In order to enhance gas recovery

it is necessary to construct pore network model and quantitatively describe micro-pore-scale percolation mechanism based on micro-pore structure.Taking cores of the Upper Sha-ximiao Formation in the Xinchang gas field of western Sichuan Basin as an example

this paper studies 3D reconstruction of pore structure.First

using micro-CT to scan core to get projection data

and using the FDK algorithm for construction of grayscale images.Then based on experimental porosity

using 2-value segmentation to cut grayscale images and using ray tracing algorithm to get 3D pore structure image(digital core).Statistical analysis of the properties of digital core shows that the porosity of digital core is almost identical to the measured core porosity with a relative error of only 0.1

which is in coincide with the properties of Upper Shaximiao Formation in the Xinchang gas field.It shows that reconstruction of micro pore structure with micro-CT scanning is feasible.The study provides a solid foundation for pore network modeling and subsequent microscopic flow simulation study.