Abstract: The advanced results of subsurface fluid dynamics in the crust observed by vanous workers are introduced. Based on integrated and systematic analysis of these results, a conceptual model and its corresponding mathematical model are developed. In this model, the crustal seepage field was divided into three zones according to its permeability and dominant factors on which the fluid dynamic characteristics affect, that is shallow zone(0 ~ 6 km), transitional zone(6 ~ 17 km) and deeper zone(> 17 km). The various driving forces on subsurface fluids were normalized as''geological force" and represented as sources or sinks in flow equation. The rates and magnitudes of diverse geologic processes are analyzed in different geologic environments. The widely occurred phenomenon in the crust, anomalous pore pressure, is explained from the viewpoint of subsurface fluid dynamics, and it is suggested that the periodic earthquakes is the dominant factor in forming the anomalous pore pressure process.

Key words: Subsurface fluid dynamics model, Anomalous pore pressure, Geologic force