Based on the statistical analysis of the geochemical data of more than 192 rock samples collected from 6 basins in China

the author has come to the following conclusions:1.The parameters 17α21β-Hopane-22

S

/22

R

17α21β-Hopane/17β21α-Moretane and 5α14α17αC

29

-Sterane-20

S

/(20

R

+20

S

)are available maturity indices of source rocks.2.The sterane ratio 5α14α17αC

27

/5α14α17αC

29

is a better index of kerogen types.3.Some parameters

as Pristane/n-C

17

Phytane/n-C

18

are of little practical value.