Comparison of the HydrocarbonGenerating Conditions of the Lower Cretaceous from the Jiuxi and Jiudong Depression

Key words: 
• hydrocarbongenerating conditions /
• the Lower Cretaceous /
• source rock /
• Jiuxi Depression

Abstract: Based on the research of the organic geochemistry characteristics of source rocks, the hydrocarbongenerating conditions of the Lower Cretaceous source rocks in Jiuquan Basin are evaluated systematically by means of being classified by sag and formation.Moreover, the hydrocarbongenerating conditions of the Lower Cretaceous source rocks from the Jiuxi Depression and those of Jiudong Depression are compared. The research results show that the hydrocarbongenerating conditions of the Lower Cretaceous source rocks from the Jiuxi Depression have a tendency of growing better from the Zhonggou Formation to the Xiagou Formation and to the Chijinbu Formation, however, in the Jiudong Depression, there have an opposite tendency showing that the hydrocarbongenerating conditions grow worse gradually from up to down, which reflects the characteristics that the better source rock is immature but the mature source rock is not good. The Xiagou Formation and the Chijinbu formation from the Jiuxi Depression are the main contributors to the hydrocarbongeneration of the Lower Cretaceous source rocks from the Jiuquan Basin. The research results will be of great significance on the exploration of oil and gas in Jiuquan Basin.