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利用镜质组反射率和磷灰石与锆石的(U-Th)/He年龄一起模拟了川东北地区三叠纪以来的构造-热演化特征。结果表明早三叠世的热流值在51～66mW/m2,自晚三叠世至白垩纪随盆地性质由前陆盆地演化为陆内坳陷盆地,热流缓慢降低直至现今的44.5mW/m2。但在晚白垩世—古新世时期受燕山晚期构造运动的影响,热流有一个微弱增高的现象。同时,磷灰石和锆石的He年龄揭示了川东北地区大致在晚白垩世期间开始隆升且抬升剥蚀量较大。因此,磷灰石和锆石的(U-Th)/He年龄可以揭示后期详细的冷却历史。
The vitrinite reflectance and the apatite and zircon U-Th / He ages are used to simulate the tectono-thermal evolution of the northeastern Sichuan area since Triassic. The results show that the value of heat flow in the Early Triassic ranges from 51 to 66 mW / m2. From Late Triassic to Cretaceous, the basin properties evolve from the foreland basin to intracontinental depression basin, and the heat flow slowly decreases to 44.5 mW / m2 today. However, due to the late Yanshanian tectonic movement during the Late Cretaceous-Paleocene period, there was a slight increase in heat flux. In the meantime, He ages of apatite and zircon reveal that the northeastern Sichuan area started to uplift during the Late Cretaceous and had a large amount of uplifted and denudated sediments. Therefore, the (U-Th) / He ages of apatite and zircon can reveal the detailed cooling history of the later period.