LACUSTRINE CARBONATE SOURCE ROCKS AND THEIR ORGANIC GEOCHEMICAL CHARACTERISTICS——TAKING THE TERTIARY SYSTEM OF QAIDAM BASIN FOR EXAMPLE

The characteristics of lacustrine carbonate type source rocks are thai in the rorks the content of carbonate is high,the content of organic carbon is low.but the transformation ratio of their organic material to soluble hydrocarbons is higher. The distributive character istics of biomarkers in their soluble extracts are very similar to those in carbonate rocks and evaporite rocks series.