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对川东北普光-毛坝地区和通江地区的11个岩心和露头样品进行锆石、磷灰石(U-Th)/He定年分析,初步建立了He年龄-深度/温度动态演化模式,该地区磷灰石He封闭温度为85℃。川东北钻井岩心和剖面样品经历相同的热演化历程。该地区第三纪至第四纪为冷却抬升剥蚀主要时期,剥蚀速率约为74.8～172.5m/Ma,剥蚀厚度大约为2 800～3 000 m,地温逐渐降低到磷灰石He封闭温度,直至达到现今温度,与青藏高原隆升引发的新构造运动在四川盆地的响应有关。普光5井等3 200 m以上中生界样品未经历过锆石He封闭温度,可能只有3 200 m以下的样品经历锆石He封闭温度,但所有样品都经历了磷灰石He封闭温度。根据锆石(U-Th)/He年龄大致推算出,川东北地区可能在晚侏罗世开始抬升,在晚侏罗世—早白垩世期间普光-毛坝地区和通江地区都处于缓慢抬升剥蚀阶段,只是普光-毛坝地区抬升剥蚀开始时间要早于通江地区。磷灰石和锆石He封闭温度和年龄揭示了该区动态热演化历史。该区在178.0 Ma之前古地温大于170～190℃,随后地层继续抬升,古地温下降;在40.5～178.0 Ma时,古地温为85～170℃;在0～40.5 Ma时,现今地温小于85℃。
Zircon and apatite (U-Th) / He dating of 11 core and outcrop samples from the Puguang-Maoba area and Tongjiang area in northeastern Sichuan Province were preliminary analyzed to establish the He age-depth / temperature dynamic evolution model Region apatite He sealing temperature 85 ℃. Northeast China drilling core and profile samples undergo the same thermal history. The Tertiary to Quaternary in this area are the main period of cooling, uplifting and denudation. The ablation rate is about 74.8 ~ 172.5m / Ma and the ablation thickness is about 2 800 ~ 3 000 m. The ground temperature is gradually reduced to apatite He sealing temperature The temperature reached today is related to the response of neotectonic movement triggered by the uplift of the Qinghai-Tibet Plateau in the Sichuan Basin. The samples above 3 200 m in the Puguang 5 well, such as those above 3 200 m, have not undergone the closure temperature of zircon He, and only samples below 3 200 m may have undergone the closure temperature of zircon He, but all the samples have experienced apatite He closure temperature. Based on the U-Th / He ages, it is estimated that the northeastern Sichuan area may have started uplift in the Late Jurassic and slowly uplifted in the Puguang-Maoba area and the Tongjiang area during the Late Jurassic-Early Cretaceous Denudation stage, but the Puguang-Mao dam area uplift erosion earlier than the Tongjiang area. Apatite and zircon He closure temperature and age reveal the history of dynamic thermal evolution in this area. The paleo-geothermal temperature was higher than 170-190 ℃ before 178.0 Ma, and then the strata continued to rise. The paleo-earth temperature dropped. From 40.5 to 178.0 Ma, the paleotemperature was 85-170 ℃. At 0-40.5 Ma, the present temperature was less than 85 ℃ .