详细信息   

• 责任者：Li Jianfeng (Key Laboratory of Orogenic Belts and Crustal Evolution ; MOE ; School of Earth and Space Sciences ; Peking University ; Beijing 100871 ; China) ; Tang Wenhao
• 刊名：Chinese Journal of Geophysics
• 出版年：2010
• 卷期：53(12)
• 关键词：裂变径迹计时 ; fission-track dating ; 侏罗纪 ; Jurassic ; 北京 ; Beijing
• 页码：p.2907-2917
• 图表：5 illus., 1 table, 35 refs.
• 分类号：1200
• issnNo：ISSN0001-5733
• isbnNo：CN11-2074/P

摘要

Apatite fission track analysis is made to reconstruct the tectonic-thermal history of Jurassic basin at Qianjiadian area, Beijing. AFT ages of the three samples located at upper Houcheng Formation are concentrated in 85.7～76.0 Ma, smaller than corresponding stratigraphic age; the mean confined track length is 9.4～10.8 μm, smaller than the initial confined track length (16.3±0.9 μm), showing a single peak state of skewed length distribution, and the standard deviation is 2.1～2.5; AFT ages of the three samples located at lower Houcheng Formation are concentrated in 82.6～62.4 Ma, also smaller than corresponding stratigraphic age; the mean confined track length is only 7.2～7.7 μm, far shorter than the initial track length (16.3±0.9 μm), where the length of the mean confined track of YQ-07 shows proximal bimodal distribution, with the standard deviation of 3.1. Clearly, these six samples experienced moderate annealing, and the maximum temperature may be close to 90 ℃.