APPARATUS AND METHOD FOR ACCURATELY DETERMINING THE LOCATION OF EVENTS SUCH AS PEAKS IN SEISMIC DATA

An operator sitting at a workstation (110) views, on a display, a multitude of seismic traces having one or more horizons indicated therein by a plurality of sets of events (such as peaks or troughs or zero crossings) (78) on the seismic traces. The operator uses a mouse (120) to draw a line from left to right across a plurality of seismic traces being displayed on the workstation display screen (110b). At this point, the line does not lie on the events (such as the peaks) (188) of the seismic traces. Therefore, the line does not yet represent a horizon (62) in an earth formation. The operator presses a key on the keyboard of the workstation. In response to the pressing of this key, the workstation processor executes a "snapper software" (116) in accordance with the present invention. When the snapper software (116) of the present invention is executed, the line, previously drawn by the operator across the seismic traces on the workstation display screen, moves from one location, not corresponding to the events (such as the peaks) of the seismic traces, to another location, corresponding to the events (such as the peaks) of the seismic traces. When the line moves to said another location on the screen display, the line now lies directly on a set of events (such as peaks) of the seismic traces which underlie the line. Now, the line does accurately represent a horizon in a earth formation. The snapper software of this invention can determine the peaks, the troughs, and the zero crossings of the seismic traces. As a result, the horizon depicted by the snapped line on the workstation screen display is accurately represented. Un opérateur assis à un poste de travail (110), voit, sur un afficheur, une multitude de traces sismiques possédant un ou plusieurs horizons signalés par plusieurs ensembles d'événements (tels que les crêtes, des dépressions ou des passages à zéro)(78) sur les traces sismiques. L'opérateur utilise une souris (120) pour dessiner une ligne de gauche à droite, sur plusieurs traces sismiques en cours d'affichage (110b) sur l'écran d'affichage (110b) du poste de travail. A ce niveau, la ligne ne se trouve pas sur les événements (tels que des crêtes)(188) des traces sismiques. Par conséquent, la ligne ne représente par encore un horizon (62) dans une formation terrestre. L'opérateur enfonce une touche du clavier du poste de travail. En réponse à cette opération, le processeur du poste de travail exploite (110) un logiciel de capture (116) selon