Study on thermal history and oil-generated environment from well CC1

U-Pb isotope geochronological study of core samples implies that the sedimentary strata are derived from North-China ancient land and the age of the hidden granite derived from the remelted Archean rocks with lower crust signature is 99 Ma. Fluid inclusion investigation indicates that the Ordovician carbonate rocks are rich in organic matters and should be a better set of oil-generated rocks and reservoir. Based on fission track analysis of apatites from different depths and the paleo-geothermal variation, the authors suggest that there be at least three oil-generated stages. The range of annealing belt of apatite tracks and the paleo-geothermal gradient in this well are 1700-3900 m (roughly corresponding to oil-generated belt) and 3.1 degree C/100 m respectively after Tertiary sedimentation