Patent ID: 7050356

Claim:
A method of seismic surveying comprising the steps of: actuating the or each vibrator in a first vibrator group at time T 0 ; and actuating the or each vibrator in a second vibrator group at time T 1 , where T 0 <T 1 <T 0 +S 1 +L where S 1 is the sweep time of the first vibrator group and L is the listening time and wherein T 1 −T 0 <(n−1) S 1 f 0 /n(f 1 −f 0 ), where n is a natural number, f 0 is the lower frequency limit of the vibrator sweep and f 1 is the upper frequency limit of the vibrator sweep; wherein at least one of the first vibrator group and the second vibrator group comprises at least two vibrators.