Methods of Reservoir Modeling on Braided River Sandstones

Key words: 
• braided /
• river /
• sandstones /
• heterogeneity /
• Kriging

Abstract: Braided river sandstones are widely distributed in Chinese continental ba sins;however,development for these reservoirs is not very satisfactory.The most important reason is the heavy heterogeneity of braided sandstones.This paper tak es the outcrop in the Zhangjiakou region,Hebei province as an example,which was densely sampled.Geological models are established based on the heterogeneity ana lysis of the sandstone,and then methods of modeling are probed.Kriging models a nd conditional simulation models are built based on porosity and permeability va riogram.Hurst indexes are calculated based on spectral analysis and rescale rang e analysis,which vary at the level of 0.8.One fractional permeability model is b uilt based on fractional geometry interpolation principles.The results suggest t hat Kriging models could reflect the macroscopic change of reservoir physical pr operties,conditional simulation models could reveal the reservoir heterogeneity, and the fractional model could reveal both the macroscopic physical properties a nd microscopic heterogeneity.Comparison of these models show that the fractional model is relatively the most effective model,which could be used in reservoir i n early development of oil fields.