A proposed synthetic hydrodynamic model of surface-derived fluid circulations along detachment with or without syn-kinematic intrusion. Here we consider an active detachment-fault system creating a moderate permeability contrast (e.g., max ratio of 50) between the crust and the faults. Free topography model proves ineffective in prompting the deep percolation of surface-derived fluids into detachment segment (a). Modest topographic gradients are also insufficient to generate significant fluxes of surface-derived fluids (b). A heat source as a magmatic intrusion in the detachment foot wall enhances such downward fluid fluxes associated with hot upward flows in the hanging wall (c).