Reseach on the diposite environments about source rocks in south Ordos Basin

Aim To probe the relationship between the environment and source rocks geochemistry characteristics in south Orduos Basin.Methods Combined mainly geochemical data of the source rocks with diffrent bore specimens, the sedimentary environments about the source rocks are studied in abundance and types of the organic metters as well as saturated hydrocarbon chromatogram parameters in the source rocks. And the influence factors are analysised finaly in south Ordos Basin.The major elements and palaeclimate as well as palaeosalinity are researched. Results The studies demonstrated that the palaeclimate was moister relatively and palaeosalinity was lighter. It is considered that the zones deposited in half deep lake to deep lake where the organic matters could have been buried and preserved contemporarily in strong reducing environment, there are more abundance of organic metters in the source rocks such as black grey mudsource. In the zones deposited in the river to delta there are less abundance and the worse types in the source rocks like green grey mudstone. Conclusion Among the source rocks, there is less abundance in the carbonate source rocks that deposited under the more oxide condition, in which terrienous clastic deposits were inadequate during longer time and the palaeclimate was drier relatively. The more reducing and favorable sedimentary zones are better place,there are higher abundance of organic metters in the source rocks with strong reducing environment,where the organic matters can be buried and preserved contemporaryly, and the source rocks are generally high in organic content, and vice versa.