METHOD AND APPARATUS FOR AUTOMATICALLY PRODUCING REPRESENTATIONS OF THREE-DIMENSIONAL HORIZONS FROM PROCESSED SEISMIC DATA

An electronic system automatically produces representations of three-dimensional recommended horizons from processed seismic data. Significant events, in the form of turnings, are identified in all of the digitized traces that make up the processed seismic data. Pairs of significant events in adjacent traces are determined. The system determines these pairs through a mutual nearest neighbor technique, together with a technique for detecting similar signs. The system measures the curvature of the path formed by the paired turnings in successive digital traces and terminates the path at any point where the curvature exceeds a predetermined limit. The system then looks for three-dimensional continuity by looking for a closed loop of at least four turnings making up four pairs of turnings. These techniques yield at least one horizon represented in a first format. The recommended horizon, represented in a second format, is essentially extracted by the system through a recursive "walking" procedure for identifying all of the turnings in the recommended horizon and designating those turnings in the second format. At the same time, vertical uniqueness of each of the turnings in the recommended horizon is examined and if a subsequent turning is found to be on the same digital trace as a prior detected turning, the subsequent turning is not permitted. The second format is used for storage of the horizon and subsequent display.