In order to understand the characteristics and flow characteristics of the low permeability carbonate reservoir of Middle East, in this paper, we take a Middle Eastern oil field as an example, using constant-rate mercury penetration technique, analyzing the micro pore structure characteristics of carbonate cores. The results show that, the pore radius distribution characteristics of different permeability is similar, mostly between 90-200μm, the peak occur at about 120μm. After that, we get the main factor affecting the reservoir physical quality of carbonate reservoir is throat rather than pore. And compared with the same permeability of sandstone cores, found that even if a poor sorting and strong heterogeneity of carbonate cores, but due to its throat contribution to permeability is very balanced, show the low permeability carbonate difficulty of development smaller than sandstone, only reducing the pore throat ratio, improve the ability of reservoir seepage, can have a good development effect.
