Besides the difficulty in cognition,distributing prediction and quantificational token for fracture, the more seriousdifficulty is study for fracture seepage mechanism and model.

• 除了对裂缝的认识、裂缝分布预测以及裂缝参数的定量表征等研究存在困难外，更重要的是对裂缝渗流机理的认识及渗流模型的研究还不完善。