地质科学2013，Vol.48Issue(2)：515-531,17.DOI:10.3969/j.issn.0563-5020.2013.02.013
龙门山断裂带变形特征
Deformational characteristics of the Longmenshan fault zone
摘要
Abstract
Field structure and stress field analyses indicate that the Longmenshan fault zone was in NW-SE compressive stress field in early Cenozoic, developing the NNE-trending sinistral strike-slip structural system, which was superimposed and reformed by the late Longmenshan fault zone characterized by dextral transpressional deformation. Since the superimposition and reformation, the Longmenshan fault zone has been in the E-W compressive stress field, contributing to the seismic structure. Detrital apatite fission track analysis of the fluvial sands shows remarkable discrepancy in the displacement along the trend direction in the Longmenshan fault zone, with a trend of normal distribution. According to the monotonic thermal history responding to the uplift and cooling, we speculate the transformation time of the two stages of deformation to be around 40 Ma. Based on the stratigraphic thickness and the deformation-depth model, the Longmenshan fault zone is considered to be a large strike-slip fault zone, extending tens of kilometers wide, which shows flower-structural feature on the cross section. The near-surface thrust structure is thin-skinned structure, and we establish a depth-deformation model in Longmenshan fault zone.关键词
龙门山断裂带/热史/构造应力场/地震/走滑构造Key words
Longmenshan,Thermal history, Stress field,Earthquake,Strike-slip fault zone分类
天文与地球科学引用本文复制引用
刘志成,季建清,涂继耀,鄢雪龙,唐俊杰..龙门山断裂带变形特征[J].地质科学,2013,48(2):515-531,17.基金项目
北京大学地质学本科生科研基金、中国地质调查局地质调查项目(编号:12120113013700)和岩石圈演化国家重点实验室自主研究项目(编号:专1102)资助. （编号:12120113013700）
