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通过对构造事件形成的产物 (岩浆岩、各种矿物等 )进行氩 -氩年龄测定、裂变径迹年龄测定、ESR年龄测定和计算机模拟 ,得出龙门山造山带 -川西前陆盆地系统自印支期以来 ,共发生了 7次构造事件 :(1)卡尼期末的构造事件 (D1 ) ,形成 S1 和 F1 ,并有区域低温动热变质作用 ;(2 )诺利期末的构造事件 (安县运动 ,D2 ) ,产生川西前陆盆地上三叠统须四段与下伏地层不整合接触和须四段砾岩的分布 ,并有较强的岩浆作用 ;(3)燕山期 (12 0～ 130 Ma,D3) ,有较强的岩浆作用和变质作用 ;(4 )喜马拉雅期 6 0 Ma左右的构造事件 (D4) ;(5 )喜马拉雅期 30～ 40Ma的构造事件 (D5 ) ;(6 )喜马拉雅期 2 0～ 2 5 Ma的构造事件 (D6 ) ;(7)喜马拉雅期 10 Ma的构造事件 (D7)。后 4次构造事件使龙门山造山带 -川西前陆盆地系统发生强烈的冲断作用和隆升作用
Argon-argon dating, fission track dating, ESR dating and computer simulation of the products formed from the tectonic events (magmatic rocks, various minerals, etc.) show that the Longmenshan orogenic belt - There are altogether seven tectonic events since the epoch: (1) tectonic event (D1) at the end of Carney period, forming S1 and F1, and regional thermo-thermal metamorphism; (2) (D2), resulting in the unconformity contact of the Upper Triassic Xu 4 member with the underlying strata and the distribution of the Ju-Si conglomerate in the western Sichuan foreland basin with strong magmatic activity; (3) Yanshanian period (12 0-130 Ma , D3), with strong magmatic activity and metamorphism; (4) tectonic event (D4) of about 60 Ma in the Himalayan period; (5) tectonic event (D5) of 30-40 Ma in the Himalayan period; Tectonic event (D6) of 20-25 Ma; (7) Structural event of 10 Ma in the Himalayan period (D7). After the 4th tectonic event, strong thrusting and uplifting occurred in the Longmenshan orogenic belt-western Sichuan foreland basin system