The differences of hydrocarbon-generating conditions of lacustrine and marine carbonate source rocks were discussed in various aspects

such as the distribution characteristics

sedimentary environment

rock type

organic geochemical characteristics and hydrocarbon generation mode.The results show that marine and lacustrine carbonate source rocks all containe varying amounts of argillaceous components and are dominated by kerogen of typeⅠor type Ⅱ.In addition

there is no significant difference in occurrence of their organic matter

except for that lacustrine carbonate source rocks contain more amorphous organic matters.Organic carbon content of marine carbonate rocks is generally low

while that of lacustrine carbonate rocks is highly variable.The research of the hydrocarbon generation mode of lacustrine carbonate source rocks is still very weak in comparison with the marine carbonate source rocks

and the secondary hydrocarbon generation of the former should not be neglected.The formation conditions of lacustrine carbonate source rocks are controlled by many factors

the biogeochemical and sedimentological researches of lacustrine carbonate source rocks with high content of organic matters are especially important.Furthermore

the possibility of late hydrocarbon generation of lacustrine source rocks providing sufficient hydrocarbon sources for deep reservoirs of lacustrine faices is one of the important topics for future study.