Pore structure characterization of tight oil reservoirs with fractal theory

摘要

The microscopic pore structure characteristics of tight oil reservoir are of great importance of effective tight oil development. The fractal dimension can effectively describe the pore size distribution and characterize the heterogeneity of pore structure. There are several methods of calculating fractal dimension from mercury intrusion curve, such as Mandelbrot model, capillary tube model and three-dimensional sphere model, but the calculated results varies from different methods. Using mercury intrusion porosimetry and three different fractal models, the good relationships between fractal dimension and petrophysical properties of tight sandstone core samples have been found, which are beneficial to characterize the heterogeneity of pore structure of tight sandstone reservoirs.