A method (800, 1000) for conducting a marine seismic survey using a simultaneous source technique having a number (Nss) of simultaneous source firing sequences, wherein the simultaneous source technique is a random time dithering method, or a designed time dithering method, the method for conducting a marine survey comprising: towing (805, 1005), by a source vessel, a seismic source array comprising at least one seismic source; designing a baseline survey having a source vessel designed speed and a designed sampling interval selected so that the delay between shots is large enough such that for any given shot record a residual seismic energy from a preceding shot can be assumed to be negligible; activating (810, 1010) a first seismic source of the at least one seismic source according to a first firing sequence (311-315, 411-415, 511-515) in the simultaneous source technique; activating (820, 1020) one or more seismic sources according to the remaining Nss-1 firing sequences (321-324, 421-424, 521-525) in the simultaneous source technique, wherein adjacent firing sequences are activated without a delay of sufficient duration to permit the residual seismic energy from a preceding shot to be assumed to be negligible (1030, 1035); driving the source vessel at Nss times the designed speed while recording (840,1040) earth responses with overlapping signals; the method further comprising the following computer-implemented steps: performing separation of the overlapping signals in the recorded earth responses using a separation method based on the simultaneous source firing sequence; regularizing the separated earth responses; combining the regularized earth responses from the Nss simultaneous source firing sequences to form a seismic dataset with a sampling interval that is the designed sampling interval; and providing the combined earth responses for processing (850, 1050) properties of a subterranean section of the earth. towing (805, 1005), by a source vessel, a seismic source array comprising at least one seismic source; designing a baseline survey having a source vessel designed speed and a designed sampling interval selected so that the delay between shots is large enough such that for any given shot record a residual seismic energy from a preceding shot can be assumed to be negligible; activating (810, 1010) a first seismic source of the at least one seismic source according to a first firing sequence (311-315, 411-415, 511-515) in the simultaneous source technique; activating (820, 1020) one or more seismic sources according to the remaining Nss-1 firing sequences (321-324, 421-424, 521-525) in the simultaneous source technique, wherein adjacent firing sequences are activated without a delay of sufficient duration to permit the residual seismic energy from a preceding shot to be assumed to be negligible (1030, 1035); driving the source vessel at Nss times the designed speed while recording (840,1040) earth responses with overlapping signals; the method further comprising the following computer-implemented steps: performing separation of the overlapping signals in the recorded earth responses using a separation method based on the simultaneous source firing sequence; regularizing the separated earth responses; combining the regularized earth responses from the Nss simultaneous source firing sequences to form a seismic dataset with a sampling interval that is the designed sampling interval; and providing the combined earth responses for processing (850, 1050) properties of a subterranean section of the earth. performing separation of the overlapping signals in the recorded earth responses using a separation method based on the simultaneous source firing sequence; regularizing the separated earth responses; combining the regularized earth responses from the Nss simultaneous source firing sequences to form a seismic dataset with a sampling interval that is the designed sampling interval; and providing the combined earth responses for processing (850, 1050) properties of a subterranean section of the earth.