Abstract: Using the methods of mathematical geology, a criminant function is devel-oped for the thermal evolution of organics from Bayanhua group, based on geothermal logging data. Before the estimation of petroleum generation, a direct statistic prediction for the thermal evolution of organics can be made on the basis of statistical correlation of geothermal loggings and the thermal evolution of organics. The results of the prediction are fundamentally consistent with those from the estimation of petrolenm generation.