CONTROL OF RESERVOIRACCUMULATION BY SYNSEDIMENTARY FAULT IN SUNING OILFIELD, RAOYANG DEPRESSION, CHINA

摘要

The Suning Oilfield is located in the oil-producing trough in the eastern part of the Raoyang Sag. The main oil-bearing strata are the Esl and Ed3 Member. The sedimentary faults are very developed and belong to tectonic-lithologic reservoirs. However, the current understanding of reservoir formation is still unclear: First, the formation of high- oil reservoirs is not ideal, and there are many failed wells for exploration; second, the low-lying down plates often obtain high-yield wells; and third, the faults in densely-drilled areas are prone to high yields. Based on a comprehensive study of geophysical, logging, geological and oil-producing production data, the following accumulation laws of the oilfield are found: the sedimentary fault can provide both oil and gas migration channels and control sand body deposition. Large faults with direct faults on the surface often have multiple fault activations, and there are many oil and gas losses in nearby reservoirs. The formation of the near-construction transition zone is the descending disk of the reverse normal fault. Because of its small hydrocarbon migration resistance and short distance, it is easier to accumulate. The sand body with dense faults is constructed, and the oil and gas supply is sufficient and easy toform. Directional wells with fault planes are more likely to drill high-yield reservoirs while wells far from faults have low success rates.