Abstract:

（UˉTh）/He dating of apatite and zircon is performed on eleven core and outcrop samples from the PuguangˉMaoba and Tongjiang areas in northeastern Sichuan Basin and the results are used to establish a dyˉnam ic evolution pattern forHe age and depth/temperature.The closure temperature of the He in apatite in this area is at85℃.The drilling core samples experienced the same thermal evolution historywith the outcrop samˉples in the northeastern Sichuan Basin，where the Tertiary and theQuaternarywere themain periods of cooling，uplifting and denudation.During these periods，the denudation rate was about74.8-172.5m/Ma，the maxiˉmum denudation thicknesswas2800-3000m，the earth temperature gradually reduced to helium closure temˉperature of apatite，and finally to the current temperature.All these were related to the reaction of the Sichuan

Key words: （UˉTh）/He age, closure temperature, uplift and denudation, dynam ic evolution of thermal history, thermal history simulation, marine sequence in South China