Ghost-suppression optimized seismic source and method

A marine seismic source, comprising:

• cable segments housing source elements and configured to be towed one after another to form a towed line or rope and configured to emit waves having different frequencies while the source elements are towed at different predetermined depths, respectively,
• the predetermined depths being calculated such that down-going waves generated by a source element among the source elements at one of the predetermined depths interfere constructively with water-surface reflections due to up-going waves generated by the source element;
• and
• a controller configured to control the source elements to emit the waves with predetermined time delays, respectively, so that the waves from all the source elements interfere constructively with each other to yield a spike-like signature of the marine seismic source at an explored structure.

A method for generating waves usable for exploring a formation under the seafloor, the method comprising:

• towing source elements in water, at different predetermined depths;
• and
• controlling the source elements to emit waves having different frequencies, respectively, according to a sequence determined based on the predetermined depths, such that the waves combine to yield a spike-like signature of the source,
• wherein the predetermined depths are calculated such that water-surface reflections of the waves generated by a source element among the source elements interfere constructively with the waves propagating toward the explored formation and generated by the source element, and
• wherein the controller further controls the source elements to emit the waves with predetermined time delays, respectively, so that the waves combining from all the source elements interfere constructively with each other to yield the spike-like signature of the marine seismic source at the explored formation.