各向异性储层地层测试椭球形流动压降解释模型

Pressure drop interpretation model of ellipsoidal flow for formation testing in anisotropic reservoir

关富佳 曹宝军 太东华

长江大学湖北省油气钻采工程重点实验室;长江大学石油工程学院;大庆油田有限责任公司勘探开发研究院;胜利石油管理局钻井工程技术公司;

1.Key Laboratory for Drilling and Production Engineering of Hubei Province, Yangtze University, Jingzhou 434023, China;
2.School of Petroleum Engineering, Yangtze University, Jingzhou 434023, China; 3.Exploration and Development Research Institute, Daqing Oilfield Co. Ltd., PetroChina, Daqing 163712, China; 4.Drilling Engineering and Technology Company, Shengli Petroleum Administration Bureau, SINOPEC, Dongying 257000, China

根据电缆地层测试的压降数据得到大体可靠的储层渗透率参数,为仪器进一步精确测试提供可靠的测试参数,提高测试参数解释精度。基于水平渗透率大于垂向渗透率的基本假设,分析了各向异性储层中地层测试的渗流形态,在此基础上,应用渗流力学理论和坐标变换方法,建立了用于各向异性地层的单探头电缆地层测试椭球形流动压降解释模型。该模型考虑了实际地层具有各向异性特征,比基于地层各向同性假设而建立的解释模型更符合储层实际。应用数值模拟技术模拟电缆地层测试压降数据,并应用新模型进行测试参数解释,与数值模拟输入参数进行解释精度对比。结果表明,新模型比原模型具有更高的参数解释精度,能够更好地为现场精确测试提供快速、准确的参数估计。

To obtain quickly the reservoir permeability parameters by pressure drop data from wireline formation testing, supply a parameter range for further precision testing and guide selecting correct testing parameters, the interpretation accuracy of reservoir parameters must be improved. This paper assumed that reservoir permeability in horizontal direction was greater than that in vertical direction and analyzed the flow shape of wireline formation testing in anisotropic reservoir. Based on this, the pressure drop interpretation model of ellipsoidal flow for formation testing in anisotropic reservoir was build up by seepage mechanics theory and coordinate transformation. This model considered the anisotropic characteristics of actual formation and was corresponded with the actual formation compared with the interpretation model established based on anisotropic reservoir assumption. The pressure drop data from numerical simulation was interpreted by the new model and the result was compared with numerical simulation input parameter. The result shows that the new model has a higher interpretation precision than that of the original model and it can supply quick and accuracy parameter for further testing.