Abstract:

On the basis of the analysis of geological characteristics of source rocks in Qiannan depression, the depression is found to have a good hydrocarbon yielding condition. It is rich in source rocks, the organic matter of which is mainly sapropelic type. It has a good potential of hydrocarbon yielding. According to the degree of maturation of organic matter it can be divided into three regions: low maturation region, medium maturation region and over maturation region. The thermal evolution history of source rocks is
discussed，and hydrocarbon evolution and structure evolution are analyzed.And finally，some suggestions are made on the direction of exploration.

Key words: The South of Quizhou, Source rocks, Organic matter evolution, Evolution of exploration