1. A method for determining a parameter of interest of a subsurface region of earth formations comprising: (a) obtaining seismic survey information about the subsurface region; (b) identifying a plurality of interpreted seismic horizons of interest from the obtained survey information; (c) obtaining estimated seismic velocities corresponding to at least one interval between at least one pair of said plurality of seismic horizons; (d) calibrating the estimated seismic velocities to the parameter of interest (e) using the results of said calibration and the obtained seismic velocities to obtain the parameter of interest at any location within the seismic survey.