, Beijing: Evidence from fission tracks of apatites and sphenes

作　　者：翟鹏济[1] 张峰[2] 赵云龙[3] 

机构地区：[1]中国科学院高能物理研究所,北京100080 [2]中国科学院地球化学研究所,贵州贵阳550002 [3]核工业北京地质研究院,北京100029

出　　处：《地球化学》2003年第2期188-192,共5页Geochimica

基　　金：中国科学院核分析技术开放研究实验室资助项目

摘　　要：测定了房山岩体内部相的花岗闪长岩中磷灰石和榍石的裂变径迹年龄和磷灰石自发和诱发裂变封闭径迹长度。根据磷灰石自发裂变封闭径迹平均长度和年龄对岩体热历史进行了模拟和探讨,长度分布模拟特征和参数与实测结果基本一致。并依据磷灰石和榍石裂变径迹年龄和封闭温度探讨了岩体的冷却和上升速度。Ages and confined induced and spontaneous fission track length in apatites and ages of sphene from the Fangshan granodiorite intrusion, Beijing are measured. The distribution of confined induced track length is narrow and symmetrical with a mean length of approximately 16.1 μ m and a standard deviation of around 0.7 μ m. The distribution of confined spontaneous track length become wide with an average of around 13.0 μ m and a standard deviation of approximately 1.8 μ m. The ages of apatites and sphenes are 45.3 Ma and 123.0 Ma, respectively. The thermal history is discussed by thermal model from confined spontaneous fission track length of 13.0 μ m and age of 45.3 Ma in apatites. Velocities of uplift and cooling are calculated by the ages of apatites and sphenes and their confined temperature.<P>

关 键 词：裂变径迹分析 磷灰石 榍石 长度分布 热历史 北京 花岗闪长岩 

分 类 号：P588.12[天文地球—岩石学] P597[天文地球—地质学]