Seismic marine vibrator

A seismic marine vibrator comprising:

• a plurality of first plates arranged along a longitudinal axis;
• a plurality of second plates arranged along the longitudinal axis, the first plates alternating with the second plates;
• longitudinal and peripheral first and second elements angularly distributed about the longitudinal axis and respectively secured to the first and second plates;
• an actuator operable to reciprocate the first elements relative to the second elements along the longitudinal axis so as to reciprocate the first plates relative to the second plates;
• peripherally closed air-filled chambers defined between respective first pairs of adjacent plates;
• peripherally open chambers defined between respective second pairs of adjacent plates alternating with said first pairs of adjacent plates, the volume of said peripherally open chambers being varied when the first plates are reciprocated relative to the second plates so as to take in and expel water radially to generate an acoustic wave.