초록 ▼

A marine seismic reflection prospecting system reduces coherent noise by applying a scale factor to the output of a pressure transducer and a particle velocity transducer positioned substantially adjacent one another in the water. The transducers can be positioned at a point in the water above the b

A marine seismic reflection prospecting system reduces coherent noise by applying a scale factor to the output of a pressure transducer and a particle velocity transducer positioned substantially adjacent one another in the water. The transducers can be positioned at a point in the water above the bottom and, thereby, eliminate downgoing components of reverberation, or they can be positioned on the water\s bottom and, thereby, eliminate both upgoing and downgoing components of the reverberation. The scale factor, which derives from the acoustical impedance of the water or water-bottom material, can be determined both deterministically and statistically. The former involves measuring and comparing the responses of the pressure and velocity transducers to a pressure wave induced in the water. The latter involves comparing the magnitude of the pressure signal autocorrelation to the pressure and velocity signal crosscorrelation at selected lag values or, alternatively, comparing the magnitude of the pressure signal autocorrelation to the velocity signal autocorrelation at selected lag values.

대표청구항 ▼

An improved seismic reflection method for geophysical prospecting in water covered areas, comprising the steps of A. generating a seismic wave for reflection from earth strata, B. detecting water pressure at a first position in the water resulting from said seismic wave and generating a signal repre

An improved seismic reflection method for geophysical prospecting in water covered areas, comprising the steps of A. generating a seismic wave for reflection from earth strata, B. detecting water pressure at a first position in the water resulting from said seismic wave and generating a signal representative thereof, C. detecting water velocity at a position substantially near said first position resulting from said seismic wave and generating a signal representative thereof, and D. generating an enhanced seismic reflection signal by multiplying at least one of said water pressure-representative signal and the water velocity-representative signal by a scale factor dependent upon an acoustical impedance of a substance through which said seismic wave travels, and by summing said scaled water velocity-representative and water pressure-representative signals, and enhanced seismic reflection signal being substantially free of at least downwardly-propagating components of reverberation of said seismic wave within the water.