Abstract: A seismic signal is created, processed and recorded and then analyzed to determine the nature of subterranean formations.

Abstract: In a seismic exploration system, the waveforms provided from a plurality of seismic sources are phase shifted so as to maximize the strength of signals received by a plurality of seismic receivers and the signals output from the plurality of seismic receivers are phase shifted so as to substantially maximize the strength of the composite signal which results from the summation of the output from the plurality of seismic receivers.

Abstract: In the injection of fluids into subsurface geological formations, such as for the purpose of recovering a mineral in that formation, it is important that the flow progress of that fluid is known at all points in the subsurface. This information is provided by injecting a selected fluid into the formation. This fluid may be a gas, or a liquid, or a mixture of gas and liquid. When this fluid is in the subsurface formation there will be a mixture of gas and liquid in selected proportion in the formation. This mixture in a geologic formation overlain by a shale, for example, will have a much higher reflection coefficient. A source of seismic waves is operated at the surface, and the received reflections are compared between spaced positions on the surface.

Abstract: A geophone is disclosed which includes at least two transducers having axes which are perpendicular to each other for sensing vertical and horizontal in-line components of seismic waves. In one arrangement, the geophone includes a signal processor which includes active circuit elements responsive to the transducer output for suppressing ground roll components included in the transducer outputs. At least one of transducer output signals with ground roll signal components suppressed therefrom is connected to a remote location for recording. When more than one signal is to be sent from the geophone to the remote recording location, a mulliplexer is provided at the geophone for transmission of a plurality of geophone output signals to the remote location over a single transmission path, such as a dual-conductor transmission line. Analog and digital versions of the geophone are disclosed.

Abstract: Apparatus for shear wave logging of a fluid-filled borehole which consist of an elongated housing defining an air cavity and containing first and second spaced geophone housing each having an orthogonal pair of horizontal motion detectors secured therein for detection of horizontal shear waves along said borehole as generated from a seismic source in a frequency range having wavelengths that are long relative to the length of housing.

Abstract: A signal having the form cos (.OMEGA.t+.phi.) where .OMEGA. is the frequency of the signal and .phi. is a phase angle which may be zero is phase shifted to improve the results of the summation of such a signal with other signals having the same form but different phase angles.

Abstract: High resolution, high penetration marine seismic stratigraphic system wherein a slanted cable comprising spaced-apart hydrophone arrays gather seismic reflections so that the corresponding primary and ghost reflections from a common interface gradually are spaced apart. The primary reflections are time aligned and stacked. The ghost reflections are phase reversed, time shifted and time aligned to coincide with the time aligned primary stack and then stacked to give a combined primary and ghost stack, which effectively includes almost twice the information as from the primary stack alone. No inverse notch filters are needed to correct for the ghost phenomenon. Focused noise out of the vertical plane is also virtually eliminated.

Abstract: Faults in an underground coal seam are located by firing a shot at one point in the seam and detecting the seismic reflections in an array of geophones. Signals from the geophones are recompressed and analyzed according to an exponential formula to give a holograph of the seam and to predict the fault pattern.

Abstract: This specification discloses a system and method for processing deconvolved seismic traces to compensate for phase distortion introduced in deconvolving the traces. The method provides for automatically processing the traces in an automatic data processing machine. A filter is generated from the signal pulse of the seismic energy applied to the earth in obtaining the seismic traces and this filter is applied to the deconvolved seismic traces to phase correct the traces.

Abstract: This invention relates to continuous wave seismic exploration and more particularly to generating long sweep continuous seismic waves and utilizing signals resulting from detection of said seismic waves to significantly enhance the signal-to-noise ratio while simplifying the required processing.