The role of fossil diatom study in paleolimnology is to analogize the ancient lakes, reconstruct their lake envirnmental evolution histories and find out lake function and lake variation regularities based upon the distribution, ecology and environmental condition of living diatom flora in modern lakes, and upon some other organic and inorganic indicators and dating data as well.

The distribution of the Neogene lacustrine sediment beds and development of the Bohai paleolake are discussed, based on the analysis of the particulate sedimentary matter from 5 wells in the Bohai Bay.

The characteristics of source rocks in the Member 3 of Shahejie Formation in Dongying Depression revealed the obvious fluctuation of the sedimentary course of lake.

Correlation between carbon and oxygen isotopic ratios of lacustrine carbonates and types of oil-producing paleolakes;