In application of gas-chromatography and gas chrometography-mass spectrography

the authors studied fatty acids in 57 rock samples of the Cretaceous to the Neogene collected in well Fancan-1 in the Jianghan Basin. The carbonnumbers of monatomic fatty acids of the Jinghezhen Formation range from C

12

to C

30

while those of the Qianjiang Formtion range from C

9

to C

20

.The result shows that the fatty acids came from land organisms may be morethan those from marine organisms.