Abstract:

The interlayers of inner buried hills are the main factors that control the hydrocarbon distribution. Starting from the exploration practice in Jizhong depression, this paper studies the characteristics of lithology, resistivity, seismic reflection and distribution of interlayers using the seismology, geology, logging and assay data. The result shows that the interlayers of inner buried hills in Jizhong depression have multiple types of rocks with preferable sealing ability. The distribution characteristics of interlayers in horizontal and vertical directions influence the hydrocarbon distribution of the inner buried hill reservoir. According to the relationship of interlayer and hydrocarbon, the patterns of hydrocarbon distribution can be classified into four main types,ie. top barriering,bottom barriering,lateral barriering and top-bottom sandwich. Explorations should be focused on the deep inner traps in the central uplift belt, and the inner traps of the slope belt and the fault step belt.

Key words: Jizhong depression, inner buried hill, interlayer characteristic, hydrocarbon distribution, hydrocarbon accumulation model