Abstract:

For the problem of low awareness of deep oil， the main control factor of different kinds of reservoirs and deep crude oil accumulation model in Shuangcheng fault depression of Songliao basin, we make sure the main controlling factors such as the thickness of source rock, the hydrocarbon expulsion intensity, the formation of entrapment and its relationship with the main accumulation period, the sand-source configuration, the overpressure and filling resistance, on the base of rock-eval, chloroform asphalt “A” and homogenization temperature of inclusion. The result is that: 1) There are four kinds of reservoirs, such as fault-anticline, anticline and fault-lithologic reservoir in the 3rd Member of Denglouku Formation in the west structure and the east fault bench, tight reservoir in the 4th Member of Yingcheng Formation within the central sub-sag. 2) The structure reservoir in the 3rd Member of Denglouku Formation is controlled by the union of mudstone, oil-source fault and effective trap. The abundant source rock is the material base for oil reservoir, and the structure trap in the 3rd Member of Denglouku Formation is almost complete before the hydrocarbon expulsion, fault is the main target for oil migration, the configuration relationship of sandstone and source determine the effective of structure trap. 3) The tight oil in the 4th Member of Yingcheng Formation is under the control of lithologic trap, source and overpressure. The tight oil is controlled by the hydrocarbon expulsion intensity, while overpressure is the main power for tight oil charging. We set up three kinds of accumulation models in different regions based on forming condition and main controlling factors of tight oil, such as “reservoir and source separate, migration along the fault in long distance and enrichment in the high point” in west structure, “reservoir and source nearby, long distance transmission of faults and connected sandstone in short distance, accumulate in effective trap” in east fault bench, and “reservoir superpose on source, overpressure drive and migrate along the fissure, enrichment in sweet points” in the central sub-sag.

Key words: deep oil')">

deep oil, tight oil, forming condition, controlling factor, Shuangcheng fault depression, Songliao basin