supported by the National Natural Science Foundation of China(No.40572081);the Chinese Academy of Sciences(No.KZCX1-SW-18)
Four samples from a Permian reservoir in the Ordos Basin of North China were separated into twelve fractions in grain sizes of 〈0.5, 0.5-1 and 1-2 μm. Using the ^40Ar-^39Ar step-heating method, all of the fractions ...