Semi-automatic picking in real seismic data

Numerical analysis of seismic data requires information to be expressed in terms of frequency, amplitude, phase and velocity. Picking in seismic data usually gives timing information for velocity analysis of reflected and refracted waves, for amplitude vs. offset studies (AVO), and for geological interpretation. In a complex geological setting, in the presence of ground roll or other organized interference and in seismic data with low ratio between signal and noise caused by energy attenuation, recognizing and following the horizons can be particularly critical. Errors in the travel time table, often unavoidable, propagate like random errors in every subsequent study. For these reasons, it is necessary to introduce a method to minimize wrong interpretations when determining the picked travel times. The method that we propose does not need any seismic data processing and can be applied in many geophysical fields. The algorithm is founded on the hypothesis that the wavelet in the same reflector changes laterally and with offset, but the crosscorrelation factor is sufficiently close to one. In this way, it is possible to extract coherent events from noisy seismic data.