Abstract: A method for locating leak from a tank containing a fluid using acoustic signals by adaptively correlating the phase of the acoustic signals to determine a first set of possible leak locations and subsequently correlating acoustic signals from a second set of locations on the tank to determine a second set of possible leak locations and converging the first and second set of possible leak locations to determine the location of the leak.

Abstract: A method for conducting a three-dimensional subsurface seismic survey utilizing a plurality of seismic receivers arranged in an orthogonally uniform pattern is disclosed. A predetermined pattern of shotpoints is arranged such that every point in the surface area of interest is sampled over a desired range of offsets and a full range of azimuths. The utilization of shotpoints outside the pattern of receivers allows examination of a subsurface area which is greater than the area of the pattern itself. The output of each receiver in the pattern is simultaneously recorded for seismic energy applied to the surface of the earth. Where the area of interest is quite large, a multitude of patterns of seismic receivers may be utilized to ensure coverage of the entire area. In a marine application of the present invention a plurality of seismic receivers are arranged in an orthogonally uniform pattern under a body of water or by utilizing multiple parallel marine streamers towed by one or more tow boats.

Abstract: A method for conducting a three-dimensional subsurface seismic survey utilizing a plurality of seismic receivers arranged in an orthogonally uniform pattern is disclosed. A predetermined pattern of shotpoints is arranged such that every point in the surface area of interest is sampled over a desired range of offsets and a full range of azimuths. The utilization of shotpoints outside the pattern of receivers allows examination of a subsurface area which is greater than the area of the pattern itself. The output of each receiver in the pattern is simultaneously recorded for seismic energy applied to the surface of the earth. Where the area of interest is quite large, a multitude of patterns of seismic receivers may be utilized to ensure coverage of the entire area.

Abstract: A seismic exploration method and apparatus in which non-uniformly distributed noise signals generated by wind, machinery, or surface wave propagation and received by the sensing geophones are cancelled by the utilization of adaptive filter processing. A number of horizontally sensitive geophones are disposed along the surface of the earth to detect surface waves induced in the surface of the earth at a plurality of spaced locations throughout an entire area of investigation. Similarly, a number of wind noise and mechanical noise detectors are utilized to detect airwave and noise signals at a plurality of locations throughout the area of investigation.

Abstract: A receiver array for detecting seismic reflections is composed of geophones of several different natural frequencies divided into subarrays having lengths compatible with the natural frequencies of their geophones and the seismic wavelengths at the recording site. This system provides both frequency and spatial filtering at the sensors so as to enhance the signal-to-noise ratio of broad-band seismic signals.