The researchers developed a new model to predict the permeability of coalbed methane reservoirs with a high-dip angle in NW China. They used laws of fluid flow and fractal theory to calculate the fracture porosity and formation cementing index. By introducing a curvature factor, they accurately estimated the permeability of the original fractures in the reservoirs. The model was validated against well testing data and showed a strong correlation. This model can help accurately predict the permeability of low rank coals in the southern Junggar Basin, indicating a complex reservoir structure.