Abstract: The invention provides an improved method and apparatus (10) for measuring the velocity and amplitude of sound waves (150) from acoustic pulses (145) generated near the mudline (130) of the seafloor (120). The apparatus (10) includes a seismic source (30) for generating the acoustic pulses, one or a plurality of vertically spaced sensors (50) located vertically below the seismic source (30) for sensing when the sound waves (150) impact the sensors (50), a hydrophone sensor (200) located on the vessel (60) for measuring the distance to the seismic source (30) a crane and winch for pulling the embedded sensors (50) upwardly and out from the sediments, and means (100) for firing the seismic source when said sensors (50) are being pulled upwardly, for taking amplitude and velocity measurements from each sensor, and for determining the distance the sensors have been pulled upwardly for each acoustical pulse operation.

Abstract: The invention provides a system having at least one subocean bottom seismic device, such as a seismic source (10) or a seismic detector (600), and a planting unit (300). When the planting unit (300) is lowered it selectively implants the seismic device at predetermined locations in the ocean bottom, it releases from the implanted seismic device, and, when raised, uncoils a signal cable (30) from the implanted seismic device. The signal cable (30) which is capable of retrieving the implanted seismic device (10, 600) is connected to an anchored buoy (40) which contains a first communications unit (70). A second seismic device (100) is carried in a predetermined pattern near the implanted seismic device and is connected to a second communication unit (130).

Abstract: The invention provides an apparatus (10) and method for measuring the velocity and amplitude of a pressure wave (310) from an acoustic pulse (300) through layers of sediment (140) located below the mudline (130) of the seafloor (120). The apparatus (10) includes an implosive seismic source (30) for injecting acoustic pulses (300) into a region of the sediments (140), a plurality of vertically spaced sensors (50) located vertically below the seismic source (30) for sensing when the pressure waves (130) from the acoustic pulses (300) impact the sensor (50) or the amplitude of the pressure wave (310), and a digital recording system (100) for recording the signals from the sensors (50).

Abstract: A high resolution seismic data acquisition system is made up of an electronically-fired shotgun source integrally connected to a detector-recording means displaced from the shotgun source.