【摘要】 5.12汶川8级大地震表明龙门山断裂带仍然是一个构造活动带,为了达到防震减灾的目的,对其进行深入研究是很有必要的。通过龙门山北段毛坝—竹园坝实测构造地质剖面,分析野外实测构造的变形特征,根据变形强弱差异,将毛坝—竹园坝之间分为4个构造变形带,并总结各个构造带的变形特征以及变形序列。在野外研究基础上,首次提出竹园坝断裂,并指出竹园坝断裂是龙门山前山带的主干断裂之一,是喜马拉雅山运动的直接结果。最后,再结合前人资料讨论龙门山北段的构造演化。更多还原

【Abstract】 The MS8.0 huge earthquake of May 12th,2008 occurred at Wenchuan shows that Longmen Mountains situate in an active tectonic zone.In order to achieve the aim of defending earthquakes and reducing disasters,further research on Longmen Mountains is very important.Through analyses of tectonic kinematics and dynamics observed in the northern segment section of Longmen Mountains,4 tectonic deformation bands are divided between Maoba and Zhuyuanba.After summing up the deformation characteristics of the 4 tectonic bands,their evolution histories are discussed on the basis of previous literature.Based on the results,Zhuyuanba Fault is first discussed,and it is one of the main faults in Longmen Mountains and a direct result of Himalayan movement.Finally,combined with previous studies,the evolution of Longmen Mountains is discussed.The main deformations studied in this paper occurred between Indo-Chinese movement and Himalayan movement.It experienced the drape orogenic movement in indosinian movement,and the rudiment was formed.The Middle Faults moved again during Yanshan movement.Then some concealed faults were formed.Himalayan movement is a representative of the thrust nappe orogenic movement in Longmen Mountains.The strong extrusion happened and the Middle Faults moved again at that time.Many faults which cut off the anticlines and synclines and small closed folds came into being then.更多还原