四川盆地震旦系—下古生界烃源岩处于高过成熟度阶段，其R_o一般为2.36%~3.39%。根据埋藏史及古地温梯度，应用改进了的Karweil方法，将该烃源岩划分成4个演化阶段，并依据高科1井、盘1井和五科1井等重点井进行系统成熟度模拟，使之与实测的成熟度值一致，结果表明四川盆地西南部坳陷震旦系—下古生界烃源岩生烃最早，东部地区次之，乐山—龙女寺古隆起最晚，具体情况是:高科1井下寒武统烃源岩主生油期在中侏罗世，主生气期在晚侏罗世—早白垩世，盘1井下寒武统烃源岩主生油期在二叠纪，主生气期在晚三叠世；五科1井下寒武统烃源岩主生油期在早三叠世，主生气期在早中侏罗世；盘1井志留系烃源岩主生油期在晚三叠世，主生气期在中侏罗世，五科1井志留系烃源岩主生油期在早侏罗世，主生气期在晚侏罗世。

The Sinian\|Lower Palaeozic source rock in Sichuan basin is high/over mature, with maturity 2.36%~3.39%. Based on the improving Karweil, burial history and paleogeothermal gradient, the evolution history of source rock can be divided into four phases. We simulate the maturitys to GK1, PAN1 and WK1, etc, which equal to the mesured maturitys. Sinian-Lower Palaeozic source rock produce oil & gas earliest in the southwest depression, and then the eastern area inSichuan basin, Leshan-Longnvsi paleouplift latest. The lower Cambrian source rock of GK1 well mainly procuce oil in J₂, and mainly produce gas in J-3-K-1; The mainly producing oil period of Pan1 well is Permian, the mainly producinggas period is T; The mainly producing oil period of WK1 well is T₁, the mainly producing gas period is J₁-J₂. With regard to Silurian source rock, The mainly producing oil period of P1 well is T₃, the mainly producinggas period is J₂; The mainly producing oil period of WK1 well is J₁, the mainly producing gas period is J₃.Sichuan basin;Sinian-Lower Palaeozic; High/over mature;Source rock;Karweil.