Fracture Modeling Method of Asmari Formation Carbonate Reservoir in G Oilfield, Middle East

Fractures are developed in the carbonate reservoir of Asmari Formation in G oilfield in the Middle East, which aggravates the heterogeneity of the reservoir and is an important factor affecting the productivity of producers and the rule of water cut rising. Due to the lack of core and imaging logging data and weak seismic response of reservoir fractures, it is difficult to carry out fracture evaluation, prediction and modeling in G oilfield, which is a key problem restricting the efficient development of the reservoir. Firstly, an inversion method of fracture density based on formation anisotropy is established by using cross dipole array acoustic logging (CDAAL) data, which provides a reliable evaluation result of single well fracture density for fracture density modeling. Secondly, based on deep mining of fracture information in seismic attributes and integrating artificial intelligence algorithms, a machine learning based seismic multi-attribute fusion fracture prediction method is established to predict the distribution of fractures in the study area. Finally, a fracture density model is established with the single well fracture density as the hard data, the fracture planar distribution prediction as the soft constraint, then a discrete fracture network (DFN) model is established based on the fracture density model with fracture parametric statistics law as the constraint by random simulation method. Research has shown that the history matching result based on the dual-porosity model is significantly improved compared to the single-porosity model, which confirms the reliability of the fracture modeling method and results. At the same time, the research results have been applied to the optimization of well types and locations during the development of G oilfield. 4 horizontal wells have been implemented in areas with relatively developed fractures. The average initial productivity of them is 3–5 times that of the vertical wells in the same period, which has improved the reservoir development effect.