关键词: 薄差油层, 层间窜流, 平衡压裂技术, 数值模拟, 隔层, 下限厚度

Abstract: In the fracturing process for making the horizontal fractures, the interlayer channeling often takes place. In order to investigate the causes of interlayer channeling, the finite element numerical simulations were carried out by means of the software ANSYS. The results demonstrate that the interlayer channeling is resulted from the shear destruction of the second cemented interfaces nearby. The shear destruction is induced by the imbalance of pressures acted on the upper and lower surfaces of interlayer. The lowest limits of interlayer thickness for the balance fracturing technology and the ordinary fracturing technology were determined on a series of calculations. When the thickness of interlayers is over the limits for these two technology, the interlayer channeling would probably take place in the practice. This result may provide a quantitative reference for putting the balance fracturing technique into practice.

Key words: thin and bad oil layer, interlayer channeling, balance fracturing technique, numerical simulation, interleyer, low thickness