川中磨溪地区致密碳酸盐岩储层可压裂性预测

FRACABILITY PREDICTION FOR TIGHT CARBONATE RESERVOIRS IN CHUANZHONG MOXI AREA

致密油气储层具有非均质性强、物性差、单井产量低、开发难度大等特点。为了准确识别高脆性层段、建立地层可压裂性模型,分析了可压裂性与岩石脆性、断裂韧性、抗压强度的关系,提出三者结合的可压裂性指数。研究表明,致密碳酸盐储层组成矿物简单,基于岩石力学参数法的脆性指数可以满足要求,较高的岩石脆性、较低的断裂韧性和抗压强度的地层为有利压裂层段。实例应用表明,新的预测方法能够准确刻画储层可压裂性,优选可压裂层段。

Tight oil and gas reservoirs are characterized by strong heterogeneity,poor physical properties,low single-well production,great development difficulty and so on.In order to identify the high-brittleness layer-interval and establish the fracability model accurately,the relationships between the fracability and the rock brittleness,fracture toughness and compressive strength were analyzed,and moreover the fracability index obtained by the above three properties was proposed.The study results show that the tight carbonate reservoir has the simple mineral compositions,and the brittleness index from the rock mechanical parameter method can meet the requirements.The formations with rather higher brittleness,lower fracture toughness and compressive strength are regarded as the much better fracturing layers.The case application shows that the new method can accurately characterize the fracability of the reservoirs and optimize the fractured intervals.