a method for simultaneously operating multiple seismic vibrators using continuous sweeps for each vibrator , and recovering the separated seismic responses for each vibrator with the earth signature removed . each vibrator is given a unique , continuous pilot signal . the earth response to the motion of each vibrator is measured or estimated . the vibrator motion records for each vibrator and the combined seismic data record for all the vibrators are parsed into separate shorter records . the shorter records are then used to form a system of simultaneous linear equations in the fourier transform domain , following the hfvs method of sallas and allen . the equations are then solved for the separated earth responses .