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通过野外地质考察和地震资料解释,将龙门山褶皱冲断带划分为5个构造带,即青川-茂汶断裂以西为松潘-甘孜构造带,青川-茂汶断裂与北川-映秀断裂之间为韧性变形带,北川-映秀断裂与马角坝-通济场-双石断裂之间为基底卷入冲断带,马角坝-通济场-双石断裂与广元-关口-大邑断裂之间为前缘-褶皱冲断带,广元-关口-大邑断裂以东为前陆坳陷带,在构造变形特征上,各条断裂在演化上具有前展式特征,在松潘-甘孜构造带和韧性变形带构造变形强烈,形成推覆构造带等构造变形样式,在前缘-褶皱冲断带和前陆坳陷带,变形强度较弱,形成背冲断块或断层相关褶皱等构造,西北部区域的变形表现为塑性变形特征,向南东方向渐变为塑-脆性变形和脆性变形,在剖面上各条断裂所形成的深度向盆地方向逐渐递减。龙门山褶皱冲断带的分带性变形特征是由多种因素共同影响的结果,这些因素主要有板块构造背景的决定作用、多套滑脱层的控制作用和岩性因素的制约作用。
Through field geologic investigation and seismic data interpretation, the Longmen Shan fold-thrust belt is divided into five tectonic belts, that is, the Songpan-Garze zone to the west of the Qingchuan-Mauwen fault and between the Qingchuan-Mauwen fault and the Beichuan-Yingxiu fault Ductile deformation zone, the Beichuan-Yingxiu fault and the Majiaba-Tongji-Jiashi-Shuangshi fault are the basal inrush-thrust belt, the fault zone between the Majiaba-Tongji-Jiashi-Shuangshi fault and the Guangyuan-Guankou-Dayi fault The frontal-fold-thrust belt and the east of the Guangyuan-Guankou-Dayi fault are the foreland depression belt. On the tectonic deformation characteristics, the faults have the evolvement of pre-expansive features. In the Songpan-Garzê structural belt and the toughness Deformation belt tectonic deformation is strong, the formation of nappe belt and other tectonic deformation patterns in the leading edge - fold thrust belt and foreland depression zone, the deformation strength is weak, forming back-thrust fault or fault-related fold structure, the northwest The deformation of the area is characterized by plastic deformation, which changes gradually to plastic-brittle and brittle deformation in the south-east direction. The depth of each fault in the section gradually decreases toward the basin. The zonal deformation characteristics of the Longmen Shan fold-thrust belt are the result of a combination of factors that are mainly determined by the tectonic setting of the plate tectonics, the control of multiple sets of landslides and the constraints of lithological factors.