The mutli-body theory drives cognition and application for the research of hydro-geological unit

System theory drives the progress of hydrogeology.Furtherly,we apply muti-body theory to describe and analyze the hydro- geological unit at micro- and macroscopic-scale by the generalized way.And the hydro-geological unit can be effectively depicted by it.As a result,this fully indicate that it is applicable significance for the analysis and cognition of the hydro geological unit.