摘要
根据火山岩样品的Rb Sr同位素分析结果 ,得到北京延庆白河堡地区后城组的Rb Sr等时线年龄为 1 6 2 8Ma ,误差为± 1 1 4Ma ( 1σ) ,或± 36 1Ma( 95%置信区间 ) ,M S W D 等于 2 98。结合其上下层位关系 ,白河堡地区后城组的时代可能属于中侏罗世Bathonian阶。
According to the Rb-Sr isotopic analysis of volcanic rock samples of the Houcheng Formation in Baihepu area of Yanqing County,Beijing Municipality,the Rb-Sr isochron age of 162 8Ma with the error of±11 4Ma(1σ) or±36 1Ma(95% confidence level)(M S W D =298) was obtained.Based on the regional stratigraphic relation,the age of Houcheng Formation maybe belong to Bathonian Stage of Middle Jurassic Epoch.It is suggested that the Houcheng Formation in Baihepu area of Yanqing County might be correlated with Tiaojishan Formation.
出处
《北京地质》
2003年第4期1-5,共5页
Beijing Geology
基金
国家自然科学基金项目 (编号 4 0 10 4 0 0 3)
中国博士后科学基金
中国科学院王宽诚博士后工作奖励基金
中国地质调查局地质调查项目 (K1 4 1 2 )联合资助
关键词
Rb-Sb等时线年龄
火山岩
后城组
白河堡
北京
Rb-Sr isochron age
volcanic rocks
Houcheng Formation
Baihepu
Yanqing County
Beijing
