摘要
低渗、特低渗油气藏水平井的分段压裂产能模拟计算,一般不考虑储层应力变化对裂缝形态的影响,计算误差较大。将二维诱导应力场计算模型与预估的每段分压时间间隔相结合,计算已存在的人工裂缝对应力场变化的影响,预测后续压裂人工裂缝形态,并根据预测结果建立地质模型,采用三维三相黑油模型计算水平井压后产能,从而建立了考虑人工裂缝存在时应力场变化后的水平井分段压裂产能计算方法。结果表明,在考虑应力场变化时,人工裂缝形态会发生明显变化,由预期的横切裂缝,变成类似于"T"形的人工裂缝,且横切缝部分会远离预定的射孔位置。JM油藏实例分析得出,考虑8条横切裂缝存在时水平井产能与不考虑应力场变化时所计算的产能相比,5年末的累计产量相差5.6%,验证了进行水平井分段压裂产能计算时考虑实施过程中应力场变化的必要性。
The effect of reservoir stress variation on the fracture morphology is usually not considered in the simulation calculation on staged fracturing productivity of horizontal wells in low permeability and ultra-low permeability oil and gas reservoirs, leading to large calculation errors. In this paper, the 2D induced stress feld computation model was combined with the estimated staged fracturing time interval in each stage to calculate the effect of the existing artifcial fractures on the stress feld variation and predict the artifcial fracture morphology in subsequent fracturing. Then, based on the prediction results, a geologic model was established, and the 3D three-phase black-oil model was used to calculate the post-fracturing productivity of horizontal wells. Finally, a staged fracturing productivity computation method of horizontal wells with consideration to the stress feld variation in case of existence of artifcial fractures was defned. According to the study results, when the stress feld variation is considered, the artifcial fracture morphology would change obviously, from the expected transverse fractures to T-like artifcial fractures, and some transverse fractures would be far away from the planned perforation location. The feld application in the JM reservoir shows that the fve-year cumulative production of horizontal wells obtained with consideration to the existence of 8 transverse fractures is 5.6% different from that without consideration to the stress feld variation. This verifes the necessity that the stress feld variation should be considered in calculating the staged fracturing productivity of horizontal wells.
出处
《石油钻采工艺》
CAS
CSCD
北大核心
2016年第3期347-351,共5页
Oil Drilling & Production Technology
基金
国家科技重大专项"低渗
特低渗油气储层高效改造关键技术"(编号:2011ZX05013-03)
中国石油天然气股份有限公司科技重大专项"特低
超低渗油藏高效改造关键技术研究"(编号:2011B-1202)
关键词
低渗透
特低渗透
水平井分段
应力场
产能模拟
low permeability
ultra-low permeability
horizontal well section
stress feld
productivity simulation
