Automated process for determining subsurface velocities from seismograms

Claim 1

In seismic exploration wherein the seismic velocity characteristic of the earth is determined from a suite of seismograms representing the reflection of seismic energy from reflecting points in the earth, said suite of seismograms being obtained from detectors spaced along a line of exploration, the method of automatically processing said seismograms in a data processing machine comprising: a. for given values of dip, travel time T0, and seismic velocity V generating in said data processing machine physical representations of the corresponding travel times tx for each of the traces in said suite of seismograms; b. for each value of tx generated in step (a), selecting a window of each trace, said window having a time length which approximates the expected length of a seismic wavelet in said seismograms; c. detecting the presence of a seismic signal in the windows across said traces, said windows having time shifts from trace to trace corresponding with an assumed value of velocity and an assumed value of dip; d. repeating steps (a) - (c) in said data processing machine for different iterated values of dip, for different iterated values of velocity V, and for different iterated value of travel time T0, e. generating a function indicative of the presence of the detected seismic signal for each travel time T0; and f. for each value of dip generating functions representing the maximum signal detected at each travel time T0 so that peaks in said functions indicate the probable presence of reflections from dipping subsurface reflectors at the assumed dip and the maximum peak at each travel time T0 in said functions indicates dip.